simple position control of hydraulic cylinder

[030504030]

Hello

I asked before about servo but infact I want to control position of a hydraulic cylinder. How can I use servo valve and 3 preesure sensors ( one is for forward motion and the other is for bacward motion). Is it enough to control the servo valve's speed. What can I use for that in labview? Before I thought Labview 6.1 but I changed my mind maybe 7.1 or 8.5 I can use for my aim. Would you like to help me with how I can make that? My sensor can work 0-10 V and linear potantiometer is 0-10V and servo valve 0-5 V. 

For instance thank you very much.

[Andy_C.]

Are you doing position control or velocity control? You said you want to control the position of the hydraulic cylinder, but also mentioned the servo valve's speed. Do you have PID Toolkit?

[030504030]

Sorry my mind was confused then. 

I want to do control both velocity and position. I want to stop the hydraulic cylinder when it comes desired position and also control velosity because the cylinder will be used for mold. Firstly we want to send it fast and then when it starts to form the cylinder will be slow. I have PID toolkit. I have 2 pressure sensors and 1 linear potantiometer and DAQ card. Are they enough to do my aim. Thank you very much for your help.

[Andy_C.]

From the sensoring perspective, I believe you have all the pieces that you will need.

You can deduce velocity and position from your pot. However, the thing to look out for is you would essentialy need a Cascading PID Scheme for your application. I would recommend looking at Simulation - Cascade and Feedforward Surge Tank Level VI as reference. 

Also, what DAQ card do you have? How fast are you trying to sample? A USB6008/6009 is not the best for doing CL control...

[030504030]

Hi Andy

I will use PID. We decided to only control position  and I have 6024 DAQ card. Mine is not USB. I want to do control for example I stop the cylinder when it comes 60 mm and then I want to stop it 65 mm. Like that things. And also can I stop the cylinder which velocity I want? Thank you very much for your helps. 

N.Y

[Andy_C.]

Assuming you can deduce velocity from your sensors, you would be able to use your DAQ card for your application.