Stable Reference Trajectory Modification For Handling Actuator Failure In Control Systems

Abstract

The issue of rapidly reconfiguring the reference trajectory under unanticipated actuator failures in order to regain lost performance or aircraft handling qualities is explored. The failures detected in real-time are compensated for by ensuring the input to the system reflects current system conditions. This thesis will also show that only the general structure of the failed system component is needed to achieve successful failure detection and reference trajectory reconfiguration. This approach allows the nominal control structure to remain unchanged in the presence of change flight and system conditions. Acceptable system performance is recovered by detecting the actuator failures in real-time. The benefit of this approach is that the modification does not alter the control gains of the closed loop system which eliminates the apprehensionsassociated with most adaptive control techniques. The implementation of this technique will be done on a linear ongitudinal model of an F-16 like aircraft and the efficacy of the basic approach will be shown through computer simulations.