Direct adaptive control for aircraft control surface failures

A direct model reference adaptive controller for multi-input multi-output plants is analyzed. We augment the plant with feedforward dynamics such that the inverse feedforward stabilizes the plant over the set of allowable failures. We prove that the augmented output error is asymptotically vanishing for a loss of control effectiveness failure. A novel state space approach for computing the feedforward dynamics is proposed. We demonstrate the use of our algorithm by application to a three input model of the linearized lateral dynamics of the F/A-18 aircraft. Simulation results are presented which show that the adaptive controller exhibits improved model following as compared to a fixed gain eigenstructure assignment controller.