Modeling of Viscoelastic Contacts and Evolution of Limit Surface for Robotic Contact Interface
Modeling of Viscoelastic Contacts and Evolution of Limit Surface for Robotic Contact Interface
复制标题
机器人接触界面的粘弹性接触建模和极限表面演化
DOI：
10.1109/tro.2006.889494
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发表时间：
2007
影响因子：
7.8
通讯作者：
I. Kao
中科院分区：
文献类型：
--
作者：
P. Tiezzi;I. Kao
粘弹性接触是一种接触类型，它除了包括线性或非线性弹性响应外，还包括由于控制接触行为的松弛或蠕变现象而产生的随时间变化的响应。这种粘弹性接触的随时间变化的松弛特征分别是典型的指数衰减函数和蠕变指数增长函数。这种接触可以在拟人化的机器人手指、柔软的材料、具有刚性核心的粘弹性皮肤以及人类的手指和脚中找到。本文研究了粘弹性接触的性质，研究了它们的摩擦极限面和接触界面压力分布的演化。讨论了机器人抓取和操作中常见的两种情况。基于该模型，发现由于粘弹性接触界面随时间的变化，可以利用所提出的耦合方程来选择对这类接触进行分析和建模的两个重要参数，即接触面积半径和压力分布曲线。本文的新贡献包括提出了描述粘弹性接触界面的两个重要参数之间的耦合方程，研究了粘弹性接触界面的极限面随时间变化的规律及其对抓取稳定性的影响。从极限面的演化可以发现，当法向力作用于典型的粘弹性接触时，随着时间的推移，抓取变得更加稳定。该模型可应用于手指指尖的设计和粘弹性手指的机器人抓取和操作分析
Viscoelastic contact is a type of contact which includes, in addition to linear or nonlinear elastic response, time-dependent response due to relaxation or creep phenomena that govern the contact behavior. The characteristics of the time-dependent relaxation of such a viscoelastic contact are typically exponentially decaying functions, and exponentially growing functions for creep, respectively. Such contacts can be found in anthropomorphic robotic fingers, soft materials, viscoelastic skin with rigid core, and human fingers and feet. In this paper, the nature of viscoelastic contacts is investigated, and the evolution of their friction limit surfaces and of the pressure distributions at the contact interface are studied. Two cases commonly found in robotic grasping and manipulation are discussed. Based on the modeling formulation, it is found that the two important parameters of analysis and modeling for such contacts, i.e., the radius of contact area and the profile of pressure distribution, can be chosen using proposed coupling equations as the viscoelastic contact interface evolves with time. The new contribution of this paper includes a proposal of coupling equations between the two important parameters to describe the viscoelastic contact interface, and a study of the evolution of limit surfaces for viscoelastic contact interface due to temporal dependency, and the implication on grasp stability. It is found from the evolution of limit surfaces that when normal force is applied with typical viscoelastic contacts, grasp becomes more stable as time elapses. The modeling can be applied to the design of fingertips and the analysis of robotic grasping and manipulation involving viscoelastic fingers