If you used pneumatics to hang, would double-acting solenoids retain air in the retracted position after the match was over?
Yes
(10char)
Yes, the piston retains its default state (position when solenoid is open) when the robot is disabled. They will always be in that position if the micro-controller is on.
If you use the catapult to hang, you should have a button to have it lock and unlock after the match is over so you can retract the pistons back into the default position, have a lock mechanism… 