Hybrid controller with observer for the estimation and rejection of disturbances

In this paper, a hybrid controller with observer is introduced for the estimation and rejection of a disturbance. It is based on the combination of the sliding mode technique and the output feedback strategy. It is divided into two designs: (1) the observer and (2) the controller with observer. The observer is selected to reach two objectives: (a) to assure its stability and (b) for the estimation of a disturbance. The controller with observer is selected to reach three objectives: (a) to assure its stability, (b) for the rejection of a disturbance, and (c) for the decreasing of chattering in the sliding mode behavior. The proposed method is applied for the estimation and rejection of the disturbance in a plotter and a suspension system.