平板平面度检测系统的研究与设计

发布时间：2018-04-11 05:24

本文选题：平面度 + C8051F　；参考：《西华大学》2012年硕士论文

【摘要】：随着电子技术的不断发展，平板技术已经越来越多的应用于电子产品之中，平板产品平面的平整度是决定平板产品质量的重要因素。因而国家质量监督检验检疫总局在2005年03月颁布了平板检测相关规程，对平板工作面平面度参数进行统一规范，并规定平面度最大误差及相应平板准确度级别等。本文依据国家计量检定规程，并结合市场实际检测精度指标要求，提出并实现了一种较为经济的平板平面度检测方案，实现在线批量检测。提出了基于混合信号片上系统型单片机C8051F的智能平板平面度检测系统设计方案。系统依据对角线布点评定法则为基准，采用最小条件原则评定方法，利用SOC系统级MCU芯片为采集器智能核心，通过多路电涡流位移传感器，完成对待测平板的数据采集。运用Modbus协议组成工业级232网络，完成与上位机握手通讯。上位机采用LabVIEW开发设计程控界面，结合Access数据库技术，实现待检测平板数据的采集和历史采集信息的查询、管理等操作。本文的主要工作包括以下几个方面： (1)研究平板平面度检测相关评定准则。根据实际检测平面度允许最大误差基准，选择电涡流位移传感器，按照对角线布点评定法则布点测量。对待检测平板选取合适基准平面，并采用12点布点测量，计算所有测量点相对于理想平面的偏差，其最大值与最小值之差即为待测平板平面度。采用对角线法则进行误差评定后，原始测量数据转换为相对于基准平面的数据，按照最小条件原则进行评定，验证平面度测量结果。 (2)提出了以高度集成的SOC系统级MCU芯片为核心的智能采集系统。系统采用传感器采集平板位移信号，利用多路模拟开关切换选通模拟信号输入，通过仪表放大电路进行信号的前端放大。数据采集系统芯片内置模/数转换器ADC，数/模转换器DAC，电压比较器，可编程增益放大器，以及UART通讯接口等，实现单芯片智能采集设计。系统采用Modbus通信协议RTU传输模式实现采集板与PC机通讯，为了防止传送过程中传输错误，系统进行CRC校验整个消息内容。 (3)采用图形化可视软件LabVIEW开发设计平板平面度检测系统上位机程控界面。选通系统采集通道，并采集选通通道零点电压值；配置串口通讯参数，采集选通通道电压数据，并依据采集电压值转换为相应检测值；设定平板检测合格判据，，并判断平板平面度合格状态，多次采集，进行检测数据统计；调用Access数据库，存储实时检测数据，并可查询历史检测平板合格情况，查询指定日期测试平板数据，对已测数据进行删除、打印等操作处理；设计用户登录及密码修改界面，增强检测系统安全性。 (4)根据平板平面度检测系统需完成功能进行测试。构建函数发生器、六位半数字多用表、PCI-GPIB接口控制器的自动精度校准系统，提高了测量准确度。利用Agilent33220A函数发生器模拟12路电涡流位移传感器产生电位对应电压信号，采用本检测系统采集零点电压值和模拟平板检测电压值，验证检测合格指示状态。按要求查询历史检测数据，检测系统数据库管理功能。测试过程的顺利进行，保证了整个检测系统的正常工作运行。目前平板电子产品飞速发展，人们对其质量的检测工作也越来越为重视，介于实际检测成本和精度的需求，本系统设计不仅性价比高，而且具有完善的数据库管理等功能，目前已在平板平面度检测线上得到成功应用。
[Abstract]:With the development of electronic technology , flat panel technology has become more and more applicable to electronic products . The flatness of flat panel products is an important factor to determine the quality of flat panel products .

This paper presents a design scheme of the intelligent flat - plate flatness detection system based on the system - type single - chip - based on mixed signal chip . The system is based on the principle of diagonal layout . The system is based on the principle of minimum condition principle . The SOC system - level MCU chip is used as the intelligent core of the collector . By means of the Modbus protocol , the data acquisition of the flat plate is completed . By using the Modbus protocol to form the industrial - level 232 network , the communication with the upper computer is completed . The upper computer uses the LabVIEW to develop the program - controlled interface , and realizes the query , management and other operations of the data acquisition and history collection of the flat data to be detected .

The main work of this paper includes the following aspects :

( 1 ) To study the relevant evaluation criterion of flatness detection of flat plate . Based on the actual detection flatness , the maximum error criterion is selected , the electric eddy current displacement sensor is selected , and the deviation of all measuring points with respect to the ideal plane is calculated according to the difference between the maximum value and the minimum value according to the difference between the maximum value and the minimum value . After the error evaluation is performed by using the diagonal rule , the original measurement data is converted into the data relative to the reference plane , and the flatness measurement result is verified according to the minimum condition principle .

( 2 ) The intelligent acquisition system based on highly integrated SOC system level MCU chip is proposed . The system adopts the sensor to acquire the plate displacement signal , and switches the analog signal input through the multi - way analog switch , amplifies the front end of the signal through the instrument amplifying circuit . The system realizes the single chip intelligent acquisition design by using the Modbus communication protocol RTU transmission mode to realize the communication between the acquisition board and the PC . In order to prevent the transmission error during the transmission process , the system performs the CRC check of the whole message content .

( 3 ) developing the program control interface of the upper computer of the flat - plate flatness detection system by adopting a graphical visual software LabVIEW ;
configuring serial port communication parameters , collecting gated channel voltage data , and converting into corresponding detection values according to the acquired voltage values ;
setting a plate detection eligibility criterion , judging the flatness of the flat plate to be qualified , collecting repeatedly for multiple times , and performing detection data statistics ;
calling an Access database , storing the real - time detection data , and inquiring history detection plate conformity , inquiring the appointed day test plate data , deleting the measured data , printing and the like ;
The user login and password modification interface are designed to enhance the security of the detection system .

( 4 ) The function test system needs to be tested according to the flatness detection system of the flat plate . The automatic precision calibration system of the function generator , the six - bit semi - digital multi - purpose table and the PCI interface controller is constructed , and the measurement accuracy is improved . The detection system is used for simulating 12 paths of electric eddy current displacement sensors to generate potential corresponding voltage signals . The detection system collects the zero voltage value and the analog flat panel detection voltage value , and verifies the test pass indication state . According to the requirement , the history detection data is inquired , and the database management function of the system is detected .

At present , flat - plate electronic products are rapidly developing , and people pay more and more attention to the detection of their quality . The system is not only cost - effective , but also has perfect database management functions , and has been successfully applied on the flat - level detection line .

【学位授予单位】：西华大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP274;TP368.12

【参考文献】