Mars Rovers Update

[JohnBoucher]

Yes.. They are still going and going. New software is on it's way

http://news.bbc.co.uk/2/hi/science/nature/5022524.stm

[artdutra04]

Originally Posted by JohnBoucher

Yes.. They are still going and going. New software is on it's way

http://news.bbc.co.uk/2/hi/science/nature/5022524.stm

Now if only automobile manufacturers could make cars as long-lasting as the MER.

Spirit and Opportunity are just incredible pieces of engineering, lasting 855 and 834 days respectively on Mars, and still going. And to think that their designed lifespan was only 90 days. That is just incredible. When we return to Mars in the future, I think we should find the two rovers and retrieve them back to Earth, so that the real rovers can be put in the Smithsonian. They certainly deserve it. (Then again, by the time we return to Mars the two rovers might still be exploring. )

And to think that 2/3 of all missions to Mars fail, this only makes it seem even more impressive. Kudos to everyone at NASA for this mission!

[DonRotolo]

Originally Posted by artdutra04

Now if only automobile manufacturers could make cars as long-lasting as the MER.

Kudos to everyone at NASA for this mission!

Although I agree that the rovers are a fantastic achievement, give me their budget and I will happily assembly you a car that will function for 900 days, or even triple that. You do need to limit speed to a few MPH, distance per day to a few dozens of meters, no moving traffic nearer than a hemisphere.... I'll even throw in the low temperature and solar-powered package, no extra charge !

The point is, everything is a compromise. For a million dollars, we can build a very reliable Ford Fiesta - but would you buy it? What if we sold a car for $800 - but it always needed repairs frequently (like, once a mile or more) - would you buy that? Between those two extremes lies "what the market accepts" - which is (hopefully) close to what you've built.

This is the basic essence of Engineering: Getting more for less.

Don

[Billfred]

Originally Posted by Don Rotolo

Although I agree that the rovers are a fansastic achievement, give me their budget and I will happily assembly you a car that will function for 900 days, or even triple that. You do need to limit speed to a few MPH, distance per day to a few dozens of meters, no moving traffic nearer than a hemisphere.... I'll even throw in the low telperature and solar-powered package, no extra charge !

The point is, everything is a compromise. For a million dollars, we can build a very reliable Ford Fiesta - but would you buy it? What if we sold a car for $800 - but it always needed repairs frequently (like, once a mile or more) - would you buy that? Between those two extremes lies "what the market accepts" - which is (hopefully) close to what you've built.

This is the basic essence of Engineering: Getting more for less.

Don

"You must spread some Reputation around before giving it to Don Rotolo again." Drat!

But to get back to the topic, the software seems interesting. I always enjoy reading how groups take their past learning experiences, both good and bad, and use them to develop new applications.

[JohnBoucher]

Great article in todays NY Times science section also
http://www.nytimes.com/2006/05/30/sc...=1&oref=slogin

Watch the video. It is so cool, it could be a game hint

[Elgin Clock]

Originally Posted by Don Rotolo

This is the basic essence of Engineering: Getting more for less.
Don

I beg to differ. That's the basic essence of consumerism. The basic essence of engineering is add more features and who cares about cost.

The project manager (not the engineers) keep it in check as to how much it will cost in the long run, and if you have to sacrifice features, then marketing plays up the ones you have.

[JVN]

Originally Posted by Elgin Clock

I beg to differ. That's the basic essence of consumerism. The basic essence of engineering is add more features and who cares about cost.

The project manager (not the engineers) keep it in check as to how much it will cost in the long run, and if you have to sacrifice features, then marketing plays up the ones you have.

Ummmm... nope!
Engineers often have set budgets to work within. These budgets are a major factor which can drive design-tradeoffs.

I'm hoping from your "" that you were just joking, but I'd also like to make it clear to all the budding-young-enginerds out there that the methods outlined in your post isn't the way things work. I make decisions everyday which are driven by cost-considerations.

Striking the balance between function and cost is the challenge we all face.
We deal with these decisions each season on our robots -- weight-constraints, and size-constraints often keep me up at night during the 6-weeks. This can be just like real-life.

JV

[BrianBSL]

Originally Posted by Elgin Clock

I beg to differ. That's the basic essence of consumerism. The basic essence of engineering is add more features and who cares about cost.

The project manager (not the engineers) keep it in check as to how much it will cost in the long run, and if you have to sacrifice features, then marketing plays up the ones you have.

If I designed everything with no regard for cost, and just let the project manager shoot it down...I wouldn't have a job anymore. They honestly don't have time to deal with cutting unnecessary costs and expect you to make reasonable compromises, and only defer the large functionality changes to them. At least where I work, thats the way it is.

[KenWittlief]

Originally Posted by artdutra04

Spirit and Opportunity are just incredible pieces of engineering, lasting 855 and 834 days respectively on Mars, and still going. And to think that their designed lifespan was only 90 days.

I seem to recall that the design team fessed-up on this. The project mission was only 90 days, but they knowingly overdesigned the system so it would last much longer.

Engineering philosophy learned from Scotty!

[DUCKIE]

I figure this is the best spot to put this...

I was lucky enough (Yay for being Space Camp staff!!! & having the day off.) to get into to an early screening of the new IMAX movie "Roving Mars" yesterday. I rather liked it... (but I AM biased.) However, I think the kids will enjoy it too. It follows the building and transport of the twin rovers to Mars... then speaks/shows some of their travels.

I was hoping to see you on the big-screen Dave! as I've already caught a glimpse of you in one of the little looped movies in the museum. I think the people sitting around me in the theater got a good laugh as I must have been mumbleing "where is dave?... is that dave?....oooh ooooh?" But have no fear movie-goers there are a few good (but short) shots where you can pick out Dave in the JPL mission control durring the rover's landing on Mars.

(Just don't be looking for Dave in one of his hawaiian shirts... as he's undercover in civies.)

[DonRotolo]

Originally Posted by KenWittlief

they knowingly overdesigned the system so it would last much longer.

You know, that makes me wonder: What does everyone think is the weakest link (system) in the rovers, the one that is expected to fail first and effectively disable the robot? This would be a system that just couldn't be made more robust, (almost) regardless of cost.

I think it would be the batteries. At a certain point, there's little one can do to increase their lifespan.

I would be quite surprised if they didn't know the answer already - maybe Dave can chime in after we have a few guesses...

Don

[EDIT]: The point being, of course, for FIRST students to learn something from the exercise and do a rough & dirty MTTF evaluation of next year's underwater robot...[/EDIT]

[Billfred]

Originally Posted by Don Rotolo

You know, that makes me wonder: What does everyone think is the weakest link (system) in the rovers, the one that is expected to fail first and effectively disable the robot? This would be a system that just couldn't be made more robust, (almost) regardless of cost.

I think it would be the batteries. At a certain point, there's little one can do to increase their lifespan.

I would be quite surprised if they didn't know the answer already - maybe Dave can chime in after we have a few guesses...

Don

[EDIT]: The point being, of course, for FIRST students to learn something from the exercise and do a rough & dirty MTTF evaluation of next year's underwater robot...[/EDIT]

I'm going to take a highly unqualified guess and say that the drivetrain will be what disables the robot. Spirit's already down a wheel, and what I've read on the NASA site seems to indicate that losing it is a significant setback. (I'm picturing a FIRST robot throwing a chain, but on a grander, no-pit-areas-or-time-outs-for-you scale.)

Granted, you can still get good science from a crippled or stationary robot (as Spirit is demonstrating now while it winters over), but it certainly would put the brakes on searching for any other points of interest.

[dlavery]

Originally Posted by JohnBoucher

Yes.. They are still going and going. New software is on it's way
http://news.bbc.co.uk/2/hi/science/nature/5022524.stm

Unfortunately, this article is a little premature. The formal decision has not yet been made to upload the described software to the rovers. We will not be having the final software review and readiness evaluations until the middle of June.



That aside, the rovers contine trundling along. Well, almost. Spirit is basically parking in her current location for the rest of the Martian winter, so that she can maintain a power-positive condition during the periods of low solar illumination during the winter over. Opportunity is digging her way out of another little sand trap. Once her wheels are clear of the soft soil, she should be ready to continue her journey south towards Victoria Crater. Victoria is nearly eight times the diameter of Endurance Crater, where Opportunity spent nearly six months exploring during 2005. We expect to get there some time in August. At that point, we are likely to see some of the most spectacular scenes yet returned by the rovers.



-dave