Design And Development Of Vehicle Remote Data Terminal Based On OBD

With the developing of economy and technology,the growth of personal vehicles is growing rapidly,the reliability of the vehicle and the safety requirements are getting higher and higher.Because of increasingly complex automotive equipment and driving environment,we need to better understand the car and monitor the car.In order to develop good driving habits and contribute to the maintenance of vehicles,the vehicle’s various information in real-time must be controlled.The development of mobile Internet takes unprecedented shock to vehicle industry,which makes the combination of vehicle and mobile Internet more and more.Many applications are through OBD(On-Board Diagnostics,car diagnostic system)to interact with the vehicle,and then through the mobile Internet for remote transmission.OBD system is required to equip in order to limit the emission of vehicle exhausts,which can be used to test whether the emission of tail gas is over-proof or not and to perform vehicle fault diagnosis and obtain car travel information.In order to face this situation,this project proposes an OBD based vehicle Remote data terminal.This terminal gets driving information and geographic information in cars.At the meantime,GPRS net uploads information to the server.Make mobile phone client application long-distance connecting to the server.Design and development include software and hardware design and the development of remote server,which solves the problem of driving data getting,faulty taken,information transporting,data saving and displaying.First,using vehicle remote data terminal of STM32F103C8 main control chip connects to the interface of OBD and communicates with each other through sending and receiving CAN message.Then,following the ISO15765 faulty detection communication protocol during communication,we read vehicle driving information and a part of faulty information through this method.The main control chip analyses and gets the real-time longitude and latitude information through using the NMEA—0183 protocol transported by GPS module from U-BLOX chip.Finally,transport the vehicle information and geographic information to GSM networking through GPRS module from the M35 chip.GSM operator network connects to the internet through TCP method,which means transporting data to the long-distance server through mobile network.The functions of receiving and saving data are achieved on the server.Using Socket communication receives the information send from vehicle remote data terminal,and builds connection with the My SQL database.Then the information is saved into the database periodically.Using C based API embedded in i OS mobile phone client application builds long-distance communication,which can achieves long-distance getting and displaying information reflecting the real-time information straightly.Using vehicle and simulation test this system.Utilizing USBCAN-II connects computer and simulate the receiving and sending message through CAN-test software to verify whether the query CAN message transported by vehicle remote data terminal obey the faulty detection communication protocol or not.Finally,using OBD simulator to imitate the reply of CAN message from OBD system in vehicle.The result shows that vehicle information getting is normal and geographic information getting is accurate and the information transporting is reliable,which means the system can achieve long-distance supervising and management to vehicle.So far,the design and development of vehicle Remote data terminal based on OBD is finished.