Introduction

Abstract

Control theory has been extremely successful in dealing with linear time-invariant models of dynamic systems. A blend of state space and frequency domain methods has reached a level at which feedback control design is systematic, not only with disturbance-free models, but also in the presence of disturbances and modeling errors. There is an abundance of design methodologies for linear models: root locus, Bode plots, LQR-optimal control, eigenstructure assignment, H-infinity, µ-synthesis, linear matrix inequalities, etc. Each of these methods can be used to achieve stabilization, tracking, disturbance attenuation and similar design objectives.