一种AD7190电桥电压数据采集系统的设计  

Design of bridge voltage data acquisition system based on AD7190

作　　者：黄永庆 周信健 陈龙权 玉振明 HUANG Yongqing;ZHOU Xinjian;CHEN Longquan;YU Zhenming(Guangxi Key Laboratory of Machine Vision and Intelligent Control,Wuzhou 543002,China;School of Electronics and Information engineering,Wuzhou University,Wuzhou 543002,China;Guangxi Engineering Technology Research Center of Intelligent Microscope Equipment,Wuzhou 543002,China)

机构地区：[1]广西机器视觉与智能控制重点实验室,广西梧州543002 [2]梧州学院电子与信息工程学院,广西梧州543002 [3]广西智能显微设备工程技术研究中心,广西梧州543002

出　　处：《现代电子技术》2023年第4期45-51,共7页Modern Electronics Technique

基　　金：广西科技计划项目桂科(AD20297148);梧州市科技开发项目(201902041);梧州学院校级科研项目(2018B009)资助。

摘　　要：在研究压力、拉力等电桥式传感器输出变化情况过程中,必须要对其过程数据进行采集和记录,用于系统分析。文中利用AD7190及STM32F103设计一种电桥电压采集系统,通过MAX6350产生稳定的5 V电压基准,经过缓冲功率放大后接到电桥的激励端给电桥供电。在电桥的输出端使用AD7190模拟前端芯片对信号进行放大和模数变换;然后由STM32读取转换结果并对数据进行滑动均值滤波、工程单位变换、数据四舍五入以及端口输出控制比较等;最后使用free ModBus的ModBus RTU协议,通过RS 485接口在MCGS人机界面上显示数据和控制,并通过RS 232串口或USB虚拟串口发送采样的实时数据到计算机进行数据记录。实验测试结果表明:所设计系统在300 Hz采样率下,每分钟记录数据量约为200 KB,使用磁盘容量大的计算机可以进行长时间数据记录;电压数据相对误差在0.28%以内,稳定性较好,能满足一般电桥数据采集的要求。In the process of studying the output changes of pressure,tension and other bridge sensors,the data in the change process must be collected and recorded for system analysis. A bridge voltage acquisition system is designed by means of AD7190 and STM32F103. The stable 5 V voltage reference is generated by the MAX6350, and after the buffer power amplification,it is connected to the excitation terminal of the bridge to supply power to the bridge. The AD7190 analog frontend chip is used at the output end of the bridge to amplify signal and conduct the analog-to-digital conversion. The STM32 can be used to read the conversion results and perform sliding mean filtering,engineering unit conversion,data rounding and port output control comparison of the data. The ModBus RTU protocol of free ModBus is used to display data and control it on the MCGS human-machine interface through RS 485 interface,and send the sampled real-time data to the computer for data recording by means of RS 232 serial port or USB virtual serial port. The testing results show that,under the 300 Hz sampling rate,the designed system can record data about 200 KB/min,and can record data for a long time by the computer with large disk capacity. Its relative error of voltage data is within 0.28%,and its stability is good. The system can meet the requirements of general bridge data acquisition.

关 键 词：电桥电压采集 数据记录 AD7190 数据发送 数据传输 信号放大 模数变换 

分 类 号：TN722-34[电子电信—电路与系统] TH85[机械工程—仪器科学与技术] TP216[机械工程—精密仪器及机械] TM933[自动化与计算机技术—检测技术与自动化装置]