Research And Design Of Distributed Electronic Belt Scale Based On AVR Microcontroller

The electronic belt scale is a kind of real-time,dynamic and continuous measuring equipment,which is usually used to measure the flow of material.Based on the calculation of the speed signal and the weight signal,the instantaneous flow rate and cumulative flow of material can be reached.This equipment has a quality of high degree of automation,and can measure material flow when the delivery of the materials is not interrupted.The research of electronic belt scale is very important to the accurate and reliable measurement of material flow.The system is designed from two aspects of hardware and software.Signal acquisition units of the system are distributed reasonably and controlled centrally by the host computer which realizes synchronizing and real-time measuring of multi point.With strong scalability and flexibility,it effectively improves the quantitative,fixed-point,positioning measurement methods of the traditional electronic belt weighing and it also overcomes the issues such as small range of measurement points,the poor real-time synchronization and so on.It particularly applies to the following measurement environments:the tension of the belt is easy to change,the belt is severely off track,the transporting belt is too long.The circuit of the system is developed by using Altium Designer 16,including circuit principle diagram design,circuit simulation and Printed circuit board(PCB)design.By using the high performance ATmega128 microcontroller as the core unit,the crystal oscillator circuit,reset circuit,power circuit,real time clock circuit,digital input circuit,signal amplifying circuit,A/D circuit,D/A circuit,EEPRM data storage circuit,LCD display circuit,keyboard circuit,4-20mA current loop circuit,the system performs the functions of real-time monitoring,feedback,analysis,calculation,processing and so on.The software is designed by using ICCAVR development tools.The content of software design includes:real-time data display,historical data display,speed parameter setting,the range setting,standard time setting,time period setting and starting time setting,historical access records clearing,warning setting,parameter backup and recovery,belt scale zero calibration,flow coefficient calibration,weighing sensor calibration,current output calibration,etc.At the same time,in order to improve the measurement accuracy of the system and restrain the outside interference,in this paper,the digital filtering algorithm is used to correct the results.Finally,based on the actual engineering project of a concentrator,this paper researches a management information system of electronic belt scale based on Java Web Technology.The system connects the electronic belt scale with enterprise management.The whole system is developed by using Eclipse and designed by using MVC mode,B/S structure and three layer architecture.The system server is Tomcat and the database is SQL Server.