A Prosthetic Gripper with Three Opposing Fingers Driven by a Hydraulic Actuator

摘要

Electric prosthetic hands have problems of heavyweight, unsuitability for working near water, and driving noise. Although body-powered prosthetic hands solve these problems, they have operability and wearability problems related to a cable control system. In this paper, we report a prosthetic gripper with three opposing fingers driven by a hydraulic actuator without electrical components. The three fingers are controlled simultaneously by pushing the lever of an operating interface mounted on the user’s upper arm on the affected side. The hydraulic actuator enables users to open the fingers with a force of 16.6 N. The operating interface can be worn without a harness. The total weight is 316 g. Grasping tests of abstract and daily objects in which two amputees participated demonstrated that two amputees were able to grasp various objects. Quietness was also confirmed by them.