One way separation principle for a class of nonlinear observers and the robust stability analysis

This work discusses a one way separation principle for a class of nonlinear observers which are in recursive nature, including the widely-used extended Kalman filter. Given that the system has local observability and Jacobian matrices satisfying certain conditions, the stability property of the nonlinear observers is not affected by the control action when a controller is integrated in the output-feedback scenario. Then the robust stability of the closed-loop system is presented when the nonlinear observer and nonlinear model predictive control are used.