EXTREMAL ROBUSTNESS PROPERTIES OF MULTILINEAR INTERVAL SYSTEMS

This paper deals with robustness properties of a control system subjec t to parameter uncertainty when the parameters appear affine multiline arly in the coefficients of the characteristic polynomial. The robust Hurwitz stability of such a multilinear interval polynomial family red uces to that of the stability of a set of manifolds derived from the K haritonov polynomials. Several extremal properties of these stability manifolds are derived. These properties are useful in determining the worst case parametric, H(infinity) and nonlinear sector bounded stabil ity margins for control systems containing interval parametric uncerta inty. They generalize previous results obtained by the authors for the linear case.