International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
A Surveillance Robot for Disaster Sites
Mr. Sreejith K G#1 , Mr. L Raja#2
#1
KSR College of Engineering, Tiruchengode, PG Student(Embedded System
Technologies),Sreejith.george@gmail.com
#2
KSR College of Engineering, Tiruchengode, Assistant Professor (ECE Deptartment),
rajabvni@gmail.com
ABSTRACT
In this project the design of a wireless controlled surveillance robot with an efficient semi
automatic navigation system is proposed for rescue applications. It can help men at disaster
sites and dangerous areas where sending human beings is very risky. The mobile robot in the
shape of small car equipped with various sensor for detecting causalities and analyzing the
environment such as human body detector, fire detector, sound detector, camera etc. The
navigation systems consist of Global Positioning System (GPS) and Ultrasonic sensors. All
the working of the robot is controlled and coordinated by an ARM7TDMI-S core based
microcontroller, LPC2138. The controlling units consist of Wireless-Fidelity (Wi-Fi) module
in the robot and a Wireless-Fidelity (Wi-Fi) enabled laptop with application software. This
system is optimized for rescue application in the sense of functionality, accuracy, efficiency
and cost effectiveness. This system can be modified by changing the sensors according to the
situation in which we indented to use it.
Key words: - surveillance, semiautomatic, automatic, gas detection, human detection.
Corresponding Author: Mr. Sreejith K G
INTRODUCTION
Robots are meant to aid people, making a task easier or aiding a person who wants or needs
help. The main use of robots has so far been in the automation of mass production industries,
where the same, definable tasks must be performed repeatedly in exactly the same fashion.
Also, domestic robots are now available that perform simple tasks such as vacuum cleaning
and grass cutting.
Recently, there has been interest in sending robots into situations that are too
dangerous to send a person. Some examples of these situations are buildings on fire and
buildings that are partially collapsed after an earthquake. In these situations, it is safer to send
a robot into the building to investigate it, before the rescue team enters. Some other robots are
used in other dangerous situations such as bomb disposal, mining, or cleaning of toxic waste.
In order to control the robot, a tether may be used. The problem with using a tether is that it
can become snagged; the tether may also be heavy or inflexible. For these reasons, robots
could use wireless communication as an alternative. A problem with wireless communication
is that it is not always reliable when attempting to control a robot from outside a building. For
these reasons, robots in these situations need to operate autonomously. Autonomy is the
degree of ability the robot has to make decisions without external control input but instead
use information gathered from onboard sensors.
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International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
2. SYSTEM ARCHITECTURE
The system architecture can be divided into two sections as hardware architecture and
software architecture. The following sections give a brief idea about the both of the
architectures.
2.1 Hardware Architecture
The hardware section contains a microcontroller which act like the brain of the system. In this
system it use LPC 2138 an ARM7 TDMI-S based advanced and cost effective
microcontroller well suited for applications which need to process images and many other
signals with very high reliability and efficiency. The sensors used for detecting objects and
analyzing situations are interfaced with the controller. The overall block diagram of the
system is given by figure1.
Figure 1.overall block diagram
The surveillance robot (Robot Car) is controlled and monitored by using a laptop. The robot
is connected to the laptop using Wi-Fi. The user front section with laptop contains small and
simple application software developed by using .visual basic (VB). The detailed block
diagram of Robot section is given in figure2
Figure2. robot section
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International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
2.1.1 LPC2138 microcontroller
It is high performance, low power, small size ARM7 based microcontroller. It can provide
execution speed in nano seconds which guarantee fast response times for critical interrupts. It
provides a lot of inbuilt peripherals which make the design easy and compact. It is a 32 bit
microcontroller providing 47 multipurpose pins grouped into two groups, port0 and port1. It
also has inbuilt ADCs, UARTs, Timers etc. It provide non maskable external interrupts and
fast interrupt request (FIQ) facilities. It also provide memory interfacing capacity up to 4GB.
Since is a RISC machine, coding for LPC2138 is relatively easy and can be carried out using
Keil software.
2.1.2 Sensors
This system used many sensors which is very essential for surveillance applications in
disaster sites and dangerous areas. They provide the human like cognition [1] for the system.
The sensors used in this system are
a) PIR - For human body detection. It is connected to one of the ADC channel.
b) GPS - Locating the position. It connects to the microcontroller through a switch and
UART. The switch multiplex the signals from GPS and camera
c) Temperature and light- For detecting fire. These sensors are connected through ADC
channels
d) MIC - Sound detection. It is also connected to the microcontroller through ADC channel.
e) Gas sensor - For detecting the presence of poisons gas and it is connected through the
ADC channel.
f) Camera - For taking pictures. Camera is connected to the switch to which GPS is
connected and the switch is connected to microcontroller via UART
g) Ultra Sonic Sensor – It is for detecting obstacle in the path. This module is connected to
the external interrupt pin of the controller
2.1.3 Wi-Fi
All the communication to and from the robot is carried out by means of wireless
communication by using Wi-Fi. A Wi-Fi module is interfaced to the microcontroller through
UART. In user front section the Wi-Fi facility of laptop is utilized. Wi-Fi connectivity
provide communication within 1km radius.
2.1.4 Working
The brain or core of the Robot section is a ARM based microcontroller named as LPC2138.
All other sensors and actuators are controlled and organized by the microcontroller. The
working of the system can be viewed as two sections, navigation and detection.
2.1.4.1 Navigation
Navigation of the robot deals how to control the motion of the robot while searching some
areas. The navigation system consist of DC motor for driving the wheels, Servomotor for
rotating the wheels and also for rotating the camera, US sensors for detecting the obstacles
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International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
and a GPS module to locate the robot. The robot can work in two modes ie, semi automatic
mode and fully automatic mode
Semi automatic mode: This is the default mode. In this mode we send the vehicle by starting
the DC motor. The vehicle moves forward until it detects some obstacle in front of it by using
the US sensors. When it detects an obstacle it gives an alert to the user. On the reception of
alert we switch on the camera and take snaps in all the 180 direction to identify the obstacle
and direct the robot. This mode can provide deterministic reach time by avoiding the
unnecessary trapping of the robot in some small bounded areas as in the case of fully
automatic modes. And also it can save bandwidth by avoiding the continuous real time video
capturing as done in manual controlling robots. This mode avoids the useless running of
robot to find path which in turn reduce the time to reach and increase battery life.
Fully automatic mode: In some situations like very poor light conditions or if the user is busy
with some other work the robot switched into automatic navigation mode. The switching is
based on the delay to give commands on reception of the obstacle alert. If robot doesn’t get
any response from the user for a particular time delay after giving the obstacle alert it
automatically starts the automatic navigation mode and find a way to avoid the obstacle. The
wheels of the robot are connecting by using a belt as in the war tanks which help it to move
even in very uneven surfaces. The ARM based controller ensures fast and accurate alert and
responses.
2.1.4.2 Detection
The robot is equipped with a lot of sensors other than the ones used for navigation. These
sensors make it suitable for rescue applications in disaster sites. The sensors include PIR for
human body detection for finding victims trapped inside the collapsed buildings. For
analyzing the situation fire and poisonous gas detectors are provided. There is a sound
detector also present it is to detect sound for checking anyone ask for help etc. Once we
detect the victim or some critical situation we can locate the area by using the GPS module
and images can also be capture by using the camera. After that we can take the necessary
actions for rescue mission. All the sensor outputs are interfaced to the controller and from
controller this information is send to the controlling section or to the operator by means of
Wi-Fi. Wi-Fi connection is enabled by incorporating a Wi-Fi module which is a standalone
controller for Wi-Fi.
2.2 Software Architecture
Software in an embedded system is very important. Even if we have all the hardware
components connected, in the absesnce of proper driving software the system will fail. All the
hardware modules are organized and controlled by software coded for the system. The coding
for this system is done by using Embedded C. Flow charts for the important software sections
is given below.
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International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
2.2.1 Sensor Section
2.2.2 Navigation
3. RESULTS
To check the working of the robot, it is placed in a room with obstacles created by wood
pieces. The robot gives alert when it comes with the obstacles and in the absence of
command from the user within the time limit it turns to one of the side according to the
situation. If the user cannot give a response within the time limit it switches to fully
automatic navigation mode. To check the gas situation LPG gas from cigar lighter is used.
The working of PIR for detecting the human body from the heat radiation is also tested. The
navigation system with semi automatic control proves that it can reach the destination with
less time than that of a fully automatic navigation in the same situation.
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International Journal of Emerging trends in Engineering and Development
ISSN 2249-6149
Issue 2, Vol.3 (April-2012)
4. CONCLUSION
This paper represents a design and implementation of a surveillance robot indented to use in
disaster sites and dangerous areas like nuclear plants where sending human beings are very
risky. This robot can detect the presence of humans, poisons gases, fire, sound etc. It can be
controlled by using a dual type wireless control system using
Wi-Fi. The tests prove that
the designed system can satisfy its goals within the budget limits.
ACKNOWLEDGMENT
This project could not have gotten completed without the help of several people. First
Dr.N.Rengarajan , whose guidance and assistance kept us focused on what was important.
Next Dr.A.MehabubBasha
helped us with general advice on the project. We would also
like to thank all the Electronics and Communication staff for all their aid.
REFERENCES
[1]. Momotaz Begum and Fakhri Karray Visual Attention for Robotic Cognition: A Survey,
IEEE Transactions On Autonomous Mental Development, VOL. 3, NO. 1, March 2011
[2]. Ming Gao, Kui Qian and Aiguo Song Design and Implementation of a Mini-Size Search
Robot, 2nd International Asia Conference on Automation and Robotics June 2010
[3]. Change Zheng Implementation of Reactive Control for a Miniature Surveillance Robot,
International Conference on Information Technology and Computer Science May 2009
[4]. G.e.H.W. Stone, “HANZBOT: A hazardous materials emergency response mobile robot,”
in Proceedings of IEEE International Conference on Robotics and Automation, Nice,
France, 1992
Sreejith K G Received B.Tech degree in Electronics and Communication Engineering from
Calicut University, Kerala, India in 2010. He is currently pursuing Master of Engineering
degree under Anna University, Tamilnadu, India in Embedded system technologies. His areas
of interest are Embedded Systems and Mobile Communication.
L Raja Received BE degree from KSR College of Technology under Anna University in
2001 and ME degree from Kongu Engineering College under Anna university in 2006. He is
currently pursuing his Ph.D under Anna University. His research area is Wireless networks
and his areas of interest are Wireless networks, Computer networks and Neural networks.
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