[pras870]

The easiest way to have a pneumatic cylinder stay in position after your robot has it's power turned off, is to use the double selenoid valve. If you notice that you have a leak in your system, the easiest way i found to find a leak, is to take a cup of soapy water with a painting brush and go over all the connectors in the system. Turn the system on, if you see a bubble appear, you have a leak in that particular valve. Take the connection off, put some more teflon tape, tighten the connection enough, and re-check. We had this problem last year and this solution solved everything.