Coalmine Safety Monitoring Using Zigbee Wireless Sensors

International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 4, Issue 2, March – April (2013), © IAEME
504
COALMINE SAFETY SYSTEM WITH ZIGBEE SPECIFICATION
Miss. Smita B. Garde1
, Prof. S.L.Kotgire2
1
(Dept. of Electronics & Telecommunication, M.G.M.’s college of Engg. /S.R.T.M.
University, Hingoli road, Nanded, India)
2
(Dept. of Electronics & Telecommunication, M.G.M.’s college of Engg. /S.R.T.M.
University, Hingoli road, Nanded, India)
ABSTRACT
This paper provides a better solution for safety system of coalmines using Zigbee
wireless sensor networking. The proposed monitoring system collects temperature, humidity
and methane values at underground section of coalmine through zigbee sensor nodes and then
transmits the data to the receiver section which is present at the ground section of a coalmine.
When the received values cross the threshold level then buzzer will start alarming, at the
same time data will be displayed on the LCD screen which is present at both ground and
underground section. So that everyone present in/outside the coalmine should be alert about
the accident to be happened and it should be possible to provide an immediate help if
necessary. With this system it is possible to safe the manpower as well as coal as a natural
fuel.
Keywords: coalmine safety, LCD, monitoring system, wireless sensor node, Zigbee
specification.
1. INTRODUCTION
Up till now lot of systems are proposed for safety purpose of coalmines but it is
observe that most of them depends on the cable or wired network, very few of them use
wireless network but they are also not able to give the correct information about the number
of persons present inside the coalmine at the time of accidents. Because we observe that most
of them use the parameters like temperature, pressure, humidity, gas but not use such a
parameter which is use to detect exact number of persons present inside the coalmine when
an accident happened [1]. This system is design by considering all these parameters i.e. it can
INTERNATIONAL JOURNAL OF ELECTRONICS AND
COMMUNICATION ENGINEERING & TECHNOLOGY (IJECET)
ISSN 0976 – 6464(Print)
ISSN 0976 – 6472(Online)
Volume 4, Issue 2, March – April, 2013, pp. 504-512
© IAEME: www.iaeme.com/ijecet.asp
Journal Impact Factor (2013): 5.8896 (Calculated by GISI)
www.jifactor.com
IJECET
© I A E M E

505
sense temperature, pressure, humidity, gas as well as number of persons can also be measured by
using IR sensor nodes. When an accident happened, especially explosion, the sensors and cables
usually were damaged, and couldn't provide information for rescue search and detection events so
it is a better solution to design the safety system with wireless network [2].
This paper provides survey of previous work, design overview of the system, working of
components used in system designing.
2. LITERATURE SURVEY
As we know safety is one of the main aspects of industry specially mining industry as
coal is the ultimate natural fuel of the world. To avoid any types of unwanted phenomena, all
mining industries must follow some basic precautions. Communication is the main key factor for
any industry today to monitor different parameters and take necessary actions accordingly to
avoid any types of hazards. To avoid loss of material and damaging of human health, protection
system as well as faithful communication system is necessary inside the underground mines. To
increase both safety and productivity inside the mines, a reliable communication must be
established between workers, moving stations, and fixed base stations in the mine. The wired
communication system is not so effective inside mines. The reliability and long life of
conventional communications systems in harsh mining environments has always been a problem.
Due to uncomfortable situation in mines the cost of installation as well as maintenance is very
high for wired communication networks. It is very difficult to re-install the wired communication
system inside mines after a landslide or damage due to any reason. Due to roof fall, if by any
means some workers trapped inside mines, to maintain the continuity of the communication
system is very much important to know the actual position and condition of the trapped workers.
To monitor other parameters during this condition it is very much necessary to maintain the
communication system as usual. Accordingly, development of mine monitoring system to
accurately detect temperature, pressure, flammable and poisonous gas and to track underground
miners and vehicles on real-time has significant meaning to safety production and rescue of coal
mine disaster [2].
Coal mine safety monitoring system based on wireless sensor network can timely and
accurately reflect dynamic situation of staff in the underground regions to ground computer
system. There are different other research ideas proposed by different people on wireless
communication. For the successfully wireless data transmission, in this work the Zigbee
specification is used to design a monitoring system.
3. DESIGN OVERVIEW
Coalmines are specially divided into two main parts. The first section is underground
section and another section is ground section. Underground section is the main part of a coalmine
i.e. the area where actual work is done, so this section is design to sense different parameters like
temperature, pressure, humidity, and poisonous gases as these parameters affects the coalmine
environment adversely. The ground section is generally present outside the coalmine where the
control room is present which provide accurate information and help time to time when
necessary. The ground and underground sections are connected by means of a wireless link. Here
a zigbee specification is used as wireless link between two sections. The overall block diagram of
the system is as shown in Fig.1. The designed systems are placed in different parts of the mine.
Sensors present at underground section will sense the environment conditions such as
temperature, humidity, gas etc.., and this information is send to ADC of the micro controller,
Microcontroller displays this information in the LCD board and sends through Zigbee transmitter.
Ground section is having Zigbee receiver which collects this information and sends to the

506
controller and controller sends the information to GSM modem and at the same time the
information is displaying on the LCD present at ground section. Here GSM modem is used to
send the messages to everyone present inside the mine through mobile when sensors exits there
threshold level.
3.1 Under-ground section
Underground section of a coalmine consists of different sensor nodes, microcontroller,
Zigbee transmitter, LCD as shown in figure1. The sensor nodes sense the physical parameters
like temperature, humidity, pressure which are always in analog form. These analog quantities are
then sending to the microcontroller but microcontroller cannot take the data in analog form so it
needs to be converted first into digital form. That’s why we must select such microcontroller
which has inbuilt feature of analog to digital convertor. Here we select AVR controller.
Microcontroller checks these values and sends it to the ground section through Zigbee
transmitter. At the same time the values will be displayed on the LCD board, if any of the
received value crossed the threshold level then buzzer will be ON giving warning to the miners.
The number of people present inside the mine can also be detecting by means of IR sensor. This
information plays very vital role during a hazard to know whether there are any people remained
inside the coalmine. Information regarding the safety measure like wearing oxygen helmets etc.,
will be already given to the workers so that they can save their life.
Figure 1 General Block diagram of designed system

507
3.2 Ground section
The ground section consists of Zigbee module, microcontroller, LCD, PC and GSM
modem. PC and GSM are optional. In the Ground Section, the Zigbee receiver collects the
information and sends to the AVR controller. The LCD connected to the controller displays
the information in the Ground Section. The officers present inside the control room take
proper actions according to the displayed data on LCD and provide immediate help if
necessary. In additional to this controller is also connected to PC; to store the values for
future help. GSM modem is used to send the data to miners on mobile phones.
4. HARDWARE DESCRIPTION
4.1 AVR Microcontroller
In short we can say that it is High-performance, Low-power 8-bit Microcontroller. It
has Advanced RISC Architecture, 131 Powerful Instructions – Most Single-clock Cycle
Execution, 32 x 8 General Purpose Working Registers. And some extra features like it has
inbuilt Flash, SRAM and EEPROM memories. It is Available in 40-Pin DIP form with inbuilt
8-Channel 10-bit ADC, Timers/Counter, separate PWM Channels, and peripherals like In
System Programmer (ISP), Serial USART, SPI Interface, Digital to Analog Comparator etc.
Fig.2 shows physical port of microcontroller AVR of ATmega series.
Figure 2 Physical port of AVR
The parameters which we want to measure are physical parameters (i.e. in non–
electrical form). So as to convert it into electrical form we are using sensors. The output of
sensor is in analog in nature but microcontroller is not able to read this analog form of
parameters so to convert it into digital form we must require an ADC which is inbuilt in AVR
controller. ADC of controller converts these quantities into digital form and analyzed it for
taking proper action. After that controller ask ZIGBEE module it is ready to receive the data
or not. If zigbee is ready, then controller sends these data through UART to Zigbee
transceiver .The information is send to another zigbee module present at ground section. It
will receive it and decodes it. Then give it to AVR controller and according to information is
received, will display on LCD. Likewise information will be updated after every fixed
duration [1].

508
4.2 Zigbee module
This section presents a Zigbee wireless specification used to build a safety system for
coalmines. This paper prefers this specification by considering all the features like frequency
bands, transmission speed etc. Instead of zigbee we may use other wireless communication
link as RFID, Bluetooth, Wi-Fi, Wi-max. But zigbee is somewhat better than other links
which will be cleared from following comparison table. Table 1 shows difference between
some wireless specifications.
Table 1 Comparison between wireless specifications
Features IEEE 802.11b Bluetooth Zigbee
Battery Life Hours Days Years
Complexity Very complex Complex Simple
Nodes/master 32 7 64000
Latency Enumeration up to 3
seconds
Enumeration up to 10
seconds
Enumeration up to
30ms (to 1 second)
Range 100 Meters 10 Meters 70-300 Meters
Extendibility Roaming Possible No Yes
Data rate 11 Mbps 1 Mbps 250 Kbps
Security Authentication
service set ID (SSID)
64 bit, 128 bit 128 bit AES and
Application layer
As we know the basic components required for any wireless communication links are
transmitter, receiver, antenna and transmission medium.
Figure 3 Basic components of wireless communication link.
For zigbee specification one common zigbee module can be used as a transmitter as well as
receiver and called as Zigbee transceiver. It has on-chip antenna as shown in fig.4 given
below.

509
Figure 4 Zigbee transceiver
In few words I would like to say: zigbee is a “low cost, low power, very diverse
possibility”. Zigbee is a wireless networking standard that is aimed at remote control and
sensor applications which is suitable for operation in harsh radio environments and in isolated
locations. It is IEEE standard 802.15.4 which defines the physical and MAC layers; also
Zigbee defines the application and security layer specifications enabling interoperability
between products from different manufacturers. Hence we can say Zigbee is a superset of the
802.15.4 specification. The 802.15.4 standard is primarily aiming at monitoring and control
applications. Low power consumption is the most important feature that makes battery
operated devices operates for a long time. The amount of data throughput (bandwidth) is
relatively low compared to wireless LAN for example, but with 250kbps for many
applications more than enough. The distance between 2 nodes can be up to 50 meters but be
aware the each node can relay data to the next making a very big network, covering
significant distances, possible. It is more beneficial due to its features like it has an in-built
antenna, 400 ft (120 meters) range, 250kbps maximum data rate. 8 to 10 digital input-output
pins etc. [4].
4.3 MAX232
Microcontroller operates at TTL logic level (0-5 V) level whereas the serial
communication in PC operates on RS232 standard (Recommended Standard). RS232 is a
standard for serial binary data signals connecting between a DTE (Data Terminal Equipment)
and a DCE (Data circuit –terminating Equipment).
Usually all the digital ICs work on TTL or CMOS voltage levels which cannot use to
communicate over RS232 level. So, a voltage or level convertor is needed which can convert
TTL to RS232.The most commonly used RS-232 level converter is MAX232. As mentioned
earlier, RS232’s voltage levels are not compatible with microcontroller so to make it
compatible MAX232 is used, which is known as line drivers. It converts the TTL levels to
RS232 voltage levels and vice versa. Pin no 13 and 14 of MAX232 (i.e. R1in and T1out
respectively) are connected to pin no. 2 and 3 of RS232 and pin no 11 and 12(i.e. T1in and
R1out respectively) of MAX232 is connected to pin no 11 and 12 of microcontroller. It
requires four capacitors ranging from 1 to 22uF. Most widely used is 22uF. Fig.5 shows
interfacing and pin diagram of MAX232level convertor IC.

510
Figure 5 Interfacing and Pin diagram of MAX232
Advantage of MAX232 is that it uses 5V power supply which is same as for microcontroller.
4.4 LCD
An electronic display module which is widely used in portable DVD players, TV’s,
video scan convertor box, computers, cell phones etc. It is a type of screen which can display
the data in alphanumeric form i.e. it can display letters as well as numbers. It has wide range
of applications and available in various modules. A 16x2 LCD module is one of the common
display module and used in various devices and circuits. These modules are preferred over
seven segments and multi segment LEDs due to its features like more economic, easily
available and easily programmable. Also it has no limitation of displaying special characters
or custom characters unlike seven segments. Though LCD’s are very thin but actually it has
several layers. Those layers include two polarized panels, with a liquid crystal solution
between them. Light is projected through the layers of crystals and is colorized, which
produces the visible image. LCDs are also able to display animations. A 16x2 LCD means it
can display 16 characters per line and there are two such lines. Here each character has some
fix value or space, which is measured in pixel like image. For each character 5x7 pixel matrix
is decided by default. This LCD has two registers, namely, Command and Data. The
command register stores the command instructions given to the LCD to do a predefined task
like initializing it, clearing screen, controlling display etc. Data registers are used to store the
data to be displayed on LCD. The data is nothing but the ASCII value of the character to be
displayed on LCD.

511
5. SYSTEM FLOWCHARTS
Fig.6 gives the flowcharts for underground and ground sections.
Figure 6 Flowcharts of designed system
6. CONCLUSIONS
This paper gives a better solution for a safety system for coalmines with a new
wireless specification i.e. Zigbee. Here we are displaying the parameters on LCD at both
ground and underground section; it will be helpful to all miners present inside the mine to
save their life before an accident. For future help we are storing the parameters in PC.
Messages can also be send to all miners when sensor values crossed the threshold level.
Zigbee is lifelong device; so it avoids the replacement of system frequently.

512
REFERENCES
1. S.Vandana, V.B.Sundheep, Development of Coalmine Safety System using Wireless
Sensor Network, International Journal on Computer Science and Engineering (IJCSE)
Vol. 3 No. 5 May 2011, ISSN : 0975-3397.
2. MO LI and YUNHAO LIU, Hong Kong University of Science and Technology,
Underground Coal Mine Monitoring With Wireless Sensor Networks, ACM
Transactions On Sensor Networks, Vol. 5, No. 2, Article 10, Publication Date: March
2009.
3. Tanmoy Maity, Partha Sarathi Das, Mithu Mukherjee, A Wireless Surveillance and
Safety System for Mine Workers based on Zigbee, 1st International Conf. on Recent
Advances in Information Technology, RAIT-2012.
4. Swathi Bhupatiraju, T J V Subrahmanyeswara Rao, Design and Automation of Security
Management System for Industries Based On M2M Technology, International Journal of
Computer Engineering Science (IJCES) Volume 2 Issue 3 (March 2012) ISSN :
2250:3439.
5. Sarang D. Patil. and Prof. S.N. Pawar, “Wireless Amr System Using Zigbee
Technology”, International Journal of Electronics and Communication Engineering
&Technology (IJECET), Volume 3, Issue 2, 2012, pp. 107 - 115, ISSN Print: 0976-
6464, ISSN Online: 0976 –6472.
6. Ansari Md.Asifmd Riyasat, Vijayshree A More, Prof.J.G.Rana and Dr.S.A.Naveed,
“Green House Monitoring Based on Zigbee”, International Journal of Computer
Engineering & Technology (IJCET), Volume 3, Issue 3, 2012, pp. 147 - 154, ISSN Print:
0976 – 6367, ISSN Online: 0976 – 6375
AUTHOR’S PROFILE
1
Miss S.B.Garde, a PG Scholar in M.G.M.’s college of Engg. Nanded (MH). The post
graduation specialization is Electronics and telecommunication. She graduated from
Anuradha college of Engineering, chikhali, Amravati University in the stream of Electronics
and telecommunication Engineering. She is working as a lecturer at Pankaj laddhad Institute
of technology & management studies, Buldana, Amravati University from last 2 years.
2
Prof. S.L.Kotgire, PhD(Scholar), Principal at M.G.M.’s College of CS & IT, Nanded,
Assistant professor, Department of Electronics and Telecommunications Engineering,
M.G.M.’s college of Engineering, Nanded (MH). He has completed graduation & post
graduation in the stream of Electronics and telecommunication Engineering and Teaching
Experience of 24 years.

Coalmine Safety Monitoring Using Zigbee Wireless Sensors

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (20)

Ähnlich wie Coalmine Safety Monitoring Using Zigbee Wireless Sensors

Ähnlich wie Coalmine Safety Monitoring Using Zigbee Wireless Sensors (20)

Mehr von IAEME Publication

Mehr von IAEME Publication (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Coalmine Safety Monitoring Using Zigbee Wireless Sensors