To describe a potential application for environmental monitoring in ... Wireless sensor network is composed of a set of small sensor nodes deployed in an ad.
Design of Wireless Sensor Network for Mine Safety Monitoring
Abdellah Chehri♦, Wissam Farjow♣, Hussein. T. Mouftah♦, Xavier Fernando♣ ♦ School of Information Technology and Engineering, 800 King Edward Avenue Ottawa, Ontario, Canada, K1N 6N5 ♣ Dept. of Electrical and Computer Eng. Ryerson University, 350 Victoria Street Toronto, M5B 2K3 1
I. Introduction II. ZigBee based Sensor Networks.
Outline
III. System Description IV. Results and discussions V. Conclusion.
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Introduction Motivation
Motivation Over past decade, there has been a surge of accidents in mines across the words. The emergence of WSN in the industrial applications. The importance of sensor networks in mining industry application lies in its simplicity coupled with a good efficiency. In a disaster, (i.e., fires) the conventional wired sensor networks may become unreliable, necessitating a wireless radio system.
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Introduction Motivation • Our Goal To describe a potential application for environmental monitoring in underground environments. Real time monitoring of gases and other parameters. Monitoring equipment locations and operation statuses to improve productivity and reduce fatal collision accident; Locating and tracking miners in case of disaster for emergency rescue operations. Tracking and monitoring assets equipment Monitoring miner’s unsafe practices and warning;
During the normal operation, the networks can be used to track the miners and for security monitoring.
We evaluate the performance of WSN for mine safety monitoring.
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Introduction Wireless Sensor Networks
Fig. 1: simplified sensors networks Wireless sensor network is composed of a set of small sensor nodes deployed in an ad hoc fashion that cooperate for sensing a physical phenomenon. Sensor networks are among the most significant technologies of 21 century. The concept of sensor networks: Sensor , CPU , radio = several potential applications.
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Introduction Characteristics of wireless sensor networks
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The assets of WSN in mining industry
Economic: wiring costs 80% of the price of installation
An obvious advantage of wireless transmission is a significant reduction and simplification in wiring and harness. (the wiring cost in industrial installations is US$ 130 - 650 per meter, and adopting wireless technology would eliminate 20-80 % of this cost.
Safety: take measurements where the wiring is impossible (or difficult) Wireless sensors allow otherwise impossible sensor applications, such as monitoring dangerous, hazardous, unwired or remote areas and locations. Simple: Wireless sensor networks allow faster deployment and installation Self-organizing, Self-configuring, Self-diagnosing and self-healing capabilities, flexible extension of the network,...
Introduction The assets of WSN in mining industry Applications Environmental data measurement Temperature; Humidity; Luminosity…. Security Monitoring Fire detection; Toxic gas detection (Carbon monoxide , Methane…); Oxygen concentration …. Radiolocalisation Localization of the works and machine,… Rescue services Traffic management in the mine.
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ZigBee based Sensor Networks
The ZigBee is a commercial standard which has been developed from IEEE 802.15.4. Low data rate. Short rage operation. Very Low power consumption . Low cost wireless networking devices. Ease of implementation. Applications Home Networking Automotive Networks E-health Applications. Industrial Networks Remote Metering.
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ZigBee based Sensor Networks
The IEEE 802.15.4 employs a long 64 -bit address and a short 16 -bit address. Theoretically, the short address supports over 65 535 nodes.
Support for low latency devices. Data rates of 250 kb/s, 40 kb/s and 20 kb/s. Fully handshaked protocol for transfer reliability. Low power consumption. Frequency Bands of Operation 16 channels in the 2.4GHz ISM band
10 channels in the 915MHz ISM band 1 channel in the European 868MHz band.
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ZigBee based Sensor Networks ZigBee Protocol Stack
Figure 2: Full ZigBee Protocol Stack
Fig. 3 General Mac Packet Format
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System Description When choosing deployment of WSN in underground mine, for mine safety monitoring, it should be necessary to make a compromise between technical limitations and requirements. Many technical limitations: Processing power, Synchronization, Network robustness, Energy and memory constraints Requirements ( guarantee network function with maximum efficiency and reliability. ) Flexible, Multi-hop networking, Several architectural topologies. To improve the flexibility and reliability of the network, the multi-route topology, where each node is relayed to sink is the suitable choice. So, if a single node, the remitted data can automatically routed through alternate paths.
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System Description
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the sensor nodes deployed in the appropriate areas: To collect the environmental data (temperature, oxygen concentration, humidity). To detect possible anomalies like a fires, explosions (gas explosions, dust explosions, premature explosions of charges), toxic gases (Carbon monoxide, Methane), or even a roof failure. These collected data are transmitted to the sink node using multi-hop routing.
After reception, the sink nodes combine its collected data and forward it to the gateway (Wireless Personal Area Networks). The observer can query for information from the network.
Based on this architecture, the underground mine remote monitoring becomes possible.
Fig. 4: Architecture for WSN in underground mines (the graph is projected on the 2D plane).
Results and discussions
We evaluate the performance of WSN for mine safety monitoring using ns-2.
We set a 100 m x 100 m area to simulate an underground mine gallery. We consider a complex static network configuration with 25 nodes. At the end of the gallery sits the ZigBee coordinator. It also acts as gateway server, collecting data from different sensors. Each sensor of the system was mounted at different locations.
Fig. 5: Deployment of WSN using ns2.
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Results and discussions
Results and Discussions
Throughput and Average Reception Ratio Analysis
We evaluate average reception ratio and throughput of the whole network. We position each WSN along one certain route to the gateway (short route). 4
(b)
(a) Average Reception Ratio
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0.9 0.8 0.7 0.6 0.5
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Hop (c)
0.3 Average Delay (s)
• Fig. 6. (a) depicts the throughput for between node and sink for direct link. • When sensors are directly connected to the sink, like a star network, almost all packets have reached the destination, exhibiting a throughput up to over 20 Kbps. • However, when one more hop is introduced into sink and sensor nodes, network throughput degrades (to 6 Kbps).
Throughput (bps)
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0.25 0.2 0.15 0.1 0.05
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Fig. 6: Simulation results (a) Throughput Analysis (b) Average Reception Ratio Analysis (c) Link Latency Analysis.
Results and discussions
Link Latency Analysis
We examine in this subsection how the ZigBee network performs in terms of average delay. Simulation results are shown in Fig. 6. (c). The delay increases as the number of hops increases on the ZigBee link. We note the results show a varying of average delay from 0.1 to 0.3 second. This is promising as such a delay is acceptable to most WSN monitoring and security application as well.
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Results and discussions
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Packet loss vs. number of hop The other two main parameters that can affect the PER is the transmitted power and number of hop. By transmitting at different level.
We evaluate their impact on PER. The evaluation was conducted for three transmission power levels 0 dBm, -10 dBm, and -15 dBm.
Fig. 7: Packet loss rate vs. number of hop for different transmission range.
Results and discussions
• Real applications of WSN are being explored and some of them are yet to come. • While the potential of sensor networks in underground mine is only beginning to be realized, several challenges still remain. Some Challenges • Power consumption always an issue. • The complex nature of wave propagation in underground mine. • Topology change due to human activity (system should scale well on a large number of topologies). • It is necessarily to take into account the characteristics of the mine, like gallery size and shape, and the desired coverage. • Radio connectivity varies over time and is very sensitive to position.
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Conclusion Conclusion
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• We have described the potentials applications of using wireless sensor networks in an underground mine. • We examined the reliability for both point-to-point communication and multihop communication using IEEE 802.15.4 standard. • These performances are measured in term of delay, throughput and packet error rate. • The first results show that it is possible to monitor mine from remote locations using the WSN without reasonable delay. • In the future, more scenarios will be investigated.
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Thank you
