GPC versus H∞ Control for Fast Visual Servoing of a Medical Manipulator including Flexibilities

Abstract

In this paper is considered fast visual servoing of a two-links arm including flexibilities for compensation of heart movements in surgery. The flexibilities are globally identified with no additional sensor than the external-500 Hz camera used in the visual servoing loop. The obtained model is valid around the working position of the arm and can be easily modified for new positions of the camera. Two control strategies to handle flexibilities and achieve high bandwidth are implemented: Generalized Predictive Control (GPC) and H∞ control. Simulation and experimental results are given allowing to compare their efficiencies.