A Quantitative Test for Form Closure Grasps1

Grasp and manipulation planning of slippery objects often relies on the 'lform'closure" grasp, which can he maintained regardless of the external force applied to the object. Despite its importance, a quantitative test ,for form closure valid for any number of contact points is not availuhle. The primary contribution of this paper is the introduction of such a test formulated as a lineor program, of which the optimal objective value provides a measure of how far a grasp is from losing ,form closure. While the test is formulated for frictionless grasps, we discuss how it can be modified to identify grasps with 'yrictional fortn closure."