Run with solenoids from a spike

I found a FESTO VPLE18-M5H-4/2-1/4 pneumatics valve in our pneumatics box, its the same one we used on our 2008 robot, it is ran by a spike. We are only using one solenoid on our robot, can we still use this on our 2012 robot?

Eric,
This appears to be a legal valve and it can be powered by either the solenoid module in the Crio or a Spike. Please remember that you have to account for the cost under the BOM and all other robot rules apply.

I have a safety concern with it also, when the voltage is 0, like it is on disabled it will still put air from the system into the piston. So if the robot is turned off it will (if it was on) move the piston. The safest way should just vent all sides to the atmosphere.

Yes, that is what “stand clear” stickers are for. This is normal and (sometimes) desirable if you want the robot to continue to move after the match ends.

Eric,
When designing pneumatics one should plan that nothing moves when the robot is enabled and pressure in the pneumatic system starts to build. It is relatively easy to do this if you think about it.

We could set the default position to up, but if it is down when the round ends, it will move back up when it is disabled or powered off.

I have an idea, if I put another solenoid just off the working end that will release all the air out of the working end the robot is disabled or shut off. It would plug up the storage so we wont lose our storage between rounds or demos.
There is a rule that says we cant use multiple solenoids to run a single cylinder, do you think that they would consider that against the rules?

Eric,
Not exactly sure what you are asking. The rule about multiple solenoids on a single cylinder is to prevent higher than normal airflow into the cylinder.

Basically what I want to do, is have an extra solenoid on the robot that will release all the air on the working end of the system if the robot is disabled.

Check out the information sheet here: http://team358.org/files/pneumatic/FestoFIRST_Instructions.pdf

This is a 1 way valve, so it has a default position when it is not actively switched. So if the piston is connected to the valve as described in the operation table on that page, when the valve is not activated, the default position of the piston is with the rod retracted. You can use that to your advantage in your design - when the match is over and the robot is disabled, the rod will retract.

I think this type of behaviour is what you want. Now you need to work that into your design for use of the piston.

Sorry if I am confusing some of you it took about 15 minutes to explain to one our mentors what I wanted to do. I did find a solution to my problem though, so hopefully I can get some sleep tonight.

This setup will release all the air out of the working side of the pneumatics system while keeping the storage held if the robot is disabled, emergency stopped, or powered off.

This setup is using the FESTO VPLE18-M5H-4/2-1/4 pneumatics valve (http://team358.org/files/pneumatic/FestoFIRST_Instructions.pdf)
On the default state 1 will go to 2 and 3 will go to 4, when it is on 1 will go to 4 and 2 will go to 3. I connected 1 to the air source, 2 to a plug, 3 is open to the atmosphere, 4 is to the working end.

Eric,
From what you describe, I am not sure that there is a legal method to achieve this result. If you open the working pressure side of the regulator, you will also release all stored pressure on the robot. I would rather your robot do nothing when disabled then for it to potentially move when disabled. You will be cycling through enabled/disabled throughout the competition season. During at least one of those times, an inspector will be standing near your robot checking over systems during a “power on” test where you will be asked to enable your robot. When the systems test is complete you will be asked to disable the robot and then power down while the inspector checks other power off functions. I don’t want an inspector surprised or hurt by the sudden release of air or the movement of parts.

The way I designed the system it will bleed all the air of the working end to the atmosphere, but I also got it to not release the air from the storage end. When it bleeds all the air form the working end it will release all the air in the cylinders form the robot so it would have no compressed air in it when the robot is off.

That’s the thing though, in the process of releasing the pressure, whether it be from the High or Low(working) pressure side, chances are, parts will be moving as the cylinders lose pressure.

at least when they move they wont have 60psi behind them, they would just float.

Gravity is irrepressible!

Spring return pneumatic solenoid valves are legal. They are in the 2012 kit of parts (first choice). If they are energized when the match end (robot disables) They will return to the d energized position. The cylinder they are plumbed to will also return to its disabled position. One side of the cylinder will have pressure on it. This is legal. Don’t over think this.