Robust and non-fragile H∞ controller design for affine parameter uncertain systems

Describes the synthesis of robust and non-fragile H^∞ state feedback controllers for linear time varying systems with affine parameter uncertainties and static state feedback controller with polytopic uncertainty. The sufficient condition of controller existence, the design method of a robust and non-fragile H^∞ static state feedback controller, and the region of controllers which satisfies non-fragility are presented. Also using some change of variables and Schur complements, the obtained condition can be rewritten as parameterized linear matrix inequalities (PLMls), that is, LMIs whose coefficients are functions of a parameter confined to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed loop system in spite of controller gain variations within a resulting polytopic region