The Design And Realization Of Vehicle Monitoring And Control System Based On Browser/Server

Vehicle monitoring system is a part of intelligent transportation system. Its basic function is real-time vehicle positioning and condition monitoring of vehicles. It costs a lot to develop and deploy traditional vehicle monitoring systems based on C/S (Clint/Server) structure which has poor scalability. By them, users can not access to information quickly and conveniently too. Therefore, the vehicle monitoring system based on B/S (Browser/Server) structure has become the mainstream.With the research and analysis of WebGIS (Web Geographic Information System), Ajax (Asynchronous JavaScript and XML), GIS Web Services and other key technologies, a B/S mode vehicle monitoring system based on Ajax and GIS Web Services is designed to solve problems such as poor system security and complex Client deployment caused by plug-ins usually installed in the browser. The system's principle, architecture and main functions are introduced. Database and main modules, such as real-time monitoring, track intervals, path planning, map matching and coordinate conversion, are designed in detail.According to the system's architecture, the work flows of browser and server are introduced respectively. Ajax engine, the core component of browser, and the GIS Web Services in the server are realized. It has also been analyzed that how map operating and vehicle positioning functions can be realized. All in all, the system functions are implemented by the way that Ajax engine invokes GIS Web Services asynchronously.Experiments show that with unchanged network bandwidth, the vehicle monitoring system based on Ajax and GIS Web Services can reduce the communication between server and browser and can increase the speed of map loading. The technological difficulties of monitoring vehicle on Internet, such as real-time positioning, dynamic tracking, track intervals and shortest path, are solved. This system is valuable in practice.