Local actuation of multijointed robotic fingers

Over recent years a number of advanced multi-fingered grippers have been developed for prosthetic and robotic applications. In all these designs, the crucial question is the location and the type of actuator used to control the individual finger joints. Where the individual finger joints are powered from actuators external to the hand, there is dexterous performance, but considerable problems with power transmission, due to the need to use flexible tendons between the actuators and the individual finger joints. For a multifingered gripper to operate successfully over a wide range of applications, local actuation of the fingers needs to be fully considered, even if there is a reduction in hand dexterity over that of an externally mounted actuator system. The paper reviews a number of possible designs for linkages and actuator that can be incorporated into robotic end effectors and prosthetic hands, including a number built at the University of Southampton.