基于视觉非接触测量的少自由度运动平台试验研究

发布时间：2017-12-28 01:30

本文关键词：基于视觉非接触测量的少自由度运动平台试验研究　出处：《佳木斯大学》2016年硕士论文　论文类型：学位论文

【摘要】：并联机构以及混联机构,因其刚度大、精度高、响应快、负载大的优点,应用十分广泛。本文根据物料分拣场合的特点,在螺旋理论的基础上,提出一种运动平台(放置末端执行器)的具有三维移动及一维转动自由度,即1Rz3T型机,再有,平面机构,即1Rz2Txy型机构。另外,以以上述提出的两种机构为基础,提出了一种全自由度混联机构,结合了并联机构与串联机构的各自优点。根据混联机构的工作状况,采用基于视觉的非接触测量方式进行无损、无接触压力检测,测量系统具有很好的移植性。首先,在综述国内外螺旋理论及少自由度并联机构型综合的基础之上,根据应用场合例如:快递分拣等进行分析,确定了少自由度并联机构的构型以及全自由度混联机构的设计方案;在综述国内外现有摄像机标定的基础上,确定了摄像机标定方案,使得相机标定方便快捷、准确可靠;在综述机器视觉测量技术的基础上,对视觉测量系统进行了分析。根据现有的工作状况,将非接触测量与机构的运动平台相结合,确定了一种基于视觉非接触测量的少自由度运动平台总体设计方案,为后续的混联机构的工程应用提供基础。其次,基于螺旋基系理论,分析了1Rz3T四自由度和五自由度并联机构构型,提出一种新型1Rz3T四自由度运动解耦式并联机构,通过对1Rz2Txy对称型平面并联机构构型分析,提出一种3RRR型1Rz2Txy对称型平面并联机构,将这两种结构结合,构成全自由度混联机构。然后,研究了摄像机成像模型以及摄像机标定技术,分析了摄像机内参数、外部参数,并利用Matlab中标定工具箱对采集完成的棋盘格图像进行标定,求解了内参数、畸变参数等,为后续的3RRR型1Rz2Txy对称型平面并联机构的运动平台进行提供了基于视觉非接触测量的基础。最后,建立了试验系统,加工出了3RRR型1Rz2Txy对称型平面并联机构和1Rz3T四自由度运动解耦式并联机构。编写了3RRR型并联机构的运动平台的控制系统并对其运动平台作了位姿采集。
[Abstract]:Parallel mechanism and hybrid mechanism are widely used because of their advantages of high stiffness, high precision, fast response and large load. According to the characteristics of material sorting, on the basis of screw theory, this paper proposes a three dimensional movement and one dimension rotation degree of freedom of a motion platform (placing the end effector), that is, the 1Rz3T type machine, and then the planar mechanism, that is, the 1Rz2Txy mechanism. In addition, on the basis of the two mechanisms mentioned above, a kind of full degree of freedom hybrid mechanism is proposed, which combines the advantages of the parallel mechanism and the series mechanism. According to the working status of the hybrid mechanism, a non-contact and visual based non-contact measurement method is applied to detect lossless and non-contact pressure. The measurement system has good portability. First of all, on the basis of review of screw theory and less DOF parallel mechanisms based on comprehensive, applications such as: Express sorting analysis, the less degree of freedom parallel mechanism configuration and full freedom mixed design scheme of the organization; based on summarizing the domestic and foreign existing camera calibration, to determine the the camera calibration method, the camera calibration is convenient, accurate and reliable; on the basis of machine vision measurement technology, the visual measurement system are analyzed. According to the existing working conditions, a new design scheme of a less freedom motion platform based on visual non-contact measurement is established by combining the non-contact measurement with the motion platform of the mechanism, which provides a basis for the subsequent engineering application of the hybrid mechanism. Secondly, based on the theory of the spiral matrix, 1Rz3T four and five degree of freedom parallel mechanism analysis, put forward a new type of 1Rz3T four DOF motion decoupling parallel mechanism, through the analysis of the 1Rz2Txy symmetric planar parallel mechanism, put forward a kind of 3RRR type 1Rz2Txy type symmetric planar parallel mechanism, the combination of these two kinds of the structure, constitute full DOF hybrid mechanism. Then, the camera model and camera calibration technology, analyzes the parameters and external parameters of the camera, using the Matlab calibration toolbox of checkerboard image acquisition complete calibration for parameters and distortion parameters, motion platform of 3RRR 1Rz2Txy symmetric planar parallel mechanism in the future it provides the basis for non contact measurement based on vision. Finally, the experimental system was established, and the 3RRR type 1Rz2Txy symmetrical planar parallel mechanism and the 1Rz3T four degree of freedom motion decoupling parallel mechanism were worked out. The control system of the motion platform of the 3RRR type parallel mechanism is written and the position and attitude of the motion platform is collected.
【学位授予单位】：佳木斯大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TH112

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