Dynamic manipulation of ball-in-cup game

This paper discusses robot motion planning in dynamic environments, and especially generation of a motion pattern of a manipulator to achieve a task under restrictions of time and space. We focus on a game of “kendama” (Japanese ball-in-cup game) that requires such a task. We do not intend to make robots mimic the actions of human being, but we discuss robots acting based on outside sensory feedback signals. In the “kendama” task, the robot learns physical properties through trials, because no a priori knowledge of both the mass of the ball and the length of the string is available. This paper proposes a method to generate the motion pattern of the manipulator with a force sensing device attached to the end tip to perform the “kendama” task. Experimental results obtained using a two DOF direct-drive manipulator are also shown