Reconfigurable flight control

Abstract

Indirect adaptive control for reconfigurable flight control is advocated. Specifically, online static system identification using a moving window/batch estimation is implemented. The ensuing linear regression is augmented with an intercept. The intercept parameter is included to address the effects of trim change associated with the occurrence of a control surface failure. Parameter estimate information is used to adjust the inner loop's control gains, and a command derived from the intercept estimate is fed forward to automatically retrim the aircraft. The tracking performance of this automatic retrimming method, which relies on system identification, surpasses the conventional approach of exclusively relying on integral action for retrimming. These adaptive and reconfigurable flight control concepts are illustrated in the context of a fighter aircraft's pitch plane dynamics. The novel adaptive and reconfigurable flight control system successfully handles a 50 per cent horizontal tail control surface loss.