Research On Multi-purpose Vehicle Travelling Data Recorder

Because of the rapid development of transportation industry, ensuring driving safety has become important guarantee in daily life. Affairs just like accident cause analysis and responsibility perspicuity in traffic accident deposing need support of technological means more and more. Vehicle traveling data recorder is the electronic instruments that can real-time collect and record traveling state, help related personnel analyze causes of traffic accident and definite responsibility.Though recorders in the market have possessed basic functions, most of them don't integrate GSM wireless communication and voice alarm module, also can not remote monitoring vehicle state in real-time. According to stipulated by national standard and applications of vehicle traveling data recorder, a real-time system which takes ATmegal28L as the core and has the ability of collecting, processing, storing and communicating. The single chip ATmegal28L has integrated ADC, standard serial interface and SPI interface that simplified peripheral circuit. Real-time clock PCF8563 is adopted, large capacity serial flash AT45DB321 as the storage medium, can monitor and record vehicle traveling state in real-time; Recorded data can be uploaded to host computer in order to daily manage and accident diagnosis, also connected to GSM to remote monitor vehicle state. CH375 produced by Nanjing QinHeng Electronics Co. ,Ltd. is used to USB module that provides convenient man-machine interface. Voice alarm circuit ISD1730 is selected to alert over-speed and timeout to warn the drivers" violations.Development process of vehicle traveling data recorder has been presented briefly, basic functions and develop method are explained. Characteristics of AVR single chip ATmegal28L are introduced. According to technical requirements and functional characteristics, overall design and hardware scheme is determined. The overall hardware system can be divided into nine pieces: single chip minimum system, analog and switch signal sampling module, real-time clock, data storage, voice alarm, RS232 communication, USB interface, GSM wireless communication, key-press and display module. On the basis, hardware and software development process are described in detail. The results showed that, through hardware and software of system debugging, performances of the vehicle traveling data recorder that designed were stable, the indexes met with technical requirements basically.