A Coal Mine Environmental Monitor System with Localization Function Bad on ZigBee-Compliant Platform
Dongxuan Yang
College of Computer and Information
Engineering
Beijing Technology and Business
University
Beijing, China
Yan Chen
College of Computer and Information
Engineering
Beijing Technology and Business
University
Beijing, China
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Kedong Wang
College of Computer and Information
二元一次方程解法Engineering
Beijing Technology and Business
University
Beijing, China
怎么卤鸡爪
Abstract—This paper describes and implements a new type of汉口花园 coal mine safety monitoring system, it is a kind of wireless nsor network system bad on ZigBee technology. The system consists of two parts underground and surface. Wireless nsor networks小豆长喙天蛾 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 also calculate the real-time location of mobile nodes worn by miners.
Keywords： ZigBee; localization; wireless nsor networks; coal Mine
.RESEARCH STATUS
As an important energy, coal plays a pivotal role in the economic development. Coal mine monitoring system, is the important guarantee for coal mine 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 ud traditional monitoring node wired connection to obtain communication with the contr
ol system, this node exist wiring difficulties, expensive and other shortcomings. In contrast, wireless nsor 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 wireless 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 u.
The ZigBee wireless communication technology is ud in this coal mine environmental monitor system. This is a new short-range, low complexity, low power, low data rate, low-cost two-way wireless communication technology [2]. Now, wireless nsor network product bad on ZigBee technology are quantity and variety, but the real product can be applied in underground environments of special nsor node is very few[3]. The nsor node that we designed in the system is truly able to apply to in-well environment, it through the wireless nsor node curity 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 provides more protection [4].
花为谁开. SYSTEM ARCHITECTURE
This system is a comprehensive monitoring system which 武夷山大红袍多少钱一斤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 environment data and require person’s location. Software part refers to the PC monitoring software which is designed in VC++ is ud 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 data. Becau the fixed node is also using wireless data transmission method, so it's deployed in the underground roadway becomes very convenient. As the mobile node is carried by the miner, it must be using wireless 红糖的功效transmission method. This allows the mine to form a topology of ZigBee wireless nsor network. The fixed node in wireless nsor network is router device and the mobile node carried by miner is the end device. Normally, the router of ZigBee network has no nsor equipment; it is only responsible for data forwarding. But considering the practical application, we believe that add 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 nt received data from mobile node to the gateway, then the gateway transmits data 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 node’s real-time location through the specific localization algorithm, according to the received signal strength (RSSI) obtained from mobile nodes.
. NODE DESIGN
Since the ZigBee wireless network platform sold on prent 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 environment whit a special hardware circuit. Node photo are shown in Fig. 1
Then 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, supporting 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 u a single MCU to control the circuit, and this save us a lot of cost [5].
A.Mobile Node
The 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 processor CC2530 is a low power consumption chip, when it is in the sleep mode, it only need to u 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 ud. The battery’s capacity of the mobile node is 1500mA
h, so it is enough to meet the miner’s 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 nsor MJ4.0 and temperature nsor PT-1000. As far as we know, many wireless nsor platforms u the digital type nsor. The communication between the digital nsor 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 u the microcomputer to 盯防simulate the strict timing, it will affect the real-time of whole operating system. The two nsors 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 CC2530 chip. In order to facilitate the carrying, external antenna was not ud 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, nsors and battery in it. Taking into account the small shell of the explosive performance is not very good, the design of PCBs and the lection of component are all carried out the safety asssment.
