ROBUST PERFORMANCE USING FIXED ORDER MIXED-NORM CONTROL

Fixed order mixed-norm controllers for the F-18 aircraft ape designed to minimize the effects of wind and sensor noise while following a nor mal acceleration command. The basic objective was to develop a control ler of low order that provides good wind and noise response while exhi biting robust performance in terms of command-following in the face of changing Fight conditions. Controllers were designed using single nor m methods as well as mixed H-2/H-infinity control with single and mult iple constraints and mixed H-2/mu optimization. Comparisons illustrate the advantages of mixed H-2/mu optimization with respect to noise res ponse and controller order while guaranteeing robust performance.