[Alan Anderson]

What solenoid valve are you using to control the pneumatic cylinder? If it's a "single solenoid", it will automatically disengage when the signal to extend is removed. All signals are removed when the robot is disabled.

To keep from having this happen, you need to use a "dual solenoid" which requires two control signals, one to extend the cylinder and one to retract it. That way it won't change state when the robot is disabled.