Breaks Observed in Rover Wheel Treads

Re:Breaks Observed in Rover Wheel Treads by overcast on Wednesday March 22, 2017 @09:21AM (#13930650)

I understand that, which is why I said it never seemed strong enough to begin with. I get you need to conserve weight, but doing so on the wheels, seems, crazy? The most important thing of an entire car is the tires. Without good tires, a race car can't do anything, no matter how well engineered the rest of it is.

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Re:Breaks Observed in Rover Wheel Treads by Klathmon on Wednesday March 22, 2017 @09:26AM (#13930674)

I think it's a gamble. If they made them thick enough to never break, they could have blown the whole weight budget. But if they make them too thin, the whole project is a waste.

I mean the wheels are probably among the heaviest single "things" on the rover, so adding even a small amount of thickness will really increase the weight, and that would mean cutting other things.

It's a tough call, and I'm sure as hell glad I wasn't the one that had to make it, but I think all things consitered they did a good job! It's been running for 5 years and even though these look bad, apparently it still has a lot of life left in it!

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Re:Breaks Observed in Rover Wheel Treads by JetDogRush on Wednesday March 22, 2017 @10:29AM (#13931164)

Surprisingly the wheels only weigh a few pounds each! (I still can't think in metric and I don't have a real number.)

They were primarily constrained by packing volume during cruise (https://mars.nasa.gov/msl/mission/spacecraft/cruiseconfig/) and then by shock loads as the securing pyrobolts blew during landing (https://youtu.be/Ki_Af_o9Q9s?t=4m14s).

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Re:Breaks Observed in Rover Wheel Treads by Cyph0n on Wednesday March 22, 2017 @10:37AM (#13931262)

I'm curious how you came to the conclusion that the wheels are the most important part of the rover.

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Re:Breaks Observed in Rover Wheel Treads by overcast on Wednesday March 22, 2017 @11:10AM (#13931533)

Without wheels, the rover can not rove. Pretty much makes it useless if the wheels are broke, correct? Just like any vehicle, the wheel/tire is the most important piece regarding performance. Without good contact, all that fancy machinery won't do a thing.

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Re:Breaks Observed in Rover Wheel Treads by Cyph0n on Wednesday March 22, 2017 @11:41AM (#13931783)

Definitely, but couldn't you argue the same about other important components? For example, without an engine/motor, even the fanciest wheels will get you nowhere. I think it's somewhat of a paradoxical argument.

So the way I see it is that all of the major components are equally important, but you want to optimize your overall design to be both light and reliable.

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Re:Breaks Observed in Rover Wheel Treads by overcast on Wednesday March 22, 2017 @04:55PM (#13934858)

Of course you could, that's why you don't skimp on those things. You can get by with a crappy interior, but things like wheels/tires/transmission/engine are high priority. That's my whole point here, it doesn't look like the wheels were over engineered enough, but I'm not a rocket scientist.

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Re:Breaks Observed in Rover Wheel Treads by Cyph0n on Wednesday March 22, 2017 @05:10PM (#13934998)

That wasn't clear from your original comment though. In case of the rover, other important things include comms/nav, movement controller, power source, and sensors.

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