Design Of Commercial Vehicle Signal Simulator And Information Acquisition And Processing System Based On CAN Bus

With the application and promotion of information technology,the integration of electric and networking has become an important development direction of commercial vehicle electronic equipment.At present,there are few on-board electronic monitoring and testing devices for commercial vehicles,which have high cost,poor flexibility and low intelligence.It reduces the convenience of driving and the efficiency of information interaction between vehicles and the outside world,and brings potential traffic safety problems.In view of the above problems,it is of great significance to study how to improve the intelligence of commercial vehicle electronic equipment.Based on the above cognition,the research work of this paper is divided into two parts.The first is to develop an intelligent signal simulator for the electronic control unit test of commercial vehicles.Through this simulator,the simulation signals of each system parameter can be sent to the vehicle CAN network bus,which provides the necessary support tools for the development of subsequent information acquisition and processing systems and other commercial vehicle application systems.The second is to design an information acquisition and processing system that can view the key data of commercial vehicles in real time.Through the system display terminal or mobile terminal,the vehicle running state parameters are viewed to avoid accidents caused by vehicle system failure.Firstly,the overall scheme of the system is designed according to the functional requirements,and the key technologies involved are analyzed and selected according to the scheme.In terms of hardware,both systems choose STM32F103zet6 chip of ST Company as the main MCU.The signal simulator is equipped with TFT-LCD touch screen,LED and TJA1050 CAN transceiver and other peripheral modules.The information acquisition and processing system selects Bluetooth module,LCD display module,EEPROM data storage module and TJA1050 CAN transceiver and other hardware modules.The above circuits and interfaces are analyzed and designed one by one,which lays a hardware foundation for the development of system software.The system embedded program development uses Keil5 platform.In order to develop conveniently,STM32 standard library,μC/OS-III system and SAE J1939 protocol stack are transplanted.In the software part,the commercial protocol stack is firstly lightweight cut,and the application layer is redesigned.The protocol stack compilation time is reduced from 5seconds to 3 seconds after cutting,which provides support for the standardized data processing based on SAE J1939 protocol.Signal simulator software completes the human-computer interaction interface program,touch screen input control program,signal transmission program,dynamic display program and CPU utilization statistics program design,and realizes the mutual cooperation between tasks based on μC/OS-III system.Information collection and processing system completes the data acquisition,forwarding,storage,display program,mobile APP interaction program.The mobile APP monitoring terminal uses MIT app inventor online software programming to complete the Bluetooth connection management and vehicle data reception and display program design.Finally,the human-computer interaction,data transmission and dynamic display of the signal simulator touch screen,and the data acquisition,data forwarding and mobile phone APP data receiving functions of the information acquisition and processing system are tested through simulation experiments,and the information acquisition and processing system is comprehensively verified by the signal simulator.The experimental results show that the system has good stability,real-time and accuracy of data processing,and the performance meets the expectation,which verifies the feasibility of the overall scheme design.