Development Of Vehicle Data Acquisition And Information Interactive Terminal Based On CAN And OBD-Ⅱ

In the face of increasingly serious traffic safety and traffic congestion,the research on the network of automobiles has been put on the agenda.The Internet of Vehicles aims to effectively connect people-car-roads and clouds through the network to realize mutual information interaction,thereby solving potential traffic problems and improving the convenience of the owner’s driving.As the basis of all application scenarios of the Internet of Vehicles,it is of great significance to study how to collect,store,transmit and analyze data safely and efficiently.Based on the above knowledge,this paper takes the industrial-grade control chip STM32 as the core,and under the guidance of GBT 32960 national vehicle terminal specification,it combines the vehicle bus technology,wireless communication technology,GPS global positioning technology,digital encryption technology,etc.to develop vehicle data collecting and information interacting terminals.At the same time,cloud applications based on Alibaba Cloud ECS server and China Mobile IoT open platform were developed.It mainly includes the following contents:Firstly,this paper analyzes the advantages and disadvantages of the existing schemes of on-board data acquisition systems at home and abroad,and explores the principles and characteristics of key technologies such as automotive CAN bus,OBD interface,GPS,4G,Bluetooth,etc.Under the guidance of the national standard GBT 32960,the vehicle data acquisition and information interaction system architecture is designed.Secondly,in terms of hardware,based on STM32F103C8T6 and other chips,the hardware circuit and physical object of the CAN data acquisition and fault diagnosis equipment for the computer are developed.Based on the STM32F103RET6 and WHG405 tf chips,the hardware circuit and physical object of the data acquisition and interaction terminal for mobile phones and clouds are developed.The development of the PCB board was completed using Altium Designer 13.In terms of software,GPS information and driving information collection functions,OTA remote upgrade function based on FTP protocol,and vehicle remote control functions based on protocols such as Bluetooth,TCP,and HTTP were developed,and AES advanced symmetric encryption algorithm combined with BASE64 encoding was used to encrypt the relevant data.Once again,cloud applications were developed on the Alibaba Cloud ECS platform and the Onenet IoT platform.The FTP server is built;the cloud parsing,storage and display functions of the driving data are realized;and the instruction information such as the warning and the control can be sent to the vehicle terminal to realize the cloud-vehicle interaction.Finally,the test scheme was designed,and several test aids such as CANtest were developed.The functions of data acquisition,encryption,transmission and remote upgrade of the vehicle terminal were tested in the indoor and real vehicle environments,and the reliability of the system was verified.