Ajax Technology-based Process Control Design And Development Of Remote Experiment System

The remote process control experimental system is possible to be realized with the development of computer network technology and the remote process control technology. In the traditional structure of browser/ server, the data interact between the client and the server is based on the HTTP model protocol Request-Response mechanism, using synchronous data requests, so that the operating efficiency and real-time of browser/ server monitoring system are limited greatly.On the basis of the original process-controlling equipments, a remote process control experimental system based in AJAX technology is developed in the paper. AJAX technology is used to achieve asynchronous data communication mechanisms between the browser client and server. In order to improve the system scalability, server-side uses XML data format. The client obtains datas from the server using asynchronous mode and then displays the real-time curve in FusionCharts.The system consists of three components: remote client, server, local monitor. The custom arithmetic experiment is realized in the remote process control experimental system by using algorithm interface and DLL in the local monitor. Openness and flexibility are improved in the experiment system. Real-time video transmission is realized by using a video transport protocol-RTP in the video surveillance system.At present this system has been applied to the process control technology and system. It was used in real-time and remote monitor to control six process controlling experimental facilities such as, pressure, liquid-level, temperature/flux. A example of flux control is presented to be exploited remote step response identification experiment, remote PID control experiment and custom arithmetic experiment. The results of the experiments demonstrate the characters of the system such as real-time, dynamic behavior and cross-platform, and provide the anticipated platform.