Development of a Five-fingered Robot Hand using Ultrasonic Motors and Elastic Elements

Abstract

A robot hand imitating human hand is developed. The robot hand is driven by a new method proposed by authors using ultrasonic motors and elastic elements. The method utilizes restoring force of elastic element as driving power for grasping an object, so that the hand can perform the soft and stable grasping motion with no power supply. In addition, all the components oare placed inside the hand thanks to the ultrasonic motors with compact size and high torque at low speed. Applying the driving method to multi-DOF mechanism, a five-fingered robot hand is designed and implemented. It has equal number of joints and DOF to human hand, and it is also equal in size to the hand of average adult male. The performance of the robot finger is confirmed by fundamental driving experiments.