A Design Of Vehicle Data Acquisition System Based On OBD Proprietary Protocol Chip

With the development of science and technology,the society is developing towards the direction of high technology and high intelligence.The automobile industry is developing and changing which makes the structure of automotive electronic control system become more and more complex.The car has become an indispensable means of transport for people to travel,it is not limited to driving cars simply,the more is to understand the parameters of performance of the car,and the car data acquisition becomes one of the important links.According to the principle of vehicle data acquisition,a general performance acquisition system is designed.The data acquisition system is designed and implemented based on the proprietary protocol chip.It can communicate with the automobile On-Board Diagnostic systems through the general diagnosis interface of the automobile,so as to realize the data acquisition of each sensor.In order to implement this system,the main research contents of this paper are as follows:1?Focus on the process of data acquisition by OBD system.Firstly,study the working principle of auto proprietary communication protocol chip ELM327,starting from the chip with the working principle of automobile universal OBD interface pin functions,complete the hardware circuit of automobile data acquisition system design based on the chip module.Secondly,this paper focuses on the theory of data transmission between three kinds of vehicle communication standard protocols.According to the different data transmission modes,the paper designs a more general automobile data acquisition hardware circuit system.2?The key technologies involved in the system are studied.First of all,the bluetooth technology and its communication principle are studied.According to the working principle,the bluetooth communication module and ELM327 chip are designed and implemented.Secondly,the paper studies the operation of the sqlite database under linux,which can use the database operation function to insert data into the database file of linux system.3?I have studied the software development process of the system.Through the research and study of the program development under linux and the development and transplantation of C++ program under android system,the paper designs and implements a general data acquisition software system based on ELM327 protocol conversion chip.The system can collect most of sensor data of the car,and the collected data is saved to a local database file to facilitate the day after the car performance parameters and Research on vehicle fault information.