I have a great story for this. My team used a limit switch to stop the arm when it it's fully retracted (we used an extruded aluminum extending arm). so during one match I tried to retract the arm after we got back for those extra 10 points it wouldn't retract!!. we tried everything at the pits to get it to retract. we could extend it but not retract it. So we formulated a plan so we weren't totally useless to our alliance. About 20 seconds before the next match started the Driver ken Yells out to our mentor "It's the limit switch!!" so our mentor runs from the driving station to the robot and rips out one of the wires on the limit switch. then of course it worked. They blame me for it, but then again i successfully turned an electronic stop, to a mechanical stop
. so it's all good. I think you should go with the idea from Al Skierkiewicz. But another alternative is to use those sensors from house alarm systems, the kind you put on doors.
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Whats the difference between mechanical engineers and civil engineers?
Mechanical engineers build weapons, civil engineers build targets
