Antisaturation Finite-Time Attitude Tracking Control Based Observer for a Quadrotor

This brief proposes an attitude tracking control method for a quadrotor subject to wind disturbance and input saturation. First, a finite-time extended state observer is designed to eliminate the wind disturbance and estimate the angular velocity. To achieve the fast finite-time convergence, singularity avoidance and chattering elimination, a fast nonsingular terminal sliding mode controller is developed. Next, an auxiliary system is constructed elaborately to address the input saturation. With the aid of Lyapunov technique, the stability analysis is provided to manifest that the tracking error converges to an arbitrarily small bounded region in finite time. Finally, simulation results demonstrate that the viability of the proposed control strategy.