The Design And Realization Of On-board Video Monitoring Terminal With ARM9-based Embedded Processor

The healthy development of the transportation industry is the foundation of the steady of the national economy, and public transportation occupies an extremely important status in transportation industry. Public transportation safety and efficient operation is one of the key factors influencing the economic development. In recent years, in view of the frequent occurrences of violence in bus, not only caused enormous losses to people’s lives and property safety, but also has a negative impact for social stability. With the progress of information technology, the government and public transport enterprise is becoming more and more urgent to the demand of public traffic vehicle on safety regulation. Using modern information technology realize the real-time monitoring and management to the operation vehicles, the event of emergency disposal and the traffic evidence storage. It is the important measure of promoting the construction of public traffic safety.This paper proposes a design scheme of on-board video monitor terminal, and focusing on human-computer interaction module, communication module, positioning module and video module. Firstly, this paper introduces the research background and current situation, the purpose and significance of the project. Then briefly described the main functions and hardware design of on-board video monitoring terminal, including the overall design of the hardware and the division of function modules. It discussed focusing on the hard-disk damping structure of on-board environment. In this paper, the on-board video monitoring terminal contains two subsystem, including public transportation service subsystem and video monitoring subsystem, the man-machine UI, positioning module, communication module and video monitoring are core content and also the focus of this paper.In the part of the core software module, man-machine UI is firstly illustrated. Man-machine UI as a channel of communication between the user and the terminal, including touch screen unit and interface unit. Touch screen units need deal with input information from touch screen and buttons, and linkage with the software function. User interface (UI) design including the hierarchical structure of the menus, as well as the main business interface general design. Secondly, the design of positioning module and communication module was introduced. The communication module and positioning module is the overall foundation of on-board video monitoring terminal for normal operation. This article firstly illustrate the design flow of the communication module, including hardware initialization, data transceiver and replacement process, and design for many operators, various hardware chips in object-oriented operating model. Then problem of the static and dynamic drift are analyzed when the satellite positioning chip in daily use. This paper has carried on the targeted optimization design, can effectively improve the drift problem for the influence of the positioning accuracy. Finally, the video storage module is discussed in detail. In daily, On-board video monitoring power on and power off with the random time, data easy to be destroyed such as fragments. In this section, the storage device of on-board video monitoring terminal is customized partition and customized file system design, can completely solve the problem of video data fragmentation, improving the efficiency of reading and writing. Then the video index and storage data structure is discussed. Through the design of data structure can realize the rapid retrieval and efficient storage of data. According to the reliability of the on-board video monitor with specific design, including video double storage function and video integrity detection function. According to this section, it can meet the running conditions of on-board video monitoring and provide reliable support for the daily supervision and investigation.At the end of the paper, the on-board video monitoring terminal testing and evaluation was completed. Firstly, the professional testing in the three direction of vibration in X, Y, Z axis. Then the positioning accuracy of static and dynamic simulation is tested. At last, video storage capability of the equipment is tested in laboratory and commissioning tests at the scene. After testing, the experimental results meet the design goals.This topic research of on-board video monitoring terminal has marketed in dozens of cities in domestic. It provided important support for the daily supervision and administration of transport enterprises and the public security department for many disputes, public security, incidences of terror and violence.