DESIGN OF A ROBUST CONTROLLER FOR A SUPERSONIC AIRCRAFT USING H-INFINITY APPROACH

In this paper an H(infinity) optimal, robust flight control system design for a supersonic aircraft has been described. Separate controllers are designed for longitudinal and lateral motions. A general two-degrees-of-freedom controller is proposed, where feedback control is designed for robust performance augmentation, while a series compensator is used to ensure the requisite handling qualities. Three alternative methods to achieve performance robustness have been discussed. The results obtained are very encouraging. It is hoped that this approach will equip the flight control engineers with an alternative to the conventional methods.