【作者】 杨小华；

【导师】 吕新民；

【作者基本信息】 西北农林科技大学 ， 机械设计及理论， 2007， 硕士

【摘要】 随着我国经济的不断发展,人民生活水平的不断提高,现代农业越来越注重种子和粮食的加工质量。因此,清选机械在农业生产中起着越来越重要的作用。在新机械研制和相关研究都需要对工作原理及结构参数进行试验研究,在教学实验和创新中,试验台是必需的设备,要提高实验台的精度,获得准确的数据需要对其进行必要的监控,因此,清选试验台监控系统的研究就成为重要课题。通过对国内外清选机械及自动控制技术的发展现状的分析与比较,提出了针对清选机械的自动控制研究方案;确定了清选试验台监控系统的监控参量:风机转速、气流方向、筛子振动频率及喂入量;设计了以MCS-51系列单片机80C51为控制核心的自动监测与控制系统,配置了以8位逐步逼近型A/D转换器ADC0809、编程I/O口扩展芯片8279、外部数据存储器62256芯片、程序存储器27256芯片、看门狗MAX183L芯片及8位D/A转换器DAC0832及8×8键盘、8位7段LED显示器等部件。设计了监控系统的硬件及软件。系统硬件设计包括了选择硬件,设计接口电路、采样保持电路、放大电路及抗干扰电路;接口电路设计包括了单片机与A/D转换器接口电路、单片机与D/A转换器接口电路、单片机与外部存储器接口电路、键盘、显示电路、报警电路;并设计了看门狗电路以抵抗外界对系统的干扰。系统软件设计部份采用MCS-51系列汇编语言编写了系统流程图及主程序、数据采集和数字滤波子程序、控制子程序、执行子程序、显示子程序。最后,系统采用了MULTISIM 2001 DEMO软件对采样保持电路、放大电路进行了模拟仿真,并采用了MATLAB软件对功能子程序进行校正实验,确定了系统的可行性。清选试验台监控系统的研究与开发,为清选试验台的研究开发提供了支持,对提高试验台的自动化水平,提高实验台性能,获得可靠数据都有着重要的意义和应用价值。更多还原

【Abstract】 Along with our country economy development, the lives of the people level enhancement, the modern agriculture more and more pays great attention to the seed and the grain processing quality.Therefore, the cleaner weapon is playing the more and more vital role in the agricultural production.The principle of work and the design parameter needs conducts the experimental study in the new machinery development and the correlation research. The testing platform is the essential equipment in the teaching experiment and the innovation.Must enhance the laboratory bench the precision, obtains the accurate data to need to carry on the essential monitoring to it, therefore, the research and exploitation of the testing platform monitor system to become the important topic.Compared to the domestic and foreign cleaner weapon and the automatic control technology development,we propose the cleaner weapon automatic control system. The monitoring parameter were choosed in the testing platform monitor system,they include the airflow speed, the airflow direction, the screen vibrate frequency and feed; 80C51 of the MCS-51 series single-chip microcomputer as its core was designed in this paper. 89C51 has EEPROM itself, and shows the merits of high integrated level and strong function. Besides that a double integral A/D converter ICL7109, programming port I/O extended chip 8155, external data memorizer chip6264, Program Memory chip 27512and Watch dog Monitoring Chip X27512 are required to form the Real-Time Monitoring & Control System.The designing of the Single Chip Microcomputer Application System can be divided into two parts: hardware circuit design and software programming. The former is consists of sample circuit design, interface design of A/D converter with Single-chip Computer, single chip microcomputer and design of memory circuit, design of display circuit and design of alarm circuit and watchdog circuit ect. The latter part includes the main program design, subprogram designing of digital filter and interruption subroutine, design of the subroutine for different functions and driving program, subroutine design of display and alarming. System software is programmed in Franklin C51 and assembly language.Finally, a simulation experiment based on MATLAB program and hardware simulation test on part of the circuit were conducted and the results indicate that the system has fine real time monitoring and controlling function.The research and exploitation of the testing platform monitor system have the vital significance and the application value, that provide the support to the research of the testing platform, enhanced the test platform the automated level, enhanced the laboratory bench performance, obtained the reliable data.更多还原