Releasing Pressure

[GGCO]

ok, we have our pneumatic cylinder in our robot using the standard FESTO valve set up as a two stage device. When the piston is out it latches a rod that is pulled back by surgical tubing. What I'm wondering is how we would release this cylinder at the end of the match because if we leave it out we have a lot of stored up energy but theres no way to retract the cylinder after the match ends because it is wired up as a two stage cylinder without an automatic return when power is removed. We have come up with 2 ideas for this to work.

1) have it finish the match with piston out and energy stored up and have a "lock" make sure our kicker doesn't fire.
2) have a small circuit that when power is removed it uses stored up energy in a capacitor to fire the other side to release it.

in my opinion BOTH methods are not valid because in option 1 we have a lot of energy stored in the bot at the end and if i am correct all this energy needs to be released at end of match. and option 2 seems illegal as well because we are triggering electrical components to move AFTER the robot is disabled. Idea 2 may not be "illegal" but in my opinion judges would see this as a MAJOR safety hazard on the bot.

Long and short of it.....i need to get an official ruling on this or have any other ideas suggested on this topic. Thank You.

[Carter12s]

All you need to do is set your program to release the piston at the end of the match.

If you are using labview
Open the Finish.vi File and add a reference to the solenoids necessary to release the piston. Connect the reference to solenoid set.vi with constant values. This should accomplish what you need.

[GGCO]

Any ideas of how to do this in Java?

[DonRotolo]

A safety device is a good idea.

You can manually actuate solenoids with those tiny buttons on them. You can retract the cylinder that way. (But, the kicker is still loaded, right? Then see my first answer).

Or, retract the cylinder as soon as the kicker is loaded, automatically (quick out then in). That way it is never 'out' more than a second or so.

[Gary Dillard]

How about just opening the pressure release valve?