Encoders on mecanum drive?

[gpetilli]

Originally Posted by Ether

The context of this thread is mecanum, which has 3 degrees of freedom.

How do you intend to process 2 encoder signals to detect those 3 motions? (forward, strafe, rotate)?

Last year's robot used two omni-wheels plus a compass. We had lots of reliability issues with the compass due to interference from the CIM motors (solved with 4ft distance), and a mounting screw which was evidently magnetized. This year we intend to replace the compass (and gyro) with a second pair of instrumented follower wheels. The two X and two Y wheels will be located one in each of the four corners. A side benefit of this approach is that we can calculate the rotation about a point near the center of the robot without locating the rotational sensor in the center of the robot (middle of a tote).