Stability analysis of multiple objects grasped by multifingered hands with revolute joints in 2D

Abstract

We analyze static grasp stability of multiple planar objects. In our previous papers, we considered that each finger is replaced with an orthogonal virtual spring model. This means that each finger is constructed with prismatic joints. Human hands and the most developing mechanical hands are constructed with revolute joints. In this paper, we investigate the effect of fingertip rotation and revolute joints for grasping multiple objects. The stability is analyzed from the potential energy method. A grasp stiffness matrix is derived by considering not only frictional rolling contact but also frictionless sliding contact. The gravity effect of the objects is also considered. The stability is evaluated by the eigenvalues and eigenvectors of the grasp stiffness matrix. The effectiveness of our method is demonstrated through numerical examples.

Multiple-Object Grasping Using a Multiple-Suction-Cup Vacuum Gripper in Cluttered Scenes

“…Most studies have focused on multiple-object grasping using a multi-finger gripper. Grasp conditions have been analyzed for a multi-finger gripper to stably grasp multiple cylinders [28,29], polyhedral objects [2], planar objects [3], and shaped spatial objects [30]. Recent studies have started to use data-driven methods to deal with the multiple-object grasping problem.…”

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“…-Analytic 3D models with contacts -Rolling of finger against ball -Dynamics and slippage -Suitable for simulation as well as optimization There are elaborate mathematical models for studying contact stability [35,36]. In contrast, the purpose of the model developed here is to capture contact transitions and to find optimal trajectories.…”