Simulink Signal and Physical Signal

I am new to Simulink although I'd been using Matlab for a long time. I am planning to use the Simhydraulic package.

I have two questions:-

1) I keep seeing demos having these Simulink signal to Physical signal thingies and I have totally no idea what that is for;

2) How do I simulate a constant pressure, say 250 psi?

Thank you all for your help!!

Answer 1

[Guy Rouleau]

You should be able to find what you need in the doc:

1. During Runtime, the Simscape engine combine all the components in your physical network into one big set of equations. You can see the S->PS and PS->S as the entry and exit point of this big set of equations.

A simpler way to see that... you can consider these blocks as a way to convert a unitless signal(in Simulink) into a signal with units (in Simscape), and vice-varse. More details here:

http://www.mathworks.com/help/toolbox/physmod/simscape/ref/pssimulinkconverter.html

http://www.mathworks.com/help/toolbox/physmod/simscape/ref/simulinkpsconverter.html

2. Using a ideal pressure source. The pressure source will generate as much flow as necessary to maintain the desired pressure:

http://www.mathworks.com/help/toolbox/physmod/simscape/ref/hydraulicconstantpressuresource.html

http://www.mathworks.com/help/toolbox/physmod/simscape/ref/hydraulicpressuresource.html

[Harry MacDowel]

Thank you so much Guy! Very helpful!