Grasp stability analysis of two objects with both friction and frictionless contacts in two dimensions

This paper analyzes grasp stability of two objects with both friction and frictionless contacts in two dimensions. In the grasp of two objects, there exist multiple contact points which mean one contact point between two objects and plural contact points between objects and fingers. In the previous work, all these contact points are assumed to be either only with friction or only without friction. This paper discusses more practical grasp, in which there exist both friction contacts and frictionless contacts. In this case, both rolling motions and sliding motions occur due to friction contact and frictionless contact in the grasp system simultaneously. The grasp stability is evaluated by the potential energy stored in the grasp system. By using numerical examples, effect of friction is demonstrated