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Unread 28-02-2011, 15:37
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Re: Minibot wheel slip

Quote:
Originally Posted by boomergeek View Post
From a physics POV, doesn't the formula need a component for the desired acceleration rate up the pole?

"Peeling out" would be reduced by greater normal force.
Faster accelerating minibots benefit from greater normal force. There is a balance needed to minimize normal force for gearing friction and maximizing normal force to minimize peeling out in the drag race. Maximizing coefficient of friction is always a good target.
I agree, you could set the normal force, N, solely based upon acceleration requirement rather than no_slip.

My simulations have shown that the no_slip condition is not the optimum. After the initial acceleration to steady state speed, the extra drag caused by the high no_slip N causes an unwanted power loss. There is an optimum N that balances the acceleration and steady climb phase ... and for our robots it lies between 1.8 and 2.0 * weight.