[Specialagentjim]

Originally Posted by BurningQuestion

Last year, our team used a telescoping arm/ winch system for our pull up arm.
We used a latch that would prevent it from back driving. The latch would engage/disengage from a notch in the winch drum whenever we wanted it not to back drive (the operator would press a button to latch the winch). It was spring loaded to pop into the notch, but we used a servo to hold it out of the way until we wanted it to go in.

-- Jaine

We did this also last year on our rack and pinion. The real nice trick that we used was it was all done through software. When we moved the arm down, it ratcheted past it. When we moved the arm up, you would press the up button as normally, but he software would delay moving the arm, and instead first release the servo. With this, the drivers would barely even realize in a match there was a servo on there at all. Minimizing functions your driver performs I've always found to be crucial (Hey, we're slow!)