Visualization of form-closure and force distribution for grasping solid objects

This paper presents an analysis of the mechanics for grasping general solid objects. We prove that any disturbing force/moment pair at the mass center of an object can be balanced (or form-closure) if there exist a particular set of internal forces falling inside the friction cone of the contact points. Sufficient conditions for the geometrical properties of the contact points guaranteeing the existence of such internal contact forces are investigated. A new systematic way of generating the feasible contact forces is proposed