Motion planning and design of a dexterous gripper-virtual gripper and manipulable regions

We describe "graspability", "manipulability" and "virtual gripper". These concepts are necessary to deal with the geometric relation between a dexterous hand and its grasped object in both the planning and designing processes. Since the coordination of motion of the manipulator and manipulation of its gripper is needed in order to achieve the desired motion of the grasped object, we develop an algorithm that generates these coordinated motions: the path of the manipulator and the manipulation path of the object with respect to the coordinate frame of the gripper. This paper describes "graspability", "manipulability", "virtual gripper", an algorithm that generates the coordinated motions, and estimation of a "manipulable region" of a dexterous gripper which is needed in a specific task.