Design Of Combustible Gas Leakage Monitoring System Based On Wireless Sensor Network

The chemical industry is the lifeblood of economy development of ourcountry. The application scale of toxic and hazardous chemicals in the chemicalindustry is gradually expanding. Out of the concern about safety production andcontinuous progress of various information technologies, the monitoring for toxicand hazardous chemical materials has also realized informationization andnetworking. Many types of combustible gas can be explosive and toxic. Itsleakage will be a threat personal safety and causing significant property loss. Inthis paper, combined with the relevant national industry requirements and actualproduction needs, combustible gas leakage monitoring system based on wirelesssensor network is designed based on the analysis of combustible gas detectiontechnology and the development of wireless sensor network (WSN).In this paper, the star network topology is built with the ZigBee self-organized network as wireless communication core architecture. The simple andpractical communication protocols are designed and they are optimized by usingsynchronous dormancy mechanism. The central node is built as data transmissionintermediary connecting monitoring terminals with upper monitoring interface,which is designed by using enhanced ZigBee module. A friendly interactiveinterface is developed at VB6.0platform. It also can actualize many functions,such as real-time monitoring of environmental parameters of monitoring locale,alarm of combustible gas concentration beyond the threshold, drawing dynamiccurve, historical data query, and so on.In the design of hardware, MSP430F149SCM is as the core processor.Sensor monitoring terminals and the central node are designed. Monitoringprobes of monitoring terminals adopt catalytic combustion type gas sensors, and relevant amplifying transmitter circuit is designed with them. The terminal alsohas display and alarm function. Underlying drivers of terminal are developed atIAR platform. They are embedded concentration fitting algorithm, and improvethe accuracy of monitoring data of the monitoring terminal.Prototypes are calibrated after design completion. Then they are carried outenvironmental experiments for some parameters, such as zero drift, systematicerror, response time, communication distance, packet loss rate. Finally, thecommunication network function test is carried out.The practical tests show that the networking ability of the system ispowerful and the working is reliable. The system can satisfy norms of relevantnational industry of combustible gas leakage monitoring. Optimizedcommunication protocols reduce system power consumption. Modular designenhances the flexibility and the scalability of the system. This system satisfiesthe design requirements and has good scientific values and market prospects.