Using the traction wheels for going over the ramp since we aren't confident the mecanum will be able to handle this at an angle since not all the wheels will be touching the ground, but we also want side to side movement for lining up the totes. And we would like to be able to deploy the back two traction wheels while on the ramp so we can be more level while placing the stack of totes onto the platform.
http://imgur.com/1isBsH4
If anyone was curious, these are the wheel plates we are using. 4 plates are 1/4" aluminum going on the part closest to the robot where the piston attaches, and 4 plates are 1/8" going on the outside of the wheels.