Design And Implementation Of Vehicle Internet Information Terminal

The rolling forward wheels bring progress to human society, but they also bring us the problems such as traffic jams, traffic accidents, energy depletion and environmental contamination. Among them, the direct economic loss caused by traffic accidents and traffic jams every year is enormous. In order to solve these problems, people had put forward the concept of "intelligent transportation". As a new trend of intelligent transportation, the technology called "internet of vehicles" has been paid more and more attention by experts.The dissertation introduces the present situation of research on vehicles internet at home and abroad, then it describes the involved technologies of vehicle internet information terminal such as on-board diagnosis (OBD), GPRS communication, GPS positioning and speech synthesis. According to the functional requirements of the vehicle internet system, a solution of vehicle terminal has been proposed. Then the hardware and software of a vehicle information terminal system has been designed and implemented. The developed terminal has been tested through the experiment on a electric car, the result shows that the system can realize the functions such as vehicle positioning, navigation, wireless communication, voice scheduling and fault code detection.The developed vehicle terminal mainly includes the following modules:MCU module, power-supply module, GPRS module, GPS module, speech synthesis module, LCD module, CAN module, asynchronous serial interface and so on. The central processor adopts the freescale MCU of9S08series. The MCU is used to collect and process the data from OBD and GPS, and then it will control the GPRS module to communicate with the dispatching center. After receiving the dispatching command from the dispatching center, the MCU will drive the speech synthesis module to complete voice navigation and prompt tasks. The communication between MCU and OBD system is based on CAN, which accords with the design concept of automotive communication network. The vehicle terminal is compatible with24V and12V DC power supply, its power-supply circuit has self-protection functions.The developed vehicle internet system includes information terminal and laboratory dispatching center. The communication between them is based on GPRS. At first a TCP server was built in dispatching center, and then the terminal connects to the server according to the port number and IP address. Through the actual test in the campus, the result shows that the circuit design is reasonable and each module can work normally. The vehicle terminal can basically achieve the goal of design.