CAN总线在嵌入式磨削数控系统中的研究与设计

【作者】 张健；

【导师】 蒋新华；

【作者基本信息】 中南大学 ， 控制科学与工程， 2008， 硕士

【摘要】 数控系统是计算机技术在机械制造领域的一种典型应用,它集计算机、机械加工、微电子和自动控制多项技术于一体。数控技术的应用不仅给传统的制造业带来了革命性的变化,而且对国计民生的一些行业的发展也起着越来越重要的作用。目前,随着嵌入式系统的不断发展,由ARM微处理器构成的嵌入式系统以其低成本、高可靠性、高稳定性,在机床数控领域得到了越来越广泛的应用。数控系统的通信设计对整个数控系统功能的实现有着重要的影响。因此,研究数控系统的通信总线对提高数控系统的效率和稳定性有着积极的作用。作者在基于ARM9的嵌入式数控磨削系统中,在对比和研究了当今应用最为广泛且具有一定的开放性和标准化的现场总线—基金会现场总线FF、Profibus总线、CAN总线等的技术特点和应用性的基础上,最终选择了CAN总线作为系统的开放式总线。基于ARM9嵌入式数控磨削系统的硬件结构的设计是采用主从式的多微处理器结构模式。主微处理器S3C2410负责对键盘、LED数码管、液晶显示器进行控制,从微处理器通过FPGA控制X、Y、Z、A、B、C轴的运动,或者接收来自外部的各种开关量、模拟量和数字量信号。各节点处理器通过各自的SPI接口与CAN控制器MCP2515相接,再通过CAN收发器MCP2551接入到CAN总线,实现了主从处理器各节点间的通信。作者在当今应用非常广泛的嵌入式操作系统Linux+RTAI的软件平台下,通过对数控系统软件功能的分析,借助CAN总线完成了数控系统上下位机插补数据传输、上位机对下位机节点的实时监控以及上位机对输入输出节点的控制软件的设计。更多还原

【Abstract】 NC system is a common application of computer technology in machine building industry. It is integrated by computer technology, mechanical processing technology, microelectronics technology, automatic control technology. The application of NC technology not only has brought about radical change for traditional building industry, but also will play a more and more important role in development of some industries of our country .At present, with the development of embedded system, Embedded system based on ARM technology has been widely used in NC machine tool field because of its low cost, high reliability and stability.Communication design of the entire NC system has an important impact on the realization of system’s function. Therefore, recearch on the NC system communication bus has a positive role to improve the efficiency of NC and stability.The hardware circuit structure of embedded NC grinding system is designed based on ARM9. This is a structure of master-slave mode and a few microprocessors. The master microprocessor S3C2410 deals with input task of the keyboard and output task of LED and LCD. The slave microprocessors control the movement of four axises or receive the exterior signals, such as switching signal, analog signal, digital signal. Each node microprocessor connect MCP2515 CAN controller by own SPI interface, and then connect CAN bus through PCA82C251 CAN transceiver, communication among node microprocessors is set up.This paper is widely used in today’s embedded operating system Linux + RTAI software platform, through the NC system software analysis, with the completion of the NC CAN bus , system realize the data transmission from top to bottom-interpolation, the real-time monitoring and control of the PLC software design.更多还原