Robust Morgan's problem

Abstract

The robust Morgan's problem, via restricted static state feedback and a constant precompensator, is studied for nonsquare linear time-invariant systems with nonlinear uncertain structure. Sufficient solvability conditions are established.. A class of static controller matrices, independent from the uncertainties, to solve the problem is explicitly characterized. For this class of controllers, the resulting form of the robustly decoupled closed-loop system is analytically determined. Finally, sufficient conditions are established for the solvability of the robust Morgan's problem with simultaneous robust stability, via restricted state feedback. The present results are successfully applied to control a vertical takeoff and landing aircraft.