Research On CAN Bus Control System Of Commercial Vehicle Body Based On SAE J1939

The rapid development of automotive electronics technology makes the number of body controllers increased significantly.In the body control system with traditional point-to-point communication,the increase of the controller will lead to the increase of the signal line and the power supply line,which will not only bring difficulties for the wiring harness wiring and the fault diagnosis,but also bring instability to the signal control.The emergence of the controller LAN-CAN provides the possibility to solve the above problem.CAN bus with its fast communication rate and excellent anti-jamming capability in domestic and foreign passenger cars widely used to improve the reliability of vehicle control.At present,the use of SAE J1939 protocol distributed CAN bus control system has been widely used in foreign commercial vehicles.Aiming at the widespread use of centralized and decentralized vehicle body control in domestic commercial vehicles,this paper designs a distributed vehicle CAN bus control system based on SAE J1939 protocol on the basis of deeply analyzing the application of CAN bus at home and abroad.The main research contents are as follows:(1)Through the testing and analysis of the electrical system of a heavy truck,the shortcomings of the traditional decentralized body control system connected by the harness connection are pointed out,and a distributed body control scheme based on the bus connection is proposed.(2)The V-type development process commonly used in the development of vehicle network is described.According to the requirements of vehicle body control,the control module,the front control module,the left door module,the right door module,the instrument module and the rear control module A total of six nodes of the pin control requirements;based on SAE J1939 protocol developed between the various modules of the application layer communication protocol,generated eight different ID of the message and the development of the module between the CAN communication matrix.(3)Modeling the body control system with six modules using CANoe software: establishing DBC database file based on CANdb ++,designing the interactive panel based on panel,and writing the software program based on CAPL language.Through the simulation and analysis of the bus network,the results show that the design of the vehicle CAN network performance to meet the requirements.(4)Altium Designer software is used to design the main hardware circuit of each module.At the same time,CodeWarrior is used to write the software program of each module.The correctness of the program is verified by online compilation and debugging.(5)Using RIGOL oscilloscope,CANalyst analyzer and other tools to build the body CAN bus control system to test the main functions,including CAN communication test and load drive test.The test results show that the network communication is normal,the bus load rate is low,the message is sent and received correctly,the communication delay meets the requirements;the load drive control is reliable and the response is quick.The research shows that the CAN bus control system based on SAE J1939 protocol realizes the intelligent network of commercial vehicle body control and the fault diagnosis,which provides reference and reference for CAN bus network development of commercial vehicle.