Thread: Team 1296 Mecanum Bump Test
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Unread 02-02-2012, 16:15
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AKA: Keith Buchanan
FRC #1296 (Full Metal Jackets)
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Re: Team 1296 Mecanum Bump Test
Quote:
Originally Posted by JamesCH95 View Post
Polymers as traction surfaces generally lose traction efficiency as normal force is increased. Search CD or any tire test data if you don't believe me. I would anticipate some specific traction (tractive force per unit weight) loss as you add on weight. You will have more total tractive force, but relatively more mass to move.
Why would we not believe you?

Depends on the nature of BOTH surfaces of course but I'm sure you are basically correct and we have looked at the data. If we double the mass I expect a 25% reduction in the friction coefficient for urethane rubber. So I'm thinking the effect is (at worst) linear for the small increase in weight (and probably not that bad) and the bot will push its way over the bump at full weight - we'll see soon.