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Mars Rover Spirit Down a Wheel
riflemann writes "NASA is reporting that two years into its 90-day mission, Spirit has lost one wheel and is now running on five wheels, dragging the broken wheel. With this reduced mobiity, the rover still needs to make its way to a slope where it can catch enough sun over the Martian winter to keep it operating. 'Even though the rovers are well past their original design life, they still have plenty of capability to conduct outstanding science on Mars.', says project leader Dr. John Callas."
I've had worse.
I still believe both rovers will be alive
when and if Vista is ever released.
You are being MICROattacked, from various angles, in a SOFT manner.
I don't think their hardware meet Vista's specs.
Then I remember a story Spider Robinson told about a cheap digital watch that died on him. He was pretty pissed off, but then he remembered that:
a) it was originall a Crackerjack prize or some other freebie.
b) it was 5 years into it's projected one year battery life.
At this point he gave it a solemn memorial service and kept it in a revered place (I think he may have buried it).
Whenever they finally die, I hope that they find an honored place in whatever museum the future Mars colonists decide to set up.
R2.0
"As God is my witness, I thought turkeys could fly." A. Carlson
If a dog can walk on two legs you better hope this thing keeps going, otherwise it's pretty embarassing.
http://youtube.com/watch?v=OZqVvYkCe68
The NASA engineers always triumph!
I think its great that the mars rovers lasted as long as they have. when you consider the failed mars mission attempts, spirit and opportunity are huge successes that have long outlasted their expected lifespan. The new mars orbiter "MRO" is sure to provide more information about the surface of mars, and possible landing sites for even more capable landers in the future. my question to /.ers is this: should we be focusing so much on mars or should we be looking toward other possible outposts/life harboring worlds like europa. and the new horizons mission to pluto - a waste of time, or an exciting new learning opportunity?
personally, i doubt life will be found on mars. and i'm doubtfull any significant life will be found anywhere in our solar system. but, we are natural explorers who will continue to explore, even with a bum wheel.
Martian1: It broke it's leg. I say we shoot it and put it out of it's misery.
Martian2: nah. It seems to have such a drive for life.
OS Software is like love: The best way to make it grow is to give it away.
Doesn't really LOOK like it's free spinning:
1 /2F195698779EFFAQ15P1210L0M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all/2/f/78
Hmmm, typical NASA project, 21 months late and far over budget. :)
Oh well, what the hell...
A sense of triumph swept our fair red world today when reports came in that the Grand Army of the Council had damaged one of the robotic invaders from the evil blue planet. K'Breel, speaker for the Council of Elders, made the following comment:
When a journalist suggested that the terrible monstrosity had merely worn out one of its locomotive rotators, K'Breel had the traitor's gelsac mutilated immediately.
Apologies to TripMaster Monkey.
What do you expect? The rover has lasted *8* times longer than design. That's the equivalent of driving 400,00 miles on tires rated for 50,000 miles. It's a heck of an accomplishment and I can only applaud the terrific job the design engineers and builders did.
100 mile free towing too!
(My experience with brushed and brushless motors comes from R/C planes, where a brushless motor is sometimes twice as powerful and 50% more efficient than a similarly sized brushed motor. Of course, a large part of this is that the brushed motor is dirt cheap, made cheaply in every way, and the brushless motors are of higher quality, but even so, even when comparing high quality stuff (and not cheap speed 400 can motors) the brushless are signifigantly better.)
My tricycle had training wheels.
They made Spirit and Opportunity do some battlebot stuff. And well, Spirit is a puss.
It is no longer uncommon to be uncommon.
It's not that simple. The rovers are full of fairly sophisticated sensor packages, most of which can't handle the extremely low temperatures on the Martian surface. They need the batteries to basically, well, run the heater.
The principle investigator for the missions has written a book, "Roving Mars", that really is worth the read.
This little guy seems to make it on his own just fine on one leg. Although, admittedly, he'll prob'bly never take him a wife.
They stopped using the wheel about a year ago for a while because it was having problems as if the lubricant was wearing off, and it indeed did *not* free-spin when power was not sent to it. They simply dragged it around by running the rover backward. They found it easier to control the rover by dragging the bum wheel rather than by pushing it. They only used the wheel for close-up control when rocks were being targeted. Eventually it started working properly for a while, and now won't turn at all. It does not appear they have a "free spin" mode. Dragging is it.
i t01.html
I beleive they have a video about the last time the wheel was left dragging. They did some test-bed simulations of an Earthly rover copy. Page down to the "Driving Uphill Backwards" portion, about half-way down the page:
http://marsrovers.jpl.nasa.gov/gallery/video/spir
Table-ized A.I.
Hopefully at the next Pit Stop the guys that are wiping down the solar panels will also jack it up and change out the wheel.
Ten seconds! Go!
"There is more worth loving than we have strength to love." - Brian Jay Stanley
though pain it does not feel.
Now it limps along the Martian soil,
alone in a great vastness of red sand and rocks.
I hope it reaches the top of the slope,
else alas for naught will it toil.
For in that vast desert there's no telephone box.
Nor much chance for hope.
Like the injured lone explorer,
Oh! What a horror!
it will suffer its demise,
Alone on that alien world,
Its nearest neighbor far away,
as no one hears its cries.
The wrath of Mars is unfurled,
And there alone will it lay.
It is so interesting that we leave tire tracks on other planets. They may be that the first signs of life we find, or that other beings find.
Imagine the tension if we found ourselves face-to-face with a foreign martian rover!
Bingo. Indeed, it's even worse than that: if you can't run the heaters, all of the electronics undergo more extreme thermal cycling. This causes components to contract, flex, break, etc. Several critical components -- e.g., the CPU -- have no redundancy; if one of those goes, the whole rover goes.
This failure is the most dangerous thing to happen to Spirit since the flash anomaly on sol 18, when we effectively lost contact entirely for several days. Frustratingly, we're within sight of a safe haven -- only about a football field away -- but we might not be able to get there. Some people on the team think that if we have to drag a wheel, we can't climb the slopes we need to climb to make it to safety. I would just hate for Spirit to go this way; it would be like dying of thirst within sight of water, and she deserves better. (On the other hand, one thing I've learned is this: never bet against the rovers.)
Agreed! And since Steve's such a great guy, I'll linkify that. :-)
Also looks like it's coming out in paperback soon.
``Life results from the non-random survival of randomly varying replicators.'' -- Richard Dawkins
Those are very good points, but I think that most of the reason for the unexpected longevity of the mars rovers is that they expected dust from dust storms to critically hamper the solar panel operation. What was a surprise is that the wind quite effectively kept the solar panels clear of dust, giving a much longer lifetime. I don't think that the engineers expected to have to worry about the motors lasting 36 months or more since it was not expected. Mars has quite extreme temperature swings, so the engineering is probably worth what it cost to build the rovers. Mother nature is something that just can't always be anticipated, unless, of course, you anticipate problems due to mother nature. In that case, any positive turn of fate leaves you in the position of underestimating vehicle longevity.
The temperatures, radiation, dust, vibration... these are very harsh environmental variables. It is just amazing that they are still running. I'm sure that NASA is still as amazed as we are, and pleased to be continuing the scientific research at what amounts to a budget bonanza.
You are most probably right in thinking that what was learned this time around will be incorporated in the next planetary exploration vehicles, and a longer lifetime expectation will be part of that. In line with that, recent NASA un-manned missions have been incredibly successful. I look forward to more solar system exploration, and also to commercial exploration based on NASA work.
Now that we know how to build robots to explore Mars, we can build them to explore other planets, and that ion engine thing is a Trekie's dream. The expectation bar is rising, and that is a good thing. The X-prize and similar efforts are creating huge scientific 'wealth' for all to use. Its all very cool.
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Uhm, this gets informative? The Rad6000 chip runs at 20mhz according to wikipedia and 25mhz according to other sources. The chip is based on EARLY power cpu designs (think early/mid 1990s), and most definitely does NOT include any sort of altivec technology.
No radiation hardened space suitable chips are "cheap." Expect to spend tens, if not hundreds of thousands of dollars per CPU.
That's not to say it's not a great chip for what it does, but come on...