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Unread 06-05-2012, 08:25
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Ether Ether is offline
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Re: Mechanum Wheel Sizes

Quote:
Assuming 45 degree rollers, it would be 50% slower. It acts like a gear reduction.
It's not analogous to a gear reduction.

Neglecting friction, axial free play in the rollers, and compliance of the floor surface, vehicle speed in the strafing direction with 45 degree rollers is exactly the same as the forward direction, for any given wheel speed.

The reason the inexpensive mecanums used in FRC are slower in the strafing direction in actual practice for a given throttle setting is due to friction and axial free play in the roller bearings, friction in the drivetrain, compliance in the flooring (carpet), and open-loop control of speed.





Last edited by Ether : 06-05-2012 at 08:56.