Constructing Stable Grasps

Abstract

This paper shows how all force-closure grasps can be made stable by constructing virtual springs at the contacts, such that the grasped object has a desired stiffness matrix about its stable equilibrium. The paper develops a simple geometric relation between the stiffness of the grasp and the spatial configuration of the virtual springs at the contacts. The stiff ness of the grasp also depends on whether the points of con tact stick or slide without friction on straight or curved edges or faces of the object.