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Unread 14-04-2011, 15:01
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Ether Ether is offline
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Re: Minibot climb rate


Given:

0.5 inch diameter wheel

0.09 Nm stall torque

0.4 coefficient of friction between pole and wheel (estimated, YMMV)


Find: required normal force to prevent slipping


Solution:


1) calculate the motive force at the wheel/pole interface produced by stall torque:

(0.09 Nm)/[(0.5/2 inches)*(0.0254 meters/inch)] = 14.17 Newtons = 3.19 lbs


2) divide the motive force by the coefficient of friction:

(3.19 lbs)/(0.4) = 8 pounds normal force required for no wheel slip


Edit:

To be clear, the above calculation is for the normal force on ONE wheel (shaft) powered by ONE motor.

If the wheel (shaft) is powered by two motors, then the number would double.



Last edited by Ether : 14-04-2011 at 17:01.