Stability analysis of 3D grasps by a multifingered hand
Stability analysis of 3D grasps by a multifingered hand
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多指手 3D 抓取的稳定性分析
DOI：
10.1109/robot.2001.932993
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Y. Funahashi
中科院分区：
文献类型：
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作者：
Takayoshi Yamada;Tarou Koishikura;Yuto Mizuno;N. Mimura;Y. Funahashi
利用三维弹簧模型(3D弹簧模型)讨论了三维抓取的稳定性。许多作品都描述了一种无摩擦的稳定性把握。这些工作通常使用一维弹簧模型(一维弹簧模型)来表示无摩擦接触。然而，一维弹簧模型涉及以下问题：(I)手指的位移被限制在接触点处的初始法线上的一维范围内；(Ii)没有明确地认为手指只沿法向对物体产生接触力。为了克服这些问题并提供准确的抓取稳定性，我们引入了一个三维弹簧模型。然后手指的位移被放松，手指的接触力被精确地表达出来。我们从势能法的角度分析了抓取的稳定性。数值算例表明，稳定抓取存在一个最佳接触力。此外，我们还利用纯滚动的接触运动学对摩擦抓取进行了分析。通过比较摩擦抓取和无摩擦抓取的稳定性，证明了摩擦可以提高抓取的稳定性。
We discuss stability of 3D grasps by using a three-dimensional spring model (3D spring model). Many works have described stability of a frictionless grasp. These works used a one-dimensional spring model (1D spring model) for representation of frictionless contact as a matter of course. However, a 1D spring model involves the following problems: (i) displacement of a finger is restricted to one dimension along the initial normal at contact point; and (ii) it is not clearly considered that a finger generates contact force to the object along the normal direction only. To overcome the problems and provide accurate grasp stability, we introduce a 3D spring model. Then a finger's displacement is relaxed and a finger's contact force is precisely formulated. We analyze grasp stability from the viewpoint of the potential energy method. From numerical examples, we show that there exists an optimum contact force for stable grasp. Moreover, we also analyze a frictional grasp by using contact kinematics of pure rolling. By comparing frictional grasp stability with a frictionless one, we prove that friction enhances stability of a grasp.