An Adaptive Actuator Failure Compensation Scheme for A Hexarotor System with Parameter Uncertainties

In this paper, an adaptive control design is developed for hexarotor systems subject to uncertain parameters and unknown actuator failures. The developed control scheme consists of a control signal distributor and a state feedback controller equipped with adaptive laws. It is verified that the control distribution matrix ensures that under different uncertain actuator failure patterns the controlled system has high frequency gain matrices whose equivalent signs are invariant. A nominal control scheme is first constructed for the case of known parameters and failures, to demonstrate the existence of the plant and reference model matching parameters. A multivariable model reference adaptive controller is developed to deal with system and failure uncertainties, using an LDS gain matrix decomposition based parametrization for the derivation of the estimation error and adaptive law. Such a control design effectively utilizes the controller adaptation and system actuation redundancy to compensate for possible uncertain actuator failures in the presence of system uncertainties. Simulation results are presented to verify the desired performance of the adaptive compensation scheme developed for hexarotor systems.