Hi!
I have a material testing setup: A round, thin specimen is fixed in a testing device and then blown up by compressed air. The range of the air is 0-10 bar. I'm using a valve and a cRio-Module to control the compressed air, in which 1 bar=1 Volt! I'm also using an optical measurement system to measure the strains of the specimen during the test.
Now i want to do the following: The user should be able to define a min and max strain in a labview-program. Then the specimen should be "loaded" with the compressed air "between the strain-range". The strain of the specimen should be like a sine-curve (the user should also be able to choose the frequency of the sine strain-signal and also the test duration). I get the current strain from my optical system every 100 milliseconds (i also have this currrent strain in my labview program)
What i need is a conversion between strain and voltage(=pressure). The problem is, that the relation between strain and pressure is nonlinear.
I'm a labview-beginner, but i think i need a PID-control! But how can i use a PID and a sine-signal together. And how can i convert the strain to the right voltage/pressure (remember: nonlinear)? I'm using Labview 2011
I hope you can help me, thanks!
