I wanted to make sure that everyone interested sees Adrian Brown's articles at http://www.thespacereview.com/article/1319/1 and http://www.thespacereview.com/article/1318/1 about the technical and budgetary problems with MSL that led to the launch slip. While I can't claim to be privy to the budgetary and political issues at the mission level, the technical discussion seems like a fair summary of the situation as I understand it, at least as good a one as can be gathered from public sources.
People in other forums have complained about errors in these articles, but without giving specific examples or providing any factual basis for their objections. I don't find that very useful. If there are real flaws in this account, I'd be quite interested to know what they are.
p.s. I guess we need to change the name of this subforum.
Thanks for linking to these Mike - they're very good, and quite thorough. What has this done to the Mastcam delivery date? I'm going to make the bold assumption that there's not a chance in hell of the zoom being reinstated.
And that's a good point about the sub-forum name Phoenix needs to get stuffed into past missions as well.
Yeah -- I've been meaning to ask when Phoenix was going to move to Past Missions, but figured that ever-optimistic Doug was waiting to make sure that Lazarus Mode failed before taking that step...
-the other Doug
I was thinking (and still think) that it would be a good idea to wait until after LPSC, the first major conference at which properly digested results will be presented. I figure it will receive a flurry of activity. Then move it.
I had also seen the Adrian Brown essays. In his references, he links to a series of presentations made about MSL on Jan. 9, 2009. These powerpoints contain the things he mentioned and more, in quite a bit of detail. They are at:
www.lpi.usra.edu/pss/jan92009
Forgive me if I lose patience with armchair engineers.
At any rate, the fixed-focal-length but adjustable focus Mastcams, like MAHLI, are mechanically very similar to the original zoom design, they just have one fewer motor and one fewer cam. From http://www.msss.com/press_releases/mahli_delivery/index.html:
"MAHLI focus is controlled by a precision mechanism developed by Alliance Spacesystems. This mechanism uses a stepper motor to position the internal focus group by means of a cam."
We're very confident that these mechanisms are not going to "lock up".
You're forgiven. It is armchair-knee-jerk reflexive, but everybody gets the heebie-jeebies with anything mechanical after Galileo. Umbrellas and tape drives oh my.
The thing that gives me the greatest heebie-jeebies is Cassini's main engine cover, which has worked flawlessly. And not to comment on MSSS, but isn't there an outgas-contaminated camera with a locked up filter wheel wizzing towards a comet somewhere? Or am I combining two issues in my mind?
You're thinking of the Stardust Navcam. That was a major spares-cupboard raid effort ( Voyager optics and shutter ) - and I don't believe MSSS had anything to do with it.
Doug
To be clear, I did not mean to imply MSSS had something to do with it. More of a crap-happens sentiment. And we could all list crap that happens with solid state stuff, too.
"Less moving parts!?!?!" The whole rover is a moving part!
Let's face it, guys -- anything that has moving parts can fail. And a bunch of stuff without moving parts can fail, too.
There is a difference between equipment that fails because it's poorly designed and equipment that fails because it's poorly made or just because things happen that you can't prevent and wouldn't be expected to foresee.
It's not, I don't think, that anyone thinks that any given organization is incompetent at making any given piece of equipment. I think Steve is right, we tend to get more nervous about devices with more moving parts than we do about devices with less moving parts (witness the greater worries about Sterling RTGs and their moving pistons vs. the more classic thermocouple-based RTGs with no moving parts).
It is important to remember that almost all moving parts on almost every spacecraft we've ever launched have worked perfectly. My feel for it is that more spacecraft have died because of electronics failures than have died because a moving part broke or stuck. But we seem to remember and worry about the moving part failures more than about fried electronics...
-the other Doug
"In retrospect they might simply have placed a dedicated third camera with fixed telephoto capability centered between a pair of stereo wide angle cams on the mast head with rather less trouble and similar capabilities as the dual zoom system."
There are no unused MSSS camera interfaces in the MSL rover. If you want to lobby for an additional camera mention there are three unused engineering camera interfaces.
Of course, we have ChemCam as an ultra high res imager - but it's not the same as a pair of matched, zoomable, focusable Mastcams.
One question about the RTG in MSL: in front of the natural decay of plutonium, will be the amount of power available for MSL lesser with the two years delay of launch?
http://mars.jpl.nasa.gov/msl/mission/technology/power
Above website states that the"MMRTG (used on MSL) optimizes power levels over a minimum lifetime of 14 years".
And if I recall correctly, the MSL delay press conference last December stated that the RTG power loss during the two year delay would be on the order of 5%
5% is a small amount of lost, so we can hope that it will not be a seroius concerns in case of a possible extended MSL mission. Thanks for the information!
Very interesting document http://www.nasawatch.com/archives/2009/07/nasa_smd_briefi.html. Amongst other things, it looks like MSL may need a supplementary solar array.
You'll be interested in this .pdf presentation by Doug Mac Cuistion: http://images.spaceref.com/news/2009/PSS.Jun.09.Mars.pdf
Among news, they envisione adding solar panels.
And hope that these probably existence of solar panels must have their own self cleaning mechanics by applying the learned lessons from MER's experience.
Isn't it a little late in the game to figure out that the amount of power available is insufficient to power the vehicle? Assembly is supposed to start in 6 months, and they're still worried about basics of the design...
I hope there's a TV documentary crew following MSL. The travails of this vehicle will surely be fascinating to watch.
dtolman,
I think that this might be a leak news from news media since it has no further detail information about the reason. If NASA informs this, I hope it would be well covered and explained.
About this I have many questions and I am not able to know what is the real reason. It would be to too early to get well acquainted.
I think that NASA must know it perfectly whether if it is or not necessary after studying their cons and pros. The main electrical energy would be based of nuclear and the solar ones would be interpreted as an supplemental and not as critical energy. On the other hand, it would to be insufficient to supply an extra needed energy due to a new requirements, or present instruments that might need an additional not planned electrical energy needs.
An additional battery capacity would be the most sounding acceptable but up to here, it is not worth to further discuss without knowing their cons/pros.
This isn't completely true - vertically placed panels will always get some diffuse light (generally about 5-15% of direct insolation on Mars) and reflected insolation (1-2% usually, higher when local albedo is high) . And when atmospheric opacity is high (Tau>~2) there is more diffuse than direct insolation although the overall levels are down to a fraction of ideal conditions. However if all you are looking for is a small amount of extra power then covering the vertical surfaces with panels will always give you some power.
A major problem that I see with it is that the extra weight and additional power management circuitry would lead to something else being removed which would be very bad.
SpaceListener,
The main source of this seems to be an article in Nature - http://www.nature.com/news/2009/090710/full/news.2009.664.html.
I didn't see this in the summary, so it probably bears repeating. From the article (concerning cost and power overruns respectively):
mcaplinger - thanks for the clarification. It can get confusing trying to parse power supply issues when everything ends up getting called "a battery" in the media.
Also - if anyone is interested - there is related information in this presentation to the NASA Advisory Committee (courtesy naswatch/spaceref):
http://images.spaceref.com/news/2009/PSS.Jun.09.Mars.pdf
The slide of interest from the presentation:
I think MSL was just too big a leap, technology wise, from Sprirt and Oppy.
Cost and time overruns are a serious problem among NASA missions - and MSL is yet another prime example of this.
I would say that Spirit and Oppy were a much bigger leap in technology from Sojourner, over a comparable time period, yet things seemed to work out just fine for them.
Brian? Read "Roving Mars" by Steve Squyres sometime. The MERs came so close to cancellation so many times, it's almost a running joke.
Spirit and Oppy were once spoken of by Ed Weiler, who had the yea-or-nay vote on continuing with them, as things that "would look just great over at Air and Space." Unflown. Forever.
The MERs also got a major descope after the "final" design had been approved -- the Raman spectrometer was axed, something that Squyres has said all along is his greatest regret from the design and assembly phase.
So, no -- the MERs didn't have an easy path. It's almost miraculous that they even got launched. And their costs overran something fierce (I don't remember the original bid numbers vs. the eventual cost through the end of the primary mission, but it was something like a 60% to a 100% overrun.) Their development cycles were every bit as fraught with peril as MSL's has been, perhaps moreso.
-the other Doug
To be fair (and not to stray OT), major projects of ANY sort very, very rarely stay within their original budgets. It's an endemic problem with a great number of underlying causes far beyond the scope of discussion on UMSF.
Very true, Nick. Especially for revolutionary projects, like the MERs and like MSL.
It's a lot easier to plan a realistic budget for something that's basically been done before than to plan a budget for something that's *never* been done before. The latter tend to vastly underestimate the actual costs that will be incurred during the learning curve-induced episodes of redesign, rework, and retest. This is true of nearly every revolutionary project.
Evolutionary projects, like, say, the design and manufacture of the 737, tend to stay much more within their budgets since aircraft like that generally make use of tried-and-true technology and are being asked to meet performance standards that are very similar to their predecessors', in very well-understood environments. Now, had Boeing in the same timeframe decided to design the 737 as a passenger version of a flying wing (a la the B-2 bomber, et. al.), even if it used the same engines, avionics, etc. as a conventional aircraft, it would end up badly overrunning its budget and take considerably longer to deliver to market than the conventional 737 took.
-the other Doug
Often a low estimate is the only way to get a project running, everyone knows its going to cost more or take longer. Look at the Boeing Dreamliner, its way way behind the original schedule, also Airbus had major problems with the 380, just to be fair and balanced.......
I wasn't suggesting the MERs had an easy road. I just disagreed with the suggestion that MSL was too big a jump to take on. I wholeheartedly support pushing development to the limits and maybe a bit beyond. To just play it safe and stay near the status quo... well, to paraphrase an old axiom...
Those who repeat the past are doomed to regret it.
The problem is that MSL is so much larger in terms of cost in relation to the planetary exploration program. An 18% overrun for it is a lot more money than it would have been for the MERs (18 percent being randomly picked for an example). My real fear is that considering that the very real possibility that something could happen to it (anything from a launch failure to an EDL problem) could have dire consequences for the entire planetary program save perhaps the missions already in flight.
I agree Ted, but if the beast works, who knows what we'll discover? I've always basicaly the same fear/hope for every probe so I take it cool till things unfold.
Your remark could be a topic by itself to know how "we" at UMSF feel about this.
I guess another reason MSL has to be such a big vehicle is that rovers can't get the 'faster better cheaper' treatment and be broken up into smaller separate missions as happened with the payload of the failed Mars Observer. You have to bring a whole suite of instruments if you want to get a complete picture of a particular locale.
This is the kind of torturous process that leads to a machine that lives dozens of times past it's minimum requirement. (I hope.)
Right, but that means that x percent overrun is twice as much. When we are talking billions, that is significant. Nothing like an order of magnitude or something, but what I am saying is that a raw comparison of the percent overrun is a bit misleading if you don't factor in the difference in cost. Also, in the case of MER, the money funded two rovers, meaning that it was less susceptible to becoming a total loss due to rotten luck, such as a launch failure.
I agree that this will be a great mission if it succeeds. Fingers crossed.
http://news.bbc.co.uk/2/hi/science/nature/8168954.stm
"In 2018, it is likely the entry, descent and landing (EDL) of Europe's rover would be handled by the Americans, using the "skycrane" system they have designed for their big 2013 rover known as Curiosity."
I hope that the date 2013 is a mistake in print.
Hadn't seen anyone discussing the MSL status report from last month -- http://spacepolicyonline.com/pages/images/stories/PSDS%20Mars1%20Li-MSL.pdf -- as presented to the Mars panel of the decadal survey.
Ohhh Thanks for pointing that out!, I had not seen any pictures of the actual MastCam till now, looks very nice .
Yes, thx so much for digging up this info, I avidly read any update on Curiosity. The excitement on launch and landing day will be excruciating.
More problems, greater costs. This is starting to look bad.
http://spaceflightnow.com/news/n0910/20titanium/index.html
Ahh crap, how unlucky, lets hope things turn out ok.
Given the litigious nature of US law and pending court cases of those involved, several posts that someone could consider potentially libellous have been culled.
(sorry...we need a "deeply-embarrassed-'cause-I-shoulda-known-better" emoticon!)
Guess I should've added a few "if"s and "allege"s to last night's post. I always have difficulty speaking lawyereze.
As a guidance - if you have to prefix your post with "I hope this isn't sailing too close to the wind..." or " I hope this isn't over stepping the mark..."
Save us all the trouble, and just assume it IS.
AND AGAIN - more posts discussing the legal issues of the Titanium issue. Anyone who posts on the subject again will be suspended.
MSL Readiness to proceed review: http://nasawatch.com/archives/2009/11/msl-readiness-t.html
I split out some posts about delivery of components to a http://www.unmannedspaceflight.com/index.php?showtopic=6642 to be used for updates on Curiosity assembly and testing.
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