On robust non-fragile static state-feedback controller synthesis

This paper addresses the design of robust non-fragile state feedback controllers, with controller uncertain parameters described as polytope-type convex-bounded uncertainties. The linearizing change of variables Z = KW that is the basis for a large class of LMI-based robust control design algorithms is slightly modified. The modified change of variables proposed here leads to LMI-based robust nonfragile control design algorithms that are directly derived from any former algorithm formulated in terms of the traditional change of variables. In this way, the "fragility" issue is solved inside the mainstream of the LMI-based robust control synthesis algorithms that have been developed up to now, in a unified basis.