Micro Hand with Two Rotational Fingers and Manipulation of Small Objects by Teleoperation

A micro hand consisting of two rotational fingers is proposed. Each finger has 4 DOF: 3-DOF translation and 1-DOF rotation around the finger´s axis. Two fingers grasp a small object and translate it in 3D space by moving themselves in the same direction. They can rotate the object by moving themselves back and forth in the opposite direction. Rotating the fingers around their own axes in the same direction makes it possible to rotate the object around another axis. Rotating the fingers in the opposite direction leads to move up and down the object between the fingers. Virtual stick method for teleoperation of this micro hand is also proposed. A human operator commands the 3-DOF translation and 2-DOF rotation of the grasped object using a PHANTOM omni-device, as if he directly grasps and manipulates the stick which is virtually fixed to the object. The commanded motion of the object is converted to the motions of the two fingers, which are input to the controllers of the fingers. As a preliminary experiment of the proposed micro hand, two rotations of a small spherical object of 2[mm] diameter are tested using two 2-DOF fingers.