Study On The Real-time Monitoring And Control Technologies For Vehicle CAN Network

With the increasing of the number of automotive electronic systems, traditional point-to-point method of message exchange does not satisfy communication demand of auotomotive inner distributed real-time control system any more. The raising of the number of electronic systems increases the difficulty of automotive inner wiring, and the weight and cost of automotives. Automotive network came out under this background. At the beginning of 1980's, a Germeny company, Robert Bosch, developed CAN (Controller Area Network) bus communication protocol, which is a high-speed, real-time control protocol, with communication velocity upto 1Mbps, theoretically. It is the unique automotive network protocol approved as an international standard. Nowadays, CAN is extensively used in automotive industry, aerospace industry, etc., and is one of most widespread bus in application.The CAN protocol only defines the Physical Layer and Data Link Layer, and the users may define Application Layer according to their different demands. Hence, concerning different Applycation Layer, it have different explanations on the data from Data Link Layer; in the domain of CAN interface design, it have different type of CAN bus interface cards from different manufacturers. The study contents of this paper is proposed under this background, and its goal is to provide a unified interface for application, and to add a Protocol Conversion Layer for different applications on top of the Data Link Layer of CAN protocol.The title of this paper is "Study on the Real-time Monitoring and Control Technologies for Vehicle CAN Network." The paper includes two aspects: firstly, capsulating different type of CAN bus interface cards from diverse manufacturers, providing an unified interface for its upper application layer, namely, the development of CAN bus communication component,its goal is to decrease the coupling between application and interface card, to increase the compatibility,reuseability and robust of the software. Secondly, adding a Protocol Conversion Layer on its Data Link Layer, which functions as a data semantic conversion between the Monitoring & Control Software and the vehicle CAN network. For better effect of monitoring and control of the vechile operational information, such as the velocity, engine speed, various temperatures, acceleration, etc., corresponding Monitoring & Control Software for vehicle CAN network is necessary. Furthermore, this Protocol Conversion Layer provides a friendly interface for re-development purpose, which reduces the knowledge requirements on CAN protocol for the re-developer and allows the re-developer to build their application based on our reusable components. In this paper, the CAN communication component has been developed and meets the functional requirement of application, and the Monitoring & Control Software implements the real-time monitoring and control of vehicle CAN network effectively. The work reported in this paper has important meaning for AMT production and increases independent development ability of demestic vehicle network monitoring & control software.