pic: Omni Design Trial

[MrForbes]

Originally Posted by JamesBrown

I was under the impression that the rollers were moving sideways but since the forces for the left side were equal in magnitude but opposite in direction they resulted in no net force (except forward).

There is an opposing sideways force on the rollers on both sides of the robot, but since they are constrained by the forward direction of the robot, they cannot roll sideways, so they can't roll at all.