High speed robust visual servoing based on intersample estimation and multirate control

Abstract

This paper presents a visual servoing system based on intersample estimation and disturbance rejection. First, a novel design method of a multirate sampling controller is proposed which enables to reject disturbance completely at M intersample points in the steady state. Second, the intersample observer is developed in order to reduce the phase delay caused by zero-order hold and to increase the stability robustness. Third, the novel scheme of repetitive control is proposed based on the open-loop estimation and switching function, which enables the rejection of periodical disturbance without any sacrifice of the closed-loop characteristics. Finally, the proposed controllers are applied to visual servo system by introducing the workspace controller and nonlinear perspective transformation. The advantages of these approaches are demonstrated by simulations and experiments using a robot manipulator.