Nonlinear Hybrid Controller Design for Perturbed Quadrotor Robot by Uncertainties

In this paper, a novel nonlinear hybrid observers (HOB) based dynamic surface control (DSC) system, which integrates nominal and compensation controller, is designed for autonomous quadrotor robot perturbed by the uncertainties, e.g., external disturbances and measurement-delay. In this hybrid control system, the nominal controller based on dynamic surface control superior to the backstepping technique is the main controller, and the disturbance observer (DOB) is incorporated as the compensation controller to eliminate the effect of uncertainties caused by model mismatch and external disturbances. In addition, in order to relax the impact of measurement-delay induced by sensors of poor quality and heavy computation burden, the measurement-delay observer (MOB) is derived. Next, stability of the closed-loop control system is analytically proved based on Lyapunov theorem. Finally, comparative controllers are evaluated on simulation and experimental environments to demonstrate the effectiveness and merits of the proposed controller for quadrotor robot against the uncertainties.