[PAR_WIG1350]

What if a set mecanum wheels was built that used 2 axles per roller? Since the roller can't rotate about 2 axes simultaneously, there would be no rotation, but there would still be axial free play. Then you could build a set of wheels that is mostly identical, but which uses only one axle per roller to allow rotation. By comparing the 2 wheel sets in situations where the robot strictly moves forward or backward should tell us if there is significant rotation of the rollers in these cases.