Speed of a cylindre

[FMorin]

I'm looking for a way to estimate the speed of a pneumatic cylinder. Is there some empiric formula predicting this? Where can I find references?

Many thanks

 

[israelkk]

Can you give more info?

Basically, the pressure inside the cylinder creates force on the piston which pushes the piston against load and inertia. Using the second law of Newton you can calculate the acceleration, speed and displacement. The problem is to calculate the pressure changes with time inside the cylinder. This is quite complicated because you have to solve the mass flow rate into the cylinder, the resulting pressure change, the volume change (due to the piston movement), gas temerature change, etc.

The only way is to create a set of differential equation which are non-linear and solve them numerically.

 

[FMorin]

That's what i would like to avoid.

I've already seen a kind of formula taking in acount the length of the tube, the rate flow, the bore diameter of the cylinder and other things... but can't put my hands on it.

That's why I posted here to see if someone knows about it.

thank anyway

 

[Raedle]

Many cylinder manufacturers provide free software that can be used to calculate speed, flow, etc.

Check out FESTO ProPneu software. Maybe you can adapt their software to your problem.

http://www.festo.com/INetDomino/coorp_sites/en/61d22ceb41391b1ac1256b41003afdaf.htm