A Bilateral Control Method for Master-Slave Grasping and Manipulation System

A human operator generally feels the gravity of a grasped object through a bilateral grasping system. It interferes with his manipulation of the object. This paper discusses a master-slave grasping and manipulation system. Different bilateral controllers are applied in the horizontal axis in which gravity doesn´t act and the vertical axis in which gravity acts. The bilateral controller in the horizontal axis realizes that the operator feels reaction force added to the slave manipulators from the grasped object. In the vertical axis, we propose a method for estimation of reaction force added to the object from an environment when the object contacts with environment. The bilateral controller in the vertical axis reproduces the reaction force in master side. With this bilateral controller, the grasped object can contact with environment, and the operator feels reaction force from the environment without feeling the gravity of the object. Simulation and experimental results show the validity of the proposed method