Spirit rover glitch explained.

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KennyR wrote:

Which is my way of saying that I still think the NASA rovers were over-engineered.

No, if they hadnt had the features in question we either would have had a rover get to mars without the additional features that were added or a system that couldnt have recovered from the errors as it has.   Why imply something is overengineered when it has allowed itself to be fixed from 150 million miles away.  
    -Tig

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blobrana wrote:
Hum, but simpler also means cheaper...
I think that NASAs agenda was towards having many low-cost missions, rather than a few high budget ones.

This is a low-cost mission.  

The use of `off the peg` and recycled parts must be a better solution to a cash strapped nasa.
But i suppose that this particular mission is very public and news worthy so i imaging that they did provide a lot of `redundant` features to the design...

They used the same space qualed processor card they have used lately, used the FAA qualed version of VxWorks, which they have used in the past and got to reuse lots of code, the "simpler" design would have had to be custom and would have cost more to make.   Also when this situation happened we would have lost Spirit if it was a simple system.  The US is the only country to have successful landers on Mars, we've had 5, its silly to imply we are doing it wrong, when the other countries efforts have failed.  If we lose Spirit or Opportunity tomorrow, they will still have each been a huge success, and in all likely hood we'll be hearing from them for at least the next 45 days or so.  
      -Tig

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Glaucus wrote:
@Tig,

Didn't the Soviets/Russians succesfully land probes on Mars?

  - Mike

Two close trys, lots of other misses.   Mars 3 may have transmitted for a little bit less then 20 seconds upon landing in 1971, it then was DOA, there still is a debate about whether this was an actual message or whether it was radio traffic that happens when you drop a lander too hard.  That could have been resolved if the orbiter had not lost fuel, not made its predicted orbit and crashed much earlier then expected, though there are some spectacular pictures from that craft.   Mars 6, sent about 4 minutes of data on its descent before crashing into the surface.   Due to damage caused by its spaceflight, most of the data was useless from the lander.   And thats the closest anyone but the Americans has come, thats why we were cheering for the Beagle2, the ESA would have accomplished a task the Russians had not.  
    -Tig
   

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Glaucus wrote:
Strange how the Ruskies have failed on Mars while have succeeded on Venus. What makes Mars so tricky?!?

With its orbit, its usually at least twice as far away from us then Venus, plus its twice as far from the Sun, which isnt good for solar power, and it has a thin atmosphere (compared to us or Venus soup).    
    -Tig

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KennyR wrote:
The Russians never put a man on the moon either. Actually its very surprising what they did manage to do, given that most of their GNP went on their military and nuclear arsenals.

Yeah, but that have been to the moon and brought rocks back from the moon.   Its not a technical feat they are incapable of doing, they have however killed all 8 of their Mars landers and basically all 16 Mars efforts have been pretty dismal from the USSR.  Next year we launch the Mars Reconnaissance Orbiter, which will be able to find all those crashed vehicles since it will be able to pick up items as small as a dinner plate on the surface of mars all the way from Orbit, and then in 2009 we launch the Mars Science Laboratory which theoretically will run for years on its nuclear power cells
    -Tig

             

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odin wrote:
Hm, so there's gonna be nukeplants put on a big pile of explosives? Wouldn't want to be around it when the launch fails :nervous:.

The US has done 7 I believe in the past, a challenger like explosion of the craft in question would not harm the system.  The Russians may well have done more then us, my link to that info is not operating at the moment.
     -Tig