Experimental demonstration of the grasp admittance center concept

The authors describe experiments wherein a carefully built passive compliant device emulates the dynamic behavior of multifingered grasps. The device is used to demonstrate the change in the time response of three types of grasps: (i) a grasp in a general situation, (ii) a grasp with a compliance center only, and (iii) a grasp with an admittance center. The experimental results (photographic records) of the time response of the three grasps clearly indicate the directionally decoupled dynamic behavior of an admittance center grasp, and the absence of such a behavior in general grasps and in grasps with a compliance center only. Such decoupled behavior is highly desirable in tasks involving constrained manipulation of delicate objects