Robust high order augmented observer based control for nonlinear systems

We propose a robust high order augmented observer (RHOAOB) based control for nonlinear systems. The RHOAOB is designed to estimate full state and a disturbance. The disturbance includes the unmeasurable external disturbance and model uncertainties for nonlinear systems. The performance of the RHOAOB is analyzed in the frequency domain, as well as the state space. For the output feedback control, the controller is implemented using backstepping procedure. The RHOAOB based control is robust to external disturbances and model uncertainties. Furthermore, the proposed method requires only system dimension.