Fixed-Time Extended Disturbance Observer-Based Robust Control for Quadrotor Vehicle

This paper proposes a novel output feedback robust tracking control of a quadrotor unmanned aerial vehicle (UAV). Since quadrotor UAVs encounters enormous and different types of exogenous disturbances such as wind during flight operation, the impact of such disturbances can degrades the system stability. To attenuate the influence of these disturbances fed into the system, a fixed-time extended disturbance observer (FTEDO) is developed that can accurately estimates the lumped disturbances based on which a sliding manifold is constructed and updated. The proposed control scheme also assure the tracking error converge to zero in fixed-time. A comparison of the proposed FTEDO is carried out with the conventional nonlinear disturbance observer (NDO) to affirm its enhanced disturbance estimation performance. The simulation results of the quadrotor with exogenous disturbances prove the robustness, efficacy and fast convergence rate of the proposed control scheme.