Abstract
This paper proposes a tendon-driven mechanism for a dexterous robot hand with passivity. A human hand has dexterity to grasp various shapes of objects since it can passively change its grasping configurations according to the shape of an object and to the grasping force. Therefore six tendons of a human finger that play major roles to grasp are selected and are simulated by an artificial tendon-driven mechanism. A tendon-driven mechanism and a back-drivable actuator can realize a passive property. That is a finger's attitude is determined by the interaction force with a grasping object's surface and by direction of a grasping force. A spring is inserted between a tendon and a conventional servo motor in order to realize the back drivable actuator. The passive property is mechanically realized so that the finger can respond to change of the grasping conditions without delay. As a result the passive robot hand can improve grasping stability against unexpected external force. The advantage and disadvantage of the proposed mechanism are investigated by some experiments.
