Augmentation Scheme for Fault-Tolerant Control Using Integral Sliding Modes

In this brief paper, a novel fault-tolerant control allocation scheme is proposed that has the capability to maintain closed-loop nominal performance in the case of faults/failures by effectively managing the actuator redundancy, and without reconfiguring the underlying control law. The proposed scheme relies on an a posteri approach, building on an existing state feedback controller designed using only the primary actuators. An ISM scheme is integrated with the existing controller to introduce fault tolerance. The proposed scheme uses the measured or estimated actuator effectiveness levels in order to redistribute the control signals to the healthy ones, which allows a certain class of total actuator failures to be mitigated. The effectiveness of the proposed scheme is tested in simulation using a high-fidelity nonlinear model of a large transport aircraft model.