Can Bus Technology And Its Application In The Torpedo Guidance System

This thesis mainly deals with the open torpedo guidance system based on bus technology and information synthesis. Firstly the controller area network (CAN) technologies of hardware and software, real-time ability, application-layer protocol are presented. Two CAN bus controllers, SJA1000 and eCAN module, are introduced with their traits, applications and design of three basic CAN communication program modules including system initialization, message-receiving and message-sending. The real-time performance of CAN is studied. This thesis classifies the time delay of messages on CAN bus into four kinds, and gives them respective mathematics models. Methods how to improve the real-time ability of CAN are also discussed.Then the time-triggered CAN (TTCAN) protocol is analyzed, involving synchronization mechanism, time types, system matrix, mechanism of error monitoring and disposing, real-time ability and so on. In contrast with CAN, the thesis points out the improvement and shortcomings of TTCAN and migration from CAN to TTCAN. Moreover, the application of TTCAN in torpedo guidance system is discussed.Finally, the torpedo guidance system based on CAN is studied. This new type of guidance system based on bus, which is completely different from current one, is a trend of digital and intelligent torpedo weapon. A principle prototype in the laboratory is designed, comprising four nodes: a PC node, a PC/104 node, a DSP (TMS320F2812) node and a microcontroller (P89C52) node. And the correlated application-layer protocol of CAN is constituted. The principle prototype completes the experimentation of torpedo depth control successfully. It confirms that the CAN bus will be competent for torpedo guidance system.