Grasp and Transport Control of a Chopsticks-Type Robot

In this paper, a method for changing the control mode based on position and force errors called the SCOME method is applied to a two-fingered robot hand composed of elastic joints. This robot is called a chopsticks-type robot and a cylindrical object is grasped and transported by the robot. First, we propose a control strategy for the robot based on a desired value of position and force for grasping and transporting an unknown object. Second, we explain the SCOME method, in which the control mode is selected on the basis of the point on the characteristic curve of position vs. force where the target value of work required to obtain the desired position and force is satisfied. Next, a grasp and transport control experiment is conducted using the robot to manipulate various objects made of different materials and with various outer diameters. The experimental results illustrate the validity of the chopsticks-type robot.