Domain of attraction and guaranteed cost control for non-linear quadratic systems. Part 2: Controller design

This study addresses the problem of designing a guaranteed cost controller for non-linear discrete quadratic systems. More specifically, the main contribution concerns a sufficient condition for the existence of a state-feedback controller achieving a certain guaranteed cost, whenever the state trajectories start from a prescribed set of initial conditions. The controller design requires the solution of a convex optimisation problem involving linear matrix inequalities, which can be efficiently solved via available optimisation algorithms. Finally, the proposed design methodology is illustrated via an example concerning the attitude control of an unmanned aerial vehicle.