Abstract
While there have been a number of works on enveloping grasp, most of them have discussed the robustness of grasp, analysis of contact forces, and localization of contact points, under the assumption that robot fingers already grasps the object. This paper relaxes the assumption and treats an issue on planning torque commands for lifting up the object on the table till it makes contact with the palm. We first define a concept of transition stability during lifting motion and introduce the force-flow-diagram which is a convenient tool for evaluating the global moving direction of object. We show a couple of simulation results for both 2D and 3D objects.