NEED HELP WITH uncontrollable pneumatics

[Tds123]

OK guys! here is the deal, here i will give u a picture of our setup.... battery to generator, to 4 tanks, to regulator, to single solonoid, to double solonoid, then to piston the piston is connected to our arm and we use the single solonoid to control how much it goes up and down, which works fine by the way , we can control it completly but thing is the arm is way to floppy i can put my finger on it and the arm will go down any suggestions??? or ideas on why this maybe happening?

[vivek16]

how big's your piston? maybe your problem is that you do not have enough pressure. at 60 psi, most pistons are pretty solid.

Does it always do that? maybe you have a leak?

wierd, Vivek

[MrForbes]

See my post in this thread

http://www.chiefdelphi.com/forums/sh...threadid=63558

Good luck! you still have a week to figure it out....if you post some pictures of the robot, we might be able to suggest some ideas.

[Gamer930]

Which double solenoid you using??
For the SMC the aluminum operating pressure is 20 PSI and the FESTO 30 PSI

What do you have the regulator set at???

I know at least with the FESTO that if you don't have a supply pressure of 30 PSI that it goes into a neutral state and the cylinder will not extend. What most teams do is regulate the exhaust off the solenoid. Check out the thread in squirrel post

[Tds123]

Originally Posted by Gamer930

Which double solenoid you using??
For the SMC the aluminum operating pressure is 20 PSI and the FESTO 30 PSI

What do you have the regulator set at???

I know at least with the FESTO that if you don't have a supply pressure of 30 PSI that it goes into a neutral state and the cylinder will not extend. What most teams do is regulate the exhaust off the solenoid. Check out the thread in squirrel post

the regulator is set at60 so i guess by the time the arm goes up it loses 20 psi , so it is at 40 psi and my finger pushes it... and thanks to everyone that posted , well worth my time of finding how to post a thread which took me 1 hour to find and please post mmore suggestions

[RyanN]

Also, remember that pneumatics works on compressed air... When you put your finger on your arm, the force you exert is greater than it was before, causing the air in the piston to compress and move down. Try using a larger diameter piston or moving your piston to the outer part of your arm.

[Kirk]

If you are trying to control the length of a cylinder you want a "center off or center closed" solenoid. Instead of the spool inside moving and staying in position to supply air to port A or port B, when it gets power only momentary to allow air into port A or B allowing for small adjustments of a cylinder. As stated above this can be tricky since the air in the cylinder isn't the full regulated pressure but an average and can act like a spring. If you are interested in these contact SMC and they can help you select the proper one for your situation.