A Sampled-Data Scheme for Disturbance Rejection of Nonlinear Systems in Output Feedback Form

This paper presents a sampled-data control scheme for disturbance rejection of nonlinear systems in output feedback form. The continuous-time controller is designed first using a filtered transformation and the internal model technique. Obtained on an emulationbased approach, the proposed sampled-data control uses the sampled output and a discrete-time implementation of the filter and the internal model is involved. The proposed control is shown to render the overall system stable in a spirit of fast sampling. Specifically, the ultimate bound of the output is allowed to be arbitrarily small by choosing appropriate gain parameters.