Adaptive compensation of morphing actuator failures

We develop an adaptive approach for compensating uncertain failures of morphing actuators used for flight control of morphing aircraft. Morphing actuators are special actuators that operate at only two states: "on" and "off", and are used in a large quantity. Failures of such actuators are characterized by some actuators being stuck at one state and unable to be changed by applied control inputs. We present a novel failure model for such actuators, by considering the failure percentage as an uncertain parameter, and derive a piecewise-linear characteristic to describe such failures. We develop an adaptive inverse of such characteristic to compensate for the uncertain actuator failures. Updated from a parameter projection adaptive law and combined with a state feedback control law, such an adaptive inverse compensation scheme is able to ensure the desired closed-loop stability and tracking properties in the presence of uncertain actuator failures. An application of this compensation scheme to the control of an ICE aircraft model with morphing actuators is studied and the simulation results are presented to illustrate the effectiveness of the actuator failure compensation design.