The 522 Hybrid Simulator (the name is from me) is a hybrid systems simulator in python developped by Olivier Dubois and Eric McSween as a project for the course 308-522A in Fall 2001 (see their project web page). I have used it extensively as a starting point for my research this summer.
For some rough documentation about their simulator, you may consult
the relevant sections in my MSDL talk web page:
Here are all the files to run the simulator and some examples of model files:
To install the simulator, simply extract the python files somewhere where
you can use Python 2.1 or later (maybe earlier version also works, though).
Run GUI_new.py with Python and the simulator will start. To do something
interesting, you will need to load a model (a python file). You can simply load
the models given in the link above to get an idea of what you can do.
To build your own models, I suggest that you read
my pool table model example
(which is heavily commented) and try to follow the same format for your model.