Nonlinear Disturbance Observer based Dynamic Surface Control for Trajectory Tracking of a Quadrotor UAV

Abstract

In this paper, a nonlinear disturbance observer based dynamic surface control scheme is proposed for trajectory tracking of a quadrotor UAV in the presence of the unknown external disturbances. As a stepping stone, the nonlinear disturbance observer is firstly introduced to estimate and compensate for the disturbances of the attitude and position control subsystems, respectively. With the reconstruction information deriving from the disturbance observer, the robust attitude and position tracking controllers are designed utilizing dynamic surface control technique. Thereby, the ultimately uniformly bounded stability of the closed-loop trajectory tracking control system of the quadrotor UAV is guaranteed using Lyapunov method. Finally, numerical simulation results illustrate the fine performance of the proposed nonlinear disturbance observer based dynamic surface control scheme.