Nozomi in perspective, Revisiting the causes of failure |
Nozomi in perspective, Revisiting the causes of failure |
Oct 23 2011, 09:12 AM
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Member Group: Members Posts: 817 Joined: 17-April 10 From: Kamakura, Japan Member No.: 5323 |
http://www.mext.go.jp/b_menu/shingi/uchuu/...ts/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 |
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Dec 21 2011, 11:27 AM
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Member Group: Members Posts: 817 Joined: 17-April 10 From: Kamakura, Japan Member No.: 5323 |
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 |
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