H-infinity Output Feedback Control: Application To Unmanned Aerial Vehicle

Abstract

This dissertation presents new necessary and sufficient conditions for static output-feedback control of linear time-invariant systems using the H-Infinity approach. Simplified conditions are derived which only require the solution of two coupled matrix design equations. It is shown that the static output-feedback H-Infinity solution does not generally yield a well-defined saddle point for the zero sum differential game; conditions are given under which it does. This work presents a simplified parameterization of all H-Infinity static state-feedback controllers in terms of a single algebraic Riccati equation and a free parameter matrix. As a special case, necessary and sufficient conditions for the existence of an H-Infinity static output feedback gain are given. This work also proposes three numerically efficient solution algorithms for the coupled design equations to determine the static output-feedback gain. In two of the algorithms an initial stabilizing gain is not needed. Correctness of these algorithms is proved. These algorithms also give flexibility to relatively weight control input and system performance. Application to Unmanned Aerial Vehicle exemplifies the power of the theory developed. This work give a procedure for designing compensators of specified structure for shaping the closed loop response that uses H-infinity output-feedback design techniques. The method developed takes advantage of the wealth of experience in aerospace control design. This work also presents the implementation of L2 Gain Bounded Static Output-Feedback control on Electromechanical Systems. Finally some future applications are explored including wireless networks.