Safety Control for the Quadrotor Unmanned Aerial Vehicle Despite Complete Lose of One Rotor

This paper focus on the fault tolerance control associated with complete loss of controller one rotor for the quadrotor unmanned aerial vehicle(UAV). As the quadrotor UAV is widely used in many industrial filed, it is critical to ensure the safety flight even when losing one rotor completely. The quadrotor UAV is a typical compact under-actuated mechanical system, which indicating that there is no more redundant generated thrust when one of the four rotors is complete loss. Thus, in this paper, the dynamic model of the quadrotor is degraded, and the yaw control is sacrificed for stabilizing the attitude and the altitude control. Then, the reduced attitude controller is proposed for maintaining the flight property when losing one rotor completely, and the disturbance observer is combined to compensate the modelling uncertainties and the unknown external disturbances. Furthermore, the integral geometric position controller is also developed to guarantee the flight performance under the effects of unknown external disturbances. The stability of the control system is ensured via the Lyapunov based stability analysis. At last, numerical simulation results are provided to verify the effectiveness of the proposed control strategy. The good position and attitude tracking performance can be achieved despite complete loss of one rotor.