基于机器视觉的数码管显示单元缺陷检测系统  

A Defect Detection System of Nixie Tube Display Unit Based on Machine Vision

作　　者：崔颖 王红英 樊维涛 郭俊丽 CUI Ying;WANG Hong-ying;FAN Wei-tao;GUO Jun-li(School of Mechanical and Materials Engineering,Xi’an University,Xi’an 710065,China;Xi’an Herch Photoelectric Technology Co.,Ltd,Xi’an 710077,China)

机构地区：[1]西安文理学院机械与材料工程学院,西安710065 [2]西安市和其光电科技股份有限公司,西安710077

出　　处：《西安文理学院学报（自然科学版）》2023年第1期51-58,共8页Journal of Xi’an University(Natural Science Edition)

基　　金：西安市科技计划项目-科技创新人才服务企业项目(2020KJRC0105);西安市科技计划项目-西安市创新能力强基计划-先进制造业技术攻关项目(21XJZZ0064)。

摘　　要：介绍了通过机器视觉和OCR识别方法来判断测温仪上LED数码管的工作状态的缺陷检测系统,以提高产品的质量,减轻质检人员负担.系统主要采用机器视觉识别出的LED字符与系统发出的命令字相对照的方法实现缺陷检测.首先通过CRC-16算法生成各个仪器的命令字,然后通过RS485总线分别向仪器发送显示字符命令,通过红色滤光片采用机器视觉采集LED图像,并对图像进行二值法处理、“闭”运算、腐蚀运算.在OCR识别中使用扩大训练字符集及大范围识别参数调整的方法,解决了LED数码管在OCR识别过程中遇到的断码、小数点误判及字符变形、变小问题.系统在投运后运行可靠,稳定,OCR识别误码率小于万分之五.In this paper,a defect detection system is introduced to judge the working state of LED digital tubes by using of thermometers through machine vision and OCR identification methods,so as to improve product quality and reduce the burden of quality inspectors.The system mainly adopts the method of comparing the LED characters recognized by machine vision with the command words issued by the system to realize defect detection.Firstly,the command word of each instrument is generated by CRC-16 algorithm.Then,the display character command is sent to the instrument through RS485 bus,and the LED image is collected with machine vision through red filter,and binary processing,"close"operation and corrosion operation on the image are performed.In OCR recognition,the method of expanding the training character set and adjusting the recognition parameters in a large range is used to solve the problems of broken code,misjudgment of decimal point,character deformation and reduction encountered by LED nixie tubes in OCR recognition.The system operates reliably and stably after being put into operation,and the OCR identification error rate is less than 5/10000.

关 键 词：机器视觉 OCR LED数码管 闭运算 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]