ROBUST H-INFINITY CONTROL DESIGN FOR THE SPACE STATION WITH STRUCTURED PARAMETER UNCERTAINTY

A robust H infinity control design methodology and its application to a Space Station attitude and momentum control problem are presented. This new approach incorporates nonlinear, multiparameter variations in the state-space formulation of H infinity control theory. An application of this robust H infinity control synthesis technique to the Space Station control problem yields a remarkable result in stability robustness with respect to the moments-of-inertia variation of about 73% in one of the structured uncertainty directions. The performance and stability of this new robust H infinity controller for the Space Station are compared to those of other controllers designed using a standard linear quadratic regulator synthesis technique.