[Joe G.]

We're using a servo with a cam to actuate a pin, which will interlock with holes drilled in one of our gearbox gears. It's based off drivetrain braking systems by team 25. A cam is a nice mechanism to use for this application, since you really don't need much travel at all, and it can be made completely backdrive resistant through strategic positioning of dwells. For a pure elevator, I agree that software solutions are probably the best, but our robot has an interesting feature which requires it to hold its position while disabled.

In 2014, we used a dog gear which interlocked with a custom made ratchet and pawl mechanism, using WCP dog shift components. It could have just as easily been done with the andymark servo shifting setup. It worked, but we weren't happy with how much force disengagement took while under load (the eventual solution was to pulse our winch forwards ever so slightly when disengaging, taking the side load off the dog gear).