Using velocity_controllers rotates entire robot

edit

Every time I command the JointVelocityController on any of the wheels using

rostopic pub -1 /bartholomew/joint1_position_controller/command std_msgs/Float64 "data: 5"

the entire robot rotates, but the axis of rotation is whatever edge is on the ground and in the direction of rotation. Think of a domino but it stands back up on its other edge and keeps going.

The problem is similar to this but the solutions mentioned there are methods I'm already using, so I'm not really sure what to do with it. The problem also differs in that the slow-motion only happens when my robot is rotating. Movement without rotation is just fine.

All relevant files (I think) can be found here. Excuse any messy files, I've been doing extensive testing and will clean them up soon after posting.

Thanks.