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Robust trajectory tracking control for quadrotor unmanned aerial vehicle based on extended state observer

In this paper, a robust trajectory tracking control for the underactuated quadrotor unmanned aerial vehicle (UAV) based on extended state observer(ESO) is proposed. In the presence of external disturbances and inner model parameter uncertainty, it guaranteed that the position and yaw angle could track the reference signal speedily and smoothly. According to the strict feedback architecture of the system, the backstepping control is adapted to design the controller. For avoiding the complex calculation, the interference is observed by ESO and the algorithm composites the interference in the control law. For avoiding the problem of explosion of terms in backstepping control and improving the robust, the dynamic surface control method and the sliding mode surface are applied to design the controller. The closed-loop control system is analyzed and the sufficient stability conditions are derived based on Lyapunov theory. Numerical examples are presented to verify the proposed method.