Quote:
Originally Posted by Kevin Sevcik
the maximum speed of a mecanum strafing is less than the maximum speed moving forward/backward
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This is a practical limitation, not a theoretical one. It is due to the fact that the mecanum's rollers do not spin when the vehicle is moving forward/backward*, but they do spin (very fast) when the vehicle is strafing. The friction in the roller bearings wastes energy that would otherwise go into vehicle motion. The inexpensive mecanum wheels used by most FRC teams exhibit this behavior. It is possible to design and build mecanum wheels that minimize roller bearing friction but doing so would be beyond the resources of most FRC teams.
In directions other than pure forward/reverse or strafe, there is a theoretical reduction of maximum speed (even with friction-free roller bearings). This theoretical reduction reaches a maximum of 30% in the pure diagonal direction.
*There may be some slow spinning of the rollers due to axial free play in the rollers, or under high loads (accelerating, climbing a hill, or pushing an object) when operating on a compliant surface such as soft carpet.