The Research On Underground Monitoring System For Safety Based On Wireless And Optical Fiber Sensing Hybrid Networks

The coal is a major energy which used in producing and consuming in our country. The development and application of coal is inseparable from social development and people's lives. However, the coal mine accidents are frequently happened in recent years which make the safety of coal production be much attention. The existing mine safety monitoring systems are mostly based on industry bus wired communication transmission networks, so the pipeline extension would be a difficulty with coal mining and excavation. The cable networks can not meet the needs of production safety, so a wireless and optical fiber sensing hybrid network may be an alternate choice to this difficulty.ZigBee technology, as a recently emerging WPAN communications technology, has some characteristics such as simple agreement, low cost, low power consumption, easy to network, which makes it suitable for applying in low-cost, low-power wireless sensor networks. In this dissertation, based on the ZigBee technology and aimed at the needs of the real coal safety environment, the application of wireless sensor network in the mine monitoring systems is studied.According to the actuality of mine monitoring systems and the safety production needs of domestic small and medium-sized mine enterprises, the design proposal combining the parameter monitoring system with the personal locator and based on the ZigBee technology and wireless fiber network is put forward.The entire monitor network is composed of underground wireless network and optical fiber network which connected the wireless network and the monitoring computer. The wireless mesh network is composed of the fixed-nodes which based on wireless communication chips and single chip microcomputer and the portable nodes.All nodes upload the environmental parameters being sampled by the sensor to the monitor computers through the network. At the same time, the system locates the position of miner's by RSSI value between the nodes. The monitor computer shows the environmental parameters and the personnel location in real time. If some parameters exceed limits, the system will give warning information to the staff to deal with the problems.Finally, the system has been tested in a seal corridor and the results have been testified the feasibility of the system.