^ thanks
Here are a few links that might give you a better idea of what it is.
Here is a link that shows the drive module, this picture shows it still inside the robot. One module consists of the omnie wheel and its gearbox.
http://www.circuitrunners.com/invent..._1002_omni.jpg
Here is a picture of the overall robot.
http://www.circuitrunners.com/invent...1002_front.jpg
The piston running down the middle of the robot pushes down on that piece it is connected to which is connected to all of the drive modules which causes the modules to pop out. We could move them in and out quickly.
I hope that clarifies it a little better.