[Al Skierkiewicz]

David,
We have used a hollow, vertical shaft that is the turning point of our crab drive. The motor is mounted inside the module and the wiring passes up through the hollow shaft. With a loop above the module, 400 degrees will not damage the wire. I can't tell you anything about the programming but we have used +/-200 degrees in the past with this arrangement. BTW, our design has allowed the crab modules to be removed for service or replacement without tearing apart the robot. The module (motor, transmission, housing and bottom bearing) mounts to a rotating plate that is part of the upper bearing assy and vertical shaft. The upper bearing contains a surface for normal loading and a thrust surface for carrying the weight of the robot. Four screws and a quick disconnect of the power and any sensors and the module is out. A complete replacement can be made in two or three minutes.