Reducing the Measure of Mismatch for Uncertain Dynamical Systems

We treat the robustness problem of uncertain dynamical systems that do not satisfy the so-called matching conditions. We consider controls which assure practical stability of the associated matched dynamical system. After introducing the notion of measure of mismatch, various conditions are stated, whose satisfaction assures that the mismatched uncertain system is practically stable under such a control. We also show that, under certain conditions, uniform attractivity can be assured; this has the advantage of reducing the measure of mismatch, and hence places lesser restrictions on the allowable magnitude of the uncertainty.