Fault-tolerant control design against actuator faults with application to UAV formation flight

This paper presents a fault-tolerant control (FTC) strategy against actuator malfunctions, with application to formation flight of multiple unmanned aerial vehicles (UAVs). Within the leader-follower context, the FTC mainly consists of the outer-loop control and the inner-loop fault accommodation. The reference commands for the follower UAV are generated by the inner-loop of the follower UAV. The inner-loop FTC is designed based on sliding mode control (SMC) and model reference adaptive control (MRAC) approaches, such that the adverse effects induced by failed actuators can be counteracted within finite time. Within the presented FTC scheme, both the finite-time convergence of the adaptive laws and the finite-time stability of the post-fault UAV can be ensured. The effectiveness of the proposed FTC approach is illustrated by simulations of UAVs formation flight.