Stability Analysis of Frictionless Grasps and Combining Frictional and Frictionless Grasps
نویسندگان
چکیده
This paper discusses the stability of 2D frictionless grasps and combining stability of frictional and frictionless grasps from the viewpoint of potential energy method. In many works related to the frictionless grasp, each finger is replaced by one directional virtual spring along the normal at the contact point. However, this condition is not accurate, because the frictionless condition does not mean one-spring model but means contact force condition. So, in order to represent the condition that the contact force directs to the normal at the contact point, a two-dimensional virtual spring model is essential. It is clarified that the relation between oneand two-spring cases. Some numerical examples are presented to verify our analysis. Moreover, stiffness condition of the spring for stabilization of the grasp is established. Finally, we derive stiffness matrix for both frictional and frictionless grasps from the same derivation.
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