Stability margin and robust control of systems with parametric nonlinear perturbations

A report is presented of results obtained by applying an algorithm presented in Vicino, Tesi, and Milanese (1988, 1990) for computing stability margins of linear control systems whose state matrix entries are polynomial (or rational) functions of a vector of physical uncertain parameters. The algorithm has been used on some meaningful application examples, giving a positive answer to important questions about the actual effectiveness of the algorithm both from computing time and numerical precision points of view