Scilab is a piece of open-source software that implements a mathematical computation package that can do many things for mathematicians, scientists and engineers. Of particular interest to control engineers is its Xcos application.

Xcos is a graphical dynamic modelling environment that is great for designing and running simulations of processes and the control schemes that manipulate them.

If you thinking this sounds like what MATLAB / Simulink do then you would be correct!

BTW I think it is pronounced "silab" since an early project name was "ψlab". I started off pronouncing it "skylab" and got some strange looks!

How to get Scilab

You can download the lastest version for many platforms from the Scilab website at http://www.scilab.org.

Scilab uses for control engineers

Control engineers will normally be using the Xcos application found within Scilab to simulate a plant + controller. Xcos allows a control engineer to better understand the process, investigate possible controller designs and test different designs against each other to find the preferred design.

Here are some control examples from the built in demos;

Someone called Scilab Ninja has an excellent website which get you started with using Scilab & Xcos for process control.

See the Xcos section of the Scilab website for more details.