Robust non-fragile LQ controllers: the static state feedback case

This paper describes the synthesis of non-fragile or resilient regulators for linear systems. The general framework for fragility is described using state-space methodologies, and the LQ/H₂ static state-feedback case is examined in detail. We discuss the multiplicative structured uncertainties case, and propose remedies of the fragility problem using a convex programming framework as a possible solution scheme. The benchmark problem is taken as an example to show how controller gain variations can affect the performance of the closed-loop system