Thread: Arms
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Unread 07-04-2007, 19:42
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Re: Arms

Two motors, globe + denso on on the arm joint, along with a gas shock to counterbalance the weight of the arm. Small motor + ball screw + transmission for the wrist.

A pneumatic cylinder extends and retracts the arm (only need it extended for pickup off the floor and for scoring on the top row) and pneumatic cylinder opens and closes the gripper.

Pneumatics are great for *FAST* response or for linear motion. However, for exact and quick, I'd always go with a geared down motor on a non-back-drivable ball screw or worm screw.

PID loops are great, but if you can avoid the complicated programming with a simple mechanical solution, and you have the weight, why bother?