DESIGN OF NONLINEAR CONTROL LAWS FOR HIGH-ANGLE-OF-ATTACK FLIGHT

High-angle-of-attack flight control laws are developed for a supermane uverable fighter aircraft. The methods of dynamic inversion and struct ured singular value synthesis are combined into an approach which addr esses both the nonlinearity and robustness problems of flight at extre me operating conditions. The primary purpose of the dynamic inversion control elements is to linearize the vehicle response across the fligh t envelope. Structured singular value synthesis is used to design a dy namic controller which provides robust tracking to pilot commands. The resulting control system achieves desired flying qualities and guaran tees a large margin of robustness to uncertainties for high-angle-of-a ttack flight conditions. High-fidelity nonlinear simulation results sh ow that the combined dynamic inversion/structured singular value synth esis control law achieves a high level of performance in a realistic e nvironment.