Design Of Coal Mine Safety Monitoring System Based On Internet Of Things

In China’s energy industry, coal production accounted for76%of the total production of primary energy resources, and coal consumption accounted for69%of the total consumption of primary energy resources. For China are generally underground mining, so there are many hidden danger threatening the safety of the mine staff such as the harsh production environment, gas projection and coal dust pollution. According to statistics, in China’s key coal mines, high gas mine accounted for about44.4%and about91.35%of the mine has the hazard of coal dust explosion. Only in2012, there are350people be killed in72cases of gas accident. Therefore, the coal mine safety monitoring is particularly important.At present, our country coal mine monitoring system for gas detection is mostly used in thermal catalysis method. Its principle is using catalytic to release heat continuously in low temperature environment. This kind of equipment has a good effect in low concentrations. However the long-term use or when the concentration is high; it is not only easy to poisoning, shorten life, but also increase the measuring error, and so from time to time must be calibrated. In addition, for the coal mine monitoring system is cable system, all the instruments are connected to the bus. But the bus wiring has the shortcomings of complexity, high coast, limited coverage area, poor expanding ability and low flexibility. Speciously in the event of an accident, the cable will be damaged fatally, and can not be able to provide timely and effective information. This will be a serious threat to the safety of the staff. Aiming at these problems and the current market demand, this paper designs a coal mine safety monitoring system based on the internet of things. So this design can measure the mine safety information with high precision, make wireless transmission with high fidelity and can realize remote monitoring through internet whenever and wherever. In order to reduce the system coast, shorten the development cycle, and improve the system’s versatility, this system adopts modular design. Each part can be made into a separate module. So this system can not only used in coal mine, can also be used in other fields.The system consists of the sensor module, data acquisition module and network, Ethernet gateway module. In the sensor module, measure gas using absorption method. The theory is based on the Lambert-Bill’s law. The concrete implementation method is using absorption method of difference between the dual wavelength with single light source and path in hardware, and using piecewise least square method and temperature compensation algorithm in software to translate concentration. On data transmission, connect RS-232serial port with data acquisition terminal, The core controller uses low-power MSP430MCU to convenient for debugging and equipment. The module sets up analog interface、switch interface and output control and so on to realize the low cost, low power consumption, high stability and high accuracy, high sensitivity. Experimental results show that the absolute error is less than0.1%, the response time is less than5s, and the stable time is less than15s. Data acquisition terminal module and network using Zigbee Technology, Topology named cluster-tree network, Using CC2530as a platform, with the universal serial to ensure the universal property of equipment. And achieve docking with the other modules perfectly. Ethernet gateway module uses a serial-to-Ethernet technology. In order to reduce the cost and difficulty of development, LM3S9B96has been chosen as the hardware platform. The software based on drive library offered by the TI, greatly reduced the exploitation cycle, and realize the conversion of serial protocol and TCP/IP protocol. After access network the user can check this safety information of coal mine at any time by the remote computer.At present, there are few example of such systems used in coal mines. According to the provisions of the state and the demands of the market, in line with the principles of low cost, high precision and high stability, the author designs and develops mine safety monitoring system based on network. And the prototype has produced; laboratory testing is coming to an end. It will have a good market prospects.