QUADROTOR ROBUST PATH TRACKING WITHOUT VELOCITY MEASUREMENTS USING THE GENERALIZED SUPER-TWISTING CONTROL

Abstract

This paper presents a nonlinear control strategy to solve the path tracking problem for a quadrotor unmanned aerial vehicle under perturbations. This strategy is based on the Generalized Super-Twisting Algorithm (GSTA); it means the second order sliding mode technique, which is able to ensure robustness with respect to modeling errors and bounded external disturbances due to the added extra linear correction terms. The controller goal is to achieve suitable path tracking of desired absolute positions and yaw angle while keeping the stability of the pitch and roll angle, in spite of the presence of disturbances and the handling of all system nonlinearities. In this work, a scenario in which velocities measurements are not available and are estimated by the Generalized Super-Twisting Observer is considered. Finally, the simulation results are also provided in order to illustrate the performances of the proposed controller.

Keywords

• quadrotor; generalized super twisting; sliding mode control; observer; non-linear control