【作者】 王永兴；

【导师】 陈辉；

【作者基本信息】 武汉理工大学 ， 轮机工程， 2011， 硕士

【摘要】 随着计算机和系统集成电路技术的不断发展,分布式控制系统正逐步普遍应用于船舶工业当中。但是由于分布式控制系统设备种类繁多,协议不尽相同,所以给数据的传输和集中管理带来了不小的困难。现场总线作为底层的一种拓扑性网络,可以创建一个双向通信、全数字化的控制系统。它可以使现场的多个设备之间以及现场设备与远程监控计算机进行连接,实现数据传输和信息交换。所以我们需要一个规范化的系统,它可以将底层设备的数据采集系统融合在一起,具有良好的传输性能,并可以实现实时监测和事务调度功能。本文在探讨总线技术的基础上,应用CAN总线技术对船舶中的多协议转换及传输机制进行了研究。第一部分介绍了论文的研究目的和意义以及本文的内容和结构框架。第二部分在CAN总线的基础上分析了其应用层CANopen协议的技术规范,对CANopen协议各通信对象的实现进行了初步的探讨,为以后的实现奠定了基础。第三部分首先利用双冗余网络结构设计对CAN总线的实时性、可靠性以及经济性做了优化,然后是RS232/485到CAN总线的协议转换。第四部分对CANopen主站进行了设计,包括CANopen协议的传输机制与接收处理,事务调度算法和定时复合机制策略在总线中的实现。第五部分是结论与展望。在研究过程中,首先解决了底层设备的协议转换,然后在CANopen高级协议的基础上,对网络拓扑及传输机制进行分析,最后是CANopen主站中的各种通信对象(NMT、PDO、SOD、SYNC)的传输实现。在系统的研究设计中,软硬件设计都采用了模块化的思想,在保证系统可靠性和稳定性的前提下,尽可能地减少硬件的设计成本。系统软件设计均采用的是C++语言编写,通信模块以C++通用类的方式提供给应用类去调用,应用中只需要在包含通信类文件的基础上简单地创建实例即可实现基本的CANopen通信功能。利用面向对象设计的方法大大提高了系统软件的可扩展性和可移植性。更多还原

【Abstract】 Distributed control systems are widely and gradually used in shipbuilding industry with the computer and the development of integrated circuit technology systems. However, because of a wide range of distributed control system equipment and the different protocols, there are many difficulties in the data transmission and centralized management. As the underlying topology of a network, filed bus can create a two-way communication, all-digital control system. It can make the site between multiple devices and on-site equipment link with remote monitoring computer, achieve the purpose for data transfer and information exchange. So we need a standardized system, which can make the data acquisition systems of underlying device mix together and possess good transmission performance. Moreover, it should achieve the function of real-time monitoring and transaction scheduling.This article carries on the research of the multi-protocol conversion and transport mechanism in ship, based on the probe of CAN-bus. The first part describes the purpose and significance of the research papers, as well as the content and structure of this framework. The second part analyzes the technical specifications of the application layer of CAN-bus (CANopen) based on the CAN-bus, carry out the preliminary study of the realization of communication objects in the CANopen for the future implementation. The third part first optimize the real time, reliability and economy of CAN-bus, using the double redundancy design, and then design the conversion between CAN bus protocol and RS232/485. The fourth section describes design of the master station, including the transmission mechanism and receiving treatment of CANopen protocol, the realization of transaction scheduling algorithms and high multi-use of resolution timer in bus. The fifth part of the paper is the conclusion and outlook.In the course of the study, first, it solved the point of the underlying protocol conversion, and then analysis the network topology and transmission mechanisms based on CANopen, finally, the realization of communication objects (NMT, PDO, SOD, SYNC) in embedded system of slave and master. The modular plan was being used in the design of software and hardware, in the premise of ensuring reliability and stability of system, as far as possible to reduce hardware design cost. The preparation of system software program used C++ language, communication module presents as C++ general class which is called by the application class, the application has to only include the communication class file to complete basic CANopen communication function. The Object-oriented design improved the system software’s scalability and portability greatly.更多还原