The document presents a project titled 'Intelligent Wheelchair for Handicapped Persons' undertaken by students of the American International University-Bangladesh to fulfill their degree requirements in Electrical and Electronic Engineering. The project focuses on developing a smart wheelchair equipped with features like obstacle detection, crack sensing, and voice control, aimed at enhancing the mobility and safety of handicapped individuals. It includes acknowledgments, methodologies, theoretical background, simulations, and discussions regarding the implementation and future scope of the project.

1. © Faculty of Engineering, American International University-Bangladesh (AIUB) i
INTILLEGENT WHEELCHAIR FOR HANDICAPPED
PERSONS
A Project Submitted
By
1. Shawon, SamsulIslam ID: 13-23289-1
2. Haque, MD. Anamul ID: 13-23212-1
3. Marzan, Mahmodul Hasan ID: 13-23146-1
4. Alam, Md Samiul ID: 13-23140-1
Under the Supervision of
Tajbia Karim
Faculty
American International University - Bangladesh
Department of
Electrical and Electronic Engineering
Faculty of Engineering
Summer Semester 2015-2016,
August, 2016
American International University - Bangladesh

2. © Faculty of Engineering, American International University-Bangladesh (AIUB)
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INTELLIGENT WHEELCHAIR FOR HANDICAPPED PERSONS
A project submitted to the Electrical and Electronic Engineering Department of the Engineering
Faculty, American International University - Bangladesh (AIUB) in partial fulfillment of the
requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering.
1. Shawon, SamsulIslam ID: 13-23289-1
2. Haque, MD. Anamul ID: 13-23212-1
3. Marzan, Mahmodul Hasan ID: 13-23146-1
4. Alam, Md Samiul ID: 13-23140-1
Department of
Electrical and Electronic Engineering
Faculty of Engineering
Summer Semester2015-2016,
August, 2016
American International University - Bangladesh

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DECLARATION
This is to certify that this project is our original work. No part of this work has been submitted
elsewhere partially or fully for the award of any other degree or diploma. Any material reproduced in
this project has been properly acknowledged.
Students’ names & Signatures
1. Shawon, Samsul Islam
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2. Haque, MD. Anamul
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
3. Marzan, Mahmodul Hasan
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
4. Alam, Md Samiul
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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APPROVAL
The Project titled “INTILLIGENT WHEELCHAIR FOR HANDICAPPED PERSONS” has been
submitted to the following respected members of the Board of Examiners of the Faculty of
Engineering in partial fulfillment of the requirements for the degree of Bachelor of Electrical and
Electronic Engineering on August, 2016 by the following students and has been accepted as
satisfactory.
1. Shawon, Samsul Islam ID: 13-23289-1
2. Haque, MD. Anamul ID: 13-23212-1
3. Marzan, Mahmodul Hasan ID: 13-23146-1
4. Alam, Md Samiul ID: 13-23140-1
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Supervisor
Tajbia Karim
Faculty
Faculty of Engineering
American International University-
Bangladesh
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Prof. Dr. ABM Siddique Hossain
Dean
Faculty of Engineering
American International University-
Bangladesh
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
External Supervisor
Dr. Mohammad Nasir Uddin,
Assistant Professor
Faculty of Engineering
American International University-
Bangladesh
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
Dr. Carmen Z. Lamagna
Vice Chancellor
American International University-
Bangladesh

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ACKNOWLEDGEMENT
We would like to express our greatest gratitude to the people who helped and supported us throughout
the project. We are grateful to Ms. Tajbia Karim who not only supervised our project but also
encouraged and challenged us throughout our academic program, never accepting less than our best
effort.
We are sure it would have been impossible without her help. Besides we would like thank our
honorable vice-chancellor Dr. Carmen. Z. Lamagna, Faculty of Engineering, American International
University Bangladesh (AIUB) who gave us this golden opportunity to do this wonderful project on
this topic "Intelligent Wheelchair for Handicapped Persons". We came to learn many new things and
perform research works by this project.
For the encouragement and valuable advice to further improve the design, we are thankful to our
honorable external supervisor Dr. Mohammad Nasir Uddin, Assistant Professor, Department of
Electrical and Electronic Engineering, American International University-Bangladesh (AIUB).
A special thanks goes to Md. Arif Abdulla Samy, Lecturer of Prime Asia University to share his
valuable experience in the field of embedded systems with us.
At last but not the least we want to thank our parents and classmates who boosted us and appreciated
our work.
And above all we are grateful to the Almighty Allah, who made everything possible.
Thanks to all who helped us.
1. Shawon, Samsul Islam
2. Haque, Md. Anamul
3. Marzan, MoahmodulHasan
4. Alam, Md. Samiul

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TABLE OF CONTENTS
DECLARATION .....................................................................................................................................III
APPROVAL.............................................................................................................................................IV
ACKNOWLEDGEMENT ........................................................................................................................V
LIST OF FIGURES ....................................................................................................................................IX
LISTOF TABLES..................................................................................................................................XII
CHAPTER 1 .................................................................................................................................................1
THEORY......................................................................................................................................................1
1.1 Introduction......................................................................................................................................1
1.2 Historical Background .....................................................................................................................1
1.2.1 Earlier Research [1]...................................................................................................................... 1
1.2.2 Recent Research........................................................................................................................... 2
1.2.3 State of the Art Technology .......................................................................................................... 3
1.3 Future Scope of this Study...............................................................................................................4
1.3.1 Future Scopes .............................................................................................................................. 4
1.3.2 Recommendations ........................................................................................................................ 5
1.4 Limitation of the Study....................................................................................................................5
1.5 Advantage over Traditional Method................................................................................................5
1.6 Objective of this Work.....................................................................................................................6
1.6.1 Primary Objectives ....................................................................................................................... 6
1.6.2 Secondary Objectives ................................................................................................................... 6
1.7 Introduction to this Thesis ...............................................................................................................6
CHAPTER 2 .................................................................................................................................................7
THEORY......................................................................................................................................................7
2.1 Introduction......................................................................................................................................7
2.2 Theory..............................................................................................................................................7
2.2.1 Theoretical Analysis Of Android Control Wheelchair Movement .................................................... 7
2.2.2 Theoretical Analysis Of Android Control Voice Command Display................................................. 8
2.2.3 Theoretical Analysis Of Obstacle Sensing...................................................................................... 8
2.2.4 Theoretical Analysis Of Crack Sensing.......................................................................................... 9
2.2.5 Theoretical Analysis Of Living Being Sensing ..............................................................................10
2.2.6 Android Control Home Automation System..................................................................................11
2.3 Summary........................................................................................................................................12
CHAPTER 3 .............................................................................................................................................403
METHODOLOGY .......................................................................................................................................13
3.1 Introduction....................................................................................................................................13
3.2 Block Diagrams .............................................................................................................................13
3.2.1 Block diagram of Android Control Wheelchair and Home automation ............................................13
3.2.2 Block Diagram of Voice Commanded LCD Display and Living Being Sensing...............................14
3.2.3 Block Diagram of Obstacle Detection...........................................................................................14
3.2.4 Block Diagram of Crack/Hole Sensing..........................................................................................15
3.3 Methodology..................................................................................................................................15
3.3.1 Mechanism of Android Control Wheelchair ..................................................................................15

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3.3.2 Mechanism of Android Control Voice Commanded LCD Display ..................................................17
3.3.3 Mechanism Of Obstacle Sensing ..................................................................................................18
3.3.4 Mechanism of Crack Sensing .......................................................................................................20
3.3.5 Mechanism of Living Being Sensing ............................................................................................21
3.3.6 Mechanism of Android Home Automation....................................................................................21
3.4 Summary........................................................................................................................................23
CHAPTER 4 ...............................................................................................................................................24
ELABORATION OF COMPONENTS...............................................................................................................24
4.1 Introduction....................................................................................................................................24
4.2 Individual Part's Equipments .........................................................................................................24
4.2.1 Equipments of Android Control Wheelchair ..................................................................................24
4.2.2 Equipments of Voice Commanded LCD Display...........................................................................24
4.2.3 Equipments of Obstacle Sensing...................................................................................................24
4.2.4 Equipments of Crack Detection....................................................................................................25
4.2.5 Equipments of Living Being Sensing............................................................................................25
4.2.6 Equipments of Home Automation.................................................................................................25
4.3 Component's Description...............................................................................................................25
4.3.1 Arduino Uno...............................................................................................................................25
4.3.2 ATMega32 .................................................................................................................................30
4.3.3 Bluetooth Module........................................................................................................................32
4.3.4 LCD Display...............................................................................................................................33
4.3.5 Sonar:.........................................................................................................................................35
4.3.6 PIR.............................................................................................................................................36
4.3.7 IR Sensor....................................................................................................................................37
4.3.8 Relay..........................................................................................................................................38
4.3.9 Buzzer Module............................................................................................................................38
4.4 Summary........................................................................................................................................39
CHAPTER 5 ...............................................................................................................................................40
INDIVIDUAL SIMULATION OUTCOMES .......................................................................................................40
5.1 Introduction....................................................................................................................................40
5.2 Individual Simulation Outcomes ...................................................................................................40
5.2.1 Android Control Wheelchair ........................................................................................................40
5.2.2 Voice Commanded LCD Display .................................................................................................41
5.2.3 Obstacle Sensing.........................................................................................................................42
5.2.4 Crack Sensing .............................................................................................................................44
5.2.5 Living Being Sensing ..................................................................................................................44
5.2.6 Home Automation.......................................................................................................................45
5.3 Summary........................................................................................................................................46
CHAPTER 6 ...............................................................................................................................................47
HARDWARE IMPLEMENTATION OUTCOMES...............................................................................................47
6.1 Introduction....................................................................................................................................47
6.2 Hardware Prototype - Intelligent Wheelchair ...............................................................................47
6.3 Hardware Connections and Outcomes...........................................................................................48
6.3.1 Android Control Wheelchair Movement and Home Automation.....................................................48
6.3.2 Voice Command to LCD display and Living Being Sensing.........................................................522
6.3.3 Obstacle Sensing by Sonar...........................................................................................................53

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6.3.4 Crack Detection ..........................................................................................................................54
6.3.5 Connection of Pulse-width Modulator...........................................................................................54
6.4 Summary........................................................................................................................................55
CHAPTER 7 ...............................................................................................................................................56
DISCUSSIONS AND CONCLUSIONS.............................................................................................................56
7.1 Discussions ....................................................................................................................................56
7.2 Suggestion for Future Work ..........................................................................................................56
7.2.1 For Handicapped Persons.............................................................................................................56
7.2.2 For Transportation System...........................................................................................................56
7.3 Conclusions....................................................................................................................................57
REFERENCES ...........................................................................................................................................58
APPENDIX A.............................................................................................................................................62
CODE......................................................................................................................................................62

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LIST OF FIGURES
Fig 2.1: Sonar ranging principles. (a) Sonar configuration (b) Echo waveform (c) Range dot
placement (d) Sonar map.............................................................................................................8
Fig 2.2: Light absorption through IR sensor.............................................................................................9
Fig 2.3: Mechanism of PIR sensor..........................................................................................................11
Fig 2.4: The upper surface of PIR...........................................................................................................11
Fig 3.1: Block diagram of procedure of Android control wheelchair movement and home
automation system......................................................................................................................13
Fig 3.2: Block diagram of procedure of Android control voice directed display and living
being sensing...............................................................................................................................14
Fig 3.3: Block diagram of procedure of obstacle sensing using sonar...................................................14
Fig 3.4: Block diagram of procedure of crack/hole sensing using IR....................................................15
Fig 3.5: Flowchart of android control wheelchair operation..................................................................16
Fig 3.6: Flowchart of voice command LCD display…………..............................................................18
Fig 3.7: Flowchart of obstacle sensing operation...................................................................................19
Fig 3.8: Flowchart of crack/hole sensing operation...............................................................................20
Fig 3.9: Flowchart of living being sensing operation.............................................................................21
Fig 3.10: Flowchart of living android control home automation system................................................22
Fig 4.1: Arduino Uno..............................................................................................................................26
Fig 4.2: Structural review of Arduino Uno............................................................................................27
Fig 4.3: Arduino Uno Pin diagram ........................................................................................................27
Fig 4.4: ATmega32.................................................................................................................................30
Fig 4.5: Atmega32 pin diagram..............................................................................................................31
Fig 4.6: Bluetooth Module......................................................................................................................32
Fig 4.7: LCD display...............................................................................................................................33
Fig 4.8: Pin diagram of LCD .................................................................................................................34
Fig 4.9: Sonar........................................................................................................................../...............35
Fig 4.10: PIR ..........................................................................................................................................36

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Fig 4.11: Pin Structure of PIR ...............................................................................................................36
Fig 4.12: IR sensor .................................................................................................................................37
Fig 4.13: Relay .......................................................................................................................................38
Fig 4.14: Buzzer module ........................................................................................................................38
Fig 5.1: Simulation of android control wheelchair for forward direction...............................................40
Fig 5.2: Simulation of android control wheelchair for right direction……............................................41
Fig 5.3: Circuit connection of android control voice input for display..................................................41
Fig 5.4: Simulation of android control voice input for display..............................................................42
Fig 5.5: Circuit connection of obstacle sensing......................................................................................42
Fig 5.6: Simulation of obstacle sensing..................................................................................................43
Fig 5.7: Simulation of crack sensing.......................................................................................................44
Fig 5.8: Simulation of living being sensing............................................................................................44
Fig 5.9: Simulation of android control home automation (One Load is ON)….…................................45
Fig 5.10: Circuit connection of android control home automation (Another Load is ON)...............….45
Fig 6.1: Intelligent Wheelchair (Side and top view)...............................................................................47
Fig 6.2: Intelligent Wheelchair (Front and back view)..........................................................................48
Fig 6.3: Connection of android control wheelchair movement and home automation..........................48
Fig 6.4: Connection of android control wheelchair movement with android application.....................49
Fig 6.5: Wheelchair operating the right direction pin through relay......................................................49
Fig 6.6: Wheelchair operating the forward direction pin through relay.................................................50
Fig 6.7: Movement of wheelchair...........................................................................................................50
Fig 6.8: Connection of home automation with android application and the operation through
activating relay pin .....................................................................................................................51
Fig 6.9: Lamp and mobile charging process (AC load) are controlled by android software………......51
Fig 6.10: Connection of android control voice display and living being sensing..................................52
Fig 6.11: Connection of android application of voice command and sending voice to LCD................52
Fig 6.12: Voice showed in LCD.............................................................................................................53
Fig 6.13: Connection of obstacle sensing...............................................................................................53

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Fig 6.14: Obstacle sensed and distance showed in LCD by Sonar........................................................53
Fig 6.15: Connection of crack sensing...................................................................................................54
Fig 6.16: Figure of sensing hole/crack...................................................................................................54
Fig 6.17: Circuit connection of PWM to control the speed of wheelchair…….....................................55

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LIST OF TABLES
Table 4.1: Features of arduino uno ........................................................................................................26
Table 4.2: Notation of arduino uno ........................................................................................................28
Table 4.3: Pin description of LCD module.............................................................................................34
Table 4.4: Features of Bluetooth Module .............................................................................................35
Table 4.5: Features of PIR .....................................................................................................................37

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Chapter 1
Introduction
1.1 Introduction
Physical disability is a curse to human life. Idea of our project "The Intelligent Wheelchair for
Handicapped Persons" has occurred to help the handicapped persons. The fundamental operation of
the wheelchair is to facilitate handicapped person with safe movement. For ensuring the safety of
movement, obstacle sensing, crack detection and living being identification features have been
included. Additionally, a voice controlled LCD has been provided considering the case of auditory
disabled people. Access to control basic home appliances has also been offered.
1.2 Historical Background
The history expresses the previous development of smart wheelchairs by researchers. Some of them
are shown below:
1.2.1 Earlier Research [1]
In1992 an Automated-Guided Wheelchair was published by NEC Corporation, Japan. It uses
IR sensors to stop when obstacles detected in its path.
In 1993 a research was done in COACH French Atomic Energy Commission, France. It provides
obstacle avoidance and follows walls.
In 1994-2000 CCPWNS University of Notre Dame, U.S. a research shows that user can automatically
reproduce routes taught to system by manually driving wheelchair from starting point to goal point.
Then in 1996 CHARHM CDTA, Algeria published a paper in which wheelchair navigates
autonomously to location in environment based on internal map and Information from machine vision.
In 1989 INCH Yale University, U.S. Very early attempt that used small robot that drove like a
wheelchair. They used sonar to avoid obstacles and drop-offs.
In 1998-2003 Intelligent Wheelchair System Osaka University, has two cameras, one facing toward
user, second facing forward. User provides input to system with head gestures, interpreted by inward-
facing camera. Outward-facing camera tracks targets and allows user to control wheelchair with
gestures when out of wheelchair, shares navigation with user (obstacle avoidance). Intelligent
Wheelchair, University of Texas at Austin, U.S. 1998 used as test bed for research into spatial
representation and reasoning in 1999-2002 Hephaestus TRAC Labs, U.S. The research Provides

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obstacle avoidance. Compatible with multiple brands of wheelchairs and does not require any
modifications to underlying power wheelchair.
Luoson III National Chung Cheng University, Taiwan 1999-2000.It provides shared navigation
assistance (obstacle avoidance) using force-feedback joystick. Can also Follow autonomous service
robot to destination. MAid RIAKP, Germany 1998-2003. It has two operating modes: Narrow-Area
Navigation (NAN) and Wide-Area Navigation (WAN). In NAN, system knows starting position and
orientation and navigates to goal position and orientation. In WAN, system moves to goal destination
but also identifies (and avoids) moving objects in environment. Mister Ed IBM, U.S. 1990 Robot base
with chair on top. Groups of behaviors activated to achieve specific behaviors (door passage, wall
following, target tracking). NavChair University of Michigan, U.S. 1993-2002 prevents wheelchair
from colliding with obstacles. It can automatically choose between multiple tasks specific Operating
modes. NLPR Robotized Wheelchair Chinese Academy of Sciences, China 2000 uses machine vision
to identify landmarks for localization. Offers several operating modes, including wall following,
collision avoidances and autonomous navigation to point on map.
In 2002 CWA (Manual) National University of Singapore, Singapore made a research on it. It uses
dead reckoning to keep wheelchair on prescribed path. In that research Path can be defined with GUI
or by walkthrough.
1.2.2 Recent Research
Pei Jia, Huosheng H. Hu, Tao Lu, Kui Yuan, (2007) “Head gesture recognition for hands‐free control
of an intelligent wheelchair” paper presents a novel hands‐free control system for intelligent
wheelchairs (IWs) based on visual recognition of head gestures.[2]
Towards an Intelligent Wheelchair System for Users with Cerebral Palsy which was published in 12
January 2010 this paper describes and evaluates an intelligent wheelchair, adapted for users with
cognitive disabilities and mobility impairment. The study focuses on patients with cerebral palsy, one
of the most common disorders affecting muscle control and coordination, thereby impairing
movement. The wheelchair concept is an assistive device that allows the user to select arbitrary local
destinations through a tactile screen interface. [3]
A brain-actuated wheelchair: Asynchronous and non-invasive Brain–computer interfaces for
continuous control of robots. This was published on 14 July 2008. The main purpose of this
wheelchair was to assess the feasibility and robustness of an asynchronous and non-invasive EEG-
based Brain–Computer Interface (BCI) for continuous mental control of a wheelchair. [4]
Development of Smart Wheelchair System for a User with Severe Motor Impairment by the Faculty of
Electrical & Electronic Engineering, University Tun Hussein On Malaysia, 86400 Parit Raja

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BatuPahat, Malaysia Which was published on 25 August 2012.By this wheelchair users with severe
motor impairment may find it difficult to operate a wheelchair when they are in tight space (e.g.,
passing doorway) or when avoiding obstacles since they cannot command the wheelchair by means of
a conventional joystick. Here we propose a framework that can assist users to overcome such
circumstances using a hierarchical semi-autonomous control strategy.[5]
NEURAL NETWORK WITH VARIABLE TYPE CONNECTION WEIGHTS FOR
AUTONOMOUS OBSTACLE AVOIDANCE ON A PROTOTYPE OF SIX-WHEEL TYPE
INTELLIGENT WHEELCHAIR which was published on June 2006. In this paper, an assist method
for human operation of electric-powered Wheelchairs is studied. The purpose of this research is to
make powered wheelchairs intelligent and to realize a mobility aid for people, who find it difficult or
impossible to drive a conventional wheelchair. [6]
A perspective on intelligent devices and environments in medical rehabilitation by Human
Engineering Research Laboratories, Department of Veterans Affairs, Rehabilitation Research and
Development Service, VA Pittsburgh Healthcare System, United States and the paper was published in
25 September 2008, Available online 6 November 2008. Globally, the number of people older than 65
years is anticipated to double between 1997 and 2025, while at the same time the number of people
with disabilities is growing at a similar rate, which makes technical advances and social policies
critical to attain, prolong, and preserve quality of life. Recent advancements in technology, including
computation, robotics, machine learning, communication, and miniaturization of sensors have been
used primarily in manufacturing, military, space exploration, and entertainment. [7]
Wheelchair Driver Assistance and Intention Prediction using POMDPs by ARC Centre of Excellence
for Autonomous Systems, Mechatronics and Intelligent Systems Group, University of Technology
Sydney, NSW2007, Australia. The physical control systems of such wheelchair can be prohibitive for
some users; for example, people with severe tremors. Several assisted wheelchair platforms have been
developed in the past to assist such users. Algorithms that assist specific behaviors such as door -
passing, follow - corridor, or avoid - obstacles have been successful. Research has seen a move
towards systems that predict the users intentions, based on the users input. [8]
1.2.3 State of the Art Technology
The historical review represents regarding the various types of smart wheelchairs. Our
intelligent wheelchair represents something new from the conventional technological wheelchair. The
accumulation provides the identity regarding different helpful mechanism through our tasks. On
account to differentiate with conventional technology, we added home automation system which is
totally different then other creation. This innovative invention will provide a physically disabled
person with the option of controlling the home appliances by android mobile phone easily.

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1.3 Future Scope of this Study
Smart wheelchairs will remain fertile ground for technological research for many years to
come. Smart wheelchairs are excellent test beds for sensor research, particularly machine vision. Smart
wheelchairs also provide an opportunity to study human-machine interface, adaptive or shared control,
and novel input methods, such as voice control, EOG (Electro Oculogram). Furthermore, smart
wheelchairs will continue to serve as test beds for robot control architecture.
1.3.1 Future Scopes
New engineering developments offer opportunities to develop smart wheelchair
assistive technology that can improve the lives of many people who use wheelchairs.
In our work, we are designing tomorrow's intelligent wheelchairs; we developed a
multi function able intelligent wheelchair that is aware of its surroundings so that it
can assist its user in a variety of tasks. The goal of this intelligent wheelchair project
is to enhance an ordinary powered wheelchair using an android software for
movement, a display for communication, sensors to perceive the wheelchair's
surroundings, a PIR to detect living being, a IR sensor to detect crack, and a home
automation circuit to make the life more easier.
The future intelligent robotic wheelchair can learn the layout of its environment (hospital,
rehabilitation center, home, etc.) through a narrated, guided tour given by the user or the user's
caregivers. Subsequently, the wheelchair can move to any previously-named location under voice
command (e.g., "Take me to the cafeteria"). This technology is appropriate for people who have lost
mobility due to brain injury or the loss of limbs, but who retain speech. The technology can be
enhanced with Tongue Motion Driver to move the chair by the movement of tongue which will be
easier for totally paradise people. It can be modified by gesture technology or voice commanded
technology. The technology can also enhance safety for users modified by caterpillar tracks which can
be used through stairs. Again for the movement in outside this wheelchair can be built up with the
operation of GSM for perfect communication of the user with others. [9]

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1.3.2 Recommendations
This project works are very important for the handicapped people who are disabled to walk on
their own feet, elderly, auditory disabled persons or paralyzed people. So this work is recommended
for them.
1.4 Limitation of the Study
The limitation may happen in any types of working procedure. We have tried our best to
deduct the problems from our job. The speed of this chair be controlled obviously with further
development, again there front wheels are emotionally involved with a view to supporting in the case
of movement which makes a complicity while moving from one direction to other direction instantly.
This can also be developed by ensuring mechanical technology, at last at the time of rotation one
wheel is stopped according to our function. For this reason, the rotation angle is fixed. The rotation
angle can be adjusted by controlling the direction and speed of both the motors by further research. As
this design is assembled to exploit at home, there will no severe problem. Further development is
needed to exploit it to use it in road.
1.5 Advantage over Traditional Method
As the case of movement user can easily move with his/her sovereignty which is almost similar
to walk.
This wheelchair does not require hand motivated motion. Rather by using a android smart
phone with specific application, this wheelchair can be moved easily in the desired direction. The
power of the wheelchair may offer the user to provide excellent experience throughout the movement.
Handicapped people are quite sufferer to make a communication with others. Specially for the people
with auditory disability, we made the wheelchair with an Android control software based operation
system where the directions, messages or voice can be seen by the user easily. User can also use this
option for communication.
This chair has identification mechanism for the safety of handicapped people. The sensing
system of distance can make a user sure about the obstacle, identify the living being and crack on the
surface.
Sometimes the user can not be able to control the home appliances according to their wish. In
this case this wheel chair provides the home automation system as an extra ordinary function indeed.

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Enjoying the outdoors is usually the common activity new wheelchair users look forward to
doing the most. One can enjoy picnics with friends at the park, explore park trails, bird watch, capture
pictures of scenery and much more. One can go shopping at one's favorite stores, dine at restaurants,
travel, go to the movies, visit friends and family and much more. Wheelchairs provide the user with a
more active lifestyle that usually results in a happier, healthier more positive outlook on life.
1.6 Objective of this Work
The objective of the work is elaborating below:
1.6.1 Primary Objectives
The primary objective of this work is to make the life easier with better movement
technologies for the handicapped persons.
1.6.2 Secondary Objectives
To provide a strong detection of obstacle, crack, living being for sensing with different
purposes for the user and to build communication level and provide home automation
features for better life leading system are secondary objective of this project .
1.7 Introduction to this Thesis
This paper is introduced with historical proceedings regarding the invention of wheelchair.
The future work and objective are offered over this chapter. Chapter 2 provides about the
theoretical background on this project work. The functions and diverse mechanisms are articulated
along with theory as a part. Chapter 3 introduces about the block diagram of the efforts with
fundamental methodology. Chapter 4 makes a clear and detail perception about the used
component. Chapter 5 and 6 provides the perfect outcomes through simulation and hardware
implementation respectively with necessary elaboration. Finally chapter 7 concludes the book
with a liberated discussion.

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Chapter 2
Theory
2.1 Introduction
The intelligent wheelchair of this project consists of several features to stress-free the life of a
physically disabled person. Besides android control movement of wheelchair, obstacle, living being
and crack detecting features have been included for the safety of the disabled person. However the
home automation mechanism has been built for the easier life leading route. These diverse features
are based on miscellaneous theories. This chapter represents the theory behind the features of the
intelligent wheelchair of our project.
2.2 Theory
2.2.1 Theoretical Analysis of Android Control Wheelchair Movement
The main parts of this section are dc motor, arduino uno board and relay. DC motor is an
electrical device that converts direct current electrical power into mechanical power. The DC motors
that were used in this project were normal cycle motors. These motors operate using 12.53 DC. Thee
motors are perfect in size. In order to operate the process arduino board is responsible for the system's
input and output. Programmed codes are also responsible for the arduino. Arduino is an open source
electronics prototype platform based on flexible easy-to-use hardware and software. An important
feature of using arduino for this project is that it communicates with software running on a smart
phone. The two relays are connected to the outputs of the Arduino Board. The input of the Arduino is
connected to the Bluetooth module to take the orders from the mobile application. Two relays are
connected to one DC motor. The relay makes sense with the help of arduino voltage and run the
wheelchair with desired directions. Android software is connected to Bluetooth Module via Bluetooth
link. Bluetooth module which is connected to arduino receives character data from android application
and transmits those characters to arduino. Arduino in turn is directly connected for its DIRECTION
and BRAKING.

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2.2.2 Theoretical Analysis of Android Control Voice Command Display
Interfacing a LCD (Liquid Cristal Display) with arduino follows with the connection of RS pin
to digital pin 12, R/W pin to digital pin 11. Digital lines DB4, DB5, DB6 and DB7 are interfaced to
digital pins 5, 4, 3 and 2 of the Arduino. The 10K potentiometer is used for adjusting the contrast of
the display. 560 ohm resistor R1 limits the current through the back light LED. The arduino can be
powered through the external power jack provided on the board. +5V required in some other parts of
the circuit can be tapped from the 5V source on the arduino board. The arduino can be also powered
from the PC through the USB port. The voice is transmitted though a Bluetooth module from android
smart hone. The Bluetooth module is connected to 3.3V pin and GND pin of arduino. Again the TX
pin of Bluetooth pin is connected to RX of arduino and the RX pin of Bluetooth pin is connected to
TX pin of arduino. The character of the voice is transmitted and showed in 16×2 LCD which is
actually maintained by the programmed arduino.
2.2.3 Theoretical Analysis of Obstacle Sensing
Sonar or ultrasonic sensing uses propagation of acoustic energy at higher frequencies than
normal hearing to extract information from the environment. Sonar use their echoes to measure range
to an object. As the sound speed is known, the object range is proportional to the echo travel time.
Figure 2.1: Sonar ranging principles. (a) Sonar configuration (b) Echo waveform (c) Range dot
placement (d) Sonar map[10]

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A sonar transducer, T/R, acts as both the transmitter (T) of a probing acoustic pulse (P) and the
receiver of echoes (E). The echo travel time to, commonly called the time-of-flight (TOF)is measured
from the probing pulse transmission time. In this case the echo waveform is a replica of the probing
pulse, which usually consists of as many as 16 cycle sat the resonant frequency of the transducer. The
object range ro is computed from by using
ro =
𝑐𝑡𝑜
2
(2.1)
where c is the sound speed (343m/s at standard temperature and pressure). A sonar map is usually built
by rotating the sensor about the vertical axis, indicated by the orientation angle θ, through a series of
discrete angles separated by Δθ and placing sonar dots the corresponding ranges. [10]
2.2.4 Theoretical Analysis of Crack Sensing
The IR sensor emits light to the surface When the surface is not found or black surface is
detected, it senses because of absorbing the light. Again it will not sense because of reflection of light
when white surface is detected.
Figure 2.2: Light absorption through IR sensor [11]
IR transmitter and receiver also called photo diodes are used for sending and receiving light. IR
transmits infrared lights. In this project, when infrared rays falls on any surface, it’s reflected back and
caught by photodiode and generates some voltage changes. When IR light falls on black surface, light
is absorbed by the black surface and no rays reflect back, resultantly photo diode doesn't receive any
light or rays.[11] It will not sense either it finds any crack over the surface. As soon as it reaches the
crack, the sensor doesn’t receives the light and the comparator sends logic 0 to the microcontroller for
the left sensor. On getting this condition the microcontroller make the signal for safety.[11] The
sensors are mounted at front end of the chair at middle place. The sensor is designed to detect the light
reflecting from the platform on which it is finding the crack, hole sensors don’t get this light.

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Programmed Atmega32 is responsible to sense the LED with the observation of hole or crack in the
surface.
An IR sensor detects the IR radiation. There are different types of IR sensors which are used on
different types of the application. Some examples Proximity sensors (Used in Touch Screen phones
and Edge Avoiding Robots), contrast sensors (Used in Line Following Robots) and obstruction
counters/sensors (Used for counting goods and in Burglar Alarms).
Basically an IR sensor is consists of a pair of an IR LED and a photodiode. The IR LED emits
IR radiation, reception and/or intensity of reception of which by the photodiode dictates the output of
the sensor.[12]
Direct incidence
As like IR LED directly in front of the photodiode almost all the radiation emitted, reaches the
photodiode. This creates an invisible line of IR radiation between the IR LED and the photodiode. If
an opaque object is placed obstructing this line, the radiation will not reach the photodiode and will get
either reflected or absorbed by the obstructing object.[12]
Indirect Incidence
Black color absorbs all radiation, the white color reflects all radiation. By placing IR LED and the
photodiode side by side, close together, the radiation from the IR LED will get emitted straight in the
direction to which the IR LED is pointing towards.[12]
Reflective Surface
If the object is reflective then most of the radiation will get reflected by it, and will get incident on the
photodiode[12]
Non-reflective Surface
If the object is non-reflective, (Black or some other dark color), then most of the radiation will get
absorbed by it, and will not become incident on the photodiode.[12]
2.2.5 Theoretical Analysis of Living Being Sensing
The PIR sensor has two slots in it. When the sensor is idle, both slots detect the same amount
of IR, the ambient amount radiated from the room or walls or outdoors. When a warm body like a
human or animal passes by, it first intercepts one half of the PIR sensor which makes a positive
differential changes between the two halves. When the warm body leaves the sensing area, the reverse

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happens, whereby the sensor generates a negative differential change. These change pulses are what is
detected.
Figure 2.3: Mechanism of PIR sensor [13]
Fig 2.4: The upper surface of PIR [14]
Infrared is a category of electromagnetic radiation with a wavelength that ranges between
approximately 700 nm to 300 µm. It does not fall in the visible light spectrum but is emitted by all
living beings and objects. [15]
2.2.6 Android Control Home Automation System
Home automation involves introducing a degree of automatic control to certain sectors like
lighting, temperature control, security systems, garage doors, etc. The system would control the
appliances based on its configuration. It can also allow a user to control appliances from a remote
location. These appliances include lights, fans, air conditioners, television sets, security cameras,

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electronic doors, computer systems, audio/visual equipment, etc. This sector demonstrates a system
that can be integrated into a wheelchair and allows one to remotely control lights, fans, and turn on or
off any appliance that is plugged into a wall outlet. The system can be controlled via a Bluetooth and a
mobile phone. The Bluetooth module is connected to arduino where relay pin controls the loads by the
direction of user via mobile application.
2.3 Summary
The theoretical mechanisms have been accumulated to make a bright design of a smart wheelchair.
This wheelchair will provide the people about the simple outlooks because of the accumulation. The
theory ensures about the particular section's mechanism behind the outcomes and the whole process
has been done with the similarity with the theoretical scenarios.

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Chapter 3
Methodology
3.1 Introduction
This chapter represents the methodology regarding the different parts through this project.
According to our project work and accumulation of the features with the arduino uno is precisely
elaborated in block diagram section. Intelligent wheelchair is build with 3 sum up section. Where a
arduino uno is built up with joining of android control system of wheelchair movement and home
automation, second one is built up with the android control system of voice display and living being
sensing, third one with only obstacle sensing and finally microcontroller based crack sensing method.
3.2 Block Diagrams
Block diagrams of the different features of our project have been attached in this section.
3.2.1 Block diagram of Android Control Wheelchair and Home automation
Fig 3.1 : Block diagram of procedure of Android control wheelchair movement and home
automation system

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The Bluetooth module is responsible to sense the direction from android smart phone application. This
will be further response by connected and coded arduino makes a controlling scenario through the
connected control pins of relay which is connected to motor to control the movements of wheelchair as
directed.
For controlling the home appliances again Bluetooth module sense the power controlling direction via
android application and repeat the same procedure from the coded code.
3.2.2 Block Diagram of Voice Commanded LCD Display and Living Being Sensing
Fig 3.2 : Block diagram of procedure of Android control voice directed display and living
being sensing
The use of android application for sending the voice through the android application via connected
Bluetooth which is connected to arduino and to show that as massage LCD display is connected with
coded arduino.
To sense living being the PIR sensor is connected with the arduino and a buzzer module is
connected with the arduino to provide the signal.
3.2.3 Block Diagram of Obstacle Detection
Fig 3.3 : Block diagram of procedure of obstacle sensing using sonar

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Sonar sensor is connected with the arduino uno to detect the obstacle and sense with dimension. A
LCD is connected with the arduino to show the dimension clearly.
3.2.4 Block Diagram of Crack/Hole Sensing
Fig 3.4: Block diagram of procedure of crack/hole sensing using IR
IR sensor is connected with a microcontroller to detect the crack and to sense with a signal, a
LED is connected with the microcontroller.
3.3 Methodology
3.3.1 Mechanism of Android Control Wheelchair
The Android Mobile is used as input. The Application is developed on the Android platform.
When the user touches the virtual button at that time a string is passed that and then transmitted from
the transmission unit to the receiving section through the mobile phone's Bluetooth. It operates on 5V
supply and has clock cycle of 20MHz. Battery of 12.53 V is used to drive the wheelchair.
For forward movement the motors are moved forward. For left movement the left motor is
stopped and right motor in forward direction and for right movement the right motor is stopped and
left motors are moved in forward direction. The speed of motor is controlled by mechanism of PWM.

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Fig 3.5: Flowchart of android control wheelchair operation

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When the application is opened at that time a request is generated if the Bluetooth is not
turned on. Algorithms are-
 A connect virtual button is present which is used to connect the Android mobile phone
with the hardware Bluetooth HC-05 for wireless transmission of data.
 When the Bluetooth is switched on the application scans the input when the user
touches the virtual button.
 If the requirement is forward then all the dc motors are supplied with 5V and moved in
forward directions for linear movement.
 If the requirement is to turn left then the left dc motors are stopped and the right dc
motors are supplied with 5V and the wheelchair moves in left direction.
 If the requirement is to turn right then the right dc motors are stopped and the left dc
motors are supplied with 5V and the wheelchair moves in right direction.
 If the stop virtual button is touched then all the dc motors are stopped.
 When the person reaches his/her destination at that time the disconnect virtual button
needs to be touched so that the Bluetooth connection is turned off.
3.3.2 Mechanism of Android Control Voice Commanded LCD Display
The main mechanism of the project is to develop a LCD display with the message from the
users mobile. While the user sends the message from the mobile, the remote operation is achieved by
any smart-phone/Tablet etc., with Android OS based on voice operation. Several messages are shown
on the LCD which is built in code of arduino. The +5V operates the whole procedure. The Bluetooth
module is responsible to send the input direction through arduino board. The character shows in 16×2
LCD as the voice are taken by the android application.

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Fig 3.6: Flowchart of voice command LCD display
3.3.3 Mechanism of Obstacle Sensing
Obstacles can be defined as objects protruding sufficiently high from the ground or in front of
the patient. The procedure calculates the disparity to find the obstacle or anything indeed. Then it

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works with the built in formulas of centimeter and inches of code and calculate distance. The final
output as well as the distance of the obstacle, anything, corner or surface is showed via LCD display.
Fig 3.7: Flowchart of obstacle sensing operation

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3.3.4 Mechanism of Crack Sensing
The mechanism of the crack sensing is depends on IR sensor and programmed microcontroller
Atmega32. Led will glow a view to attracting the user's concentration by sensing any types of crack,
discontinuity or hole. Then there will be change of the IR sensor as a output which will be processed
by the programmed microcontroller. The output of IR sensor is analog. So microcontroller can not
access the generated information of IR sensor. Thus that value will be converted to a digital value
where the digital value is compared with a reference value. If ATmega32 microcontroller found the
reference value lower than output, microcontroller will send any signal. Atmega32 will send signal
when the reference value is greater than output.
Fig 3.8: Flowchart of crack/hole sensing operation

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3.3.5 Mechanism of Living Being Sensing
PIR has a “motion sensing” mechanism. When any living being walks or comes in front of it
then it finds the characteristics as the PIR sense the heat of blood A continuous light wave radar has
been created by this sensor. A arduino is coded to make sound when a living being found. The code is
also responsible to show the detection message through the mobile application of anrdoid smart phone.
A buzzer module is connected to sense the sound which is connected to arduino.
Fig 3.9: Flowchart of living being sensing operation
3.3.6 Mechanism of Android Home Automation
For too many purposes the home automation feature is needed. In our project works this
section is coded and powered through arduino and operated by android application. The software
sends the signal via Bluetooth module which makes an effect in relay pins thus the load (appliances)
can be controlled.

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Fig 3.10: Flowchart of living android control home automation system

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3.4 Summary
The methodology of each section generally maintains the device performance and code where
the actual functions and methods of each department satisfies. These device dependent mechanism
have been utilized by the code.

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Chapter 4
Elaboration of Components
4.1 Introduction
The components used in this project are accumulated as far as possible. The two arduino
boards are adjoined with four different sections of our project.
4.2 Individual Part's Equipments
The individual equipments of different sections of this project are mentioned.
4.2.1 Equipments of Android Control Wheelchair
 Arduino uno
 Relay
 Battery 12v 1 Amp
 Bluetooth module
 Android Application
4.2.2 Equipments of Voice Commanded LCD Display
 LCD display
 Arduino uno
 Bluetooth
4.2.3 Equipments of Obstacle Sensing
 LCD display
 Arduino uno

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 Sonar
4.2.4 Equipments of Crack Detection
 Atmega32
 IR sensor module
 LED
4.2.5 Equipments of Living Being Sensing
 Arduino uno
 PIR
 Buzzer
4.2.6 Equipments of Home Automation
 Arduino uno
 Relay
 Bluetooth module
4.3 Component's Description
4.3.1 Arduino Uno
The Arduino Uno is a microcontroller board based on the ATmega328. It has 14digital
input/output pins, 6 analog inputs, a 16 MHz crystal oscillator, a USB connection, a power jack, an
ICSP header, and a reset button.

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Fig 4.1 Arduino Uno [16]
Table 4.1 : Features of arduino uno [17]
Microcontroller ATmega328
Operating Voltage 5V
Input Voltage (recommended) 7-12V
Input Voltage (limits) 6-20V
Digital I/O Pins 14 (of which 6 provide PWM output)
Analog Input Pins 6
DC Current per I/O Pin 40 mA
DC Current for 3.3V Pin 50 mA
Flash Memory 32 KB of which 0.5 KB used by boot loader
SRAM 2 KB
EEPROM 1 KB
Clock Speed 16 MHz

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Fig 4.2 : Structural review of Arduino Uno [17]
Fig 4.3: Arduino Uno Pin diagram [17]

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Table 4.2: Notation of arduino uno [17]
ARDUINO PIN MICROCONTROLLER PIN
0 PD0(RXD)
1 PD1(TXD)
2 PD2(INT0)
3 PD3(INT1)
4 PD4
5 PD5
6 PD6
7 PD7
8 PB0
9 PB1
10 PB2(SS')
11 PB3(MSIO)
12 PB4(MISO)
13 PB5(SCK)
A0 PC0
A1 PC1
A2 PC2
A3 PC3
A4 PC4(SDA)
A5 PC5(SCL)
The power pins are as follows:
VIN: The input voltage to the Arduino board when it's using an external power source (as opposed to 5
volts from the USB connection or other regulated power sources.
5V: The regulated power supply used to power the microcontroller and other components on the
board. This can come either from VIN via an on-board regulator, or be supplied by USB or another
regulated 5V supply.
3V 3A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
GND. Ground pins.

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Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(),
digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a
maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In
addition, some pins have specialized functions:
Serial: 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data. These pins are
connected to the corresponding pins of the ATmega8U2 USB-to-TTL Serial chip.
External Interrupts: 2 and 3. These pins can be configured to trigger an interrupt on a low value, a
rising or falling edge, or a change in value.
PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.
SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication, which,
although provided by the underlying hardware, is not currently included in the Arduino language.
LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is
on, when the pin is LOW, it's off. The Uno has 6 analog inputs, each of which provides 10 bits of
resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it
possible to change the upper end of their range using the AREF pin and the analog Reference ()
function. Additionally, some pins have specialized functionality:
I2C: 4 (SDA) and 5 (SCL). Support I2C (TWI) communication using the Wire library. There are a
couple of other pins on the board:
AREF: Reference voltage for the analog inputs. Used with analog Reference ().
Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields
which block the one on the board. The Arduino Uno has a number of facilities for communicating with
a computer, another Arduino, or other microcontrollers. The ATmega328 provides UART TTL (5V)
serial communication, which is available on digital pins 0 (RX) and 1 (TX). An ATmega8U2 on the
board channels this serial communication over USB and appears as a virtual com port to software on
the computer. The '8U2 firmware uses the standard USB COM drivers, and no external driver is
needed. However, on Windows, an *.inf file is required.. The Arduino software includes a serial
monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX
LEDs on the board will flash when data is being transmitted via the USB-to serial chip and USB
connection to the computer (but not for serial communication on pins 0 and 1). A Software Serial
library allows for serial communication on any of the Uno's digital pins. The ATmega328 also support
I2C (TWI) and SPI communication.

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4.3.2 ATMega32
Fig 4.4 : ATmega32 [18]
In our days, there have been many advancement in the field of Electronics and many cutting
edge technologies are being developed every day, but still 8 bit microcontrollers have its own role in
the digital electronics market dominated by 16-32 & 64 bit digital devices. Although powerful
microcontrollers with higher processing capabilities exist in the market, 8bit microcontrollers still hold
its value because of their easy-to-understand-operation, very much high popularity, ability to simplify
a digital circuit, low cost compared to features offered, addition of many new features in a single IC
and interest of manufacturers and consumers. The features of this microcontroller are-
 High-performance
 Low-power AVR 8-bit Microcontroller
 Static Operation
 32 x 8 General Purpose Working Registers
 On-chip 2-cycle Multiplier
 Non-Volatile Program and Data Memories
 Optional Boot Code Section with Independent Lock Bits
 1024 Bytes EEPROM
 32k Bytes of In-System Self-Programmable Flash
 2K Bytes Internal SRAM
 On-chip Analog Comparator
 Master/Slave SPI Serial Interface
 Programmable Watchdog Timer with Separate On-chip Oscillator
 8-channel, 10-bit ADC

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 Programmable Serial USART
 Internal Calibrated RC Oscillator
 32 Programmable I/O Lines
 4.5-5.5V for ATmega32
 0-16MHz for ATmega32
 Power-down Mode: < 1µA
PIN count: Atmega32 has got 40 pins. Two for Power (pin no.10: +5v, pin no. 11: ground),
two for oscillator (pin 12, 13), one for reset (pin 9), three for providing necessary power and
reference voltage to its internal ADC, and 32 (4×8) I/O pins.
About I/O pins: ATmega32 is capable of handling analogue inputs. Port A can be used as
either DIGITAL I/O Lines or each individual pin can be used as a single input channel to the internal
ADC of ATmega32, plus a pair of pins AREF, AVCC & GND together can make an ADC channel.
No pins can perform and serve for two purposes (for an example: Port A pins cannot work as a
Digital I/O pin while the Internal ADC is activated) at the same time.
Digital I/O pins: ATmega32 has 32 pins (4portsx8pins) configurable as Digital I/O pins.
Timers: 3 Inbuilt timer/counters, two 8 bit (timer0, timer2) and one 16 bit (timer1).
ADC: It has one successive approximation type ADC in which total 8 single channels are selectable.
Reference is selectable, either an external reference can be used or the internal 2.56V reference can
be brought into action. There external reference can be connected to the AREF pin.
Fig 4.5 : Atmega32 pin diagram [19]

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Analog comparator: On-chip analog comparator is available. An interrupt is assigned for
different comparison result obtained from the inputs.
External Interrupt: 3External interrupt is accepted. Interrupt sense is configurable.
Memory: It has 32Kbytes of In-System Self-programmable Flash program memory, 1024
Bytes EEPROM, 2Kbytes Internal SRAM. Write/Erase Cycles: 10,000 Flash / 100,000 EEPROM.
Clock: It can run at a frequency from 1 to 16 MHz. Frequency can be obtained from external
Quartz Crystal, Ceramic crystal or an R-C network. Internal calibrated RC oscillator can also be used.
More Features: Up to 16 MIPS throughput at 16MHz. Most of the instruction executes in a
single cycle. Two cycle on-chip multiplication. 32 × 8 General Purpose Working Registers
Debug: JTAG boundary scan facilitates on chip debug.
Programming: Atmega32 can be programmed either by In-System Programming via Serial
peripheral interface or by Parallel programming. Programming via JTAG interface is also possible.
4.3.3 Bluetooth Module
Fig 4.6: Bluetooth Module [20]

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HC-05 module is an easy to use Bluetooth SPP (Serial Port Protocol) module, designed for
transparent wireless serial connection setup.
Typical -80dBm sensitivity
 Up to +4dBm RF transmit power
 Low Power 1.8V Operation ,1.8 to 3.6V I/O
 PIO control
 UART interface with programmable baud rate
 With integrated antenna
 With edge connector
The serial module PINs are given below-
1. PIO8 connects with LED. When the module is power on, LED will flicker. And the flicker
style will indicate which work mode is in using since different mode has
different flicker time interval.
2. PIO9 connects with LED. It indicates whether the connection is built or not. When the
Bluetooth serial is paired, the LED will be turned on. It means the connection is built successfully.
3. PIO11 is the work mode switch. When this PIN port is input high level, the work mode will
become order-response work mode. While this PIN port is input low level or suspended in air, the
work mode will become automatic connection work mode.
4. The module can be reset if it is re-powered since there is a reset circuit at the module.
4.3.4 LCD Display
Fig 4.7: LCD display [21]

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Features of LCD display are given below
• 5 x 8 dots with cursor
• Built-in controller (KS 0066 or Equivalent)
• + 5V power supply (Also available for + 3V)
• 1/16 duty cycle
• B/L to be driven by pin 1, pin 2 or pin 15, pin 16 or A.K (LED)
• N.V. optional for + 3V power supply
Fig 4.8: Pin diagram of LCD [22]
Table 4.3: Pin description of LCD module
Pin No Function Name
1 Ground (0V) Ground
2 Supply voltage; 5V (4.7V – 5.3V) Vcc
3 Contrast adjustment; through a variable resistor VEE
4 Selects command register when low; and data register when high Register Select
5 Low to write to the register; High to read from the register Read/write
6 Sends data to data pins when a high to low pulse is given Enable
7
8-bit data pins
DB0
8 DB1

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9 DB2
10 DB3
11 DB4
12 DB5
13 DB6
14 DB7
15 Backlight VCC (5V) Led+
16 Backlight Ground (0V) Led-
4.3.5 Sonar:
Fig 4.9 : Sonar [23]
Table 4.4 : Features of Bluetooth Module [23]
Power Supply +5V DC
Quiescent Current <2mA
Working Current 15mA
Effectual Angle <15°
Ranging Distance 2cm – 400 cm/1″ – 13ft
Resolution 0.3 cm
Measuring Angle 30 degree
Trigger Input Pulse width 10uS
Dimension 45mm x 20mm x 15mm

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.
VCC- Connects to 5V of positive voltage for power.
Trig- A pulse is sent here for the sensor to go into ranging mode for the object detection.
(INPUT)
Echo- The echo sends a signal back if an object has been detected or not. If a signal is
returned, an object has been detected. If not, no object has been detected. (OUTPUT)
GND- Completes electrical pathway of the power.
4.3.6 PIR
PIRs are basically made of a pyroelectric sensor which can detect levels of infrared radiation.
Fig 4.10: PIR [24]
Fig 4.11: Pin Structure of PIR [25]

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Table 4.5: Features of PIR [25]
Size Rectangular
Output Digital pulse high (3V) when triggered
(motion detected) digital low when idle (no
motion detected). Pulse lengths are
determined by resistors and capacitors on the
PCB and
differ from sensor to sensor.
Sensitivity range up to 20 feet (6 meters) 110° x 70° detection
range
Power supply 3V-9V input voltage, but 5V is ideal
4.3.7 IR Sensor
4.12: IR sensor [26]
An IR sensor is a device which detects IR radiation falling on it. It works in direct, indirect,
reflective and non-reflective surface.

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4.3.8 Relay
Fig 4.13: Relay [27]
A relay is a simple electromechanical switch made up of an electromagnet and a set of
contacts. Relays are found hidden in all sorts of devices.
Relays are amazingly simple devices. There are four parts in every relay:
 Electromagnet
 Armature that can be attracted by the electromagnet
 Spring
 Set of electrical contacts
4.3.9 Buzzer Module
Fig 4.14: Buzzer module [28]

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Buzzer is an integrated role in the structure of electronic transducers, DC voltage power
supply, wide used in computers, printers, copiers, alarms, electronic toys, automotive electronic
equipment, telephones, timers, etc. electronic products for sound devices.
4.4 Summary
For interfacing each component the pin diagrams and other features have been followed to justify the
function. These point to point connections regarding the working principal of every junction of
component are very much responsible behind the achievement of the outcomes.

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Chapter 5
Individual Simulation Outcomes
5.1 Introduction
Simulations are the perfect procedure to know about the belongings whether ideas implies exactly or
not. The Proteus has been used to identify the outcomes before the project work of hardware
implementation.
5.2 Individual Simulation Outcomes
Different parts of our project's simulation are given below:
5.2.1 Android Control Wheelchair
Fig 5.1: Simulation of android control wheelchair for forward direction

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Fig 5.2: Simulation of android control wheelchair for right direction
5.2.2 Voice Commanded LCD Display
Fig 5.3: Circuit connection of android control voice input for display

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Fig 5.4: Simulation of android control voice input for display
5.2.3 Obstacle Sensing
Fig 5.5: Circuit connection of obstacle sensing

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Fig 5.6: Simulation of obstacle sensing

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5.2.4 Crack Sensing
Fig 5.7: Simulation of crack sensing
5.2.5 Living Being Sensing
Fig 5.8: Simulation of living being sensing

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5.2.6 Home Automation
Fig 5.9: Simulation of android control home automation (One load is ON)
Fig 5.10: Circuit connection of android control home automation (Another load is ON)

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5.3 Summary
The simulation parts are done individually to verify the perfection of each destination. To reduce the
cost and keep simplicity we accumulate some parts during hardware implementation.

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Chapter 6
Hardware Implementation Outcomes
6.1 Introduction
This section introduces with the individual hardware implementation pictures and other processes. The
operations and achievement through the project work defines via the attached picture of the particular
findings indeed.
6.2 Hardware Prototype - Intelligent Wheelchair
Fig 6.1: Intelligent Wheelchair (Side and top view)

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Fig 6.2: Intelligent Wheelchair (Front and back view)
6.3 Hardware Connections and Outcomes
Individual outcomes are shown below:
6.3.1 Android Control Wheelchair Movement and Home Automation
Fig 6.3: Connection of android control wheelchair movement and home automation

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Fig 6.4: Connection of android control wheelchair movement with android application
Fig 6.5: Wheelchair operating the right direction pin through relay

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Fig 6.6: Wheelchair operating the forward direction pin through relay
Fig 6.7: Movement of wheelchair

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Fig 6.8: Connection of home automation with android application and the operation through
activating relay pin
Fig 6.9: Lamp and mobile charging process (AC loads) are controlled by android software

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6.3.2 Voice Command to LCD display and Living Being Sensing
Fig 6.10: Connection of android control voice display and living being sensing
Fig 6.11: Connection of android application for voice command and sending voice to LCD

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Fig 6.12: Voice showed in LCD
6.3.3 Obstacle sensing by Sonar
Fig 6.13: Connection of obstacle sensing
Fig 6.14: Obstacle sensed and distance showed in LCD by Sonar

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6.3.4 Crack Detection
Fig 6.15: Connection of crack sensing
Fig 6.16: Figure of sensing hole/crack

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6.3.5 Connection of Pulse-width Modulator
Fig 6.17: Circuit connection of PWM to control the speed of wheelchair
6.4 Summary
All the hardware results are verified with the fundamental mechanism.

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Chapter 7
Discussions and Conclusions
7.1 Discussions
The project shows the real implementation of an android control wheelchair. The main
objective of this study is developing a useable, low cost assistive robotic wheelchair to help physically
disabled persons to make their life independent. In this project we developed a robotic wheelchair with
an in-built programmed Arduino based on ATmega32 microcontroller. By controlling wheelchair, we
also add some additional feature like obstacle sensing, living being detecting, Home appliances
controlling. However, there are still many improvements to be made. In the future more safety features
like laser sensors will have to be implemented and also bring an improvement to the obstacle sensing
Ultrasonic sensor algorithm. These types of sensors have the purpose to shut-down the entire system in
case of imminent collision, but also to avoid obstacles. The entire processes of different methodology
are accumulated. The codes are mentioned in the Appendix part A.
7.2 Suggestion for Future Work
We are hopeful to make some future works that can be done with it to modify it with it's best
outcomes. Some suggestions of the possibilities of future works are given below:
7.2.1 For Handicapped Persons
This chair can be developed with the tongue motion driver for the movement of wheelchair.
Beside a heart beat sensing sensor can be set up for better records of the patient. The wheelchair is
used by old aged persons in maximum case. So an artificial injection of insulin machine can be set up
for the diabetic patient which will be too much helpful for the diabetic handicapped people.
7.2.2 For Transportation System
The technology can be enhanced by using of caterpillar tracks for the movement through stairs.
Again for the movement in outside this can be added with gear system and electricity consuming

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mechanism for reducing the cost. Wheelchair can be built up with the operation of GSM for perfect
communication of the user with others.
7.3 Conclusions
This bright and innovative design will help for the handicapped person along with reducing the
sophisticated life style of those types of patient. Our job will be too helpful for the users so far. For the
revolution obviously this chair has to be further developed and manufactured. The world will see the
continuous invention with pioneering Excellencies. We strongly believe that "Intelligent Wheelchair
for Handicapped Persons" will be one of them.

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REFERENCES
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[3]L. Montesano, M. Diaz, S. Bhaskar and J. Minguez, "Towards an Intelligent Wheelchair System for
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[9]"Intelligent Wheelchair Project at MIT", Rvsn.csail.mit.edu, 2016. [Online]. Available:
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[10]L. Kleeman and R. Kuc, "Sonar Sensing", Springer Handbook of Robotics, pp. 491-519, 2008.

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[11]"Edge Avoiding Robot using 8051 Microcontroller", Circuitdigest.com, 2016. [Online]. Available:
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[12]"How to build an IR Sensor » maxEmbedded", maxEmbedded, 2013. [Online]. Available:
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[13]"PIR Motion Sensor Tutorial", Instructables.com, 2016. [Online]. Available:
http://www.instructables.com/id/PIR-Motion-Sensor-Tutorial/. [Accessed: 09- Aug- 2016].
[14]"How PIRs Work | PIR Motion Sensor | Adafruit Learning System", Learn.adafruit.com, 2016.
[Online]. Available: https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/how-pirs-
work. [Accessed: 09- Aug- 2016].
[15]"Pir Sensor", Excite, 2016. [Online]. Available: http://www.excite.com/content/home-
security/sensor-detector/pir-sensor. [Accessed: 09- Aug- 2016].
[16]"Arduino UNO R3 USB Board", Zagrosrobotics.com, 2016. [Online]. Available:
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[17]S. Cheppali, "Arduino Boards-Pin mapping - iCircuit", iCircuit, 2014. [Online]. Available:
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[18]L. GmbH, "myAVR Microcontroller shop - ATMega32A-16PU", Shop.myavr.com, 2016.
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[20]"HC-05 Bluetooth Module – Robotech Shop", Robotechshop.com, 2016. [Online]. Available:
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[21] M. S. Minhas, "16×2 LCD Interfacing in 8bit mode," My journey with Microcontrollers and
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[28]"Digital Buzzer Module (SKU: DFR0032) - Robot Wiki", Dfrobot.com, 2016. [Online]. Available:
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Aug- 2016].

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Appendix A
CODE
Accumulated code of Android control wheelchair and home automation
int RELAY1 = 2;
int RELAY2 = 3;
int RELAY3 = 4;
int RELAY4 = 5;
int state;
int flag=0;
int stateStop=0;
void setup() {
pinMode(RELAY1, OUTPUT);
pinMode(RELAY2, OUTPUT);
pinMode(RELAY3, OUTPUT);
pinMode(RELAY4, OUTPUT);
Serial.begin(9600);
}
void loop() {
//if some date is sent, reads it and saves in state
if(Serial.available() > 0){
state = Serial.read();
flag=0;
}
// if the state is '1' the DC motor will go forward
if (state == 'A') {
digitalWrite(RELAY1,HIGH);

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if(flag == 0){
flag=1;
}
}
else if (state == 'a') {
digitalWrite(RELAY1,LOW);
if(flag == 0){
flag=1;
}
}
else if (state == 'B') {
digitalWrite(RELAY2,HIGH);
if(flag == 0){
flag=1;
}
}
else if (state == 'b') {
digitalWrite(RELAY2,LOW);
if(flag == 0){
flag=1;
}
}
else if (state == 'C') {
digitalWrite(RELAY2,HIGH);

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digitalWrite(RELAY1,HIGH);
if(flag == 0){
flag=1;
}
}
else if (state == 'c') {
digitalWrite(RELAY2,LOW);
digitalWrite(RELAY1,LOW);
if(flag == 0){
flag=1;
}
}
else if (state == '1') {
digitalWrite(RELAY3,HIGH);
digitalWrite(RELAY4,HIGH);
if(flag == 0){
flag=1;
}
}
else if (state == '2') {
digitalWrite(RELAY3,LOW);
digitalWrite(RELAY4,HIGH);
if(flag == 0){
flag=1;
}
}
// if the state is '3' the motor will Stop

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else if (state == '3' || stateStop == 1) {
digitalWrite(RELAY3,LOW);
digitalWrite(RELAY4,LOW);
if(flag == 0){
flag=1;
}
stateStop=0;
}
// if the state is '4' the motor will turn right
else if (state == '4') {
digitalWrite(RELAY3,HIGH);
digitalWrite(RELAY4,LOW);
if(flag == 0){
flag=1;
}
}
}
Code of Obstacle Sensing:
#include <LiquidCrystal.h>
LiquidCrystal lcd(11, 10, 5, 4, 3, 2);
const int trigPin = 8;
const int echoPin = 9;
long duration;
int distanceCm, distanceInch;
void setup() {

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lcd.begin(16,2);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
}
void loop() {
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distanceCm= duration*0.034/2;
distanceInch = duration*0.0133/2;
lcd.setCursor(0,0);
lcd.print("Distance: ");
lcd.print(distanceCm);
lcd.print(" cm");
delay(10);
lcd.setCursor(0,1);
lcd.print("Distance: ");
lcd.print(distanceInch);
lcd.print(" inch");
delay(10);
}
Accumulated Code of Voice Commanded LCD Display and PIR:
int inputPin = 9;
int pirState = LOW;

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int val = 0;
int pinSpeaker = 10;
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
String inData;
void setup() {
lcd.begin(16, 2);
lcd.print("Welcome!");
delay(3000);
lcd.clear();
pinMode(inputPin,INPUT);
pinMode(pinSpeaker, OUTPUT);
Serial.begin(9600);
}
void loop(){
int i=0;
char commandbuffer[100];
if(Serial.available()){
delay(100);
while( Serial.available() && i< 99) {
commandbuffer[i++] = Serial.read();
}
commandbuffer[i++]='0';
}
if(i>0)
Serial.println((char*)commandbuffer);
lcd.print((char*)commandbuffer);

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delay(1000);
lcd.clear();
val = digitalRead(inputPin);
if (val == HIGH) {
playTone(300, 160);
delay(150);
if (pirState == LOW) {
Serial.println("Motion detected!");
pirState = HIGH;
}
} else {
playTone(0, 0);
delay(300);
if (pirState == HIGH){
Serial.println("Motion ended!");
pirState = LOW;
}
}
}
void playTone(long duration, int freq) {
duration *= 1000;
int period = (1.0 / freq) * 1000000;
long elapsed_time = 0;
while (elapsed_time < duration) {
digitalWrite(pinSpeaker,HIGH);
delayMicroseconds(period / 2);
digitalWrite(pinSpeaker, LOW);
delayMicroseconds(period / 2);

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elapsed_time += (period);
}
}
}