混合工作模式欠驱动手设计及其接触力分析  

Design and Contact Force Analysis of Under-actuated Manipulator with Hybrid Working Mode

作　　者：李小彭[1] 郭军强 孙万琪 尚东阳 闻邦椿[1] LI Xiaopeng;GUO Junqiang;SUN Wanqi;SHANG Dongyang;WEN Bangchun(School of Mechanical Engineering and Automation,Northeastern University,Shenyang 110819)

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819

出　　处：《机械工程学报》2021年第1期8-18,共11页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51875092);中央高校基本科研业务专项资金(N170302001)资助项目。

摘　　要：机器人手目前主要应用于机器人与环境的交互。传统欠驱动机器人手的手指末端运动轨迹并不是一条直线,这种运动轨迹使得它们无法抓取桌面上较薄的物体以及小物体。为了克服这个缺陷,许多研究者在欠驱动手结构中加入了直线机构,使其能够捏取平台上的物体,但目前存在的结构均为双指关节结构,相对于三关节手指其抓取范围较小且适用场合较少。为了解决以上问题,设计了一种新型的基于变胞原理的欠驱动手。手指具有三个指关节,它拥有两种工作模式:线性平行捏取模式和自适应抓取模式。在线性平行捏取模式下,该欠驱动手指可视为双关节手指,拥有更好的稳定性;在自适应抓取模式下,该欠驱动手指可视为三关节手指,拥有更大的工作空间且能更好地抓取不规则物体。该机构可以根据目标物体的尺寸、位置和形状特征自适应的改变工作模式。对欠驱动手的手指部分进行运动学分析以及接触力的分析,为设计提供理论参考。制作样机进行抓取试验,试验结果表明,该手拥有较大的适用范围并具有良好的抓取性能。At present, robot hand is mainly used in the interaction between robot and environment. The finger end trajectory of the traditional underactuated robot hand is not a straight line, which makes it impossible for them to grasp the thinner objects and small objects on the desktop. In order to overcome this defect, many researchers add a straight-line mechanism to the underactuated hand structure, so that it can grasp the objects on the platform. However, the existing structures are all structures with two knuckles, which have smaller grasping range and less application occasions compared with the structures with three knuckles. In order to solve the above problems, a new type of under drive operation based on the theory of metamorphic principle is designed. The finger has three knuckles. It has two working modes: linear parallel pinching mode and adaptive grasping mode. In the linear parallel pinching mode, the underactuated finger can be regarded as a two joints finger with better stability;in the adaptive grasping mode, the underactuated finger can be regarded as a three joints finger with larger working space and better ability to grasp irregular objects. The mechanism can adaptively change the working mode according to the size, position and shape characteristics of the object. In order to provide theoretical reference for design, kinematic analysis and contact force analysis are carried out on the finger part of under-actuated manipulator. The experimental results show that the hand has a wide range of application and good grasping performance.

关 键 词：变胞机构 机械手 欠驱动 运动学 接触力 

分 类 号：TH112[机械工程—机械设计及理论]