基于视觉的零件尺寸测量方法

摘    要

模仿人的眼睛看事物，将物体看作是一幅图像来获得物体的尺寸信息，依靠视觉来采集图像信息是基于视觉的零件尺寸测量主要研究的过程。这些年来，基于视觉零件尺寸的测量方法技术已经深入到各行各业。它融入了各个学科的能源技术，成为了一门综合性的现代测量技术学科。实现了高精度测量，及微小物体测量。

本设计主要以一个方形工件为实例进行视觉测量，并且通过图像灰度化、二值化以及图像边缘检测来获取物体的实际尺寸。着重深入研究图像处理，并以图像标定和图像处理为主。同时本文详细论述基于视觉的零件尺寸测量技术的应用，并侧重于图像处理的计算过程，通过Matlab程序计算与二维图像绘制，实现了基于视觉的零件尺寸在线测量系统。主要研究以下内容：

1、介绍视觉测量的基本意义、现状即以发展空间，确定设计的解决方案，阐述基于视觉的零件尺寸测量技术，对其技术在线测量方案进行理论分析和实验验证，证明它的可行性；

2、分析获取图像的标定技术，采用标准件标定方法并且对整个测量系统标定，通过实验获得的数据进一步验证系统测量的精确度；

3、通过对图像处理算法的分析，利用Matlab程序，实现图像预处理和像素边缘检测。深入分析图像数据处理和亚像素边缘定位技术，提高计算速度和计算精度。

关键词：基于视觉；零件尺寸；图像处理；边缘检测；灰度化

Based on The

Isual Component Size Measurement

ABSTRACT

Parts size measuring based on vision is the main research is to

simulate human visual function to process the image to extract information from

the objective things to understand, eventually acquire data needed for the

actual size. In recent years, based on the visual component size measurement

technology in the field of measurement in recent years the rapid development of

new technology. It is based on the modern optics, the integration of computer,

laser technology, image processing and analysis technology such as modern

science and technology is a body comprehensive measuring technique.

In this paper, we

use part size measurement based on visual method to measure the mechanical

parts of 2 d geometry, through image processing and Matlab programming drawing

two-dimensional curve analysis of mechanical parts processing. Emphatically study the key technology in the process of image

processing and system calibration problems, achieve sub-pixel locating on the

edge of mechanical parts size, further realize high precision of component

size.Parts size measuring based on vision application in part size measurement

is discussed in detail, and focuses on the process of image processing method,

through the Matlab calculation and two-dimensional image rendering, parts size

online measuring system based on vision is achieved. The main

research content below：

1.Introduce the

basic concept of topic, the research background and significance of the

development and the existing problems at home and abroad, clear solutions to

this topic, this paper based on the visual parts dimension measurement

technology, the technology of online measurement scheme wake the theoretical

analysis and experimental verification, to prove the feasibility of it

2.Analysis of

image calibration technology, the use of standard calibration method and the

whole measurement system calibration, data obtained through the experiment to

verify the accuracy of measurement system.

3.Through the analysis of the image processing algorithm, using

Matlab, the realization of image preprocessing and pixel edge detection.In-depth analysis of the image

data processing and the subpixel edge location technology, improve the

calculation speed and calculation accuracy.

Key Word: based on visual; parts size; image processing ;edge detection;gary

目    录

第一章  绪论.............................................................1

1.1基于视觉系统概述 ...................................................1

1.1.1基于视觉系统基本概念..........................................1

1.1.2基于视觉技术的优越性..........................................1

1.1.3基于视觉系统关键技术..........................................2

1.2基于视觉的研究意义..................................................3

1.3基于视觉的国内外发展现状............................................3

第二章  图像采集系统的组成及设计......................................4

2.1系统的组成原理框架结构 .............................................4

2.2系统的光学设备......................................................5

2.2.1硬件设备摄像头的选择..........................................5

2.2.2图像数据采集卡................................................6

2.2.3照明设备......................................................7

第三章  图像处理及尺寸测量方案........................................8

3.1图像处理的概念......................................................8

3.2系统定标............................................................9

3.2.1定标的概念及原理..............................................9

3.2.2成像原理.....................................................10

3.2.3选取恰当的定标方法...........................................10

3.3图像预处理.........................................................12

3.3.1图像的灰度转换...............................................13

3.3.2图像的二值化.................................................14

3.4图像边缘检测.......................................................19

3.4.1图像边缘检测的论述...........................................19

3.4.2 边缘检测的基本算子..........................................19

第四章  方形件的视觉尺寸测量.........................................23

4.1方形件的系统定标...................................................23

4.2方形件的图像处理...................................................23

4.2.1方形件灰度处理...............................................23

4.2.2方形件的二值化处理...........................................24

4.2.3方形件的边缘检测.............................................25

4.3方形件的测量结果...................................................26

第五章  尺寸测量的误差和误差分析.....................................28

5.1误差及误差原由.....................................................28

5.2减少误差的方法.....................................................28

第六章  总结............................................................30

参考文献.................................................................31

附录A....................................................................33

A.1图像灰度化处理程序.................................................33

A.2图像二值化程序.....................................................33

A.3图像一般梯度边缘检测处理程序.......................................34

A.4图像Cany边缘检测程序..............................................35

A.5图像的像素提取.....................................................38

致  谢...................................................................40