Robust fault-tolerant control for quadrotor UAVs with parameter uncertainties and actuator faults

In this paper, a novel robust composite sliding mode controller (RCSMC) is proposed to accommodate actuator faults for a quadrotor UAV subject to unknown disturbances. The closed-loop system is divided into two parts: the nominal system without disturbances which is controlled by the designed baseline controller, and the equivalent total disturbances including parameter uncertainties and actuator faults, which is estimated by the developed adaptive finite-time extended state observer (AFTESO). The estimated total disturbances are rejected by RCSMC and the asymptotic stability of flight control system is guaranteed. The proposed method is verified through numerical simulations.