How to replace a 4 prong valve with two 2 prong valves

Nathan4

I've built this model based on the "cylinder drive closed loop" Demo. The only differences between this and the demo is that I have removed some components. I would like to replace the valve (PropValve43PT2) with two 2 prong valves (PropValve22PT2) because it more accurately represents a physical model I have. I tried to directly replace it and split the input but to no surprise it didn't work. Can anyone help me figure out how to change the valve?

Orestis_YB

Hello @Nathan4 ,

as you already expected you can't just switch the valve and just split the signal to the cylinder. A proper substitution of the PropValve43PT2 would look like the picture below

The right port of the cylinder is connected to the pump and it's always pressurized. The right port is connected to two PropValve22PT2. One will be connected to the pump and the other to the tank. This is the only way to still have the similar dynamics for extending and retracting the cylinder. For driving signal you can still use the build-in PID but for the valve that is connected to the tank you need to revert the driving signal by using a gain with value of -1 like shown in the picture.

As you can see we can see similar behavior but pressure on side B now is always the supply pressure.

I have attached the model as well for reference. Hope this helps!

cylinder_new.scm

Best regards,
Orestes.

cylinder_new.scm