Extended State Observer-Based Sampled-Data Control for a Class of Uncertain Nonlinear Systems

In this paper, a sampled-data output feedback controller is proposed for a class of nonlinear systems with unknown nonlinear dynamics and unknown external disturbance. To estimate the unmeasurable states and the modeling uncertainties, an extended state observer is constructed. Then, a sampled-data output feedback controller is designed via backstepping design technique. The explicit formula of sampling period T is derived to guarantee globally uniform ultimate boundedness of the closed-loop system under the developed control scheme. Finally, a simulation example is given to illustrate the effectiveness of the proposed approach.