【作者】 孙宁；

【导师】 张伟民；

【作者基本信息】 北京理工大学 ， 机械工程， 2018， 硕士

【摘要】 作为机器人直接与环境接触的末端执行机构,机械手是机器人重要的组成部分。设计外形及功能与人手相似的多自由度仿人灵巧手,已经成为机器人领域的研究热点。近几年,由于欠驱动传动方案能够以较少的驱动单元驱动多个自由度,减轻灵巧手的质量,降低控制难度,因此,被广泛的研究。本文提出一种欠驱动的耦合与自适应并联传动方案,应用到仿人灵巧手中。采用欠驱动的耦合与自适应并联传动方案,有助于提高仿人灵巧手抓取的快速性,保证包络抓取,提高抓取稳定性。本文的研究内容如下:第一、本文分析了人手的抓取功能、骨骼结构、自由度布置及关节的运动机理,并且研究了抓取物体所需要的手指数目。借鉴人手的优点,本文总结出仿人灵巧手机构设计要点,使其对灵巧手的机构设计产生指导意义。第二、根据仿人灵巧手的机构设计要点,本文设计了一种采用欠驱动的耦合与自适应并联机构的仿人灵巧手。该灵巧手采用模块化设计理念,电机全部内置于手中,外形大小与人手相似。灵巧手包含耦合与自适应并联传动机构、两自由度差动锥齿轮传动机构,以及单自由度锥齿轮传动机构。本文描述了其各部分的机构设计,建立运动数学模型。其中,耦合与自适应并联传动机构能够使手指的运动拟人化,提高抓取速度,保证对物体的包络抓取,提高抓取稳定性。同时,受到关节脱臼的启发,本文设计了一种变驱动力矩的解耦装置,克服弹簧传动的不足。第三、本文建立灵巧手的各个手指以及整手的运动学模型,分析其运动空间。根据其运动空间,规划仿人灵巧手各手指的位姿,抓取不同物体,验证其抓取能力。分析灵巧手手指各指节的抓取力,验证抓取的有效性。最后,本文建立仿人灵巧手的仿真模型,验证耦合与自适应并联传动机构的运动机理,证明手指的自适应抓取能力,以及建立三种欠驱动方案的仿真模型,验证耦合与自适应并联机构的快速性。同时,建立灵巧手单手指物理模型,验证耦合与自适应并联传动机构的可行性。制作四指仿人灵巧手样机,验证其抓取能力。更多还原

【Abstract】 Mechanical hands,as the end effector of many robots directly contact with the environment,are an important part of robot.Mechanical hand similar to human appearance and function have become a hot research area in robotics.Recent years,under-actuated design that the number of actuators is less than its degree of freedom are widely studied because it can be adaptive to the object and reduce the control difficulty.Therefore,an under-actuated dexterous hand based on coupling and self-adaptation was proposed.Under-actuated design with coupling and self-adaptation helps to improve the grasping rapidity,ensure the envelope grasping and improve the grasping stability.The contents of this paper are as follows:Firstly,this paper analyses the grasping function of the hand,the structure of the skeleton,the arrangement of freedom degree and the movement mechanism of the joint,and studies the number of fingers for grasping the object.To absorb the advantages of human hands,this article summarizes the mechanical design criteria,which makes it instructive to the design of the dexterous hand.Secondly,based on the mechanism design criteria,an anthropomorphic dexterous hand with coupling and self-adaptation is designed in this paper.The dexterous hand adopts the modular design concept,the motor is all built in the hand,the shape and size are similar to the human hand.The dexterous hand includes the coupling and self-adaptation parallel transmission mechanism,the two degree of freedom differential bevel gear transmission mechanism,and the single degree of freedom bevel gear transmission mechanism.This paper describes the mechanism design of each part and establishes a mathematical model of motion.The mechanism with coupling and self-adaptation can make the motion of the fingers anthropomorphic,improve the grasping speed,ensure the envelope grasping,and improve the grasping stability.Inspired by joint dislocations,a decoupling device with variable driving torque is designed to overcome the shortage of spring.Thirdly,in this paper,the kinematic model of the fingers and the whole hand is established,and its motion space is analyzed.According to the motion space,the position and posture of the fingers of the anthropomorphic dexterous hand are planned,the different objects are captured and the grasping ability is verified.The grasping force of the fingers of a dexterous hand is analyzed in order to verify the effectiveness of the grasping.Finally,in this paper,a simulation model of an anthropomorphic dexterous hand is established to verify the motion of the mechanism with coupling and self-adaptation,and to verify the self-adaptive grasping ability of the finger.Three simulation models of under-actuated mechanism are established to verify the rapidity of coupling and self-adaptive parallel mechanism.A single finger physical model is established to verify the feasibility of the mechanism with coupling and self-adaptation.A prototype of four finger anthropomorphic dexterous hand is made to verify its grasping ability.更多还原