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Unmanned Spaceflight.com _ Mars _ Nozomi in perspective

Posted by: pandaneko Oct 23 2011, 09:12 AM

http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf

Above pdf file will be translated for aspiring students in aeronautics, control engineering etc. so that in future lay people like me will be able to enjoy planetary scenes and events without worrying about failures.

The overall title is "Looking into the causes of failure and trying to find the right measures to take for the future with respect to the 18th scientific satellite (PLANET-B ) not inserted into Mars orbit as planned" and it is dated 21 May 2004.

This file is very much detailed at 1.1 megabytes and the number of pages is about 40, I think. In addition, I will be translating 3 more files after this particular file. They will be;

1. ISAS file with views and comments on the failure
2. Another ISAS file, a newsletter written out in a series of 4 individual letters.
3. JAXA file, which is a press release and it is a very concise document with just sufficient details.

Re concise link making I tried a few times, but I simply failed and all the links will be fully pasted out as required.

Pandaneko

Posted by: pandaneko Oct 24 2011, 08:53 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

(preliminary, just a gist of SAC comments dated 26 May 2004 on the above report as follows)

We accepted above report. Most grateful to those who spent time on this report out of their own busy schedules.

This report talks about two major failures and the findings will be refelected in the future science satellites design philosophy particularly in the areas of;

1. design changes
2. ground tests
3. policy on imported parts
4. failure separation
5. software operation

We hope that JAXA will be making best use of this report for their routine inspection/checking procedures and R&D activities.

P

(I will upload the list of contents immediately after this)


Posted by: pandaneko Oct 24 2011, 09:37 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

(list of contents is as follows)

Preliminary・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・1

Ⅰ.Outline of Nozomi

1.Outline of the satellite・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・2

(1) Objectives of Nozomi・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・2
(2) Outline of the satellite・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・2
(3) Instruments on Nozomi and the outline of the knowledge obtained by the time orbit insertion was abandoned・・・・2

2.History of development and its background・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・2

(1) History of Nozomi development・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・3
(2) Science targets of Nozomi・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・3
(3) Nozomi development philosophy・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・4
(4) Nozomi design philosophy・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・5
(5) Lighter Nozomi due to launch postponement・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・6

3.Outline of the history leading up to abandonment of orbit insertion・・・・・・・・・・・・・・・・・・・・6
(1) Occurrence of fuel system failure (20 October 1999)・・・・・・・・・・・・・・・・・・・・・・6
(2) Occurrence of coms. and thermal control system faillure (25 April 2002)・・・・・・・・・・・・・・・・・・・・7
(3) Operation for fault recovery・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・7
(4) Abandonment of orbit insertion (9 December 2003)・・・・・・・・・・・・・・・・・・・・・・・・・・7

Ⅱ.Looking into the causes of fuel supply system mulfunction

1.Circumstances of mulfunctioning・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・8

(1) Outline of propulsion system・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・8
(2) About the operation for Mars transfer orbit insertion・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・8
(3) Grasping the telemetric data and analysis・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・9
(4) Operation after telemetry and status of LV2・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・10

2.History of selecting LV2 valve for Nozomi・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・11

(1) History of LV2 valve selection・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・11
(2) Inspection contents of LV2・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・13

3.Estimated causes of the mulfunction・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・15

(1) Fault tree analysis (FTA)・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・15

-ⅰ-

(2 Candidates for faults・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・15
(3) Estimated causes of the mulfunction・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・17

Ⅲ.About the mulfunctions in the coms and thermal control systems

1.Circumstance of these occurrences・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・18

(1) Outline of the power system・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・18
(2) About the operation between the times of contact loss prior to the mulfunction and mulfunction day・・・・・・・・・・・・・・・・・18
(3) Space environment on the day of mulfunction development・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・19
(4) "1 bit coms" and grasping of the probe status by autonomous function・・・・・・・・・・・・・・・・・・・・・・・・・19
(5) Grasping the status thanks to the operational recovery after fault development・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・20

2.Estimating the causes・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・22

(1) Fault tree analysis (FTA)・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・22
(2) Causes of the short circuiting・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・23
(3) Estimating the causes of mulfunctions・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・25

Ⅳ.For the future

1.For the future fuel supply systems・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・27

(1) Measures to be taken in valve selection・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・27
(2) Measures to be taken in satellite operation・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・28
2. Measures to be taken in coms. and thermal control systems・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・29
(1) Measures by seperating out the faults・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・29
(2) Development of parts which will not develop latch-ups・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・29

3.Reflecting into the design philosophy of future science satellites・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・30

(1) Design changes・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・30
(2) Ground tests・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・30
(3) Imported parts・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・31
(4) Fault seperation・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・31
(5) Software operation in contingencies・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・31
(6) Policy on future deep space missions・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・32

Ⅴ.graphics and charts and tables・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・34

‐ⅱ‐

Ⅵ. Glossary and abbreviations・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・78

(reference 1) Finding the causes of the failure of Nozomi and future measues to be taken・・・・・・・・・・・・・・・・・・82

(reference 2) Members of SAC (I will not be translating this reference, P)・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・83

(reference 3) Schedule of the investigation meetings・・・・・・・・・・・・・・・・・・・・・

(end of the contents list page)

P

Posted by: Phil Stooke Oct 24 2011, 11:04 AM

Thanks for doing this. It is very interesting.

Phil Stooke


Posted by: nprev Oct 25 2011, 01:51 AM

Yes indeed, THANK you, Pandaneko! In my opinion, what you're doing here is one of the most valuable things that multilingual UMSF people can do: provide translations of technical documentation, which of course is rarely affordable for individual projects or even national space agencies.

Posted by: pandaneko Oct 25 2011, 08:58 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

Page 1: preliminary (omitted)

Page 2:

1.Outline of the satellite

(1) Objectives set for Nozomi

Nozomi was conceived with its main objectives of looking into the direct interaction between the solar wind and Maritian atmosphere/ionosphere. In addition, Nozomi was conceived as the first planetary probe of this country trying to look into solid planets and serving as an engineering test satellite for future deep space missions.

(2) Outline of the satellite

Nozomi is a spin stabilised satellite with a high gain antenna fixed atop a pentagon shaped pillar boby. It is a small satellite, with its inertial mass of 540kg (of which 280kg is fuel) and the total height of 2.4m (from nozzle tip to end antenna) and diameter of 1.6m. It carried 15 different instruments (35kg inluding an extensible structure). Nozomi's ultimate shape (imagined) in its Mars circulating orbit is shown in the graph I-1-1.

(3) Outline of the knowledge obtained before insertion abandonment and its instruments「

Nozomi carried 15 different instruments such as an extreme ultraviolet imager, ultraviolet imager, ion energy spectrograph etc. Main findings using some of these include the world first image of Earth's plasma sphere and interstellar materials measurements. Altogether, 10 out of 15 instruments were actually operated.

In addition, Nozomi had 8 engineering objectives required for future deep space missions such as ultra high precision in orbit determination and autonomous control of the probe. These naturally form an important basis for our future deep space missions.

For your information, the outline of observational results, list of instruments, achieved engineering objectives, and the positions of each instrument on board are shwon in tables I-1-1, I-1-2, and schematics I-1 and I-2.



2.Background and history of its development (what a strange place for this to be!, P)

end of page 2

Posted by: pandaneko Oct 26 2011, 09:26 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

Page 3 (I believe)

(1) History of Nozomi development

It was decided in 1991 that we will start developping, with interplanetary missions in mind, the M-BV series of solid fuel rocktes. This marked a contrast with the earlier M-3S2 series of solid fuel rockets in that the launch capacity will increase from approx. 770kg to approx. 1800kg (ability for insertion into the lower earth orbit) and meant that planetary missions were suddenly within the grasp of scientists. Nozomi was thus conceived.

Since interplanetary missions require a large amount of launch energy it was decided to make use of planatery swing by method with the Nozomi mission. For your information the table I-2-1 shows the range of mission targets which became possible as the result of M-V rockets.

(2) Science targets of Nozomi

Nozomi's main aim was to look into the direct interaction between the solar wind and the upper atmosphere of a planet. About whether its target is to be Venus or Mars the then Institute of Space and Astronautical Sciences (ISAS) made an extensive investigation taking into the account the voices of scientific communities interested in planetary science.

Based on this it was finally decided that Nozomi's science target was to be Mars taking into the account the following points.



① There was very little observational result at that time.

② Earlier Viking lander (note 1) showed that Martian atmosphere extended to such a height that could not be fully explained by the pressure balancing of the atmosphere and the solar wind.



③ Earlier Phobos 2 probe's (note 2) observation suggested that an extremely large amount of oxygen ions flew into the interplanatary space which cannot be ignored in our reasoning of the evolution of Mars. For your information the table I-2-2 shows the status of missions to Mars by other contries at the time of Nozomi's planning.



(Note 1) : Viking Lander

This is a NASA Mars lander. Two of them landed on Mars in 19XX (I am afraid I do not have a year designation conversion table for this period ready for translation, P) and offered direct data on Martian atmosphere and ionosphere.

(Note 2) : Phobos 2

Former Soviet Union's Mars observer and stayed in orbit for 2 months from January 19XX (ditto, P) and discovered an extremely large amount of oxygen ions escaping Mars.

end of page 3

(in the earlier page I made a mistake, extensible should have been extendable, i.e., telescopic)

P


Posted by: pandaneko Oct 27 2011, 09:09 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference


(3) Nozomi's design philosophy

Nozomi was designed to be launched in 1997 and its development and manufacturing spanned the four years starting in 1993. Its development was based on the following points.

① It should carry world first class instruments which can expect maximum returns.

② In order to maximise its scientific returns Nozomi should be designed to be proactively international.

③ Most reliable engineering technologies should be employed to secure its mission.

④ In manufacturing the probe only reliable and trustworthy parts and instruments should be procured.

⑤ Since the launching rocket is to be an M-V type the maximum weight of the probe should be kept within 530kg (later increased to 540kg thanks to the improvement of the rocket capability).

With respect to the points 1 and 2 above we are pleased to note that overseas groups were providing 4 instruments, ultrahigh stable resonator, image compression chips with world top class obervational capabilities.

In addition, all the data obtained by its mission was, ultimately, to be made available to all scientists across the world.

About the point 3 above, we adopted the dual liquid propulsion system because we concluded that aerocapture (note 3) and electric propulsion system (note 4) were still technically unreliable.

About the point 4 above, the valves that were right for the Nozomi specs were not produced by domestic manufacturers. This meant that we would have to use overseas parts with restrictions on the provision of technical indformation. For this reason, we decided that we should be sufficiently careful in order to ensure that they met our requirements in terms of reliability through quality assurance tests and related tests and inspections.

About the point 5 above, we reflected this weight limitation in our probe design (to be discussed later) and reduction of the weight of the probe was concretely put into action.


(Note 3) Aerocapture

This is a technique by which atmospheric pressure resistance is used to reduce the velocity of the probe for orbit insertion. This will allow a very large amount of reduction in fuel consumption. However, in the case of Mars the precision required for deviation from an optimum height is about 5km and is quite chaleenging. In addition, the target height will also vary according to the state of the Mars atmosphere at the time of velocity reduction and also the probe must be protected against heat.

(Note 4) Electrical propulsion

Artificially produced plasma is accelerated by high voltage and released into space for propulsion

End of page 4

(I am trying to be as accurate as possible in my translation. However, if anybody has any questions or require further clarification I will be very pleased to re-translate the bits in question. P)


Posted by: PaulM Oct 27 2011, 11:52 AM

I understand that the reason for the final failure of the Nozomi mission was as follows:

"In April 2002, on its way to Mars, NOZOMI had experienced a very strong solar energetic proton event associated with a strong solar flare. This caused a short circuit in one of the subsystems and a loss of telemetry signal, which made the Mars orbit insertion impossible."

http://www.spaceref.com/news/viewpr.html?pid=13182

I also understand that Spirit and Opportunity survived the same solar flare without suffering any problems. I have always presumed that the reason for this was either that Japan did not have access to the same space certified components that JPL had access to or that Japan did not have JPL's understanding of designing space hardware in a radiation tolerant way.

Posted by: Paolo Oct 27 2011, 12:09 PM

the reason why Spirit and Oppy survived the April 2002 solar flare so well was because they were still shielded by the Earth's magnetosphere... wink.gif

Posted by: pandaneko Oct 28 2011, 09:43 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for quick reference

page 5

(What is immediately after this is the continuation from page 4. I am sticking to the original layout so as not to create confusion to those who may attempt their own translation)

It has higer efficiency compared with the weight of the fuel required. For your information this method of propulsion is one of the targets for testing with Hayabusa spacecraft which was launched in May 2003.


(4) Nozomi design philosophy


Nozomi design is based on the following considerations.

① We pay utmost attention to reducing the weight of the satellite.

② Since there are instruments which are very susceptible to surface (electrical) potential we should take an even more precaution in earthing them compared with usual measures taken for preventing accidnets due to charging and discharging.

③ We should have a certain criteria/standard for the electromagnetic noise leve so as not to affect instruments on board.


④ We should not use potting materials in order to prevent instrument deterioration through resulting contamination. In order to put into effect the point 1 above following improvements were made.


・With these science satellites we are expected to obtain world top class results and for this reason it will be desirable to keep as much ratio by weight of the instruments against the total weight of the satellite. Therefore, while retaining the reliablity standard comparable to that enjoyed by other earlier satelllites the results of the STRAIGHT project (note 5) were put into use with Nozomi. These included surface mounting of parts, batteries using nickel/hydrogen cells, semiconductor data recorder using large capacity memories etc.


・While the satellite was made as light as possible reliability assurance was of paramount importance and for this reason a redundant system was employed around the CPU relating to attitude and orbit control (AOCE). For your information the bus system design gave a higher priority to weight reduction rather than fault seperation ability given that the system used radiation tolerant parts and other parts for space use, all pointing to much lower possibility of mulfunctiioning.


・ Compared with the earlier central power distribution method a dispersed power distribution method was employed for the first time with a science satellite (17 lines).


・With the observation system a radical reduction in weight was pursued by taking into account the relative merits in reliability against on board weight and this included, for instance, a unified electronic control looking after more than one instrument.

(Note 5) STRAIGHT: Study on the Reduction of Advanced Instrument Weight

This is a project looking into the next generation probe technologies.

end of page 5

P

Posted by: pandaneko Oct 29 2011, 09:39 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

I realise I made some omissions about redundancies with onboard computers in the last page. The passage should have read;

the systems around CPU relating to data handling unit (DHU) and AOCE adopted "waiting" redundancy and the register for the common systems had a tripple redundancy incorporated in the system

("waiting" bit, I am unsure. I just simply translated direct from the original sentence, P)

page 6

From the viewpoint of point ② above all of the layers of the thermal blanckets (MLI) well over 100cm in length were earthed. In addition, conducting treatment to the cover glass of the solar cells and earthing were carried out. We also adopted approapriate design for keeping the instruments full capacity as outlined in ③ and ④ above.




(5) Further weight reduction due to launch postponement

Nozomi's launch date was sifted due to the delay in M-V development. It was decided in 1994 that the launch will be postponed to 1999. The most desirable launch timing was 1997 from the perspective of the satellite weight. The new launch timing of 1999 meant that the weight will increase by 30kg, coming from the fuel and this immediately meant that the dry weight of the satellite will have to de reduced by a further 20kg from the original design (10kg was to be covered by the increased rocket capacity).

Given all these we decided that an alteration to the then adopted shape of Nozomi and total reconsideration of the insturment layout was too risky at this stage and that the two years arising from the delay will have to be used to come up with further reduction in weight of individual components without changing the interface with other parts.

One such example includes the power supply to the heater control circuit (HCE) and data recorder (DR). Originally, the power to these was to be supplied from a dedicated source. However, they consumed a relatively small amount of power and the source of power was thus changed to the common systems power source (CI-PSU) and the number of power sources itself was also reduced from the original 17 to 15.

Individual weight reductions achieved during this period and their effects are listed on the table I-2-3.



3.Outline of the history of the failure of Mars orbit insertion of Nozomi

(1) Occurrence of mulfunction in the fuel supply system (20 December 1999)

Nozomi was launched on 4 July 1999 from the then ISAS Kagoshima space centre by an M-V 3 rocket. A mulfunction was detected in the fuel supply system during the escape from the earth gravity on 20 December 1999 and Nozomi failed to produce required propulsion. As a result, it became impossible to contemplate an insertion into Mars orbit during the middle of October 2000.

Therefore, it was decided to make use of 2 earth swingbys and reach Mars after a delay of 4 years some time in late December 2003 to early January 2004. This was a further change of plan.

For your information, the orbit plan after this change is shown with the schematic I-3-1.

end of page 6

Posted by: pandaneko Oct 30 2011, 09:03 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 7

(2 ) Occurrence of mulfunction in comms. and temp control systems (25 April 2002)

Nozomi had been flying without hitches atfer that. However, on 25 April 2002 a mulfunction developped in the comms. and temp control systems and it only became possible to receive beacon signals. At the same time it was no longer possible to control heaters. Because of this the fuel froze and it meant that we were unable to use the main and auxilliary engines.


(3) Operation designed to recover from these troubles

For above reasons we tried recovery operation from 15 May 2002, but we did not get anywhere. For your information, by end August of the same year the use of heat generated from onboard instruments and others led to the frozen fuel reaching the melting temp and it became possible to use the auxilliary engines at the start of September.

Therefore, we attempted the 1st earth swingby on 20 December 2002, the 2nd earth swingby on 19 June 2003 and these were both successful and we were able to put the probe into the Mars transfer orbit.

However, parts of the piping system which were meant to supply fuel to the main engine remained frozen and the main engine remained unusable. The temp change history from late July to end September measued at temp measurement points is shown on the graph I-3-2.

(4) Giving up of hope for Mars circulating orbit insertion (9 December 2003)

It would have been possible to place the probe into the Mars circulating orbit had the main engine recovered from the freeze before insertion into the transfer orbit. We continued recovery operation from 5 July 2003. However, above mentioned function did not come back before 9 December 2003 and the hope of Mars circulating orbit insertion was lost.

For your information, an orbit change to avoid the possibility of collision with Mars (approx. 1% possibility) was conducted during the night of 9 December using the auxilliary engines. Following this operation Nozomi passed the point above Mars surface at approx. 1,000km on 14 December 2003 and it is assumed that Nozomi finally escaped from Mars gravitational field by 16 December 2003.

end of page 7

P


Posted by: pandaneko Oct 31 2011, 09:38 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 8

Ⅱ.Trying to clarify the causes of mulfunction in the fuel supply system

1.How mulfunction occurred

(1) Outline of the propulsion system

Nozomi's propulsive system was meant for insertion into Mars transfer orbit before reaching Mars, orbital changes for insertion into Mars circulating orbit, and pointing the antenna towards the earth once in Martian orbit and consisted of the Orbit Maneuvre Engine (OME) with a 500N class dual liquid thruster and the Reaction Control System (RCS) with single liquid thrusters for atitude and orbit control.


Nozomi's propulsion system and main specs are listed with the schematic II-1-1 and the table II-1-1.

Nozomi's piping system was typical satellite propulsion system and its OME engine produced propulsion by burning the hydrazine from the fuel tank with NTO. In so doing the fuel and the oxidiser are pushed out by the helium gas into the engine. Both hydrazine and NTO are liquid and are highly reactive when mixed together with self-igniting capability and for that reason the engine does not have a special ignition mechanism as such.

(2) About the operation at the time of insertion into Mars transfer orbit

Nozomi was launched by an M-V 3 solid fuel rocket on 4 July 1999 and went through various orbital adjestments. During the unseen period (tracking station unable to see the satellite in line of sight) on 20 December of the same year an automatic control was executed to put the satellite into the Trans Mars Orbit (TMI).

It was during this sequence that the orbital change by the OME did not attain the required velocity increase. Time sequence of this event is shown on the schematic II-1-2.

1) Status at the time of TMI

According to the US JPL flash report issued around 12:00 (UTC) on 20 December 1999 there was a shortfall of velocity by some 100m/s against the required delta V of 423.22m/s

2) Operation during the visible period immediately after TMI

(part of what follows actually spills out onto page 9, but I am translating the whole paragraph for ease of reading)

The visible operation immdeiately after the TMI (around 17:00 on 20 December (UTC)) indicated that the onborad intergrated value was 327.1m/s as the velocity increase, close to JPL flash report. At the same time the pressure sensoer P4 indicated that the pressure of the oxidiser tank alone showed an abnormal value of 8.3kgf/cm (0.8MPa). (Schematic II-1-3)

end of page 8

P

Posted by: pandaneko Nov 1 2011, 09:19 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 9

(what follows follows directly from the last para on the last page)

For this reason a command was sent (18:20 UTC on the same day) to the oxidiser gas system latching valve LV2 to open it (schematic II-1-1) which is instaled as a non-reversible valve in the pusher gas piping system for the oxidiser tank. As a result we obtained following information and we concluded that the propulsion system returned to normal.

・ We obtained confirmation that the status of LV2 was open (schematic II-1-4).

・ Accelometer detected a vibration which seemed to have come from the functioning of the LV2 valve and the gas flow following it (schematic II-1-5)

・ It was confirmed that the oxidiser tank pressure recovered 15.1kgf/cm (1.48MPa) (schematic Ⅱ-1- 2(1.48MPa)4)

(about this reference number, I am utterly unsure and we will have to wait until tommorrow if above is right. This is a result of my copy/paste and 1.48MPa sneaked into this reference and it ought ot be immdeiately after the kgf and I cut this out and put it in the right place as you can see here. However, if I cut out (1.48MPa) from the reference I will be left with a ridiculous ref number. It cannot be 24, and I suspect that it is actually 4, but there is no easy way for me to find out without losing what I have done by now)



(3) Grasping the events from the telemetry data

1) Telemetry data analysis

Analysis of the telemetry data relating to the propulsion system obtained during the period immediately after TMI indicated what follows.

a) Attitude change (at the time of the latching valve beeing open)


・Attitude change so that OME points in the velocity increase direction and a spinup (10 to 25 rpm) for securing attitude stability for when OME functions, both of these were activated by the RCS engines


・ A series of sequence until liquid and gas system latching valves (LV6, LV5, and LV2) indicator indicated open status were normally executed.


cool.gif Functioning of OME

・The pressure of the oxidiser tank continued to fall without staying constant throughout the period in which OME burnt, from 14.6kgf/cm (1.43MPa) to 7.1kgf/cm (0.70MPa) at the time of OME stopage (schematic 2II-1-6).

(this makes me think above might have been 2II-1-4, P)


・ Acceleration also decreased from 0.97m/s to 0.76m/s (schematic II-1-7, 22) (again, unsure about this 22, P)


・ Integrated value of acceleration did not reach the required value of velocity increase. However, the duration of OME firing reached the maximum operational 397.5 seconds for safety and the firing was automatically terminated. It meant that there was a shortfall of 100m/s against the required value of 423.22m/s as the reached value was 327.1m/s.



c) Attitude change (at the time of latching valve close)

end of page 9

P

Posted by: pandaneko Nov 2 2011, 09:22 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

(I realise that I forgot to look at the earlier reference number. I will deal with it seperately.)

page 10

・After the termination of OME burn a close command was sent out following the sequence to liquid and gas system latching valves (LV2, LV5, and LV6) and the indicator showd "closed".

・After this a series of sequence including spin down and attitude change was excecuted without any problem.

2) Mulfunction situation

From these points above the mechanism of insufficient delta V is estimated to be as follows.


① Despite the fact that LV2's indicator is showing open status not enough pusher gas is being supplied to the oxidiser tank. From the relationship between the estimated value of empty tank volume change and and pressure change it is estimated that the supplied amount was 2% of the LV2 complete close case.


②Oxidiser tank pressure decreased.


③ Not enough oxidiser was supplied to OME, leading to an inefficient burn, resulting in OME propulsion drop.


④ Because of this unexpected propulsion drop OME firing was terminated as the maximum burn time was reached before attaining the planned delta V.


3) Where faults took place

Insufficient delta V during TMI was due to the decrease in the capacity to supply pusher gas to the oxidiser tank. Possible cause of this decrease is thought to be hitches relating to the check valve CV2 and the latching valve LV2 in the propulsion system. In this particular case it has been shown that this insufficiently opened passway occurred not with CV2 but with LV2 from the following reasons.

① The pressure value returned to normal as a command was sent out from the ground to open LV2.


② The output of the acceleration meter indicated that there was a shock as the LV2 valve opened and also there was a vibration as the gas flew as a result.


(4) Operation after this and the status of LV2


1) Evaluation of the status of the propulsion system

In order to make up for the insufficient delta V during TMI two additional corrective OME burns (TMI_C1, TMI_C2) were conducted and these were carried out normally. We also carried out an evaluation test on the OME propulsion and supply system in order to check on approapriateness of the corrective burns and subsequent health of the propulsion system and we are satisfied that propulsion system returned to normal.

a) Evaluation of OME propulsive power

We obtained, from the acceleration of OME burn and tank pressures data, OME propulsive power and its specific impulse as well as the amount of propellant flow. These characteristics were then sorted out according to the regulator pressure (P2). The result showed that during the subsystem burn tests (SFT) and during the early stage after the launch TMI_C1 and TMI_C2 both showed almost similar characteristics, meaning that there was no trouble with the OME burns. (Schematic II-1-8)

end of page 10

(actually, part of the very last paragraph spills into page 11, P)

Posted by: pandaneko Nov 3 2011, 09:36 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

for your information the reference for the (2) on page 9 is (schematic II-1-4)


page 11

cool.gif Evaluation of OME supply system

We examined, in terms of OME functioning time, the pressure loss ratio of the gas and liquid systems due to OME burn during SFT and after the launch. All other indicators except that for the oxidiser system during TMI showed almost similar behaviours and we did not find any trace of characteristics change due to material deterioration and comcluded that the supply system was healthy. (schematics II-1-9 and II-1-10)

2) Operation of LV2

With Nozomi's propulsion system LV2 and CV2 prevent the reverse flow of vapour from mixing with hydrazine and leading to explosion. For an explosion to actually take place the vapour must condense upstream and a certain minimum amount must stay there.

However, it was confirmed that there was enough electrical power available from the track record of operation and that it was possible to maintain, due to the relaxation of the allowable tank temperature range, the temperature of the valve module A (VM-A) (schematic II-1-1) 10 degrees higher than that of the NTO tank.

Therefore, we concluded that even if LV2 is open we will be able to be free from above trouble with this newly acquired temp control leading to a dual safety mechanism with the use of CV2.

For this reason, the operation thereafter was such that both LV1 and LV2 were kept open all the time so as not to cause LV mulfunctioning.


2. History etc. of selecting LV2 for Nozomi

As shown above it became clear from the analysis of the telemetry data that the oxidiser gas system's latching valve LV2 developped a mulfunction. This LV2 in question had been selected and passed the verification test as shown below.

(1) History of LV2 selection

1) Method of valve selection

Valves for space use are little produced domestically. Therefore, in the case of Nozomi valves that met neccessary specs were procured from overseas. With this particular valve there was know-how related subtle technical information relating to its design and manufacturing. Therefore, details of its fine structure were not available and it was also prohibited to disassemble the valve in Japan.

LV2 was procured from a US manufacturer with excellent track records in space use. It was converted by the manufacturer, at the request of the then Institute of Space and Astronautical Sceinces (ISAS) so that it conformed to the structure of Nozomi by adding a status monitor (LVDT).

(from here on the remaining text spills into page 12)

LV2 is based on the combination of two components which have substantial flight records. As mentioned above its delails are not available and what was done was to investigate the potential imaginable risks invloved upon selecting this particular valve. Detailed information of this investigation is shown in the table II-2-1.

end of page 11

P

Posted by: pandaneko Nov 4 2011, 09:50 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 12

2) Building in of LV2

We had debated about whether we should carry LV2 on Nozmi and our conclusion was that we should do so from the viewpoint of preventing a massive reverse flow of oxidiser vapour. LV2 is placed in the propulsive system at the downstream side of the regulator after the forking out of fuel and oxidiser pipes and between the check valve CV2 and the oxidiser tank (schematic II-1-1). Its function is to prevent the mixing of fuel and oxidiser at the gas side of the system.

With this particular propulsive system we are employing a dual redundancy system of accident prevention together with the CV2 placed in the upstream. This dual redundant system with LV2 and CV2 does not mean we did not have confidence in any of these valves. Rather, it was employed to increase reliability to an even higher stage against the reverse flow of vapour which might lead to a fatal accident, damaging the probe.

During the development stage of Nozomi in 1994 an accident occurred to a US Mars probe (Mars Observer) and it was lost. Its cause was estimated to be an accidental mixing of oxidiser and fuel vapours in the gas system pipeline. Reverse vapour flow is likely to lead to a total loss of a satellite and this point was also taken into consideration.


3) Adding LVDT

About whether we should install a valve status monitor LVDT with the LV2 our conclusion was that LVDT constituted an important source of information for the steady operation of LV2, reducing the pressure on the operating team and the possibility of human errors.

In the case of Nozomi, on the other hand, there was a factor of influence at the time of valve selection arising from the merger and acquisition of the US valve manufacturer in that it meant the addition of LVDT to a valve without a status monitor but with an ample proven record of operation.

Generally speaking the reliability evaluation of a design change to an operationally proven part has not been established just as in the case of newly developped parts. However, our judgement was that this was going to be based on an operationally proven valve and the design change was going to be introduced by a reliablbe US manufacturer and consequently the risks involved in this design change were small enough. For this reason we selected the LV2 with LVDT added to it.

As shown in the table II-2-1 the risk of valve mulfunction after the desing change was thought to be similar to that of operationally proven valves.

end of page 12

P

表Ⅱ-2-1に示すように、バルブ開閉ができなくなるリスクでは、改造品といえども、そのリスクは搭載実績品と同様であると判断されていた。

Posted by: pandaneko Nov 5 2011, 09:30 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 13


4) Structure of LV2

LV2 structural outline is shown by the schematic II-2-1. Inside the valve there are 2 electromagnets (one each on the right and left of the schematic) and they activate the inner piece (some kind of intermidiate piece, P).

いての独自の追加試験の検討
By letting an electrical current flow through the close side electromagnet (on the left) the inner piece is pushed in and the flow is stopped (state of the schematic) and by letting an electrical current flow through the open side electromagnet (on the right) the inner piece will leave the plug (or seperate from the plug, P) and in that state there occurs a small pressure difference between the up and down streams and this differential pressure pushes the plug and the flow will start.

Also, as shown on the schematic II-2-1, LVDT on the right will monitor the open/close status of the valve by detecting the position of the inner piece. Those original valves with track records of being used with satellites did not have this LVDT. Design change by adding this LVDT meant that the plug and the inner piece were seperate items.

This arrangement of having a seperate structure had been proposed by the US valve manufacturer in an answer to the concern that the addition of LVDT meant a longer inner piece and a resulting small positional erorr might influence the open/close operation of the valve.

(2) Contents of LV2 verification

1) Verification method for LV2

Starting from valves used for scientific satellites those valves used for space use are almost all imported from overseas. Consequently, verification of the selected valves are carried out by those overseas manufacturers and the Japanese procurers. In the case of Nozomi too, this verification was carried out by both US manufacturer and in Japan as shown below.

a)LV2 verification method

① Contents of verification requested by the Japanese side to the US valve manufacturer

・ Verification of design validity

・ Verification of manufacturing validity concerning the shipped flight items

・ Flight track records

Flight tracking records include, if possible and approapriate, concrete mission names and usage. We regarded the usage as important because if the past programmes' mission duration and environment had been different it might be difficult to count it as a proven track record.

② Contents of verification conducted by the Japanese side

・ Confirmation of the justification of the verification methods for each of the items which relate to the verification of the validity of design and manufacturing

(up until here, translation from page 13, but the circle 2 continues into page 14 as follows, P)

- 14 -

・ Carrying out a consolidated system test in the state in which the items were actually built into the satellite

・ Investigating into the possibility of our own additional tests with those items whose flight tracking records could not be confirmed and where details of the verification methods were not available.

end of page 13

P

Posted by: pandaneko Nov 6 2011, 09:03 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 14

cool.gif History of LV2 tests

Confirmation tests of LV2 were carried out in two major parts. One is the design quality confirmation test where another test piece different from the flight piece was fabricated and offered to testing. Second is the confirmation test for flight model manufacturing approapriateness, which is conducted on the flight model. Their outlines are shown below and the ground test history of LV2 is carried on the table II-2-2.


① Design quality confirmation test

This is the test whereby design validity is confirmed. In addition to the test conducted by the US valve manafacturer another test was carried out in Japan.

The valve manufacturer conducted their own test using two test pieces, LV2 and a similarly designed LV1 together with HLV. In Japan we used a spare part, common to both LV1 and LV2, and conducted a confirmation test on the adaptability to the oxidiser (NTO) environment.

We had been given a report from the manufacturer that the valve in question had resistance to NTO and ours was carried out seperately to confirm this report using the flight piece of the valve. The number of valve actions during this test is shown on the table II-2-3.

② Confirmation test for the manufacturing validity of the flight model

This was the test conducted on the flight model. Confirmation was sought with the part built into the satellite system for its health. Below is the number of delivered pieces.

・LV1、LV2 : one each
・LV1、LV2 common piece: two
・HLV: one and HLV spare part: one

2) Action history of LV2

The number of counted valving actions during TMI with the valve in question was 42nd since the day of the delivery and 6th from the day of launch. It was confirmed that all valving actions prior to that had been normal. LV2 action history is shown on the table II-2-4.

end of page 14

P

Posted by: pandaneko Nov 9 2011, 09:23 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 15

3.Estimating the causes of mulfunction

(1) Fault Tree Analysis (FTA)

We conducted an FTA with the following events at tree top in order to estimate where LV2 mulfunction occurred.

・ A command had been sent from the ground for opening of LV2 and LVDT did show that LV2 was open. However, in reality the opening was minimal and the flow rate was very small. The result of this FTA is shown on the table II-2-5. We at JAXA did exchange information with the US valve manufacturer after the accident. However, as mentioned earlier, the information relating to the valve structure etc was limited in availability.

We summarised the possible mulfunction candidates based on the FTA analysis as shown under (2) below.


(2) Possible mulfunction candidates

1) Bad sliding motion of the plug

One strtucural problem with LV2 is that the plug and the inner piece are separated physically. In addition, there is a possibility of the material surface of the sliding component inside the valve suffered from a fletching wear due to the valve motion and this led to the issue of valve material's compatibility with the oxidiser.

It is thought possible that these two factors might have led to bad sliding motion of the valve.


(note 6) : fletching wear

surface damage arising from repeated slidings at the sliding area


a) Valve structure


We did conduct a repeat evaluation on the past flight records and had confirmation that valves with this particular material had flown many times in the past. However, these valves had a monostructure of the plug and the inner piece and the valve was forced to activate with an electromagnet.


With respect to the valve that we used its (valve) open mode was similar to that of so called check valves in that it opens passively when there is a diffential pressure before and after the plug. The driving force arising from this differential pressure was smaller compared with the force originally ensured by an electromagnet and the valve could have suffered if the plug's sliding force resistance (note 7) had increased.


(note 7) : sliding force resistance (please note that this sentence astrides pages 15 and 16)

The resistance against the sliding motion involving two objects in contact. If this force becomes large

- 16 -

then objects become harder to slide against each other, requiring a larger force for sliding.

end of page 15

P

Posted by: pandaneko Nov 10 2011, 09:51 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 16

cool.gif oxidiser resistance of the material

Material combination of the sliding parts is austenite (spelling unsure, P) stainless steel at the sliding area of the plug, and ferrite staeinless steel for the valve body. Ferrite stainless is magnetic by nature and is used extensively with electromagnetically activated valves. On the other hand it is slightly less resistant against NTO compared with non magnetic austenite stainles steel.

It is thought possible that fletching wears would have led to corrosion of the valve body area in question after being filled with NTO, itself further leading to an increase in the sliding friction.

2) Gritting of the plug into the opening area

It is thought possible that the plug which had been pressed against the opening area for a long time might have gritted into the opening, making the plug less mobile. It is also thought that from the status of the lowering of the oxidiser tank pressure a small amount of helium gas was still being supplied to the oxidiser tank and that in the event of plug gritting this might have led to , with a high possibility, the complete closure of the sealing area.

With respect to LV2, the duration in which it was kept closed immediately prior to TMI operation was not especially long compared with similar operational duration with other launches. For that reason it is thought that LV2 did not suffere from the same trouble. For your information the history of LV2 use in operation is shown on the table II-2-6.


3) Plug mis-allignment

The valve in question had been subjected to Quality Test (QT) and undergone more than 1,000 times of open/close operation. All this was monitored using LVDT monitor and also pressurised heilum gas flow confirmed the valving actions. Also, quantitative flow volume tests had been put into action before and after this open/close test and it was confirmed that everything was normal as designed.

For these reasons we consider that there was no design problem with the clearance between the valve body and the plug.

In order for this particular mulfunction to take place we could suspect, as its cause, bad manufacturing of the valve. However, the valve in question operated normally 42 times before mulfunction including the period immediately after launch and there was no sign of bad manufacturing.

Furthermore, the valve continued to function normally even after the occurrence of the mulfunction and we believe that the valve is not a culprit.


4) Glitching by foreign pieces

The diamterwise clearance between the plug and the valve supporting body is such that if foreign pieces larger than the gap migrate into

栓とバルブ本体の直径クリアランスは、より大きい異物がバルブ内に入り込むと噛

- 17 -

the area inside the valve they may cause gritting there. However, the pre-launch gas filling was done using a filter whose mesh is smaller than the clearance dimension and it is thought unlikely that there were foreign pieces of that size present inside the piping system and that foreign pieces were the culprit.

Also, generally speaking, once gritting takes place it is rare for the system to resume normal operation immediately. However, in this case we are looking at the function of LV2 returned to normal after the hitch and consequently it is thought highly unlikely that this phenomenon happened to LV2.

end of page 16


Posted by: pandaneko Nov 11 2011, 09:09 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 17

5) Temporary immobility (or solidification) by material growth (or some kind of crystal formation?)

If there had been residual water inside the propulsion system it could have been possible that the reaction of fuel and oxidiser led to the formation of ammonium nitrate. However, this possibility has been discarded as extremely low for the following reasons.


・ dryness at the time of propellant filling was very good (condensation temperature being minus 55 degrees C or below)


・ Had there been a mixing with fuel the check valve upstream would have caused mulfunction


・ It would have shown up in a short span of time (a few days)


(3) Result of estimating for the causes of mulfunction

If we are to summarise what we have been talking about so far, we think that the causes of LV2 mulfunction are due to, as shown in 1) of (2), the fact that the valve was susceptive to increased sliding friction of the plug given that the valving was powered by the differential pressure by the seperate inner piece and the plug

and also the fact that the sliding surface caused a fletching wear leading to corrosion by the oxidiser environment, further leading to an inceased sliding friction.

That is to say that the multiplier effect by these two factors was the most likely cause of the failure.

end of page 17

P

Posted by: pandaneko Nov 12 2011, 09:38 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 18

Ⅲ.About the mulfunctions of comms. and thermal control systems

1. Environment in which mulfunctions took place

(1) Outline of the power source system

Unlike all other scientific satellites which had adopted a centralised power source Nozomi was the first satellite to use a decentralaised power source. Within the Nozomi power system there were 15 power sources and one of them was the Common Instrument Power Supply Unit (CI-PSU) which was used to supply power to a multiple number of commonly used systems (equivalent to power source 2 in fig. III-1-1).

This CI-PSU receives power from solar cells and batteries placed on the primary side and supply power to 10 secondary side subsystems such as the telemetry command interface (TCI) for the X-band transmitter (TMX) and the heat control circuit (HCE).

For your information, the structure of CI-PSU is shown by the schematic III-1-2 and the table III-1-1.

(2) About the operation from the time of losing signals until the day of mulfunction taking place

The mulfunction was first detected during the operation on 25 April 2002 and the location of Nozomi at that time is shown by the schematic III-1-3. Also, the operational sequence from a day earlier (24 April 2002) prior to losing signals until the day of detecting the mulfunction is shown on the schematic III-1-4. This operational sequence tells us the following story.


① At 18:05 on 25 April 2002 (UTC) signals came in in the beacon mode despite the expectation that the transmission mode had changed to the telemetry mode (note 8). We then sent a command from the ground so that the mode changed to the telemetry mode, but this was not successful. From all this it is obvious that the status remaining was such that we could not switch the mode.

(note 8) : telemetry mode

mode in which telemetry information from the satellite is carried on the satellite wave

(note 9) : beacon mode

satellite is emitting waves, but these waves are not carrying telemetry information.


② We had anticipated an attitude change (about one degree) at 09:00 on 25 April (UTC). However, from the reception level of the satellite waves on 25 April it is estimated that this attitude change did not take place (fig.19-III-1-5). It is also estimated that the command sent from the ground for the attitude change did not succeed.

From all above it is estimated that the attitude change remained impossible.

end of page 18

P


Posted by: pandaneko Nov 13 2011, 09:04 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 19

(3) Space environment at the time of mulfunction being detected

A solar flare of class X occurred on the western area of the Sun's surface on 21 April 2002 with a magnitude of X 1.5 (X-ray flux of 0.15mW/m in the vicinity of the earth). Nozomi received a direct hit of high energy particles associated with this flare on 22 April. As the strength of high energy particles it was the largest since the launch of Nozomi and it is estimated that it was one magnitude higher in energy than anything that Nozomi had experienced earlier. This magnitude is estimated to be such that you normally expect this magnitude in interplanetary space only once or twice during any one solar period (11 years).

For your information the temporal variation of solar proton monitoring by the device on board Nozomi is shown on the graph III-1-6. Also, the high energy particles strength variation experienced by Nozomi since 2000 is shown on the graph III-1-7.


(4) "One bit comms." and grasping of the phenomenon by the autonomous function etc.

It became possible to obtain the data neccessary for the operation of Nozomi (table III-1-2) by establishing a measurement method using Nozomi's autonomous function (note 10). For instance, if you wish to measure the temperature of the inside of the satellite, the beacon is turned either on or off, depending on whether the temp. is above or below the temp. set by the command sent from the ground. (1 bit comms, hereafter) (grapgh III-1-8)

As a result, it became clear that CI-PSU remained in the state of being off. Also, since the possibility of the primary circuit going wrong is extremely low it is estimated that the protection circuit against excessive current flow resisted the CI-PSU from becoming on.

Under these circumstances we expect following phenomena.


① Since TCI is in the off mode a command cannot be issued to TMX. For this reason, it remained impossible to switch between beacon and telemetry modes.


② Since the heat control circuit (HCE) is in the off mode all the heaters inside the satellite controlled by this device are also in the off mode. For this reason, the temp. of the inside of the satellite decreases rapidly to that temp. which is determined by the heat generated by the satellite, sun angle, and the distance to the sun.

Consequently, as shown by the data obtained (table III-1-2) the inner temp. of the satellite decreased below the freezing point of the fuel and attitude control became impossible.

(note 10) : autonomous function

the function which issues a particular set of commands which have been programmed in advance depending on the inside status of the satellite

- 20 -

(and in this instance, we obtained information by making the satellite execute the command which will turn off the power of the power amplifier of the X-band transmitter).

end of page 19

P

Posted by: pandaneko Nov 13 2011, 09:14 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


With above file I seem to be translating some entries which must be rather obvious to UMSF members. Please put up with this as these reports are meant for the Space Activities Commision (SAC) whose members include usually one civilian in order to reflect the opinions of the lay community. One such member as I recall from a few years ago was a newspaper cartoonist.

P

Posted by: pandaneko Nov 14 2011, 09:04 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 20

(5) Grasping events by recovery operation after the mulfunction

Grasping of satellite status, information gathering for the causes of mulfunction, and satellite operation after the mulfunction was carried out as follows.

1) Confirmation of the health of data handling unit (DHU) and command decorder (CMD)

A command was sent from the ground on 28 April 2002 and we succeeded in powering on and off of the X-band transmitter power amplifier (XPA)(XPA is normally ON). From this we concluded that DHU and CMD were operable normally.

2) Grasping probe status by "1 bit comms." using the autonomous function

During early part of May 2002 we managed to obtain probe status through "1 bit comms." using the autonomous function. As will be shown in (4) we discovered that the common power supply (CI-PSU) was in the state of being OFF and also it could not be made to switch into ON mode and that the satellite temp. was far below the freezing point of the fuel on board.


3 Loss of the beacon waves due to the recovery operation of the short circuited portion


This was the operation on 15 May 2002. By sending continuous ON commands to CI-PSU (about 100 times) we tried to burn out the faulty line, but we ended up in losing the beacon waves during this process. We carried out ground tests in order to find out why beacon waves were lost and we estimated that the beacon was made into OFF state because when TCI is started up it also meant that TMX's ON and OFF commands are simultaneously issued leading to erroneous action of TMX relay circuit.

It was also felt possible that the wrong command issued by TCI (such as TMX ON/OFF) in response to the ON command to CI-PSU might lead to TMX going back to ON mode again. Thus, we carried out beacon recovery operation by sending out a series of single ON commands.

4) Recovery of beacon waves

Beacon waves were recovered on 15 July 2002 after sending to CI-PSU a series of single ON commands (about 7,500 times). This confirmed our estimate shown in (3) above. It also became clear that the satellite power (primary power supplied to CI-PSU) was healthy and that CI-PSU were able to supply secondary power at least for a short period of time.

For this reason, it was thought likely that CI-PSU itself was healthy and that the power OFF state was caused by


- 21 -

the protection circuit against excessive current arising from the short circuiting problem within the secondary devices connected to CI-PSU.

end of page 20

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Posted by: pandaneko Nov 15 2011, 09:07 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 21

5) Defreezing of the fuel tank and RCS thrusters

By the end of August 2002 thanks to the self generation of heat by on-board devices, distance to the sun, and improvements in the satellite attitude part of the propulsion system had been defrozen and in the upper part of September of the same year it became possible to control attitude and try small scale orbital control.

It has been confirmed since then that maintaining of the correct attitude helped to keep the fuel tank, attitude and orbital control thrusters from freezing. Owing to this recovery of attitude and orbital control thrusters we managed to succeed in the 1st Earth swingby operation on 20 December 2002, and also in the 2nd Earth swingby on 19 June 2003.

However, it was also confirmd that recovery of heater function was absolutely vital in defreezing the main thruster (required for orbital insertion around Mars) which was always on the shade side.


6) Recovery operation (operation for recovery of , P) CI-PSU and heater control function

Given that for orbital insertion it was vital to have CI-PSU and heating function back to normal we checked through the gournd tests that a continuous and rapidly-issued series of commands for CI-PSU recovery will not lead to action anomally by CI-PSU.

Based on this we started on 5 July 2003 to issue continuous ON-commands for CI-PSU so as to burn out the troublesome short circuited line on the secondary side. During this operatioh we managed to lose beacon waves. This recovery operation continued until 9 December 2003 without success. We therefore gave up the hope for orbital insertion.

7) Items confirmed through this recovery operation

Following the recovery operation explained as from 1) to 6) above we were able to confirm:

①DHUand CMD were operational normally.

②CI-PSU cannot be made to be ON.

③We cannot switch between telemetry and beacon modes.

④Loss of heating function led to fuel freezing and attitude control could not be achieved.

⑤Primary power supply voltage to CI-PSU was normal.

⑥CI-PSU can provide secondary voltage for a short time only.

From these reasons it was thought that CI-PSU was likely to be healthy and that with a high probability the short circuiting on the secondary device side led to the activation of the over-current protection mechanism, which in turn led to the OFF state of the power supply.

end of page 21

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Posted by: Paolo Nov 15 2011, 06:21 PM

thanks again for the translations, panda! I knew that they had regained trajectory control but I didn't know that the main engine remained unusable

Posted by: pandaneko Nov 16 2011, 09:49 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 22

2.Estimated causes of mulfunction

(1) Fault Tree Analysis (FTA)

1) We conducted a fault tree analysis (FTA) with the fact at the top of the tree that we received no waves despite being in the telemetry mode (TLM_ON). The result of this particular FTA is shown on the schematic (or graph) III-2-1.


① As for the possibility of data processing unit mulfunctioning we discarded it because command(s?) were issued normally and we were able to obtain data.


② As for the possibility of TMX mulfunctioning we discarded it because it fails to explain why we could not change attitudes and also because there was no abnormal current consumption by TMX.


③The fact that TCI power was OFF, that is to say we could not keep CI-PSU to be ON can explain without contradiction why we could not change attitudes. It also explains why we could not swtich between beacon and telemetry modes.


2) We conducted another FTA, following one of the the results of above FTA, that is to say ③of 1) above, with the fact at the top of the tree that we could not keep CI-PSU power to be ON all the time. The result of this particular FTA is shown on the schematic (or graph) III-2-2.

There are three causes we could think of as follows.


① There was an anomally in the function whereby CI-PSU inside the satellite power source (PCU) is turned ON/OFF and this resulted in power not being available to CI-PSU.


② There was a mulfunction inside the primary side of CI-PSU and this meant that although the power was being supplied to CI-PSU the overcurrent protection mechanism worked and CI-PSU could not be brought to be ON.


③ There was a short circuiting inside the secondary side of CI-PSU and although the function of CI-PSU was normal the fact that there was an excessive current flowing downstream meant that protection mechanism activated within a few milliseconds, bringing the CI-PSU to be OFF.


3) Discussions about the result of above FTAs mentioned in section 2)

These are as follows.



As for ① of 2) above this was thought to be unthinkable because all other functions inside PCU were

- 23 -

normal.

(this particular paragraph continues into page 24 and is rather lengthy for it being translated as part of page 23. So, I stop here and will continue immediately after this as page 24)

end of page 23

P

Posted by: pandaneko Nov 16 2011, 09:53 AM

QUOTE (pandaneko @ Nov 16 2011, 06:49 PM) *
above for ease of reference

page 22

2.Estimated causes of mulfunction


- 23 -

normal.

(this particular paragraph continues into page 24 and is rather lengthy for it being translated as part of page 23. So, I stop here and will continue immediately after this as page 24)

end of page 23

P


I am confused about this myself. I will look at this tommorrow and try and do correction.

Pandaneko

Posted by: pandaneko Nov 17 2011, 10:27 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

Paolo, I am so glad my translation is being of help with your work! What was strange about yesterday's translation, I had a look at its original. My conclusion is the number 23 towards the end should have been 22, as simply I was translating the bulk of page 22. Having said that I am still feeling very uneasy because I did not type this number 23 myself. I was simply overwriting the copy pasted from the original. Anyway,

page 23

As for ② of 2) it might be thought of arising from the FET (field effect transistor, I think, P) switch failure for DC/AC conversion or IC failure for controling the pulse widths in the primary system (PWM). However, these two possibilities can be discarded because voltages are present on the secondary side through the transformer inside CI-PSU.

As for ③ of 2) components (except those imported from overseas) which could have caused short circuiting on their own singly include 24 ceramic condensors, 7 resisters, and unprotected 43 ICs. It is possible that any one of these could have caused short circuiting mulfunction, or alternatively, short circuiting inside the imported components could be assumed to have caused the mulfunction we have been looking at.

From all these above based on FTA we may summarise the failure causes whose responsibility cannot be ruled out completely as shown in the following (2

(2) Failure causes of short circuiting mulfunction

1) Influence of high energy particles arising from solar flare

a) Deteriolation effects by total dosage

Deteriolation by total dosage is often seen as the cause of solar cell deteriolation by the cumulative effects of high energy particles and appears as an increase in power consumption.

It is without doubt that NOZOMI encountered a very rare and massive groups of high energy particles. However, as of the peak flux on 22 April 2002 plus or minus a few days there was no significant power consumption increase which suggested above mentioned deteriolation (see schematic III-2-3).

In fact, the cumulative dose estimated from the lower portion of schematic III-1-7 suggests that it was similar to NOZOMI's design value (10krad equivalent assuming 1mm Al thickness) was within the tolerance limit. For this reason we may discard, as unlikely, the possibility of the total dosage leading to deteriolation which caused the mulfunction.


cool.gif Failure by a single event upset

For this to be the cause following two conditions must be satisfied at the same time to explain the mulfunction of this time

① Unexpected switching over took place by a single event upset (note 11)


② Devices which could be switched on by above ① had already caused short circuting, or caused short circuiting following it

Of these, one possibility with NOZOMI is the INS-SA which is used only at the time of launch. Since it is used only at launch time components after the relays are all meant for commercial uses.

However, this particular device had been turned off after launch and it is confirmed that it stayed that way until the day when we lost signals on 24 April 2002. The possibility of this particular relay device being induced to be turned ON, as estimated from the solar proton minitor's count number (graph III-1-6), is 1,000 times higher on 22 April compared with the signal loss date of 24 April.

Furthermore, all this cannot explain the mulfunction of this time unless a short cuircuiting had already taken place in the system after the relay by the time the relay was turned ON, or alternatively a short circuiting did take place within a few hours of being turned ON.


- 24 -

(See, 24 above, it is happening again! this should be 23. It has been there all the time until I noticed it now, I think)

(note 11) single event upset (this ref is on page 24)

Bit flipping by passgae of high enery particles through ICs

end of page 23

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Posted by: pandaneko Nov 18 2011, 09:25 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 24

c) Mulfunction by latch-up

About the possibility of ICs latching-up (note 12) by high energy particles those ICs used on board except one of them (59MeV/(mg/cm)) had line (or linear, P) energy investment (this must be wrong and it is most certainly "tolerance" or something starting with T, because abbreviation is, P) (LET) of more than 75MeV/(mg/cm ).

Even if we assume more than 59MeV/(mg/cm ) the possibility of latching-up by galactic cosmic rays is thought to be once in a thousand years or so.

Furthermore, the solar flare of 21 April was such that protons should not have reached the sort of energy which might have caused the latch-ups. Even if we turn our attention to heavier particles such as iron they only appear during the initial stage of the event and it is unthinkable for them to cause failre after a few days of the solar flaring event.

(note 12) : Latch-up

Short circuiting inside ICs

2) Destruction/electromagnetic interferance by discharge

It is possible that discharging may have caused a current flow through the satellite body and onboard instruments/devices may have been affected through latch-ups etc. About this discharging there are a few possibilities as follows.


a) Charging and discharging by high energy particles

Discharging could be caused by accumulation of a large amount of electric charge inside conductive layers which are not earthed. However, in the case of NOZOMI, because of observation requirements an absolute care had been taken regarding charging and discharging issues and as shown per below there are few places for charge accumulation and the possibility is considered to be extremely low.


・All external surfaces of the satellite

These surfaces are earthed to the satellite frame structure with 1MΩ or below and only one exception are a few patches on the rear side of the solar cell panels.


・ Thermal blanckets (MLI)

All layers with areas larger than 100cm (sic, P) are earthed. Also, the surface material is "Black C(or K, P) apton" (carbon coating) and no cracks are possible and for this reason earth lines being cut is unimaginable.


・Inside of the satellite

- 25 - (here again, this should read 24 and when I checked this before translation with the original it was 24... I will no longer be yapping about this as it should not have been any of your concern, P)

All conductors are earthed down to the level of shielding layers for electrical appliances and unearthed circuit ground pattern does not exist as far as the design is concerend. For this reason it is unimaginable for charge accumulation to take place which may lead to discharging.

end of page 24

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Posted by: pandaneko Nov 19 2011, 09:46 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 25

cool.gif Destruction/EM interference by high voltage instruments discharging

In the case of Nozomi all high voltage devices were thoroughly designed as shown per below so that they do not affect the working of other instruments and it is not thinkable that the secondary side of CI-PSU were affected.


① Dust counter (MDC)(±200V)

The high voltage part of the high energy particle counter (EIS)(3kV) is shrouded by the secondary ground of the instrument and even if discharges happen the design is such that no current will directly flow into the satellite structure.


② Ultraviolet imaging system (UVS)(3kV)

The sensor area which receives the high voltage is contained in a vacuum filled glass case. The part exposed to the external area is only the connecting part of the high tension cables and even those are designed so as not to affect the satellite structure.

(3) Estimating the causes of mulfunction

In the discussion concerning (2) above it is true that Nozomi did encounter a very rare magnitude of solar flare which produced groups of high energy partilces. However, there is no data available to verify the relationship between the mulfunction and the the solar flare. Furthermore, the possibility of destruction/EM interference by discharging is thought to be extremely low given the degree of thorough preparation at design stages.

For these reasons the only remaining cause of mulfunction is an accidental component failure. However, here again, the candidate component groups which could lead to single point of failure were rated at quality assurance level as class S equivalent (space use components) and from the viewpoint of failure rate the possibility of failure isthought to be low.

Table III-2-1 shows the accidental failure rates of main class S components.

Those components which may cause mulfunction are those that exist in the secondary side of the circuit and failure candidates and their properties are as follows.


①Ceramic condensors (24 of them)

Even the largest accidental failure rate per one component is something like once in 90,000 years and this rate is regarded as extremely low as the single failure candidate. For your information, in the case of Nozomi, all the ceramic condensors were selected on the basis of anti-deteriolation and anti-high tension.

② Resisters (7 of them)

Here, the largest accidental failure rate is something like once in 20,000 years and furthermore, the possibility of line breakage leading to mulfunction is more likely. Thus, we do not believe that they were the causes of single failure event.

- 25 -

For your information, in the case of Nozomi, all resister were selected on the basis of anti-power deteriolation.

end of page 25

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Posted by: pandaneko Nov 20 2011, 09:22 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 26

③ Unprotected ICs (43 of them)

Probability of accidental failure rate is something like once in 10,000 years and this probability is considered to be extremely low. For your information, it is becoming increasingly difficult with latest ICs to insert protective registers given their large current amplitude and allowable voltage width, leading to a larger number of candidate (suspect, I think. P) ICs.


Also, we can think of, as candidates, the status monitor (LVDT) which is an imported unit for monitoring open/close status of the valve, ultra highly stable resonator (USO), internal short circuting of pressure sensors. With these, we find it difficult to make evaluation for the cause of mulfunction as although they have good track records to have been on board many satellites we simply do not know the circuit inside these black box units.

As you have seen above we have been able to whittle down to a few units which might have caused the mulfunction. However, it is difficult to pin down on specific single units for cause clarification.

end of page 26

P

Posted by: pandaneko Nov 21 2011, 09:35 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 27


Ⅳ.For the future

1.For the future of fuel supply system

(1) Measures to be taken in selecting the valves

From the mulfunction of this time we can point out two major issues relating to the selection of valves for Nozomi. These are the fact that we made a design change to the valve which had an ample track record of going on board in space and also the verification methodology of that valve. We show measures to be taken in relation to these two issues as follows.

1) About design changes

The valve we are talking about as developping a mulfunction is LV2. Originally, this valve made by a certain US manufacturer with ample flight records was changed at the request of the then Institute of Space and Astronautical Sciences (ISAS) to include a status monitor (LVDT) for monitoring of valve opening and closing.

This LVDT was added to the existing valve to ensure reliable operation of LV2. It meant that the valve with enough track records but lacking the monitoring function was changed to include LVDT as a post desgin alteration.

As for this change of design, since it was made by a specialist US manufacturer based on existing design with track records we thought, at the time of decision making, that the risk involved was small enough, but we now think that our study at that time was not satisfactory.

At this time, given the structure of Nozomi, we had to introduce a design alteration to LV2, but we think that inherent risks involved in desgin altered componets must be treated adequately.


2) About the verification methodology

Most of space use valves are imported from overseas and in some cases detailed structural indormation and availability of technical information is limited. It is vital to establish high reliability with these products. With Nozomi we did conduct LV2 verification and evaluation as shown below, but we now think that it was not enough.

With Nozomi verification tests were conducted as shown on tables II-2-2 and II-2-3. We also requested the US manufacturer for similar verification and in Japan we conducted an independent study on the NTO vapour arising from the oxidiser. We conducted an even harsher test of sealing NTO liquid inside a valve for keeping and for action tests, thereby verifying the durability of the valve against NTO environment and confirmation of its health.

This particular test was conducted so as to verify that LV2 had durability against NTO and lasted only for two months equivalent length. In that sense it was, strictly speaking, not an accelerating test approapriate for Nozomi's operational lifetime (one year had been assumed)


- 27 -

The number of valving actions during the accerleratin test is important from the viewpoint of verifying the influence of that number affecting the condition of the sliding part of the valve. In our case this time it was less than 10 cycles of opening and closing that were tested in the oxidiser environment and we cannot deny the possibility of it being inadequate for taking into consideration the possibility of fletching wears etc.

From all these reasons mentioned as above we should have paid a lot more attention to the issue of conditions in which verification is sought. Valves in particular have wide areas of concern relating to electricals, materials, fluid dynamics etc and we should be closely working with specialists in these areas both inside and outside our organisation in order to check if proposed verification methods are adequate for our purpose.

With imported valves we may think of, as a means to further improve on the adequacy evaluation technique, an early detection of valve deteriolation from the changes appearing in the current wave profile imprinted (or imposed?, P) on the valve. Clearly, we should be spending a lot more on strengthening our verification stance.


end of page 27

P

Posted by: pandaneko Nov 22 2011, 09:12 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 28


(2) Measures taken in our satellite operation

Given Nozomi's launch window the timing of OME firing for transfer orbital insertion (TMI) had to be within the invisible time zone in our orbit plan design. We outline the measures taken in operating this satellite as follows.

In order to combat invisible operation during TMI we thought of requesting the support of NASA's Deep Space Network (DSN) or ESA so that they may allow the use of of their ground stations. However, our final decision was that we will not be requesting their support for the following reasons.


・Nozomi was equippred with automatic OME firing function.

・ This automatic OME firing function was also going to be used in Mars orbital insertion and a thorough ground verification had been made.

・It had been planned so that an orbital firing test of this automatic function was going to be made during visible operational period (in fact, this automatic OME firing was tested about 4 months before TMI during ΔV5).

・ Nozomi's TMI timing coincided with the period in which Nozomi was also invisible to DSN and ESA ground stations.

However, we cannot deny the fact that had we been able to send an immdeiate response command to the event that happend in real time monitoring in visible operation through telemetry we may have been able to carry out the originally planned task. This does suggest that securing operational visibility is very important. One such measure that can be taken in this respect is to request the support of overseas ground stations. We can think of a few things as follows for achieving this.


・ Make preparations through international cooperation so that quick response commands can be sent out by DSN and ESA ground stations.


・We establish our own overseas ground stations (for example, one such station in South America)

In the case of 20th scientific satellite (Hayabusa) launched in 2003, in this regard, we did request such support from DSN for emergency measures.


- 28 -

However, we must point out that even in the case of visible operation we still have this issue of time lag in deep space operation and that for this reason we will still have to rely on autonomous operation despite the risks inherent in this kind of satellite operation.

end of page 28

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Posted by: pandaneko Nov 23 2011, 09:29 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 29


2.About the measures to be taken in future with comms. and thermal control systems

With the mulfunction in comms. and thermal control systems it is difficult to pinpoint single causes of the mulfunction given that as mentioned before it is difficult to be specific about the causality with solar flares and also that thorough measures had been taken with respect to the possibility of discharging in the design of Nozomi.

For this reason the remaining possible mulfunction candidate is the accidental failure of components and measures to be taken in this regard can be as follows. For your information other measures to be taken with respect to the cause candidates which are extremely unlikely to be true given the thorough preparations that had gone into Nozomi's flight are seperately listed on the table IV-2-1.

(1) Responding by seperating out failures

With these interplanetory missions such as one attempted by Nozomi we can gain precious engineering and physical knowledge from the mere fact that the mission existed at all in outer space. For this very reason we should endevour to make sure that we produce a design which will allow continuation of the mission even if some of the on-board devices develop mulfunctions.

With this in mind we then must reduce the number of mulfunction possibilities and even in the event of mulfunction our design should be able to localise its effects and prevent its ripple effect eating into the more superior systems by placing more emphasis on seperating out failure causes.

In this regard in the case of Nozomi we must admit that not enough care had been taken to prevent an initial mulfunction of the component(s) which occurred on the secondary side of CI-PSU system from spreading into the more superior CI-PSU. For your information the method and characteristics of failure separation and some examples are listed on the tables IV-2-2 and IV-2-3.

(2) Development of components which will not cause latch-ups

With latest components it is becoming increasingly difficult to insert protective registers since their current amplitudes are large and allowable voltage bands are narrow. Also, even with those components which have small possibility of latching-up we are still talking about probability of mulfunction and there is no way we can say that they will not fail.



For this reason developments are underway for semiconductor devices such as "silicon on insulator" (SOI).

- 29 -

We are aware that these devices are being developped for consumer uses. However, we should also try and carry out further research so that these may be used as space flight components.

end of page 29

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Posted by: pandaneko Nov 24 2011, 09:39 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 30

3.Reflecting into the design philosophy of scientific satellites

About the two accidents that befell on Nozomi and the causes of mulfunction and measures to be taken for future we have been talking about fuel supply and comms./thermal control systems respectively. Scientific satellites come in different shapes and internal structures depending on mission requirements.

It is therefore important that we should reflect the measures we have discussed as a result of Nozomi's failure and particularly those ones that are commonly applicable to future scientific satellites into their design philosophy and development.

What follows are those items which we think should be incorporated into the design philosophy of future scientific satellites.


(1) Alterations to exisitng design

Whenever we try to make changes in the desing of the components to go on board we should remind ourselves that this will carry the same degree of risks as in designing them from scratch even if these changes are to be made on those that have enough track records.

For this reason it should become our design philosophy to examine the risks involved in changes made to proven designs and if we had to we should be taking every possible caution in determining the neccesity of desin alteration and possible repurcussions/verification methods etc. by calling for specialist advice from a wide range of desciplines.


(2) Ground tests

Naturally, with components and instruments to go on board any scientific satellites it is imperative that they are highly reliable with enough proven records. However, this is not always easy as mission contents and development times are all different and we may not always be able to fulfill these requirements.

Therefore, it is important that pre-flight ground tests should amply verify and evaluate the reliability/functions/capacities of those components going on board. Furthere more, we should make sure that an exccessive loading is not placed on the pieces to be tested and that the test contents are sufficiently approapriate and effective (including the influence of operational environment) for the purpose of verification leading to reliable data by inviting professional advice from specialists both within and outside our organization.

In the event of ground tests not leading to convincing reliability we should take a renewed look into the desing steps of to-be-on board components and insturments with a view to completely returning to design board.

end of page 30

P

Posted by: pandaneko Nov 25 2011, 09:41 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 31


(3) Dealing with imports

There are cases where we have to procure imported items for space use with scientific satellites such as their components and devices because they are not produced in this country. With these imported items even if information on verification tests and flight records against our specs can be obtained from manufacturers it may not always mean that detailed internal structural information is available.

In these cases of limited availability of information on internal structure of devices and their electrical interfaces we must ensure that not only verification tests from user's point of view are carried out but also we must give utmost priority to the issue of seperating out failure causes.

Furthermore, we must, in the event of import troubles, make sure to cooperate with the manufacturers to clarify the status with a view to coming up with approapriate measures for rectifying the situation not just by oursleves but also with the cooperation of all organisations involved.

(4 ) Seperating out failure causes

Space systems cannot exclude the possibility of mulfunctions completely. Nor can we expect to be able to carry out repairt works in orbit. For these reasons we mus ensure that partial mulfunction by onboard devices will not lead to a total mission loss. We lay out points to note in trying to seperate out failure causes as follows.


① About the degree of seriousness of mulfunction in hand we must be able to evaluate the seriousness of possible repercussions to the system as a whole by making use of evaluation methods such as Failure Mode Effects Analysis (?, P)(FMEA) and Failure Mode influence fatality analysis (FMECA) so that the trouble in hand will not spread to other important systems by giving preferential priority to the failure cause seperation.

② Based on the priority judged by ① above we must make selective (given seriousness, repercussions and importance of the troubles) judgement on the possibility of mulfunction seperation and containment such as adoption of redundancy, seperation of power sources, building in of protective resisters etc.

③ With those items whose functional loss will not lead to serious faitality or those which are used only at the time of launch etc., that is to say, those items whose mulfunctions will not spread into secondary fatalities and therefore do not need our utmost attention we must select as much as possible the least troublesome failure cause seperation measures (such as the use of protective registers and installation of switches etc.).

(5) Trouble shooting by software

In the case of Nozomi our operation continued even after the accident in 2002. In fact, our continued operation of Nozomi lasted for 5 years from the launch in July 1999 to December 2003. This was made possible by several factors such as an improvement made on autonomous function and re-writing of data handling unit (DHU) software etc.

- 31 -

Being able to re-write the software after launch from the ground is an extremely effective measure to deal with various troublesome situations as we can pliably deal with different events by making the on-board devices carry out different functions. Naturally, similar capability has been adopted for the scientfic satellites which are in the pipeline and it is thought that changes in hardware functions by software re-writing will be popular from now on.

On the other hand we should note that use of unverified software is very dangerous. Therefore, it is imperative that we conduct sufficient ground tests with each of the software functions in order to establish reliability. Also, in the event that on-board software re-writing is deemed paramout we must first thoroughly check the safety of re-writing with a flight model and its electrically equivalent functional devices. Actual re-writing will have to be made based on the result of these ground tests.

end of page 31

P

Posted by: pandaneko Nov 26 2011, 09:42 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 32

(6) Measures for deep space exploratory mission


In addition to above measures we may add a few other measures as follows, which may turn out to be effective with future Nozomi like deep space missions.


・Development of low bit rate comunication function for emergency cases

・Development of a system which is further improved on the system with new functions as follows used for the 20th scientific satellite (Hayabusa) for verification in deep space

Hayabusa was launched in 2003 as a deep space mission after Nozomi (18th scientific satellite). Hayabusa has following functions in addition to those available to Nozomi.


・Report packeting function

Function whereby results of autonomous actions are sent out each time by dedicated packets. If labour saving is wanted in operation then operation can be achieved only by report packeting.


・Choice of sampling rate at reproducing HK telemetry

Function whereby coarse transmission rate is used for coarse data scanning to be followed up later with only the required portion of data by higher sampling rate.

・System timer function

Function whereby commands are executed after a specified amount of time lapse, timing function for general purposes.

The measures intended for future as described by this current report as a result of Nozomi's failure are issues specific to all scientific satellites designed for deep space mission.

- 32 -

However, these are also issues commonly relating to space use devices and system development. Therefore, it is the wish of our organisation that these measures will be fully utilised for future space activities with increased reliability.

end of page 32

(I have not looked at the portion immediately after this, but I suspect that this might be the end of this report proper, only to be followed by supporting materials (appendices), which I will also translate, P)

Posted by: pandaneko Nov 27 2011, 09:23 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 34 (all pages before page 34 except those already translated are somehow missing from this report, P)

fig. 1-1-1 Nozomi final shape upon extending everything

page 35

Table Ⅰ-1-1 List of instruments on board (1/2)

Scientific observations achieved during cruising period

Instrument name:: Result
[collaborators ]

MIC:Mars imaging camera:: First view of the other side of the Moon by a Japanese camera etc.
[Kobe Univ,ISAS/JAXA etc. and CNRS]

UVS:Ultra violet imaging camera:: observation of interstellar winds outside solar system etc.
[Tohoku Univ, National Inst. of Polar Research etc. ]

XUV:Extreme ultraviolet imaging camera:: 1st imaging of earth plasma sphere etc.
[Nagoya Univ, Boston Univ, etc.]

MDC:Dusts conter:: detection of interstellar dusts etc.
[Munich Inst. of Tech, Tokyo Univ, ISAS/JAXA・LFM・MPIK・STMS, ESA etc.]

EIS:High energy particle counter:: observation of solar flares etc.
[Tamagawa Univ, ISAS/JAXA, MPIA etc.]

ESA:Electron energy analyser:: observation of lunar wake (unsure, P) etc.
[Kyoto Univ, ISAS/JAXA etc.]

ISA:Ion energy analyser:: observation of interstellar winds etc.
[ISAS/JAXA etc.]

IMI:Ion mass analyser:: long term monitoring of solar winds etc.
[IRF・Rikkyo Univ, ISAS/JAXA, etc.]

MGF:Magnetic fields measuerer:: long term monitoring of soalr winds etc.
[ISAS/JAXA・Nagoya Univ, NASA/GSFC etc.]

RS:scientific observation of EM waves:: observation of solar corona structure etc.
[ISAS/JAXA]

end of page 35

P

Posted by: pandaneko Nov 28 2011, 08:44 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 36


Table Ⅰ-1-1 List of Nozomi insturments (2/2)

Instrument:: result expected to have been obtained after insertion into Mars circular orbit
[participants]

PWS: Plasma oscillation sounder:: radar probing of ionosphere etc.
[Tohoku Univ. ISAS/JAXA etc.]

LFA:Low frequency wave observer:: observation of perturbation in ionosphere etc.
[Kyoto Univ RASC, Toyama Prefectural Univ., ISAS/JAXA etc.]

PET: Electron probe temperature:: First imaging of plasma regio0n of Earth etc.
[ISAS/JAXA, Michigan Univ, MPIA, a Korean inst. etc.]

NMS: Neutral particle mass analyser:: detection of interstellar dusts etc.
[NASA/GSFC, Michigan Univ, Arizona Univ, Univ. of Hawaii,ISAS/JAXA etc]

TPA: Thermal plasma analyser:: Observation of constituents of ionosphere etc.
[Univ. of Calgary, ISAS/JAXA・NRC・CSA, Univ. of Victoria, Univ. of Western Pntario, Univ. of Alberta, etc.]

end of page 36

P

Posted by: pandaneko Nov 29 2011, 09:05 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

I had a quick look at the rest of this report and am satisfied that it does relate directly to failure causes. Therefore, I will continue with my translation, but there are a very few pages (I suspect 2 or 3such pages) which are irrelevant. One such is as follows as page 37. I am translating this page for completeness sake.

page 37

Table Ⅰ―1-2 List of engineering objectives achieved with Nozomi

Engineering objective:: Outline (as follows)

mission analysis:: coming up with an optimum mission scenario by trading-off, given limited resources and time, all those engineering options available

orbit planning:: ability to design orbits peculiar to planetary mission such as swingby techniques with the Moon and the Earth

high precision orbit determination:: by waves from the ground obtain velocity and line of vision distance data to be fed into precision dynamical modelling in order to determine the deep space probe's orbit with high accuracy


autonomous operation:: AI technique for letting the onboard computer make judgements

ultra long distance communication:: communication equipment and operational knowhow for the long distance (max. 4 times 10 to the power of 8 km) communication

weight reduction of the onboard instruments:: reducing the weight of all onboard devices including propulsion, solar batteries, antenna, batteries, electronics given that deep space probing requires considerably more energy at launch

ground support software:: ground software with AI capability given that safe operation of the deep space probe requires operation under complex constraints including a long term cruising phase


end of page 37

P

Posted by: pandaneko Nov 30 2011, 09:04 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 38

fig I-1-2

instrument location on board

page 39

Table Ⅰ―2-1 Targets which became possible as a result of M-V launcher

Research targets

1) internal structure of planets

Observation of earthqua: Lunar penetrator
→Lunar-A (1997→2004) (development of penetrator)

2)pristine astonomical bodies

sample return from near earth asteroid
→MUSES-C「Hayabusa」(launch May 2003)

3) planetory environemtn

Venus/Mars:PLANET-B(「Nozomi」1996→1998)(M-V development)

Table Ⅰ―2-2 other Mars probing missions in plan at the time of Nozomi concept

Launch year : satellite name: planned by

1988: Phobos1 & Phobos2: former Soviet Union
1992: Mars Observer: US
1996: Mars96: former Soviet Union

Table Ⅰ―2-3 Weight reduction and some examples

target: result

adoption of nickel/hydrogen batteries: 2kg

CFRP treatment of GHe tank: 6kg

development of high gain light weight antenna: 4kg

adoption of new connectors for wiring within common use devices: 3kg

Weight reduction of S band receiver: 1.5kg

adoption of dispersed power source (comparison with centralised system): 3.6kg

end of page 39

P

Posted by: pandaneko Dec 2 2011, 09:26 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 40

fig. I-3-1

New orbital plan for Nozomi

(here, I will have to explain, rather than translate as follows)

red: Mars
green: Earth
purple: Nozomi

(on this Earth-Mars system main character strings clockwise are)

1. 1st earth swingby: Dec 2002
2. leaving Earth gravitational field: Mars Dec 1998
3. insertion into Mars orbit: end 2003 to early 2004
4. 2nd earth swingby: June 2003

(on this page there is another Earth-Mars system in a square. The Monn is in yellows and Mars is depicted in red, with a short caption near Mars which says "into Mars orbit: Oct 1999)

end of page 40

page 41

fig I-3-2 Temp changes at temp measurement point(s?) by 1 bit communication

(Here, I have no idea as to what WANT is, but anyway)

Vertical axis is WANT temp and horizontal is the dates, from 23 July to 1 October. On the upper lef a box contains 5 character strings from top to bottom. The last one at bottom says "fitting of WANT-1".

Similarly, there are 5 character strings all pointing to the slanted line on the graph and the last one at bottom of this group of 5 character strings says "fitting of WANT-1"

The cpation of the arrow pointing vertically upward to the slanted line says "melting point under hydrazine tank pressure (2.2 deg C)"

There is another character string qualifying the same slanted line and this says "temp. increase rate per day of 0.32 deg C"

end of page 41

P


Posted by: pandaneko Dec 3 2011, 10:00 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 42

(main feature of this page is a figure and a table)

Fig. II-1-1 Nozomi propulsion system outline

Most of this figure is in English. There are 5 oblong squares in dark blue. 3 of them to the left and 2 of them to the right.

Left ones from top to bottom are:

Pusher gas tank He
Fuel tank Hydrazine
Auxilliary engine RCS (mono propellant)

Right side one from top to bottm are:

NTO tank
Main engine (dual propellant) and the caption for this says "To be used for insertion into Mars transfer orbit"

In addition, there are 5 squares in light blue: They indicate the status of the valves. In this diagram all of these 5 squares carry "OPEN".

In further addition there are one red oblong square and the characters in there say: LV2: CLOSE->OPEN->CLOSE and one pale blue oblong square and the characters in there say: LV5,6: CLOSE->OPEN->CLOSE

There are two circles in this figure and one near the top and the caption for that says "Valve which developped mulfunction" and the other one near the bottom is OME.

There is a note also in the figure and it says "Valve status is all during TMI"

The qualifiers in the figure are as follows.

HLV: high pressure gas system latching valve
LV1-2, LVm: low pressure gas system latching valve
LV3-6: liquid system latching valve
RG: regulator
CV1-2: check valve
F1-3: filter
P1-4: pressure sensor

FDV1-5: inlet/outlet valve
TP1-5: test port
A&T1-4, R1&2: RCS thruster
OME: OME
FTNK-A&B: hydrazine tank
OTNK-A&B: NTO tank
GTNK: He tank

Table II-1-1 Main specs for propulsion system

Here, I will translate column by column, from left to right and from top to bottom. Sometimes, I will add row numbers so that we know where exactly we are down the columns.

Leftmost column and from top to bottom:

pressure
thruster specific impulse
thruster specific impulse
torque (9 and 10 are row numbers)
gas container or gas reservoir?
fuel tank (x2)
oxidiser tank (x2)
onborad propellant amount (20 and 21 Ditto)
effective propellant amount
propulsion system DRY mass
propulsion system WET mass

Now, second column from top to bottom:

initial pressure in the primary pressure system
initial pressure in the secondary pressure system
axial (x4)
radial (x2)
tangential (x4)
OME (x1)
RCS
OME

3rd column is as follows:

precession
spin
inner volume
MDP
destruction safety rate
inner volume
MDP
destruction safety rate
fuel (hydrazine)
oxidiser (NTO)
for RCS
for OME

the next column is nominal specs and the contents are from top to bottom (and I omit those in English):

2.3N per base
2.3N per base
2.3N per base

27.8 litter

98 litter per tank

40 litter per tank

and the last column is meant for notes and the contents are:

(=24.5 MPa)
(=1.37 MPa)

at time of pulse is given
lower or lowest limit of somekind of difference
R=1m at time of two in action
R=1m at time of two in action
CFRP/titanium alloy sphere
tatanium alloy tear drop shaped (=2.01 MPa)
titanium alloy tear drop shaped

end of page 42

P


Posted by: pandaneko Dec 4 2011, 09:06 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 42

fig. II-1-2 Status at the time of failure in December 1999 (time is UTC)

(Here, most of the time line is in English. I simply suppllement those with captions in Japanese)

07:17 Start of attitude change (sun angle 60 degrees)

07:33 attitude control completed (sun angle 120 degrees)

07:41 SPIN-Up (->25 RPM) time taken is 1 minute

08:06:20 to 08:13:04 OME fired

08:32 SPIN-Down (->10 RPM) time taken is 1 minute

08:40 Start of attitude change (sun angle 120 degrees)

09:00 Attitude control completed (sun angle 43 degrees)

(character string inside this large box says):

all monitored values and status were normal except that the monitored value of NTO upstream pressure started declining as the firing started. (confirmed by reproduced TLM)

(the 1st red arrow pointing at 12:00 says): News flash from JPL that there was an insufficiency (shortfall of delta V) of about 100 m/s against the planned value of 423.22 m/s

(2nd red arrow just past 14:00 says): similar insufficiency confirmed by onboard TLM integration

end of page 42

P

Posted by: pandaneko Dec 5 2011, 09:51 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 44

fig. II-1-3 Telemetry data during visible period after insertion into Mars transfer orbit (TMI)

(here, the only thing that needs translation is the caption inside a Mexican hat like area and it says):

oxidiser tank pressure P4 is low

end of page 44

page 45

fig. II-1-4 Nozomi status at time of LV2 open command (part 1)

(here, there are 9 squares in yellow and they are, from top to bottom):

P1: pressure of gas storage
P2: regulator exit pressure
P3: fuel tank pressure
P4: oxidiser tank pressure

injector temp.
OME firing duration (or time?)
delta V
LV2 status
LV2 open

(There are 3 blocks in pink and they are):

(referring to P2): transient decrease in regulator pressure due to rapid supply of He gas to oxidiser tank which was judged to be lower than normal

(referring to P4): pressure rise as LV2 is opened -> He gas is being supplied

(last small square): pressure drop is judged to be due to imperfect opening of LV2

(there are 2 more small squares in pale blue and they are):

(top square): Open
(bottom square): Close

end of page 45

P

Posted by: pandaneko Dec 6 2011, 12:09 PM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 46

fig. II-1-5 Nozomi status at time of LV2 open command (part 2)

(caption on the left says): Shock due to LV2 opening

(caption on the right says): Vibration due to He gas flow

end of page 46

page 47

fig. II-1-6 Status of OME firing at time of insertion into Mars transfer orbit (TMI)

(here, there are 11 pale yellows areas with captions and I will go from top to bottom, then bottm to right, in this order)

P1: pressure of storage tank
P2: pressure at regulator exit
P3: fuel tank pressure
P4: oxidiser tank pressure

injector temp.
OME firing time (or duration/)
delta V
status of LV2
LV2 open (this is the bottom and I will move right from here)

OME firng start
OME firing end/LV2 close

(now lines in red)

(dotted lines in red next to P4 says): originally planned regulator level
(red solid line next to delta V says): target delta V (423.33m/s)

(there are cations in 3 pink areas. they are, from top to bottom)

Not regulated like P2, P3 -> insufficient supply of He gas

insufficient amount of delta V

status changes in response to OPEN/CLOSE command

(what remains are 2 pale blue areas and they are from top to bottom)

OPEN (top)
CLOSE (bottom)

end of page 47

P

Posted by: pandaneko Dec 7 2011, 08:42 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 48

fig. II-1-7 Changes in pressure and acceleration at time of TMI

(here, left vertical axis is pressure and the right handside vertical axis is average acceleration. The horizontal axis is OME firing time (sec))

(on the graph itself, the brown curve is acceleration and inside the square the brown dot is also acceleration)

end of page 48

page 49

fig. II-1-8 Comparison of regulated pressure and propulsion

(here, the bottom line inside the square is predicted propulsion)

end of page 49

page 50

fig. II-1-9 Fuel system pressure trend

(here, inside the square we have):

P2: regulator regulated pressure
P3: fuel tank pressure
P4: oxidiser tank pressure
Pc: 500N thruster burn pressure

end of page 50

page 51

fig. II-1-10 Oxidiser system pressure trend

(captions inside the square are exactly the same as on page 50

end of page 51

P


Posted by: pandaneko Dec 8 2011, 09:41 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 52

Table II-2-1 Risks considered at time of LV2 selection

(here, I consider this table essentially to consist of 6 columns and 6 rows for ease of translation and that means tacit understanding that some of the table elements have more than one rows or columns)

(top left corner contains a caption): "Options available at time of selection"
(top right corner contains a caption): "Notes"

(top row with column numbers 3,4,5 contanis a caption): "Risks envisaged"

(hereafter I will use regular R and C numbers)

R2C3: mixture of hydrazine and NTO
R2C4: LV2 cannot be opened (valve reliability issue)
R2C5: LV2 open status cannot be monitored

R3C2: Extent of risk influence
R3C3: catastrophic
R3C4: serious
R3C5: local or localised

R4,5C1: LV2 is used
R6C1: LV2 is not used

(against these headers translated as above there are symbolic entries with either triangle, double circle, single circle and I will qualify these symbols after translating the rest of this table. Just to make sure we are using the same esignation there are triangles at R5C5 and R6C3)

R6C6: Valve is not used at all
R5C6: Valve with track records
R4C6: Valve modified to our spec

R4C2: Instruction for open/close is given
R5C2: Instruction for open/close is not given

(symbols are as follows)

◎: unthinkable from the viewpoint of principles
○: small risk (acceptable to the mission)
△: medium risk ( either acceptable to the mission or detailed assessment required)
×: too risky (unacceptable to the mission)

※Result of risk assessment

For the following reasons it was decided that we will carry LV2 and also add LVDT to go with LV2

・Vapour mixture of hydrazine and NTO

When vapour mixture takes place it will mean a very serious risk to the mission. If LV2 is used it means dual safety precaution given the role of CV2 and the risk is deemed small. However, safety precaution with CV2 only is medium in risk taking.


・LV2 cannot be opened

If LV2 is found not to open prior to TMI it will mean a very serious risk to the mission. However, by carrying out a prior checkup of LV2 the possibility of valve unopening can be reduced to a minimum, hence small risk.


・LV2 open/close status cannnot be monitored

Being unable to monitor LV2 status is not that serious and is localised. However, if we consider the burden on operators and human errors due to this burden we thought that having a monitor will reduce the risk to minimum. No monitor, then risk is deemed medimum.

end of page 52

P

Posted by: pandaneko Dec 9 2011, 10:08 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 53

fig. II-2-1 Schematic of LV2 gas system latching valve

(there are 4 brown squares and these are colis)

(light blue areas are ferrite stainless steel)

(grey area in the middle is Inner piece or Inner member (presumably movable component?, P))

(to the left of above is the plug)

(incoming yellow arrow says: from He tank)

(outgoing arrow says: to oxidiser tank)

(what is seen on the extreme right is the LVDT)

Note: There is a guide with LV2 so that the inner piece is accurately centred.

end of page 53

page 54

table II-2-2 Ground test history of LV2 valve

(this is a table and I consider it to be made of 4 major columns which subdivide)


C1R1: inspection (or test)/pressurised (or loaded?, or even subjected to test?,P) items environment
C1R2: capability confirmation test
C1R3: vibration
C1R4: mechanical shock
C1R5: thermal environment
C1R6: life cycle
C1R7: oxidiser environment 1
C1R8: oxidiser environment 2

C2R1: design quality confirmation test

C21R2 (1st subcolumn of C2R2 is meant): items carried out by valve manufacturer (QT)
C22R2 (2nd subcolumn of C2R2 is meant): items carried out domestically

C2R3C1 (C1 is a subcolumn within C2, counted from left to right): function
C2R3C2: mechanical environment
C2R3C3: thermal
C2R3C4: life (or durability)
C2R3C5: immersion test

C3R1: flight model manufacturing approapriateness confirmation test

C31R2 (1st subcolumn in the main column C3 is meant): AT
C32R2: subsystem (domestic)
C33R2: at system level (domestic)

C3R3C1: items carried out (by valve manufacturer)
C3R3C2: module test or modular test
C3R3C3: subsystem test
C3R3C4: test immediately after incorporation into the system
C3R3C5: thermal test
C3R3C6: mechanical environment
C3R3C7: thermal vacuum
C3R3C8: test immediately upon arrival at launch site

C4R1: Note

C4R4: double circle is a detailed test and a single circle is a simplified test

C4R9: valve on its own (exposed 16 hours to vapour)

C4R10: valve on its own (left in running NTO for 5 hours)

end of page 54

P




Posted by: pandaneko Dec 11 2011, 09:57 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf



above for ease of reference

page 55

Table II-2-3 Number of cycles of valve open/close action

(this table, I consider it to be consisting of 6 rows)

(top row headers are from left to right)

category: status: number of cycles, in this order

C1R2: exposure to oxidiser vapour
C1R3: immersion in oxidiser liquid

(status members from top to bottom are):

(1): before exposure
(2): immediately after exposure (0.3 MPa)
(3): 16.5 hours after exposure
(4): vapour pressure reduced to 1 atmosphere
(5): after gas is purged

(6) during immersion in running liquid (differential pressure of 0.35 MPa and 5 hours continuous)
(7): after liquid is purged
(8): after cleaning and drying

end of page 55

P

Posted by: pandaneko Dec 12 2011, 09:51 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

Please note that in what follows and in all previous translations I am always translating non alphanumeric entries only.

page 56

Table II-2-4 LV2 action history (action refers to opening and closing of the valve, P)

(before translating elements of this table I will first translate what are seen below the table. They are):

Note: Circle: valve opening/closing by autonomous commands (note 1 (actually, I cannot find this Note a anywhere on this page, P))

Square: valve is opened/closed by a command sent manually in real time

*: valve mulfunctioning during TMI was the 42nd (6th after launch) after delivery by manufacturer and the valve function had been all normal before it

*: automated command function relating to OME firing had been confirmed by ground tests. it was also verified during delta V5 in orbit.

(now, table itself and I consider this table to be consisting of 5 majot columns and 4 major rows with subdivisions)

(first, headers in the leftmost column)

C1R1: Action timing

C1R2: ground tests

C1R3: launch

C1R4: after launch

(next, headers in the top row, from left to right)

C2R1: Number of actions

C2R1 divides into 2 subcolumns and the header entry in the left subcolumn is "close->open" and the header in the right subcolumn is "open->close"

C3R1: Operation status

Here again, this divides into 2 subcolumns. Left subcolumn says "Visibility" and the right subcolumn says "Automation".

C4R1: Judgement

C5R1: Notes

(These are the headers and before translating non alphanumeric entries I will spell out some of the dates entries below. Dates in Japanese are reveresd in order. They are YEAR.MONTH.DAY, in this order, and all in numbers. For example):

97.10.21-22 : 21 to 22 October (10th month), 1997
98.2.27-3.4: 27 February (2nd month) to 4 March (3rd month) 1998
98.12.10: 10 December (12th month) 1998

(now, translations)

C3R4 divides into 5 subrows and entries in the Visibility subcolumn from top to bottom are:

Visible
Visible
Visible
invisible (orange colour highlighted)
visible

Likewise Automation subcolumn entries from top to bottom are:

square
circle
square
circle (orange colour highlighted)
square

Entries in the judgement column (major column) C4 are all "normal" except the 2nd subrow from bottom which is "abnormal" and is orange colour highlighted.

There are 16 entries in succession in C5 from top to bottom minus one. They are:

R2: delivery inspection, domestic

R3: confirmation test after pipe welding

R4: air-tightness test 1, whole propulsion system

R5: air-tightness test 2, whole propulsion system

R6: function confirmation test

R7: overall test, propulsive function

R8: overall test, preperation for environment test

R9: overall test, environment test

R10: overall test, functional air-tightness confirmation test

R11: flight operation, air-tightness test

R12: flight operation, liquid injection and primary pressurising

R13: (launch)

R14: Delta V 1

R15: Delta V 5

R16: Delta V 8

R17: Delta V 9 (TMI) and this is orange colour highlighted.

end of page 56

P








Posted by: pandaneko Dec 13 2011, 10:08 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 57

Table II-2-5 FTA for LV2 mulfunction

First of all, notations belows this table.

Cross: not possible
Triangle: small possibility
Single circle: medium possibility
Double circle: large possibility

Top row headers go like:

C1R1: suspected reason
C2R1: judgement
C3R1: reason for judgement
C4R1: operational judgement

Since C1 has subcolumns I will have to de descriptive in some cases.

C1R2: mulfunction with the monitoring device

C1 leftmost subcolumn R3 to R10: mulfunction in device area (best I can translate, I am afraid..., P)

C1 righthand subcolumn R3: mulfunction with the inner piece

C1 righthand subcolumn's left subcolumn R4 to R10: mulfunction in valving action

C1 righthand subcolumn's right subcolumn's rows (and there are many and I will hereafter use R numbers only, P)

above's R4: expansion due to incompatible plug materials

above's R5: bad sliding of the plug

above's R6: plug glitching into valve opening area

above's R7: plug misallignment

above's R8: glitching of (or by) foreign material

above's R9: clearance change at sliding setion due to valve temp. change

above's R10: temporary solidification due to crystal formation (such as nitric ammonia)

(hereafter entries become regular, P)

C3R2: monitor is healthy because open/close sensor indicated that the rod for sensor moved in the same direction as the inner piece in response to the open/close command.

C3R3: inner piece movement is considered to be normal because there was a stroke large enough to change the open/close status monitor and also latching had been secured.

C3R4: mulfunction due to expansion is not possible because of the metal jacket at the sealing section and the jacket itself is resistant to NTO.

C3R5: it is thought that because the valve and the plug are independent and are activated by a differential pressure the valve body surface got roughed up by fletching wear and led to corrosion in NTO environment.

C3R6: it is thought that the valve was slightly opened during TMI. However, in this mulfunction mode the slight opening of the valve is difficult to take place.

C3R7: this must be due to bad manufacturing, but the ground tests did not give any indication.

C3R8: this possibility is low because we used a finer filter than the minimum diametrical clearance.

C3R9: the valve had functioned properly in similar environment in flight.

C3R10: propellant was charged (or injected) after dryness confirmation. Also, this phenomenon should have shown up within a few days.

(now the last column, P)

C4R5: we will leave the valve LV2 in open state because we think that slidability will worsen as time goes by.

C4R6: we will leave the valve LV2 in open state because closing it may lead to the same mulfunction with a high possibility.

C4R7: we will leave the valve LV2 in open state because closing it may lead to the same mulfunction.

C4R8: repetition of mulfunction is thought to be low in possibility because it was accidental and also the foreign material must by now have been carried downstream.

C4R10: we will leave LV2 open as closing it may lead to repetition.

(outside the table there are 5 character strings giving the degree of suspicion as the candidate for causing mulfunction. These sit side by side to Rows 5, 6, 7, 8, and 10 and carry a numerical value of 1 to 5 respectively.)

end of page 57

P


Posted by: pandaneko Dec 14 2011, 09:15 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 58

Table II-2-6 History of LV2 use

(this is a simple table and I just translate the contents in the easiest way as follows. Number of days is just approx.)

Valve remained closed for :

15 days before use as LV2 CLOSE before launch (delta V1) (why delta V at all before launch beats me, P)
42 days before use during delta V1 to delta V5
80 days before use during delta V5 to delta V8
40 days before use during delat V8 to delta V9 (TMI)

end of page 58

page 59

Fig. III-1-1 Nozomi power system schematic

With this schematic I will have to be very descriptive. It all starts from the leftmost square, which is the solar battery.

To the right immediately, and effectively it is a column containing mostly power units, from P1 to P15, say. I hope you can see numbers in this column and I hope they are numerics coded with a single digit. If not you may be looking at a mess.


However, between P2 and P3 there are two more squares. One is "Beacon mode" and the other below it is "Telemetry mode". Actually, there is another square further down between P4 and P5 and that says "Attitude control system and other instruments for observation".

Now, going back to P1 power is sent down to a switch called "Temp. control circuit" which controls the "Main prop. system heater" at the extreme up and right on the schematic.

There is another switch immdeiately below a long horizontal oblong square. This oblong square says "Telemetry Command Interface (TCI)". This second switch is meant to swtich between "Beacon mode" and "Telemetry mode".

There is another square below this switch which says "Transmitter 1" (and I do not find any other transmitters on the schematic, P) and this transmitter is connected to P3 and the switcher above.

Transmitter is also connected to the receiver below it. Both transmitter and receivcer are connected to the antenna on the right (extreme right) and the receiver is receiving power from P4.

The longish square at the bottom says "Data Handling Unit (DTU)" and it has a two way power connection with the telemetry command interface. DTU also connects to the command decoder which sits between the receiver and DHU.

In addition, trhere is another strange square floating below temp. control circuit and the telemetry command interface and it says "Short cicuiting failure" and I do not know why it is sitting there, P.

end of page 59


Posted by: pandaneko Dec 15 2011, 09:46 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 60

Table III-1-2 Connections within Common Power Supply Interface (CI-PSU) and devices/instruments related to this power supply

(here again, I will have to be descriptive, but my taks is made a lot easier than the last page in that there is a fairly recognisable regular structure in the table. I am talking about squares seen on the table. And, if you agree with me about the rough structure):

C1R1: X-band transmitter power amplifier (XPA)

C1R2: (pointing to C1R1) X-band transmitter (TMX)

C1R3: various Heaters

C1R4: (pointing to C1R3 with a thick arrow in red) Heat Control Electronics (HCE)

(Here, repetition accepted and C and R reversed or exchanged)

R4C1 (same as C1R47)

R4C2: Open/Close status monitor

R4C3: Pressure monitor

R4C4: Power for ignition

R4C5: Rocketry measurment (INS-SA)

C3R1: Ultra stable transmitter (USA)

C3R2: Data Recorder (DR)

C3R3: Timer

C3R4: S-band transmitter

C3R5: Solar Proton Monitor (SPM)

(In addition, there are two more squares in the middle area and the one above the other is):

Telemetry Command Interface

and blue dotted line connection to;

X-band transmitter
S-band transmitter
and Beacon mode/Telemetry mode switching circuit enclosed within a square formed by dotted lines

(and the other below it is):

Common Interface Power Supply Unit (CI-PSU)

including all of the red line connections emanating from tis square

Note for the title of this page (additional) is:

Red solid lines are related to power and the blue dotted lines relate to signal switching system

end of page 60

P




Posted by: pandaneko Dec 16 2011, 01:00 PM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

There was a mistake on page 60. C3R1 should have been Ultra Stable Oscillater and with an abbreviation USO

page 61


Table III-1-1 CI-PSU and a list of devices connected to it

(this is a regular table with C3R12 structure. Top row from left to right is Abbreviation::Full Name::Function etc)


CI-PSU: Common Instrument Power Supply Unit: To supply power to the following 10 devices with secondary voltage of +29V, +12V, -12V, +5V

TCI:: Telemetry Command Interface :: To act as a telemetry command interface to a number of common devices

HCE:: Heater Control Electronics:: Heater ON/OFF control and temp. measurement (Heater power is supplied directly from the bus voltage)

DR:: Data Recorder:: To keep data to be sent out to the telemetry system

SPM:: Solar Proton Monitor:: To measure solar protons (usually from 1MeV to a few tens of MeV)


IG-PS:: IGniter Power Supply:: Condensor bank type power supply to provide power to pyros

INS-SA:: INStrument-SAtellite:: Sensor only used at launch, turned OFF thereafter

EPT-SA:: Electrical Programmable Time-Satellite:: Timer circuit, only used at launch and turned OFF thereafter

P-Mon:: Pressure Monitor:: Pressure monitor for propulsive system (imported item)

LVDT:: Linear Variable Differential Transformer:: Latching valve monitor for the propulsive system (imported item)

USO:: Ultra Stable Oscillator:: For radio science measurement (imported item)

end of page 61

P

Posted by: pandaneko Dec 17 2011, 09:42 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 62

fig. III-1-3 Orbital position of Nozomi on the Sun-Earth fixed system

Here, at the centre is the Sun and just to its right is where we are. The only remaining character set on this figure in 2 O'clock position says "Nozomi orbit as seen from the Earth".

End of page 62

page 63

fig. III-1-4 Operational sequence during 24 to 25 April

Note: Netted area corresponds to operational time with Usuda station in Japan. (some 10km from my mountan cottage in central Japan highland!)

(I view this time line to be consisting of 2 columns, one black and the other in red)

(Looking at the black column from top to bottom, still following the times on themain time line):

22:15 MTX_RNG_B (TLM modulation OFF)

02:00 Observation mode change

03:00 Ditto

03:25 Ditto

07:35 TLM editing mode change

07:43 Earth persuit ENA (some kind of enabling activity?, P)

09:00 Earth persuit judgement permitted

10:10 Earth persuit DIS

10:20 TLM editimg mode change

17:37 Time specification CM: TMX_TLM_MOD_ON (TLM modulation)

17:57 Time specification CM: TLM editing mode change

18:32 TMX_TLM_MOD_ON (TLM modulation ON)

18:52 DR REC->STBY

(What follows from here is the column in red, sometimes corresponding to entries in black on the left and there are 5 entries)

1. from 22:15 UDSC LOS to 07:00 is the period in which the failure (or accident) is thought to have taken place.

2. at about 09:00 No action taken* estimated from the reception level on the ground

3. at around 17:00 No action taken

4. at around 18:00 Recption despite TLM modulation being OFF

5. (against 18:32 black entry) No action taken

end of page 63

P




Posted by: pandaneko Dec 18 2011, 09:29 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

Page 64

Fig. III-1-5 Signal reception strength changes from Nozomi received at Usuda (Japan) station's (60m dish)

Unlike normal recption which shows a tendency that strength is max. in the middle and amplitude is min. in the middle we find on 25 April, instead, that strength is decreasing to the right and amplitude is monotonously increaseing.

This corresponds to the situation in which automatic (or autonomous) Earth searching is not being activated (or obeyed).

Characters on the graph is red says "at normal times".

end of page 64

page 65

Fig. III-1-6 Temporal changes recorded by the Solar Proton Detector

Character string in red on the graph says "Time of accident (estimate)".

end of page 65

page 66

Fig. III-1-7 Strength changes since (or after ) year 2000 in the number (?) of high energy particles suffered by Nozomi

Graph above : Average number of counts per every spin (about 8 seconds) of the satellite in a day.

Character string in red says "020421 (data saturated)".

Graph below: Cumulative flux (cmXX2/str) since (or after) year 2000.

end of page 66

P

Posted by: pandaneko Dec 19 2011, 09:29 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 67

Fig. III-1-8 1 bit comms. (communication using autonomous function)

We could regard this to be a table, but for intuitive simplicity I will be descriptive as follows:

top 3 squares from left to right are:

1. setting a question by a command.

2. judgement by autonomous function.

3. Beacon ON command.

Long horizontal line is "Beacon ON" and the short dotted line just below it says "Corresponds to "Beacon OFF" and the character string below says "YES" and the dotted line is "judgement".

end of page 67

page 68

Table III-1-2 Predicted and actually measured values of data on 2 May and 1 bit comms. (operation by ON/OFF beacon signals)

(here, I regard this to be a C5 and R21 matrix and what follows refers only to the tabular entries)

C2R1: Data on 24 April

C3R1: Estimated value on 2 May

C4R1: Actually measued value

C5R2 to R16 is common and it says"Normal except the heater and the common power source".

C5R17: Measued value on 3 May.

C5R18 to R21: cooled to temp. below freezing temp..

end of page 68

P


Posted by: pandaneko Dec 20 2011, 11:43 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 69

Fig. III-2-1 FTA relating to the cause candidates for "not being able to switch to telemetry mode"

(Here, I want to do a few things (experiments) to make sure that what I have been doing is not a waste in the sense of translation quality (?).)

(Here, if I am right, you should be looking at a table (please refer to the original PDF), not a proper table in the sense of it being square in shape, but still retaining its remote hope for being one. My only regret is that I have given R1 to the top header line's row number as you will see in my translation. Actual table elemtns (apart from header line) could have been named from R1 ( In my notation of what folows R1 is denoted as R2, I am afraind), instead of R2 against each column number) (I will also experiment with lines used for squaring off areas used for character strings)

C1R1: Tree top event

C2R1: Primary cause

C3R1: Secondary cause

C4R1: Tertiary cause

C5R1: Judgement reasons

(After this you must be seeing a thick horizontal line separating the header entries above it and the table contents which follows below the horizontal demarcation line)

C1R2: No reception desipite the satellite being in TLM ON mode

C2R2: X 100: Data processing unit mulfunction (X means negative, I think)

(This "X 100: Data processing unit mulfunction" is based on my onw notation and I will seek your comments on the reproduction quality of this particular entry (C2R2) as a member of the larger table. For instance, ":" is simply a short vetical line for seperation between 100 and what follows. For that matter, there is another vertical line in the original text between X and what follows it. Can you see all these features with your 8 bits OS codnig system)

(OMG!, I have lost what I had in mind for further explanation..., but let me continue anyway)

C2R3: X 200: TMX mulfunction

C2R4: X 300: TCI mulfunction

(row numerbs are effective numbers only, not corresponding to the finest row numbers on the extreme right column)

C3R2: (there is a horizontal connection from 100) X 110: Command autonmation sequence mulfunction

C3R3: X 120: Data bus mulfunction

C3R4: X 210: Command recption circuit mulfunction

(horizontal line connection from 200)

C3R5: X 220: Reley device mulfunction

C3R6: X 310: TCI itslef only going bad

C3R7: X 320: Power cut-off

(now we move on to the next column, which is long)

C4R2: X 111: autonomous (or automatic) sequence DISABLE

C4R3: X 112: Devices shrank back to IPL mode

C4R4: X 211: Device internaland +5V system mulfunction

C4R5: X 212 Responsible componetnts mulfunction

C4R6: X 221: Device internal and +V12 sytem mulfunction

C4R7: X 222: Responsible components mulfunction

C4R8: X 311: Responsible components mulfunction

(Herre after column 5 entries, only row numbers)

C5R2: We sent the same sequence of commands as REAL, but we could not confirmt its outome.

C5R3: after starting up the devices once again, we sent the same related sequence command, but we could not confirm its outcome.

C5R4: We were able to confirm that regular outcome of the command XPA ON and OFF and there was no reason why some other commands copuld not be accepted and executed acccordingly.

C5R6: Ditto

C5R7: Ditto

C5R8: Same as R5

C5R9: Same as R6

C5R10: Power source (CI-PSU) for TCI is the same and is commonly used for the heater control system. Therefore, it is accepted that the POWER OFF led to freezing of propulsive materials and further leading to inability of keeping the Earth in view.

Also, POWER OFF can explain all othe events.

C5R11: Analyses later showed that the time ellapse between POWER OFF and actual freezing was 2 hours at maximum, but this itself does not negate any of the operational sequence.

end of page 69

P




Posted by: pandaneko Dec 21 2011, 11:27 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of refernce

page 70

Fig. III-2-2 FTA relating to cause candidates for "CI-PSU not being put into ON as required" (part 1 of 2)

(In what follows you will see the sort of difficulties I am having with this particular figure and with others on several fronts. Unlike all other figures so far this figure turned out to be a picture. I was very pleased with this finding and copied it and tried to paste it into this page for ease of translation for myself. It did not work. It perhaps is this forum's policy not to allow simple picture pasting?

So, I ended up handwriting everything within this figure for retyping in here. I do know that I can open up more than one internet pages for work on my display unit, but in reality I will find it difficult to cope with. Anyway, back to this picture figure in question. Because it is a picture, obviously photo-reduced from a much larger original figure which was converted into a picture,
characters on it are very corrupt. You may say enlarge them, but if you do the same corruptnes is enlarged. So, my translation will be sometimes bad, to say the least.)

(Here it goes, and without using row numbers, and the top header line first)

C1: Tree top event
C2: Primary reason
C3: Secondary reason
C4: Tetiary reason
C5: 4th reason
C6: Reason for judgment

(Now, I am coming on to the main figure entries and start using row numbers in line with the number of rows in C6, which will act as reference row numbers without disruption or vacancy between entries in this C6 column. Unlike previous page, R1 here refers to the very 1st row entry, ignoring the header line above them.)

C1R1: Circle: CI-PSU cannot be put into ON state.

(This leads on to 4 tree elements (or squares in the picture if you can recognise it as such), or branches in C2 as follows. Also, a vertical line pointing down from the intersection between C1R1 and C2R1 ppoints to the next figure to follow on page 71.)

C2R1: Cross: 100: PSU limitter?, or resetter?, or reactor? bad action (or failure, or failing). (Here, ? means "uncertain in my recognition of the characters to be read")

(You may actually find more reasons for them to be something more meaningful as my translation continues)

C2R7: Cross: 200: PCU-CU-PSU + (plus) somehing I cannot recognise at all

C2R8: Triangle: 300: CI-PSU bad action (or failure)

C2R12: Cross: 400: CI-PSU device + something I cannot recognise

C3R1: Cross: 110: PCU whole function mulfunctioning

C3R2: Cross: 120: Commanding function mulfunctioning

C3R4: Cross: 130: Limitter? function not functioning

C3R8: Cross: 310: Voltage control not functioning

C3R10: Triangle: 320: Secondary system not functioning

(Actually, just thinking about the picture property of this figure, I am beginning to suspsect that most of the 1.09 Meg of this report might be coming from these pictures. Perhaps not, because these are one layered B/W pictures...)

C4R2: Cross: 121: Logic circuit for commanding failure

C4R3: Cross: 122: "something" ON command output failure

C4R4: Cross: 131: detection register (or resistance) "something" failure

C4R6: Cross: 132: OP amp. gain increase

C4R7: Cross: 133: Comparator failure

C4R9: Cross: 311: Switching TR failure

C4R10: Cross: 312: PAM control failure (I may be wrong here)

C4R11: Triangle: 321: One or more components failure

C5R11: Triangle: 321A: Accidental failure

C5R12: Cross: 321B: Bad soldering of components (Here, if you find a smiley after 321, it is a capital byee)

C6R1: Apart from the yet-to-be done "batch something" after the accident there is no mulfunction outside CI-PSU On/Off function

C6R2: Other commands by the common F?PCA (On/Off in other systems) are functioning properly and it is hard to imagine that only an arbitary function is affected.

C6R3: Ditto

C6R4: In the line in question there is a built-in function whereby FMT, or TMT, or FET switch is turned off in the event that a limit is exceeded on comparison of detected current value and the limit value (or reset value)

If the detection register or resistance fails on "release (infinite impedance as I suspect)" then secondary output is terminated in theory. However, in this case in hand there was an imperfect secondary output reported.

C6R5: This will only occur if the input register (or resistance) fails, or on "something register" "release (infinite impedance?)" fails

However, register failure in a very minute current circuit is unthinkable.

C6R6: 4 system functions are all integrated into the same comperator layout and it is very hard to imagine that only a particular function failed.

C6R7: This is "something" inside the satellite and it is very hard to imagine that it failed accidentally after 4 years in service in deep space.

C6R8: This can be denied in view of the secondary output.

C6R9: Here, do not forget that we are talking about 17 ceramic condensors.

C6R10: Failure mode of the soldered parts after years of service in space use is not "something", but "relaese (and I suspect this to mean infinite impedance)

C6R11: Same as C6R7 and it may be that the said "something" may be WHN... I do not know what WHN may mean, though.

end of page 70

P













Posted by: Paolo Dec 21 2011, 01:08 PM

thanks panda, I look forward to your translations every day!
by the way, is there anybody who wants to collect them in a proper document? I would do it myself, but I'm too lazy...

Posted by: pandaneko Dec 21 2011, 01:44 PM

QUOTE (Paolo @ Dec 21 2011, 10:08 PM) *
thanks panda, I look forward to your translations every day!
by the way, is there anybody who wants to collect them in a proper document? I would do it myself, but I'm too lazy...


Thanks, Paolo. If that somebody is watching these posts regularly you may eventually come into contact with him (or her) and in fact you may jointly pose further questions to me for action.

I might also add at this stage, that I will be wanting to explain, in the season's spirit, why I am bothered at all by this issue of 8 bits or 16 bits coding. I just hope that Admin will allow me to spend some time (space, and not a lot at all) on it as an exceptional posting. It is after all Merry Christmas, is it not? P





Posted by: elakdawalla Dec 21 2011, 05:52 PM

I was thinking that a way to make good use of pandaneko's translations might be to set up a multi-author blog and have volunteers match original slides to his translations as blog posts. This is something we'd be able to set up on the Society website after our upcoming redesign, but I'm pretty sure we could also just ingest an existing wordpress blog if someone wanted to get started on the project before.

Posted by: pandaneko Dec 22 2011, 10:56 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 71

(This page is even worse than page 70 in that the extent of photo-reduction is much larger as the number of rows in the last column is now 19, compared with 11 on page 70, making almost all of entries impossible to decipher, but I will do my best.

In the meantime, I forgot to mention something with page 69. There is an arrow pointing upward from C5R11 to C5R10.)

Fig. III-2-2 FTA relating to cause candidates for "CI-PSU not being put into ON as required" (part 2 of 2)

(This figure is effectively a 6C and 19 R matrix. Header entries from C2 to C6 are the same as on page 70. C1 header is continuation, I think and there is no entry in C1 column at all.)

C2R1: Circle: 500: CI-PSU XXX (here, XXX means impossible to recognise characters in this space)

(and entries in C3 all come from C2R1 and they are):

C3R1: Cross: 510: ?PS XXX (here, ? means there is something in this space which cannot be recognised)

C3R2: Cross: 520: S (or 5)PM?, XXX

C3R3: Cross: 530: EPT-SA XXX

C3R4: Triangle: 540: WS (or 5)-SA XXX

C3R6: Cross: 550: DR XXX

C3R7: Triangle: 560: TC XXX

C3R12: Triangle: 570: HCE XXX

C3R17: ***: 580: LVDT XXX Here, *** is a character string, not a circle nor triangle. I strained my eyes and I still could not recognise what it is)

C3R18: ***: 590: USO XXX

C3R19: ***: XXX: pressure sensor XXX

C4R1: Cross: 511: XXX ( and this XXX will be the same in all rows of this column)

C4R2: Cross: 521: XXX

C4R3: Cross: 531: XXX

C4R4: Cross: 541: XXX (and this and the next entry comes from Triangle: 540 in C3)

C4R5: Triangle: 542: single event upset

C4R6: Cross: 551: XXX

C4R7: Triangle: 561: XXX

C4R12: Triangle: 571: XXX

C4R17: ***:581: XXX

C4R18: ***: 591: XXX

C4R19: ***: 5A1?: XXX

C5R7: Triangle: 561A: total dose effect

C5R8: Triangle: 561B: single event latch up

C5R9: Triangle: 561C: latch up by discharge

C5R10: Triangle: 561D: accidental

C5R11: Cross: 561E: bad soldering job

C5R12: Triangle: 571A: total dose effect

C5R13: Triangle: 571B: single event latch up

C5R14: Triangle: 571C: latch up by discharge

C5R15: Triangle: 571D: accidental

C5R16: Cross: 571E: bad soldering job

(and the last column entries are all too bad. There are entries in R1 to R9, R11 to R14, and R16 to R19. It is possible to read a few characters in any of these entries, but this column, giving reasons, contains much larger number of character strings and it is no use to be able to read here and there and translation will be bound to be wrong)

end of page 71

This is perhaps a good time for me to mention the coding issue which has been tormenting me, a particularly acute problem if I am facing a table. I will try to be as succinct as possible.

My ancesters did not have characters and burrowed them from China (Thank you! China) Making the story brutally simplistic, Chinese characters are all pictures (hieroglyphic), made up with a lot of strokes. So, the usual 8 bit coding system cannot cope with the complexity. We therefore need 16 bits and I have no idea why they do it, but they here use the 16 bit system for coding (simpler) alphanumerics as well.

Result is confusing. 16 bit alphabets are OK as they are of the same shape, but simply "fatter" in appearance, but numbers look deceptively similar. My problem is tables. Are the numbers in the table 8 bit coded or 16 bit coded? For that matter, are the line elements, forming the frame of tables, are they what they look like, or not?

My assumption so far is that people who made these tables used 8 bit coding for alphanumeric entries. The only way to check is to copy a table (not a picture table, but text table) for experiment. I meant to do that yesterday, but faced with the picture table not wanting to be pasted here I did not managed to do it. I will try again when all of the translation work comes to an end.

Now, what follows is an extra for your Christmas conversations.

So, characters came from China and you want to write, say, "I eat an apple".

What my ancesters did was to put "I- like picture, Eat- like picture, Apple- like picture". They, however, made a fatal mistake in all this because "XXX-like pictures" were all chosen for their sounds, not understanding each is a picture. Chinese naturally pointed out that above sequence actually reads "You drive a cow". Here, of course, this is only by way of explanation.

So, my ancesters eventually allocated the right pictures in the right places. But, they did not like it at all. Too many strokes! So, they decomposed Chinese characters into components and came up with 2 phonetic sets of characters. Had they stayed with these two sets only my current problem should not be existing.

In reality they decided to retain a portion of these Chinese pictures as well. So, our current writing system is a mixture of phonetic and hieroglyphic characters. This is why 16 bit coding system is used here and how my dilemma started.

Merry Christmas from Pandaneko to all of my colleagues and all those space probes out there in deep space!






Posted by: pandaneko Dec 23 2011, 09:36 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 72

Fig. III-2-3 Bus system voltage and current at the time of flares

(The only caption here is indicated by red lines and it says):

No change is seen in the portions indicated (by lines in red)

end of page 72

page 73

Table III-2-1 Accidental failure probability in space use by component types (quality assured level at class S)

(This is a C4 R many matrix. The only captions to be translated are):

C3R1: How many years before accident? or Accident every how many years?

C4R1: Occurrence rate of short cicuiting mode (for information only)

Note: FIT is the number of failures in 10 to the power of 9 years

end of page 72

Page 73

Table IV-2-1 Measures to be taken for the cause candidates which this time have been rated low (With Nozomi measures have been taken)

(This is an easy C2R6 matrix.)

C1R1: Cause candidates
C2R1: Measures to be taken

C1R2: total dose
C2R2: choose components which are most approapriate for the environment in use

*: initial sign of total dose is a small increase in current and this itself will not easily lead to "lost functions". We must therefore ensure that current limitters will not react prematurely.

C1R3: single event upset (SEU)
C2R3:

1. regular patroling and provision of refreshening function
2. triple redundancy for important registers
3. robust control logic (eg. automatic discovery of imvalid data)

C1R4: latch up
C2R4: choose radiation hardened components

C1R5: charging up
C2R5: Get rid of conductive layers which are not earthed

C1R6: high voltage discharge
C2R6:

1. isolation of vulnerable systems (eg. surrounding by secondary ground, primary and secondary isolation)
2. installation of imprinted voltage variables

end of page 73

P



Posted by: Astro0 Dec 23 2011, 09:42 AM

That's a great story about the 16-bit coding biggrin.gif
Thanks again for all the translation work this year.
A very Merry Christmas to you and your family.

Posted by: pandaneko Dec 24 2011, 10:19 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 75

Table IV-2-2 Means for seperating out failure causes and their characteristics

(This is a C3R6 regular matrix inluding the headers in row 1)

C1R1: Failure cause seperation means
C2R1: Meritts
C3R1: Demeritts

C1R2: Resistances
C1R3: Fuses
C1R4: Relays and limtter circuits
C1R5: FET switches and limitter circuits
C1R6: Ideal redundancies

C2R2: system is easy and repetitive activations are possible.

C2R3: Setting up is easy.

C2R4: Repetitive activations are possible.

also, cancelling of latching up is possible.

There is a possibility to save components from temporary shortciruiting.

C2R5: Repetitive activation is possible.

There is no limit to the number of activation.

also, cancelling of latching up is possible. There is a possibility to save components from temporary shortciruiting.

It is very easy to set the system to OFF side without fail at the time of power on.

C2R6: It is possible to accept, at least once and perfectly as well, every possible failure mode.

C3R2: Need heat resistance at times of short circuiting.

Given voltage drop we may find it difficutlt to use this as "load current" may fluctuate.

C3R3: Once activated it will remain in the same state forever.

We need to check anti-vivration characteristics at launch times.

Action possible region is generally fairly narrow in that it will function without being affected by a sudden surge etc, with a current which will not affect other devices.

C3R4: Composition is very complex.

Relaying system itself needs watching out for failures and there is a limitation on the number of possible actions that can be taken.

If the relay system is of a "latch type" it may not improve the situation if:

1. there is another breaker downstream and
2. response speed upstream is slow

C3R5: Composition is very complex.

We need to allow for:

1. some extent of voltage drop
2. some extent of heat generation

C3R6: Impact on heavy resources is largest (I have no idea what they are talking about, P)

If we want to introduce cross-redundancies it will lead to the system getting very complicated and we will have to be extremely careful in design and verification.

We will need to evaluate its usefulness against the failure rate of similar redundant systems if:

1. the vulnerability against failure is very localised and/or

2. if the failure rate in question is very low in the first place.

end of page 75

P

Posted by: pandaneko Dec 25 2011, 09:36 AM

QUOTE (pandaneko @ Oct 23 2011, 06:12 PM) *
http://www.mext.go.jp/b_menu/shingi/uchuu/reports/04061101.pdf


above for ease of reference

page 76

Table IV-2-3 Concrete examples of failure seperation methods

(Inside the top horizontally oblong square says):

Large characters and those enclosed inside ovals are the points of improvements made with Nozomi

(However, I do not find any large characters on this page and next. There are, however, characters shown in red toegther with lines in red as you will see)

(There are two system outlines on this and next page, one on left and the other on right)

(One on left here says): Nozomi's system outline : current

(the only other characters for translation here is inside the top of 3 boxes next to TCI and it says): "Pressure monitor".

(the other one on right here says): Nozomi's system outline with improvement plan (1): Protective resisters in case of Black Box failure.

(the only other characters for translation here is inside the top of 3 boxes next to TCI and it says): "Pressure monitor".

end of page 76

Page 77 (system outline continuued)

(One on left here says): Nozomi's system outline with improvement plan (2): Protective resisters in addtion to switching between CI and PSU ( as indicated by vertically long square in red) + 1 kg in weight ( and the characters in this square says):

"Power control motherboard (within TCI)"

(the only other characters for translation here is inside the top of 3 boxes next to TCI and it says): "Pressure monitor".

(the other one on right here says): Nozomi's system outline with improvement plan (3): Protective resisters in addition to individual power source for every device (+ 3 kg in weight)

(characters in the square above LVDT next to TCI-2 box in red says): "Pressure monitor".

end of page 77

P

Posted by: pandaneko Dec 26 2011, 10:09 AM

QUOTE (pandaneko @ Dec 25 2011, 06:36 PM) *
end of page 77


I now realise that I have effectively come to the end of translation work for this particular document. There are some more pages including pages 79 to 81 which are glossary pages in English and Japanese and very useful for any future correction work.

However, just glancing at these pages I note with satisfaction that I have not made fatal mistakes in the choice of my wordings.

Other pages are irrelevant to the story of this failure and need not be translated.

For now I may take up to 10 days of break in view of the inevitable events coming up over the next 2 weeks or so. However, it does not mean that I will not be able to grab time to do what remains to be done even during this period. It is just inpredictable.

When I resume the first document will be the JAXA press release summing up the causes of failure.

P

Posted by: pandaneko Jan 13 2012, 10:13 AM

QUOTE (pandaneko @ Dec 26 2011, 07:09 PM) *
When I resume the first document will be the JAXA press release summing up the causes of failure.


What follows is the press release. I will provide link info and any other info later. Also, I am not exactly sure if this will be useful and I may not be able to complete translation of the whole of this release this evening and in which case I will continue tommorrow on with the rest. Here, we go as follows.

About abandoning insertion of Nozomi into Mars circular orbit

10 December 2003, JAXA

We reported on above subject to Space Activities Comission (SAC) held today as follows.

1. Current status

1. Mars probe Nozomi (launched July 1999) (fig. 1) developped a mulfunction in the fuel supply system at the time of leaving the earth gravitational fields (20 December 1999) (mulfunction history shown in seperate paper 1) and we had to change the original orbital plan and the arrival had to be changed from October 2000 to December 2003.


• 1st Japanese Mars probe launched by ISAS, carrying instruments from Sweden, Germany, US and Canada, also in cooperation with France.

• Launched by M-V 3 solid fuel rocket on 4 July 1998 from Uchinoura Space Observation Centre of ISAS in Kagoshima prfecture.


• Main objectives: Interaction between Solar winds and upper utmosphere of Mars

(Martian magnetosphere, atmosphere, plasma composition, satellites)

• Nozomi has been in its final approach into Mars since June of this year. EAT is 14 December.


Fig. 1 Outline of Mars probe Nozomi (Planet cool.gif


2. A mulfunction developped in April 2002 in the comms. and thermal protection systems, resulting in minimum amount of communication in addition to incapability to perform temperature control. The mulfucntion here refers to thoes events as shown in Fig. 2 whereby part of the series of the circuits meant to supply power from common sources of power to components developped short circuiting.


Fig. 2 Nozomi power supply, schematic outline

3. May 2002 we tried to stablise probe temp. by turning on instruments. Also, we made a restoration work by trying to burn out the short circuiting sections by directing currents. However, this operation resulted in total loss of communiction capability.

4. July 2002 we kept trying to recover comms. for two months based on the findings of trouble shootings and achieved a minimum level of communication capability.

5. August 2002 fuel temp. reached that of fuel defreezing temp. This was due to the decreasing distance between the probe and the Sun and also the heat generated by the instruments on board. From here on we managed to control fuel temp. by keeping the right probe orientation.

6. June 2003 we managed to insert Nozomi, using the bare minimum communication means, into its final transer orbit.

7. July 2003 we needed precise orbital determination and firing of the main engine. This meant that we had to restore thermal contorl system and the work began as required. Unfortunately, this work yet again led to the total loss of comms.

8. From July 2003 to today (December) we have been trying to burn out the short circuiting sections by directing currents to there, and this meant that the number of times we turned on the common power source reached 1.3 times 10,000,000,000.

We also tried to rewrite the ROMs on board in order to exclude the possibility of the onboard computers going bad to no effects. Based on this we returned the ROMs to their initial values and continued with "continous ON" operation, but there is no prospect of recovery on the night of 9 December.


9. All this made us persuade that insertion into Mars orbit was no longer possible and we began the process of work required to make sure Nozomi will avoid collision into Mars on the night of 9 December in accordance with an international agreenment (collision probability is less than 0. 1% as required)

For your reference current orbital plan with insertion in mind is shown in Fig. 3 and that of fly-by is shown in Fig. 4. As you can see from Fig. 3 continuing with the current orbital plan with a fly-by will mean just a slight acceleration by Mars gravity and lead to a clser approach to Mars.


NOTE) COSPAR planetatry protection policy and moral obligation to observe its policy



Fig. 3 Nozoni's original orbit

Fig. 4 Nozomi's Mars orbiting plan and its fly-by orbit


(This will continue, not by very much, though)

P

Posted by: pandaneko Jan 14 2012, 10:15 AM

QUOTE (pandaneko @ Jan 13 2012, 07:13 PM) *
(This will continue, not by very much, though)
P



What follows is the translation of the "seperate paper 1" mentioned in the last entry. I am afraid I cannot paste the URL yet of this report as I do not wish to loose what has been copied for this entry. I will do that tommorrow.

Seperate paper 1

About giving up the hope of inserting Nozomi into Mars circular orbit



History of Nozomi's mulfunctions. Mulfunction of this time

20 December 1998

Escape from Earth gravity to the mulfunction in which not enough propuslive power was achieved


Causes:

Too much fuel had to be used because the valve upstream of the oxidiser tank had not been fully opened (note 1), leading to much less propulsion than expected. The valve in question was what had been specifically employed in order not to allow reverse flow of the fuel and oxidiser vapours upstream as precaution given the US Mars Observer's trouble.


Measures taken:

It was discovered that it was not going to be neccessary to close the above valve in order to stop the reverse flow given the amount of remaining fuel after Earth escape operation. It was therefore decided that we will open the above valve during the visible operational period on 21st and keep it opened during the rest of our operation.

Influences:

We had to give up our originally planned Mars insertion operation due to take place in mid October 1999 and had to delay it until sometime between end December 2003 to early January 2004. (Subsequent orbit optimisation led to the time of arrival to be 14 December 2003.)


26 April 2002: Signal came in as a beacon signal (*1) (trouble at this time)


Causes:

Short circuiting had developped in parts of the secondary circuit of the common system power source (CI-PSU) and it is estimated that this was due to the high energy particles in the wake of the massive solar flares on 22nd (maximum as far as Nozomi was concerned).

Influences:

We were no longer able to send data from Nozomi to the ground because there was no power. In addition, the thermal control circuit was not active. (It was later discovered at the end of April that the fuel had been frozen at the time of 26th.)

Measures taken:

3 May 2002:

We turned on instruments one by one so that satellite temp. could be improved. Thermal analysis told us that the left-alone- attitude operation will lead to natural defreezing in September.

15 May 2002:

We lost beacon wave reception due to continuous sending of "ON commands" to the sections concerned.


• It is thought that the X-band transmitter's relay circuit caused a mulfunction (to OFF) due to the imperfect start-up of the power source for the ICs meant for command distribution. (Both ON and OFF commands were issued at the same time)

• Ground tests showed that different relays will behave differently and this presented the possibility of recovering the beacon communication by issuing a one-off command meant specifically for the power source in question.

Measures taken (before report acceptance?):

15 July 2002:

After some 7500 trials beacon communication was back.

End August 2002:

Fuel defreezing temp. reached -> after this we kept attitude control for this state so that fuel freezing will not occur again.

20 December 2002:

1st Earth swing-by

19 June 2003:

2nd Earth swing-by

Since 5 July 2003:

Short circuit section's burn out operation by keeping CI-PSU permanently ON. During this process total loss of beacon communication on 9 July.

From 2 October 2003 to around 20 October 2003:

Rewriting of the contents of the memory on board in order to exclude the possibility of the mulfunction of the DHU on board (*2)


From 23 October 2003:

Re-starting the operation for burning out the short-circuiting sections by continuosly issuing commands by CI-PSU.


NOTE 1:

Looking into the causes of the valve mulfunction we now know that it is almost certainly due to the increased resistance to the sliding motion at the sliding section due to incompatibility of materials used at that section.


*1

Beacon state: Signals are sent out by the satellite, but no data is carried on these waves.


*2

DHU: the most important computer on board, for evrything.


End of this press release

P

Posted by: pandaneko Jan 17 2012, 10:11 AM

What follows is the URL of the press release of JAXA on Nozomi's failure.

http://www.jaxa.jp/press/2003/12/20031210_nozomi_j.html

About this coding business I have been thinking about it for the last three weeks. Simplest would be to experiment. Here, I will switch on my hardware switch to write "1 A" using 16 bits coding. What goes before that is "1 A" with 8 bits coding.

1. 1 A with 8 bits coding: 1 A

2. 1 A with 16 bits coding: 1 A

With 2. above, I actually added one space with 16 bits coding and that may complicate this issue, but not by much, I hope...

If you can read them both without any problems, then I can forget about my worries about this, except that there might still be cases where the person(s) who wrote the whole thing may have used the mixture of 8 and 16 bits codings without consistency.

This is not a small matter of concern. On placing mail orders, for example, your order may be rejected. It does happen, here, often...

Pandanakeo

Posted by: pandaneko Jan 19 2012, 08:28 AM

What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".

This is entirely in accordance with the purpose of my translating relevant files for the advancment of future missions and I am very pleased that I found this particular file for the communities with interest.

Translations will follow shortly. The original file consists of 4 contributions made by the same person and each may take up to a few times of translation. I will not be identifying the name of the person who wrote these pages.

P

Posted by: pandaneko Jan 20 2012, 09:06 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".

This is entirely in accordance with the purpose of my translating relevant files for the advancment of future missions and I am very pleased that I found this particular file for the communities with interest.

Translations will follow shortly. The original file consists of 4 contributions made by the same person and each may take up to a few times of translation. I will not be identifying the name of the person who wrote these pages.

P


In what follows I am translating this document chunk by chunk as I see fit for the purpose because there are no page numbers as such.

Nozomi left the Earth on 4 July 1998 and travelled across the solar system for over 5 years carrying signatures of hope from more than 270,000 people. I regret to say that we had to teminate the operation of Nozomi at 20:30 on 9 December 2003 (Tuesday) despite the frantic efforts by the team upon confirmation that we had not been able to fix the faulty portions of the system.

Consequently, we kept sending out a command to Nozomi from 20:45 until 21:23 on the same day in order to reduce the possibility of Nozomi colliding with Mars. As a result, Nozomi passed, on 14 December, the height of about 1000 km from the surface of Mars and left the gravitational field of Mars to continue its journey across the solar system once again.

Nozomi, the first of its kind ever launched by Japan, has encountered all kinds of difficulties over the last 5 years as had been expected, had to terminate her mission within the last few steps from her success.

Granted that Nozomi, as Japan's first planetary mission, was not able to achieve the maturity as is now taken for granted in other areas such as X-ray astronomy and space plasma physics we nevertheless think that the lessons learnt from operating this spacecraft in the frenzies of it all during the last 5 years must be told to the rest of the world so that our future planetary missions will benefit from the difficulties Nozomi encountered.

I believe that it is the duty of our group to do just that. We were endowed with the resources for that purpose. We must reflect upon failures. That is the only way foward. Both US and Soviet Union have sent more than 30 spacecrafts to Mars to date and 20 of them have failed. (Is this really, really true?, I doubt it, P) We will have to learn from failures. That is the only way forward.

Learn from successes, ride over the faults we found, it is not regrets, not masochistic either, at all, and we can only do forward looking investigations for the humanity.

P

Posted by: pandaneko Jan 22 2012, 12:57 PM

QUOTE (pandaneko @ Jan 20 2012, 06:06 PM) *
Learn from successes, ride over the faults we found, it is not regrets, not masochistic either, at all, and we can only do forward looking investigations for the humanity.


One chunck after above just before two graphs is as follows.

1.On the subject of engineering aspects

There are 4 Japanese spacecrafts which have left the Earth gravitational fields. The first one is the Halley probes, Sakigake and Suisei launched in 1985, then Nozomi, and Hayabusa which is the latest departing in May 2003. However, of all these, Nozomi is the only one which specifically targetted a planet as its destination.

Given limited human resources and finance, very tight scheduling it has been a very challenging task to try and reach a planet. It has been fun, too, of course, with all those technologies to prove in orbit.

First of all, we had this mission analysis. We have gained quite a lot from trying to trade off an innumerable number of engineering aspects in an effort to obtain the maximum benefit from an optimum flight scenario for Nozomi.

I think we have secured the solid foundation for orbital desine and operation technologies, in addition to the experience gained during the flight of Hiten which was launched in 1990, making use of swing-bys with the Earth and the Moon.

Needless to say that we were all very much encouraged and impressed by the frantic efforts shown by this "Orbit and Mission" team, sacrifysing the period non-stop, from Christmass through to the new year period in the face of fuel depletion in the wake of the Earth swing-by in 1998. The heroic dedication that they showed in coming up with a renewed mission plan was a ray of hope for the Japanese space science and technologies.

End of this chunck and this is followed by schematics. I am unsure as to what I might do about them, yet. P


Posted by: pandaneko Jan 23 2012, 09:16 AM

QUOTE (pandaneko @ Jan 22 2012, 09:57 PM) *
End of this chunck and this is followed by schematics. I am unsure as to what I might do about them, yet. P


With these two schematics my contributions are minimum and it shouod suffice. The first one on the left is all in English. The second one on the right is more or less self-explanatory. I might add that red is Mars, purple is Nozomi and the green is the Earth. What follows after these graphs is as follows.

Next is the technology for determining the orbit very accurately. We have obtained these technologies and trained ourselves in them from the interactions between the ground based commands and the responses from the spacecraft so tha we now know how we can determine orbits in deep space, line of sight distance, velocity data etc. to put them into an extremely precise dynamical model

Also, autonomous technology. Sometimes, it takes as much as 20 minutes by the radio waves to reach the spacecraft. Therefore, a lot of decisions are left for the spacecraft to make by the onborad computers. We managed to gain a limited amount of insight into the workings of "autonomous decision makings". This experience was put into a maximum use in the case of Hayabusa.

In short, we have obtained a maximum experience from our attempts with perational know-hows and use of relevant communication means to keep communications alive over the distance of more than 3.7 times 10 to the power of 8 km using our 64m diameter dish at Usuda station in central highland area of Japan.

end of this particular chunck. P


Posted by: pandaneko Jan 24 2012, 10:07 AM

What follows is the chunck immediately following the reference to the deep space antenna located in the high land area in central Japan where my family's mountain cottage happens to be only 10 miles from it!

We have also gained a lot in our attemtps to reduce inertial mass of instruments on board. Planetary exploeres need a lot more energy at launch compared with earth circulating satellites. Electronics, cells, antenna, solar batteries, propulsion systems, all these called for new technologies for reduced mass. We believe that we cleared all these hurdles with Nozomi.


(There is a schematic of Nozomi after this, but it should not be a concern to our colleagues. So, I will skip translation here.)


We had not expected to be involved in such a lengthy operation, including a long cruising phase. Under these circumstances, we had to operate very safely given all kinds of constraints and that meant that a lot of the ground support software had to be turned into AI capable, and that brought to us lots and lots of precious experiences.

All this gave us quite a lot for the operation of Hayabusa and all other future planetary missions. On the other hand, there is one notable point of regret in relation to the valve we had incorporated into the control engine in the wake of the US Mars Observer's bitter experience.

What started Nozomi's agony was the half opening of the shut valve which had been put in the downstream of the reverse flow stop valve in the gas supply line which was meant to pressurise the fuel and oxidiser tanks. Other people's experiences are hard to digest.

We did mean to have learnt from the US experience and we might have installed unneccesary redundancies into our system, or did we? In any event, we will need to spend a lot of time looking into the operational aspects of this and all other relevant pitfalls we might have fallen into.

We also have this short-circuitting issue, following the direct hit by solar particles. There have been many failures to date due to these large scale solar flares. We believe that recent explosions crippled at least a dozen spacecrafts worldwide. We cannot afford to say that ours had been up to the international standard for this kind of troubles. We will have to come up with solutions once and forever.

There are two points here, which we need to examine very carefully.

One is that our original design had been such that a command sent to the short-circuitted portion will automatically bring about an exccessive current, activating a circuit breaker, leading to an immediate loss of the current. However, if you come to think about it this particular breaker had been installed there in the first place to protect the whole circuit. We had the reverse effect of this precaution.

Sure, it may be impossible to take everything into account. However, this reverse effect issue, be it with the valves, or breakers, does and will continue to happen, I think. Many other missions of this kind worldwide have seen this "reverse effects" cropping up almost constantly.

It may well be that there are more than one way of making the maximum use of this experience with the breaker. I can say, at least, that we are that much cleverer now as a result.

Second point of possible arguements is this. This particular circuit had been meant to control both telemetry modulation and the heater for control fuel. Granted that this was due to the utmost need to reduce inertial mass. However, if one of the two had been alive for use we might have found a way to come up with a solution. I am sure that this will be one of the focuses of arguments from now on.


As the first of our planetary missions Nozomi left a lot of issues for us to ponder over and come up with viable solutions for. I am sure that we will be willing to spend time on these issues for many years to come.

end of this chunck. P

Posted by: pandaneko Jan 25 2012, 09:47 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


What follows is the start of the part 2 of this 4 article series. This is immediately followed by the Lyman aplha schematic.


2.About science observations

Nozomi had in total 15 different means of observing the Mars. Following the trouble with the Earth swing-by in 1998 and the period following it for 5 years in wait mode with Sun-centric orbits we made a lot of scientific observations, mostly to check up on the health of the instruments on board, and some of these included very unique observations.

Mars camera (MIC) sent us a two-shot view of the Earth and the Moon in July 1998. This particular photograph did not have any value to professionals and exterts at all, but once it was carried on newspapers it brought in a lot of emotional responses from the general public. It is a kind of " memorial snap shot" of friendly planets, all travelling in the vast expanse of the universe.

Also, Nozomi became the first space probe sent by Japan to have a look at the other side of the Moon for the very first time in history.

Nozomi's ultraviolet spectrographic camera made measurements on the hydrogen Lyman alpha line in the interplanetary space. Hydrogen Lyman alpha radiation from the Sun is scattered by the neutral hydrogen atoms floating in the interplanetary space and lights up the space.

It reminds us of the fact that the air-molecules surrounding the Earth scatter the solar ray, producing the beautiful blue sky for us. Where do all these hydrogen atoms come from? They originate in the material flow called "interplanetary wind" in our galactic system.

This interplanetary wind, as it approaches the Sun, is ionised by the energy of the solar wind and the ultraviolot component of the Sun's radiation. Thes ionised hydrogen atoms will no longer scatter hydrogen Lyman alpha light and the less condensed, by ionisation, interplanetary wind will continue its travel downstream.

It is for this reason that the Lyman alpha light looks stronger in the direction from which it is coming and darker in the opposite direction. From the observation made by Nozomi of the hydrogen Lyman alpha light distribution and its intensity in the interplanetary space we are trying to study the properties of the Solar wind causing all these changes.

End of this particular chunk. P

Posted by: pandaneko Jan 26 2012, 09:33 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


The previous posting is followed by a schematic called " Internplanetary hydrogen alpha light intensity distribution" (please refer to this with above URL) and what follows comes right after this schematic.

Charged particles are constantly trying to flow out from Earth ionosphere. These particles, however, are trapped by the Earth's magnetic field and unless there are huge disturbances in this magnetic field they cannot hope to escape into space. It has been thought that these "cold (not energetic enough) charged particles are trapped by the magnetic lines which on average pass at the height of about 4 times of the radius of the Earth in the equiatorial plane.

90 % of these trapped particles are hydrogen ions and the rest are mostly helium ions. It is these helium ions which refelect the ultra viloet lgiht radiated the Sun.

Nozomi's XUV, the Extreme Ultra Violet telescope, had the first glimpse of this region for the first time from outside. Nozomi's obervation showed that a lot more than imagined amount of helium ions are leaving from this region into outside space.

(There is an image right after this, which can be enlarged on clicking)

Nozomi's MDC, the dust counter, started its measurement soon after launch in July 1998 and continued its operation for nearly 4 years until April 2002, looking at the space surrounding the Earth and also interplanetary dust velocities and masses.

Nozomi recorded about 100 clear dust collisions over the 4 year period starting with the first identification of a constellation (I may be wrong with this translation, P) on 11 July 1998. Most of these dusts measured by Nozomi's MDC are thought to be originating from asteroids and commets in their Kepler circulation orbit, but some are thought to be clearly originating from outside the Solar system.

In 1999 Nozomi measured at least 4 extra galactic high velocity dusts. Of these, 2 of them had their velocity vectors coinciding with those of the velocities and ditrections with which the Solar system moves relative to surrounding interplanetary gasses. It is therefore thought that these are dusts coming from the interplanetary region.

The fact that these extra solar system dusts were ever measued within the Earth region is one important contribution to our knowledge.

(end of this chunck, P)

Posted by: pandaneko Jan 27 2012, 08:44 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


What follows is the start of the part 3 of this part 4 series of newsletter by ISAS. I am first translating the captions contained in the very first schematic titled "Electron Spectrum Analyzer/Nozomi". They are as follows.

"Electron velocity direction in the ecliptic frame of reference" is directly on the schematic. Within the schematic itself, the caption around the dot in red says "Solar wind electtrons" and the one on the right to it says "Electrons from the Moon".

Red dot means the direction of the sun and the asterisk looking-like symbol is the magnetic lines. Disk like thing is the shadow cast by the Moon and its tail.

Now, what the chunk at the start says:

"Now, it seems I cannot paste what I copied. Instead of loosing above translation I will let this go first and upload the translated chunk seperately, P"


Posted by: pandaneko Jan 27 2012, 09:52 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


Nozomi made observations during the time of the Moon swing-by. This was in order to look into the plasma environment surrounding the Moon.

Our Moon absorbs the solar wind which is a flow of plasma from the Sun. However, Nozomi's ISA, Ion particles (maybe, spectrum, P) analyser, detected, for the first time, the plasma which was part of the Solar wind that had been reflected by the front face of the Moon.

We examined ion velocities, Moon position, direction of the Solar wind etc in great details and as a result we found that this particular plasma was closely related to the Moon and that it had not been newly formed by the Moon and that it had rather been formed by the reflection of the Solar wind by the Moon.

It has been often said, as a result of Apollo landers, that some parts of the Lunar rocks are weakly magnetic and this seems to confirm that the shock waves formed by the Solar wind on colliding with these magnetised rocks are reflecting the Solar wind ions.

This would mean that the Solar wind is blocked at the front face of the Moon, leaving a vacuum region at the back with an extremely less plasma density. Nozomi's onboard ESA detected these electrons coming from this vacuum region.

It had been predicted that there was to be a potential difference of a few tens of Volts through the mechanism called "bipolar dispersion (best I could translate, P) between the vacuum region and the Solar wind. However, given that the reflected electrons had something like 480 eV, very high indeed, 10 times the predicted value and We may have to accept that.

(end of this chunk, P)

Posted by: pandaneko Jan 28 2012, 08:27 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


The posting just befroe this was referring to a schematic called "Electron Spectrum Alalyser/Nozomi" and that is immediately followed by another schematic, actually a chart, and there are two captions on this chart. Chracter strings in white say "Ions reflected by the front face of the Moon" and those in red say "Solar wind ions".

Here below is today's translation immediately following this chart.

I seem to have failed yet again. I cannot paste what I copied. Maybe, I shoud not have copied schematics at the same time? So, I let this go as it stands. P




Posted by: pandaneko Jan 28 2012, 08:58 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


EIS, the high energy particle counter(?), played its role as a monitor of the Solar wind at positions further away from the Earth and made contributions to the obervation of the Solar flares. In April 2002, it detected a Solar surface explosion which must have caused its own suffering from it.

(There is a chart immediately following this short text and the caption on it says "Maximum number of particles ever measued by Nozomi on 21 April 2002")

Magnetic field measurement device on board Nozomi made observations on the magnetic field emitted by the Sun during its cruise phase. The Solar wind, which is a supersonic plasma wind blowing out of the Sun's surface, carries Sun's surface magnetic field with it into the interplanetary space.

It is not terribly exciting simply to be able to measure these magnetic fields. However, Nozomi's observations were made much further away from the Earth in orbit and in that respect the data obtained was very much precious.

Nozomi made these observations as it was moving further and further away from the Earth and consequently it became possible to study how the magnetic fields of the Solar wind behaves as they move further away from the Sun.

Also, it is not easily generally possible to know the velocity (or speed) of the Solar wind in the vicinity of the Sun. However, we can measure its lateral velocity when a specially dense Corona material gashes out at right angles to the line of sight as seen from the earth.

Nozomi made direct observations of these Corona related materials and consequently we were able to obtain very precious information on how an initial velocity of the Solar wind gradually changes in the interplanetary space. (This might be useful for weather forecast for ISS?, P)




Posted by: pandaneko Jan 29 2012, 09:53 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


Immediately after the paragraph I translated yesterday is a small schematic, depicting te relative position of the probe against the plobe coming out from the Sun. The caption there says "Please refer to the floowing URL for details of the co from the Sun and Nozomi waiting to observe it". (I am not translating this)

(Now, in what follows, a schematic of "Solar corona observation by phase shaking (?) detection" and this in blue.)

(On the schematic itself there are 3 character sets as follows)

1. Frequency changes (f down= 11/3X f up)

2. transmission wave , S band (2.3 GHz)

3. Reception wave, X band (8.4 GHz)

(There are 2 rectangular blocks underneath these S and X bands and they are: )

(S band transmission) generated by a highly stable (10 to the power of minus 15) hydrogen maser

(X band transmission) reflecting the changes in the refractive index over the outgoing and incoming (inbound) routes

The antenna at the bottom is the Usuda antenna.

Next, immediately following all above is a chart called "Phase change (?) spectrum". The vertical axis is "Phase change power (rad 2/ Hz)" and the horizontal is "frequency change (Hz)". There are 4 character sets on this chart, going clockwise and they are:

1. 12 to 37 Solar radii until the Solar surface (6 to 28 December 2000)

2. Kormograph side (unsure about this translation, must be somebody's name)

3. when very far from the Sun (June 2000)

4. comparative correction signal

Just underneath all these and in pale blue is "space scale (300km/s assumed)"

Perhaps, end of part 3 of this part 4 series, P




Posted by: pandaneko Jan 30 2012, 09:09 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


What follows is a short paragraph immediately after the Phase change spectrum and immediately before the start of part 3 of this part 4 series.

As I think of all those people all over the world who had sacrificed their lives and designed instruments on board which were never used despite being so close to the Mars I feel so frustrated and sad to the extent of feeling like crying.

Nozomi had a formidable assembly of first rate magnetic and plasma observation means on board. Nozomi was to have played a significant auxilliary role side by side with European and US observers currently going there. My heart is bleeding for my colleagues.

Towards the end of the operationn there came in a flood of mails and telephone calls from all over the world, all encouraging us for then and the future. Here, I only simply aplogize for the fact that we were not able to comply with their aspirations.

Needless to say that our Nozomi team will never ever forget the fervent encouragement given to us by our colleagues and friends worldwide during the last minute death battle in December 2003.

(This is the end of the part 3 of this part 4 series, P)

Posted by: pandaneko Jan 31 2012, 10:19 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


I have had a look again at what I undertook in terms of translation re Nozomi. Part 4, the last part of the ISAS newsletter 4 part series, happens to be all about 15 instruments on board. I was in two minds as to whether I should translate them.

The biggest reason, of course, is that it now seems silly and useless to translate what all these instruments may have performed simply because the whole thing blew up (excuse me here because I had had only a very quick glance at that time when I undertook to translate this 4 part series and I was not aware exactly what the last part of this series contained!).

However, having translated the main text of this series and finding myself being in full sympathy with the author, I will continue to finish translating what remains in the series. It is only a few evenings work! This will come after my translation of another ISAS newsletter for this evening which effectively contains an ISAS version of Nozomi failure press release, as follows.

Nozomi made swing-bys by the Moon on 24 August and 8 December 1998. On 20 December Nozomi made another swing-by with the Earth at a distance of 1000 km, but Nozomi developped an insufficient propulsion due to the the mulfunction of its thruster valve.

Flight course was corrected, but this led to an over-use of the fuel and it became impossible to insert Nozomi into the Mars transfer orbit. For that reason, the arrival timing was delayed from October 1999 to January 2004.

Nozomi was placed into an orbit, after the Earth swing-bys in December 2002 and June 2003, which would have directed Nozomi towards Mars. However, Nozomi developped another mulfunction with the comms. and thermal control system in April 2003 and franctic efforts on the ground could not recover these difficulties.

A command was sent out on 9 December to change its orbit in order to ensure that Nozomi would not collide with Mars for fear of contamination of the planet in accordance with an international agreenment.

P


Posted by: pandaneko Feb 1 2012, 09:59 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


What follows and will follow, for the next few days, I think, is the information contained in the last part (part 4) of ISAS newsletter.


(reference materials)

There were 15 instruments for scientiffic observation on board Nozomi.

[Those instrument which conducted observations during Nozomi's cruising phase]

1.MIC(Mars Imaging Camera )


[Kobe U・ISAS/JAXA・Tokyo U・Kyoto Gakuen U・Kyoto U・Kyushu Tokai U・CNRS]

Result:First time observation by Japan of the other side of the Moon etc

This is a camera for visible region of the spectrum. Nozomi's orbit was to be very eccentric and it was to have travelled in the reverse direction, meaning that it would have captured the whole Mars image constantly. MIC is capable of looking at the global changes in the Mars atmosphere.

For example, these include:

growth of dust storms, transparency changes in the atmosphere due to dusts and hues in the atmosphere, cloud characteristic changes, changes in the polar region appearance, and the mists and their growth as they occur in the polar regions and others.

In addition, according to the original flight plan, Nozomi was to have a few occasions of close encounter with Phobos and Dymos.。

2.UVS(Ultraviolet Imaging Spectrometer)

[Tohoku U, National Polar Research Institute, Hokkaido U]

Result: Observation of interstellar winds outside our Solar system and others

This instrument was to have a look into the spectrum between 115 nm and 310 nm, specifically, hydrogen and oxygen coronas around Mars, daytime atmospheric lights such as carbon monoxide in the Cameron band (unsure, P) and also the measurement of D/H ratio (deuterium and hydrogen atoms ratio) which might enable us to study the evolution and the process of escaping Martian atmosphere.


3.XUV(Extra Ultraviolet Scanner)

[Nagoya U・ISAS/JAXA・Tokyo U・Rikkyo U・Communications Research Laboratory・Boston U]

Result: Imaging of the Earth plasma region and others

By looking into the Sun light scattered in the extreme ultraviolet region of the spectrum by neutral helium gas and helium ions we can study the distribution and the amount of helium gas and helium ions inthe Martian ionosphere.

Studies of neutral helium gas, for instance, will tell us about the activities inside Mars, such as volcanic activities and water circulation. Helium ion measurments will tell us how these ions came about in the first place and how they are excaping from the ionospher of Mars.


(I will continue with the rest tommorrow on, P)

Posted by: pandaneko Feb 2 2012, 09:42 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


continuing from yesterday,

4.MDC(Mars Dust Counter)


[Munich Inst of Tech, Tokyo U, ISAS/JAXA・LFM・MPIK・STMS, Kobe U, Dokkyo U, ESA]

Result: detection of interstellar dusts and others

This instrument would have measured both the velocity (1 km/s to 70 km/s) and the mass ( 10km/s dusts at 5×10-15~10-10 g ). Direct measurement of plasma's electronic charge changes due to high speed collision of dusts. Also, comparison with reference data for velocity and mass information.

The utmost objective was detection of Mars dust rings. It has been predicted that these rings were ring-like with Phobos, and torus-like with Dymos in distribution. MDC was supposed to look into this issue and offer information of these dusts distributions.

Nozomi had been detecting other dusts on way to Mars such as those coming from asteroids and comments, also those coming from outside our Solar system. The number was more than 40 by the end of 1999.


5.EIS(Electron and Ion Spectrometer)


[Tamagawa U, Waseda U, Rikkyo U, ISAS/JAXA, Tokyo Inst of Tech,MPIA]

Result: Solar flare observation and others


This instrument was to measure the enegy flux of high energy particles such as electrons, protons, helium ions, oxygeon ions etc over the range of 40 KeV to 500 KeV. Interaction between the solar winds and the uper atmosphere of Mars produces high energy electrons and ions (a few hundred eV to a few tens of KeV) and EIS was to look at these particles with a view to understanding the mechanisms for acceleration.


6.ESA(Electron Spectrum Analyzer)


[Kyoto U, ISA/JAXA, Rikkyo U, Tokyo U, Comms. Res. Lab, Tokyo Inst of Tech]

Result: observation of Lunar wakes

Electron energy flux was to have been measued (12 eV to 16 KeV). This would have given us a lot of information on the structure of magnetosphere and ionosphere of Mars and also the interaction between particle accerleration and wave/particle mutual interaction processes.

P

Posted by: pandaneko Feb 3 2012, 09:44 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


Continuing from yesterday as follows:


7.ISA(Ion Spectrum Analyzer)


[ISAS/JAXA・kyoto U・Rikkyo U・ Tokyo U, Comms. Res. Lab, Tokyo Inst of Tech]

Result: Obervation of interstellar dusts and others

This was to measure ion energy flux/charge between 10 eV and 16 KeV. These measurements would have given us an insight into the mutual interaction between particle acceleration and wavelets and partilces, in addition to precious information on the structure of magnetosphere and ionosphere around Mars just as those by ESA.


8.IMI(Ion Mass Imager)


[IRF・Rikkyo U・ISAS/JAXA]

Result: Long term monitoring of Solar winds and others

This was a light weight instrument designed to measure mass composition of ions. It was to measure ions with energy between 10eV and 35 KeV per electronic charge. It had a 360 degrees of viewangle and was capable of measuring 3D distribution of ions by making use of the probe's spin.

It would have helped to look into the interaction between the Solar winds and the upper atmosphere of Mars. IMI also had a very wide range of mass covergage and may have spotted the dust ring around Mars by its measurement of plasma composition including dusts.


9.MGF(Magnetic Field Measurement)


[ISAS/JAXA・Nagoya U STE Lab・Okayama U・Tokai U・NASA/GSFC]

Result: Long term monitoring of Solar winds and others

This was an instrument for measuring magnetosphere around Mars. We do not know yet much about Martian magnetic activities.

A US probe, Mars Global Surveyor, recently discovered that Mars had a sporadic places of very strong local magnetic activities and there was no global distribution of magnetism around Mars.

This also might have been one of Nozomi's achievements. However, the fact that within the dayside of Mars the pressure of Solar wind induced plasma and the atmospheric pressure of Mars are balanced out and co-exisiting may still have a lot for space for arguments.

Nozomi was to have contributed towards this argument as it was to fly over at a very low altitude in the Martian atmosphere.


10. Radio astronomy


[ISAS/JAXA]

Result: Observation of Corona structutr of the Sun and others

(This is to continue, P)


Posted by: pandaneko Feb 5 2012, 09:07 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".



Those instruments which were to have started observation once in Martian orbit. (I know that this is silly by now, but I am paying tribute in my own way to those who must have given us information)

1.PWS(Plasma Waves and Sounder)


[Tohoku U, Fukui Inst of Tech, Comms. Res. Lab, Toyama Pre. U, Nat. Polar. Res. Inst, ISAS/JAXA]

A method called "Topside sounder" would have looked into the range bet. 20KHz and 7MHz of the Martian ionospehre structure. At the same time, it would have examined the characteristics of the plasma in relation to the interaction between particles and wavelets. These interactions are the origins of the microscopic processes governing the direct interaction between the ionospheric plasma and the Solar wind induced plasma.


2.LFA(Low Frequency Plasma Wave Analyzer)


[Kyoto U RASC, Toyoma Pref. U, Osaka Inst of Tech, Kanazawa U, Kyoto U of Industry, ISAS/JAXA, Comms. Res. Lab, JAXA HQ]

This was meant to look into the plasma waves of Mars. LFA was to look into the wave profiles (0 Hz to 1 KHz) and the low frequency spectrum ( 10 Hz to 32 KHz). Its scientific objective was to look into the microscopic phenomenon caused by the interaction between the Solar winds and the Phobos, boundary region between the Solar winds and the Ionosphere, and the macroscopic plasma environment.


3.PET(Probe for Electron Temperature)


[ISAS/JAXA, Comms. Res. Lab, Gunma U, Nagoya U Ist of STE, Michigan U, MPIA, Korean Inst of Space]

This would have measued the electron temp. in the Martian ionosphere. One of tis objectives was to portray the thermal structure of the Martian ionosphere by continucously measuring the electron temp.

(only 2 more entries to translate!, P)

Posted by: pandaneko Feb 6 2012, 09:54 AM

QUOTE (pandaneko @ Jan 19 2012, 05:28 PM) *
What follows is the URL of the ISAS pages I am about to ranslate for some time to come.

http://www.isas.jaxa.jp/j/enterp/missions/nozomi/status_01.shtml

Its rough title is something like "what Nozomi may have left for the success of future international planetary missions".


4.NMS(Neutral Mass Spectrometer)


[NASA/GSFC, Michigan U, Graz U (unsure about spelling, P), Michigan U, Arizona U, ISAS/JAXA, Tokyo U, HAwaii U, and other]

This was an analyser which would have examined the interaction betweeen the composition of the Maritian neutral particles and the density. It would have measured the neutral gas with mass number between 1 and 60 and with the density range between
2×104~1012cm-3.

5.TPA(Thermal Plasma Analyzer)

Calgary U, ISAS/JAXA・NRC・CSA, Victoria U, Comms.Res.Lab, Western Ontario U, Alberta U, Nagoya U STE Res. Lab,. Hokkaido U

(This is effectively the end of my translation session. I am prepared to contribute more if asked, particularly in relation to my ealier postings. P.)

Posted by: Astro0 Feb 6 2012, 11:23 AM

I think that all of UMSF owes you an enormous debt of thanks for the work you have done in translating all of these documents.

Thank you Pandaneko. You are worth your weight in gold!! smile.gif

Posted by: Paolo Feb 6 2012, 12:57 PM

Pandaneko probably knows but maybe other group members don't, that there is also a Japanese book on the history of Nozomi. See http://smatsu.air-nifty.com/lbyd/2005/05/523_5e8b.html I have a copy of it, although I can't read Japanese.
Of course I am not suggesting that you may translate it for the forum... wink.gif


Posted by: pandaneko Feb 6 2012, 01:59 PM

QUOTE (Paolo @ Feb 6 2012, 09:57 PM) *
Pandaneko probably knows but maybe other group members don't, that there is also a Japanese book on the history of Nozomi. See http://smatsu.air-nifty.com/lbyd/2005/05/523_5e8b.html I have a copy of it, although I can't read Japanese.
Of course I am not suggesting that you may translate it for the forum... wink.gif


No, Paolo, thanks, anyway. No, I did not know that such a book existed. A quick look at its introduction suggests that it is a substantial work. I do not intend to eat into his time as he lives on it as a professional writer. It describes 12 years of Nozomi's life.

Looking back on Nozomi, my association with it started like this. I was walking about on a theatre stage one day many years ago and somebody, a newspaper colleague of mine who had, theoretically at least, shared a vested interest in the fate of Nozomi and the Beagle 2, shouted at me with the news, saying that there was no nozomi for the Nozomi.

That was a bad pan (nozomi is hope, Kibo with ISS is also nozomi, but in japanised Chinese) and I hated him for that.

I have been wanting to know why ever since. The Forum has given me an incentive to dig into the history and I am most grateful for that.

P


Posted by: pandaneko Feb 14 2012, 09:13 AM

QUOTE (pandaneko @ Jan 31 2012, 07:19 PM) *
A command was sent out on 9 December to change its orbit in order to ensure that Nozomi would not collide with Mars for fear of contamination of the planet in accordance with an international agreenment.

P


I have been thinking about this, for quite some time by now. I suppose that eventually, the energy density inside and at the ever thinning wavefront (emotionally...) far and far out there means that even getting feeble radio waves does not mean anything signally meaningful and useful.

OK, relay satellites, but then, after all those things, we will still be looking like goldfish contained and trapped in a glass bottle placed in this universe even if we still want to interact with the rest of this world?

If so, what then might we do?

P

Posted by: pandaneko Mar 10 2012, 08:26 AM

I was not exactly sure where I should place this posting. It is an extremely short summary (my summary) of a newspaper artcicle that appeared in Nihon Keizai Shimbun (a Japanese newspaper specialising in financial matters) here and its time stamp is 2012.3.6.2:06, meaning 02:06 on 6 March 2012.

Its URL: http://www.nikkei.com/news/headline/article/g=96958A9C93819595E2E1E2E2E08DE2E7E2E1E0E2E3E09C9CEAE2E2E2

The jist of what it says is that in around 2018 JAXA may launch a probe which will sample dusts at around 40 km height over Mars to bring them back. A 10 man team has been set up to look into the techinical details. It does mention Nozomi's failure and NASA's probe going there at the moment.

Pandaneko

Posted by: Paolo Mar 10 2012, 09:16 AM

thanks for the info. there was a similar proposal one decade ago by the Arizona State University for the first Mars Scout competition (eventually won by Phoenix)
http://mars.jpl.nasa.gov/news/index.cfm?FuseAction=ShowNews&NewsID=443

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