Problem 3: How to deal with the saturation?

Q: For modeling this system, is the saturation of the control input a fundamental nonlinearity that we just toss out by assuming a local domain, or can this saturation be modeled formally?

A: In this problem, you're trying to prove stability about an equilibruim point -- thus, you can deal with the saturation of the control input by proving that it is linear in a region sufficiently close to the equilibrium point.

--Lindzey 07:55, 15 October 2006 (PDT)