Observer-Based Super Twisting Sliding Mode Control For Fixed Wing Unmanned Aerial Vehicle

Fixed-wing unmanned aerial vehicle (UAV) should be under control in the presence of model uncertainty and external disturbance, which is considered as torque perturbation in this paper. Such a challenge imposes tight requirements to the enhanced robustness and accuracy of the vehicle autopilot. The key of this paper is to introduce the model of attitude dynamics and propose a novel finite-time observer-based super twisting sliding mode control scheme for fixed-wing UAV. The observer designed in this paper can not only estimate the attitude rate but also the torque perturbation exactly in finite time. Then combined with the observer, a continuous homogeneous second-order sliding mode controller based on the terminal sliding mode and super twisting algorithm is designed to achieve a finite-time and exact attitude tracking with chattering attenuation. Finally, some simulations are provided to verify the effectiveness and robustness of the integrated control scheme in attitude tracking.