煤矿安全监控系统外文翻译.docx

1、煤矿安全监控系统外文翻译A Coal Mine Environmental Monitor System with Localization Function Based on ZigBee-Compliant PlatformDongxuan YangCollege of Computer and InformationEngineeringBeijing Technology and BusinessUniversityBeijing, ChinaYan ChenCollege of Computer and InformationEngineeringBeijing Technology

2、 and BusinessUniversityBeijing, ChinaKedong WangCollege of Computer and InformationEngineeringBeijing Technology and BusinessUniversityBeijing, ChinaAbstractThis paper describes and implements a new type of coal mine safety monitoring system, it is a kind of wireless sensor network system based on Z

3、igBee technology. The system consists of two parts underground and surface. Wireless sensor networks are constituted by fixed nodes, mobile nodes and a gateway in underground. PC monitoring software is deployed in the surface. The system can not only gather real-time environmental data for mine, but

4、 also calculate the real-time location of mobile nodes worn by miners.Keywords： ZigBee; localization; wireless sensor networks; coal Mine.RESEARCH STATUSAs an important energy, coal plays a pivotal role in the economic development. Coal mine monitoring system, is the important guarantee for coal min

5、e safety and high efficiency production 1. In order to ensure the safe operation, the installation of environment monitoring node in tunnels to real-time detection is very important. However, commonly used traditional monitoring node wired connection to obtain communication with the control system,

6、this node exist wiring difficulties, expensive and other shortcomings. In contrast, wireless sensor node can be easily with current mine monitoring network connection, and good compatibility, facilitate constituted mine gas monitoring network, to suit various size of mine applications. Since wireles

7、s nodes are battery powered, so completely out of the shackles of the cable, shorten the construction period can be arranged at any time where the need to use.The ZigBee wireless communication technology is used in this coal mine environmental monitor system. This is a new short-range, low complexit

8、y, low power, low data rate, low-cost two-way wireless communication technology 2. Now, wireless sensor network product based on ZigBee technology are quantity and variety, but the real product can be applied in underground environments of special sensor node is very few3. The sensor node that we de

9、signed in the system is truly able to apply to in-well environment, it through the wireless sensor node security certification. At the same time, due to the special nature of the wireless network is that it can spread the wireless signal, we can easily locate staff for coal mine safety monitoring pr

10、ovides more protection 4. SYSTEM ARCHITECTURE This system is a comprehensive monitoring system which is combined with software and hardware. Hardware part includes wireless mobile nodes and fixed nodes which were deployed in the underground tunnel, the main function of them is to collect coal mine e

11、nvironment data and require persons location. Software part refers to the PC monitoring software which is designed in VC+ is used to summarize and display the data of each node. Monitoring node is divided into mobile nodes and fixed nodes; they are using ZigBee protocol for wireless transmission of

12、data. Because the fixed node is also using wireless data transmission method, so its deployed in the underground roadway becomes very convenient. As the mobile node is carried by the miner, it must be using wireless transmission method. This allows the mine to form a topology of ZigBee wireless sens

13、or network. The fixed node in wireless sensor network is router device and the mobile node carried by miner is the end device. Normally, the router of ZigBee network has no sensor equipment; it is only responsible for data forwarding. But considering the practical application, we believe that add se

14、nsor devices on the router will be better on monitoring underground coal mine environment. So in our design, the router also has an environment monitoring function which is usually designed in end device.Fixed node will sent received data from mobile node to the gateway, then the gateway transmits d

15、ata to monitor computer through RS232 or optical fiber. The PC monitor software in the computer will process all data and display them in a visualization window. The PC software also calculates each mobile nodes real-time location through the specific localization algorithm, according to the receive

16、d signal strength (RSSI) obtained from mobile nodes. NODE DESIGNSince the ZigBee wireless network platform sold on present market was designed for the general environment, for special underground so they are not suitable for the environment. Therefore, we need to customize the system for underground

17、 environment whit a special hardware circuit. Node photo are shown in Fig. 1Then wireless microcontroller CC2530 chip is the core processor of the node device, it can constitute a ZigBee network with very few peripheral circuits. The CC2530 is an IEEE 802.15.4 compliant true System-on-Chip, supporti

18、ng the proprietary 802.15.4 market as well as the ZigBee, ZigBee PRO, and ZigBee RF4CE standards. Unlike other wireless chip, CC2530 built-in 8051 monolithic integrated circuits kernel, therefore we no longer need to use a single MCU to control the circuit, and this save us a lot of cost 5.A. Mobile

19、 NodeThe mobile node is the end device of a ZigBee network that can be carried by miner; it should be a portable and low power consumption node. So the mobile node we designed is only as small as a mobile phone, and it is by built-in lithium ion battery power supply. In power loss, the core processo

20、r CC2530 is a low power consumption chip, when it is in the sleep mode, it only need to use less then 1uA work current. In order to reduce power consumption as much as possible on the display, a 100*32 pixel matrix with no backlighting LCD screen was used. The batterys capacity of the mobile node is

21、 1500mAh, so it is enough to meet the miners long hour works in the underground. The battery charge management chip is TP4057, the maximum charge current can up to 500Ma.Figure 1. Node photo.The mobile node circuit includes the gas concentration sensor MJ4.0 and temperature sensor PT-1000. As far as

22、 we know, many wireless sensor platforms use the digital type sensor. The communication between the digital sensor and the MCU need strict timing requirements. But considering the actual application, the wireless MCU usually has a real-time operating system in general, if we use the microcomputer to

23、 simulate the strict timing, it will affect the real-time of whole operating system. These two sensors output analog signals not digital signals. Only input this signal into a differential amplifier, can we get an appropriate signal that can be converted to a digital signal by an ADC mode within the

24、 CC2530 chip. In order to facilitate the carrying, external antenna was not used in our mobile node, instead of using a 2.4GHz patch antenna. And we customize a shell like a cell phone size; it is enough to put all PCBs, sensors and battery in it. Taking into account the small shell of the explosive

25、 performance is not very good, the design of PCBs and the selection of component are all carried out the safety assessment.B. Fixed NodeFixed node is installed in the wall of the underground tunnel. Because it is big than the mobile node, it is not appropriate to carry around. The circuit of the fix

26、ed node is almost same with the mobile node, it also use a CC2530 chip as core processor. Because of underground tunnels generally deploy with power cable, fixed nodes can use cable power-supply modes. At the same time, because we use wireless signal transmission, the deployment of new fixed nodes b

27、ecome very convenient, which also resolves the problem of the signal lines deployment.As a fixed node, the minor who is doing work may far from it, in order to facilitate the miners observed environmental data around the fixed nodes, it uses LED digital display. At the same time, the large current L

28、ED lights and buzzer are designed in the circuit; it makes the fixed node with the function of sound-light alarm. Considering that it may occur the emergency of without electricity, fixed node also built-in a lithium-ion battery. Under normal conditions, lithium-ion battery is in charging status, wh

29、en external cable disconnect, fixed node is automatic switched to battery power, which can ensure the mobile node can deliver the information through fixed nodes in underground.Without regarding to fixed nodes portability, we have a customized shell that has excellent explosion properties, and the i

30、nternal space is enough to hold down the 2.4 GHz antenna. To ensure safety, all cables and the location of sensors are placed with particular glue sealed, so that it has a good seal. POSITIONING FUNCTION One of the important functions of the wireless sensor networks is localization, especially in th

31、e underground tunnel, it relates to the safe of the miners life. Currently most widely used orientation method is GPS satellite positioning, it is a high precision, all-weather and global multifunctional system with the function of radio navigation, positioning and timing. But the GPS positioning me

32、thod is not suitable for the underground work environment of coal mine, once you enter the underground, it cannot receive satellite signal, thus unable to achieve targeting 6. We need to consider how to use wireless network to realize positioning function, means using wireless signal between the communications of devices for positioning. The existing distance measuring technology between the wireless-devices basically is the following kinds of methods: TOA, TDOA, AOA and RSSI. About the TOA method, the distance between the two devices is determined by the product of the speed o