Automatic evaluation of two-fingered grips

Grip determination is essential to any task-level planning process. The complete force/moment equations are presented for grasping employing a rigid two-fingered gripper with a thin elastic layer on the contacting surface. The surface contact is modeled as a linear pressure variation. The quality measure of a grip is taken to be the coefficient of friction needed to keep the held object from slipping between the fingers under applied forces and moments. The lower the coefficient of friction, the better the grip. Incorporation of this evaluation into general grip selection strategy is discussed, and several examples are given.