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Spirit rover’s first dash for freedom is a short one

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Spirit rover on MarsA NASA rover mired in soft soil on Mars made its first escape attempt in months Tuesday, but the maneuver lasted less than a second before safety precautions shut it down.

The Spirit rover, which like its more mobile twin Opportunity was delivered to the Red Planet in 2004, has been stationary since May as mission managers sought to devise a plan to extricate it from a patch of rocks and loose soil known as Troy. Even with months of testing in a laboratory "sandbox" simulating Mars’s terrain, NASA was unable to hatch a foolproof plan to free the rover, and mission leaders cautioned in a news conference last week that Spirit may be forced to live out the end of its mission in Troy.

According to an update from NASA’s Jet Propulsion Laboratory, where the Mars Exploration Rover program is based, Spirit’s first move on Tuesday was quashed quickly when the rover exceeded its preset tilt limit for the maneuver. Analysis of the data is ongoing, the lab said, and plans for a second extrication attempt will not be solidified until Wednesday or later.

The process of extricating Spirit from Troy could take months to complete, if it’s possible at all, and mission managers said last week that no official progress review would be conducted until February.

Artist’s impression of Mars rover: NASA/JPL-Caltech

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  1. 1. sparcboy 10:16 am 11/19/2009

    Just looking at the "tires" tread on this vehicle, it’s obvious those who designed it did not consult desert off-roaders. Had they, the rover would be merrily going about it’s business.

    How could you miss something so obvious? Did they not test the rover in a sandbox? I would hate to be one of those guys right now, they must be feeling like complete idiots.

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  2. 2. jack.123 4:10 pm 11/19/2009

    Those idiots as you call them,produced a vehicle that made it to Mars,and has lasted years longer than its stated mission.I doubt that desert off-roaders could have done as well even in their wildest dreams.Its more likely that their air inflated tires would have went flat just seconds after landing.What a mission that would have been.

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  3. 3. nfiertel 5:33 pm 11/19/2009

    Yes…the wheels had to be made small due to the restrictions in the launch vehicle. Considering that the mars rovers were expected to work for 90 days I would say that they have somewhat exceeded their warrantee and then some. It is possible that the rover will get out of its sand trap and one would hope so but five years is an amazing journey all right and I congratulate the brilliant team that made it happen.

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  4. 4. TTLG 8:59 pm 11/19/2009

    While sparcboy’s comment was undiplomatic (to say the least), I think it is worth considering. He seems to be saying that the tread depth on the tires (not the tire size) is far smaller that that normally used for sandy conditions. Since the move failure was due to tilt rather than not moving, I would guess that the problem is an obstruction rather than the tires not moving the vehicle. But what I think is interesting about the observation is that there is this one aspect of the design seems to contradict the practical experience from an enormous number of people. While these people are not scientists with a bunch of degrees, the tires they use are the results of what amounts to a large amount of scientific-method trial and error experimentation. If the experiments done by the rover designers created a design that was much less conservative than indicated by off-roader experience, then I wonder if the rover designers may have missed something.

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  5. 5. Voltaic 12:28 am 11/20/2009

    Hey there, TTLG, nice save. I agree that a lot of "Redneck Fourwheelers" probably weren’t consulted about the design. T&E Research on the planet Earth is certainly safer (and cheaper) than on Mars and NASA may have benefited with the consult. And yes, there’s a lot of embarrassed engineers right now. Perhaps an arm to position the drive wheels would have been handy, but then, did the budget allow for that? They had the answer…they just couldn’t afford to implement it.

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  6. 6. m1rv9n41v5 9:07 am 11/20/2009

    I think also that, they are rushing when they made a plan for making the wheel of the rover. I would rather suggest that, they should build a a compact and a folded wheel for the rover, for astronauts to easy to handle it.
    In times of lift off to the space and in assembling it to the other parts for the mission.

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  7. 7. Michael Hanlon 9:15 pm 12/2/2009

    This is a late entry into the discussion, but I noted that the article claimed "safety circuits" kicked in. Um, on a robot that has far exceeded it’s expected life use, why is anyone worried about safety in a rescue attempt?Anthropomorphically, if I were the rover, I wouldn’t want some computer calculation to halt the effort at my rescue after only one second. Let the damn wheels spin in side opposite sequence and spin the thing out of the sand. Spinning should cause the whole body to "float" above the entrapping sand. Is that computer there or here? Or at CERN?

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  8. 8. Michael Hanlon 9:22 pm 12/2/2009

    I know this is a late entry into this discussion, but I noticed the article claimed a computer calculated and activated a "safety circuit". On a device which has far exceeded its expected life , why are we worried about safety in a rescue attempt?
    Anthropomorphically, if I were the robot, I would want the rescue effort to continue past PC Calc’d safety triggers. I say, turn the wheels on each side in opposite directions and allow the device to "spin-float" its way off the entrapping sand.
    Where is that computer doing the calculations located? There? Here? Or at CERN?

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