摘要为了对零件上二维几何特征进行高精度自动测量,建立了机器视觉测量系统,提出机器视觉多视场协同测量方法。介绍了系统的硬件组成、功能结构及工作原理,建立特征图像坐标与测量空间坐标之间的映射关系,在大视场图像上识别被测特征并规划测量路径;然后,根据测量路径完成小视场序列图像的自动采集;从而建立起大视场图像坐标与小视场图像坐标之间以及相邻小视场图像坐标之间的映射关系。据此关系,自动构造辅助测量特征并提取被测特征参数。应用该测量方法对零件孔距进行测量实验,结果表明:测量精度较高,相对误差的绝对值不超过0.03%。61179
毕业论文关键词 二维几何特征 机器视觉 协同测量
毕业设计说明书(论文)外文摘要
Title Research on the method of automatic measurement of machine vision
Abstract To realize high-precision automatic measurement of two-dimensional geometric features on parts, a system based on machine vision is constructed, a machine vision cooperative measurement method of multiple fields of view is proposed. Then its hardware structure, functional composition and working principle are introduced. The mapping relationship between the feature image coordinates and the measuring space coordinates is established. The feature to be measure is identified, and an optimized measuring path is planed in a large FOV image. Guided by the measuring path, the sequential images with small FOV are collected automatically, Furthermore, the mapping relationship between the images coordinates of the large FOV and the small FOV and that between the adjacent small FOV image coordinates are established. On the basis of these relationships, the auxiliary measuring characteristics are constructed and the parameters of the feature to be measured are automatically extracted. Experiment results show that the absolute value of relative error is less than 0.03% when applying the cooperative measurement system to measure the hole distance.
Keywords two-dimensional geometric features machine vision cooperative measurement
1 绪论 1
1.1 课题研究的背景及意义 1
1.2 机器视觉技术的发展及其在测量方面的应用 2
1.3 本课题主要研究内容 3
1.4 本章小结 4
2 机器视觉测量技术 5
2.1 数字图像的基本特性 5
2.2 数字图像硬件系统简介 6
2.3 视觉测量投影模型 8
2.4 本章小结 11
3 机器视觉测量系统及其标定 12
3.1 测量系统介绍 12
3.2 系统硬件选择 13
3.3 机器视觉系统的标定 15
3.4 本章小结 18
4 零件孔特征的多视场协同测量 19
4.1 测量路径规划与小视场序列图像自动采集 19
4.2 被测特征的参数获取方法 20
4.3 测量物理坐标与图像坐标的映射关系 20
4.4 大、小视场图像坐标之间的关系 22
4.5 本章小结 23
5实验分析与结果