SMART CANE FOR VISUALLY

IMPAIRED PEOPLE

ALWANI BT ANNAS

BACHELOR OF COMPUTER SCIENCE

(NETWORK SECURITY)

UNIVERSITI SULTAN ZAINAL ABIDIN

2017

SMART CANE FOR VISUALLY IMPAIRED PEOPLE

ALWANI BT ANNAS

Bachelor of Computer Science (Network Security)

Faculty of Informatics and Computing

Universiti Sultan Zainal Abidin, Terengganu, Malaysia

MAY 2017

i

DECLARATION

I hereby declare that this report is based on my original work except for quotations

and citations, which have been duly acknowledged. I also declare that it has not been

previously or concurrently submitted for any other degree at Universiti Sultan Zainal

Abidin or other institutions.

________________________________

Name : ..................................................

Date : ..................................................

ii

CONFIRMATION

This is to confirm that:

The research conducted and the writing of this report was under my supervison.

________________________________

Name : ..................................................

Date : ..................................................

iii

DEDICATION

I would like to dedicate my project to my beloved mother and father, who have taught

me that everyone is human, no matter what they look like, or where they come from. I

would also like to dedicate this to my friends, especially Syuhada, Farah Hana,

Amalin, and Farah Wahidah, who have inspired me to do many things this year and to

try things I have never dared to try this year. Not to forget my respectful supervisor,

Dr. Aznida Hayati, who help me through a lot in my journey of finishing this project.

iv

ABSTRACT

According to World Health Organization (WHO) there are 285 million people are

visually impaired worldwide. The amount consists of 39 million blind people and 246

million of low vision. Today, the problem we face is that people who are blind or have

low vision often have difficulty in navigating the outdoor environment. They often

need assistance for their movement. Hence, this project is to propose a solution for the

blind people in navigating outdoor environment. The project develops device that uses

ultrasonic sensor to sense object located around the device. This device will help user

to navigate the outdoor environment easily without the help of any assistance.

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ABSTRAK

Menurut Pertubuhan Kesihatan Sedunia (WHO) terdapat 285 juta orang yang cacat

penglihatan di seluruh dunia. jumlah yang terdiri daripada 39 juta orang buta dan

246 juta penglihatan rendah. Hari ini, masalah yang kita hadapi ialah bahawa orang-

orang yang buta atau mempunyai penglihatan sering mengalami kesukaran untuk

mengemudi persekitaran luaran. Mereka sering memerlukan bantuan untuk

pergerakan mereka. Oleh itu, projek ini adalah untuk mencadangkan penyelesaian

untuk rakyat buta dalam mengemudi persekitaran luar. Projek ini membangunkan

peranti yang menggunakan sensor ultrasonik untuk mengesan objek yang terletak di

sekitar peranti. Peranti ini akan membantu pengguna untuk mengemudi persekitaran

luar dengan mudah tanpa bantuan mana-mana bantuan.

vi

CONTENTS

PAGE

DECLARATION i

CONFIRMATION ii

DEDICATION iii

ABSTRACT iv

ABSTRAK v

CONTENTS vi

LIST OF TABLES viii

LIST OF FIGURES ix

CHAPTER I INTRODUCTION

1.1 Background 1

1.2 Problem statement 3

1.3 Objectives 3

1.4

1.5

Scopes

Limitation of Work

3

4

1.6 Expected Result 4

CHAPTER II LITERATURE REVIEW

2.1 Introduction 5

2.2 Ultrasonic Sensor 5

2.3 Related Works 6

CHAPTER III

METHODOLOGY

3.1 Introduction 12

3.2 Methodology Phases 12

3.2.1 Planning 13

3.2.2 Requirement Analysis 13

3.2.3 Design 14

3.2.4 Implementation 15

3.2.5 Testing 16

3.2.6 Deployment 16

3.3 Summary 16

vii

REFERENCES 17

viii

LIST OF TABLES

TABLE TITLE PAGE

2.3 First table in chapter 2 11

ix

LIST OF FIGURES

FIGURE TITLE PAGE

3.1 First figure in chapter 3 12

3.2.3 Second figure in chapter 3 14

1

CHAPTER I

INTRODUCTION

1.1 Background

There are many types of disabilities that are known in today’s world for

instance, physical disabilities, hearing-impaired, visually-impaired, and etc. Visually-

impaired people are the people that face the most risks compared to other disabilities.

The eyes are the main part of the body used by humans to avoid obstacles where it

performs automatic process with minimum cognitive effort. However, for the visually-

impaired, their vision needs to be substitute by either tactile sense or auditory.

According to Herman [1], one of the main problems of visually-impaired is that most

of these people have lost their physical integrity. They also do not have confidence in

themselves. This statement is proved by Bouvrie [2] in an experiment called “Project

Prakash”. This experiment tested blind people to fully utilize their brain to identify

sets of object.

According to World Health Organization (WHO) there are about 314 million

people are visually impaired worldwide. The amount consists of 45 million blind and

269 million of low vision. People of 50 years old and above are 82% of all blind. It is

said that 45 million visually impaired people depends on other human for navigation,

information dispensation, and ecological analysis. NES II (National Eye Survey)

conducted in 2014 in Malaysia, there are 216,000 became blind because of delays in

cataract surgery. It also caused 272,000 to be visually impaired. The second

commonest cause of blindness in Malaysia is diabetic eye disease where 10% blind,

and 6% with low vision. The third commonest cause of blindness would be glaucoma

where it caused 7% blind, and 2% with low vision.

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Hence, the increasing of visually-impaired people led to the increasing of

development of assistive technology (AT). Blind cane is the most common AT used

by visually-impaired. According to Mazo and Rodriguez [3], the blind cane is one of

the assisting tools for the visually-impaired and it is really important. Traditionally,

the uses of blind cane focus on two major topics which are grip and arc. When

outdoor, a person’s pace is faster and more regular. Making it the proper way to grip

the blind cane is the palm facing up at waist height with the index finger pointing

along the cane and the remaining fingers and thumb wrapping around the cane lightly.

While indoors, the grip of the cane change in such a way the user is holding a pencil

where the grip is upright at the sternum height and closer to the body. With both grips,

the elbow is kept tucked close to the body. On the other hand, the material that is use

in traditional blind cane originally is made out of wood. As time goes by, aluminium

replaced the wood. However, aluminium bends and breaks easily. Thus, fibre glass

and carbon fibre replaced both wood and aluminium. Although fibre glass has a

reasonably price but it is heavier than carbon fibre. However, fibre glass could bend

slightly but it can return to its original shape. On the contrary, carbon fibre is more

expensive than aluminium and fibre glass. Although carbon fibre is lighter, but it

cannot bend and break easily.

However, independencies for the visually-impaired cannot be offered by this

walking blind cane anymore. Hence, as we move forward towards the modern world,

so does the technologies. As we can see there are so much ATs that had been

developed throughout the yearssuch as Laser Cane, Mowat Sensor, Nav Belt, Sens

Cap, Tyflos, Nottingham Obstacle Detector, Path sounder, Embedded Glove, Binaural

Sonic Guide and the Smart Cane itself. Most of ATs appeared in the form of the

White Cane. The purpose of developing assistive technologies is to minimize

accidents involving visually-impaired people as many as possible. According to

Chang and Song [4], when visually-impaired people walk into new environment, it

will be difficult for them to memorize the location of the object or obstacle. However,

for Nav Belt [5] it is use at the waist which it can cause damage to the neural system.

As well as the Sens Cap [5] is put on the head of users. It also can cause damage to the

neural system. Hence, they are not suitable ATs to be used by the visually-impaired.

Any assistive tools need to have the requirement of which it must be usable, portable,

affordable, handful and safe.

3

1.2 Problem Statement

The visually-impaired people tend to have a problem where they cannot

navigate freely in an environment either known or unknown to them. The existing of

Smart Cane should aim to help each visually-impaired people to navigate through

their daily motion. The use of Smart Cane should be optimized for usable and

affordable enough that can be easily use by all the visually-impaired. However, the

current problem that we face today is that the visually-impaired people tend to have a

problem where they cannot navigate freely in an environment either known or

unknown to them. Hence, the visually-impaired people will not have confidence and

also lost their physical integrity in themselves. We also can see that because the

visually-impaired people cannot navigate properly, they need to adapt to the walking

cane that they are using instead of the walking cane itself needs to adapt with them.

Thus, using the Smart Cane which will navigate the users more accurately with the

use of ultrasonic sensor and vibration motor attached to the model can eliminate the

problem faced.

1.3 Objectives

1. To develop an assistive technology model to help visually-impaired people to

navigate in an indoor environment.

2. To implement the design of the model into the Smart Cane.

3. To test and evaluate whether the Smart Cane is fully functioned.

1.4 Scopes

This project focuses on two scopes:

1. Scopes of project which is to navigate in an indoor environment only.

2. Scopes of user which is the visually impaired people.

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1.5 Limitation of Work

This project is only limit in an indoor environment.

1.6 Expected Results

At the end of this project, the expected outcome from this project will be the

Smart Cane is fully developed, installed and functioned for users to use.

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CHAPTER II

LITERATURE REVIEW

2.1 Introduction

Literature review is a text of scholarly paper, which includes the current

knowledge include substantive findings, as well as theoretical and methodological

contribution to a related works. There are a few devices related to Smart Cane.

However, most of the device did not meet the requirement that needed by the users.

2.2 Ultrasonic Sensor

Ultrasonic sensors are self-contained solid-state devices designed for non-

contact sensing of solid and liquid objects [6]. Ultrasonic sensors are mainly use as a

measuring device where it can measure the distance to an object by using sound

waves. It measures distance by sending out a sound wave at a specific frequency and

listening for that sound to bounce back. It is possible to calculate the distance between

the sonar sensor and the object by measuring the elapsed time between the sound

wave being generated and the sound wave bounced back. Ultrasonic sensors can

reflect on a surface with any shape and it is not affected by physical contact makes it

more accurate compare to other sensors [7]. According to Han and Hahn [8], the

distance and the measurement of ultrasonic sensors are highly reliable where it also

provides the relatives errors and variances of measurements that are within a

reasonably small range.

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2.3 Related Works

Based on researches, there a few existing device found that help to assist

visually-impaired people. First, Smart Cane: Assistive Cane for Visually-impaired

People [9]. A research team designed a device called Smart Cane which helps

visually-impaired people to walk more confidently. This device communicates with

users through a voice alert and vibration which involves coding and physical

installation. The software that it uses is MPLAB which is an IDE for the Microchip

Technology Incorporated PICmicro microcontroller families. MPLAB is use to design

this device because it is the most compatible software for various kind of microchip

development. For the hardware requirement, this device uses ultrasonic sensors to

calculate the distance between obstacles and the device. It also uses microcontroller to

control the motion of the cane. Another hardware that is used is water detector to

detect the presence of water.

The design and development of this project is started with sensor selection

where a 40 kHz transmission ultrasound signal sensor is selected. Then, the design

process of the device is based on architecture. It is also placed with a circuit box

where the circuit is designed with a proto-board and printed circuit board (PCB). The

flowchart of the microcontroller is started with the ultrasonic input, continue to the

ADC process where the analogue data is converted to digital form. And when the

output is generated, the voice chip is reset. The process continue to the water sensor

input where if there is a presence of water, the buzzer is triggered. Finally, the buzzer

is reset. Next step of the design and development is where the development of PIC

configuration, voice alert, and circuit installation. Lastly, the device is tested for final

testing and the result for each analysis is represented as voice warning, result of

analysing the ultrasonic sensor, and result of analysing the water sensor.

However, there are a few problem arise in this project where the voice warning

might be confused because it might be too repetitive. The water sensor also has some

problem arise which is it can only detect water with 0.5 cm deep only and the water

sensor need to be wipe to stop the buzzer otherwise the water sensor buzzer cannot be

stopped.

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The second research is Smart Cane for Visually Impaired People [10]. This

project uses camera where the captured image is send to the PC. It also has a

controller to intimate the type obstacles and the distance between the obstacles and

device is determined through voice. There are a few software and hardware used to

design the device which is ultrasonic transmitter and receiver, amplifier frequency to

voltage converter, PIC controller, camera, image processing unit, PC, RS232, LCD

display, voice board and speaker.

The system design of this device is started by installing a 40 kHz ultrasonic

transmitter that is generated by the oscillator. Then the received frequency output

from the transmitter is amplified. There are two stage of inverting amplifier where the

first stage is to improve the signal and the second stage is to provide the analogue

signal which is applied to the driver. It also uses a capacitor that acts as a filter to

avoid distortion in the signal. If there are any obstacles, the buzzer will get alarmed

through the relay driver unit. Also the camera will capture the image of the obstacles

where it is connected to the image processing unit. The image will be scanned. The

image that has been scanned will be registered into the system and the information

about the image will be announced through the speaker with the help of voice board

and the controller. The LCD display is used to display information about the system

where it is connected to the PIC controller. RS232 is used for image processing unit to

communicate with the PIC controller where the data sent from the RS232 as a time-

series bits.

The software is developed in embedded C language and MATLAB algorithm.

The algorithm for this device is as follows:

START

Initialize CAMERA;

Initialize LCD;

Initialize RS232;

Initialize ultrasonic sensor;

Get the images;

Analyse the images through algorithm;

Register the images;

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Get the images;

Compare the images;

Get the distance from sensor unit;

If the distance = near initialize the buzzer;

Initialize the voice unit;

Announce the object type, distance and shape;

END

The resulted image capture is in many frames. There are original image,

accumulation array, raw image and raw image with line segments detected. The

purpose of this different illumination condition and codec is to generate different

voice signal for navigation.

The next research is Embedded Glove to Aid the Visually Impaired [5]. This

device is a bit different from the other device where it is a hand mounted tactile

obstacle avoidance system. It uses vibration mechanism feedback Sound Navigation

And Ranging (SONAR) by warning the users through vibration motors.

This device is basically a glove strapped to the wrist, embedded with ultrasonic

sensors, battery, microcontroller and vibrator motors. The energy consumption for the

whole system is controlled by a Photovoltaic (PV) panel where it is a very low power

consuming model that makes this device far more better than the others. The decision

of movement in the right direction is mainly made by the visually impaired person

wearing the glove. The possible range that can be detected by the ultrasonic sensor is

about 5 m. The feedback given once an obstacle is recognized is either through audio

or vibration. A tactile feedback is advised to use where the vibration mechanism of the

auditory signal can cause confusion to the user with the noise from the external

environment. Hence, the audio mechanism is used as an alternative mechanism.

The setup for this device is started with the proposed warning system which

includes ultrasonic modules (Module 1-3), PIC microcontroller (PIC16F628A), motor

driver (ULN 2003), vibrator motors (Vibrator 1-3) and a battery. First, three ultrasonic

modules and vibrator motors are used to detect obstacles from straight, left and right

direction. PIC16F628A act as a main controller to control the entire system and is

developed using Flowcode (v4.2.3.58) for PIC. Flowcode program allows easy

9

creation of programs by simply dragging and dropping icons. For the vibration motor,

a flat coin type coreless vibration motor is used due to its fast response, low operating

voltage range (between 2.7V and 3.3V), high speed at the rate of 1200 rpm, long life-

time and high performance for a silent paging signal for the warning system. The

speed of the vibration motor is controlled by PIC16F628A through Pulse Width

Modulation (PWM). ULN 2003 is use to drive the vibration motor successfully.

The result of this project can be seen through the analysis of performance of

HC-SR04 which is the ultrasonic modules.

The fourth research is Smart Cane [11]. This project uses vibration motor to

alert the user via haptic feedback. It also has an adjustable and ergonomic handle to

increase the comfort and ease of the cane. This device utilizes computer and sensory

technology to provide object detection capabilities and freedom of physical range. The

sensors and the motors are powered by an Arduino controller where it is one of the

easiest programmable electronic platforms for user to create prototypes.

An Arduino can make electronic input, output and sensory system functioned

with a breadboard and other piece of circuitry equipped to it. The Arduino uses C

based programming language which is very understandable to the user. Specifically

this device uses an Arduino Uno board. The sensors use in this device is

RadioShack® Ultrasonic Range Finder. This sensor sends out extremely high

frequency of sound wave.

The development of this device is started by making an adjustable handle and a

sensor that has been chosen is added to the handle. When obstacles are detected, a

specific distance is calculated by the sensor and it is send to the Arduino. Arduino can

access the data through the code release by the RadioShack® under GNU General

Public License. Then, an alert through vibration in the handle is send to the user. The

sensor can detect obstacles from the range of 3-400 cm and in the angle of 30°. For

the implementation of the feedback system, the vibration motor is housed in the

handle of the cane and is connected to the Arduino. Arduino will analyse data from

the ultrasonic sensor and the data is sent to the vibration motor in the form of

corresponding PWM duty cycle. The vibration motor will spin at different speed

according to the number of pulses. Certain delay between vibrations will read

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different distance of the obstacles. The greater the delay means the greater the

distance. The result of this project can be seen in the Testing the Accuracy of the

Ultrasonic graph.

However, this device has certain issues with the motors where the PWM was

difficult to achieve because the setup of the device involves resistor, transistor, diode

and various pins from the Arduino.

The last research that can be found is Smart Cane for Blinds [12]. This project

uses an intelligent shared control system where the device itself is a mobile platform

to ease the use of cane for users. This device consists of two independently wheels

that is steered by the users itself. It also consist of three basic control modules which

are the first basic module called goal seeking module where it is a continuous fuzzy

controller to travel the cane from one point to the other. The second basic module is a

discrete event controller to avoid the users from obstacles while walking which is

called obstacles avoidance. The third basic module which is called the human

intervention module is a discrete command from the users. The users interact with the

cane through a joystick where it can move in four different directions which is

straight, turn left, turn right and stop. All the modules stated is shared through a

decision-maker module to select only one action at one time. This device is simulated

using MATLAB/SIMULINK environment.

Embedded control system and an array ultrasonic distance is placed on top of

the platform of the cane. The sensors are assumed to be digital to detect the presence

of obstacles. As for the wheels, they are set by separate servos which allow the wheels

to turn independently. Encoders are fitted to the wheels to allow position and speed of

measurement.

The intelligent shared control system of this device exists in two modes which

are Unknown Environment Mode (UEM) and Known Environment Mode (KEM). For

UEM the control objectives are goal seeking and obstacle avoidance. For KEM the

goal seeking is the user responsibility. Three different basic control modules are

proposed to satisfy the control requirement in both UEM and KEM modes which had

been stated before. As for decision-maker module, it apply different rule for UEM and

KEM.

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The complete system is simulated using MATLAB 5.0/SIMULINK

environment. The fuzzy controller module which is the goal seeking module is

designed by the fuzzy logic toolbox. The end result of this project can be analysed

from the simulation gained.

Year Author Title Technique Description Similarities 2011 Mohd Helmy

Abd Wahab, Amirul A.

Talib, Herdawatie

A. Kadir, Ayob Johari,

A.Noraziah, Roslina M.

Sidek, Ariffin A. Mutalib

Smart Cane:

Assistive Cane for Visually-impaired People

MPLAB to develop the

source code of PIC

microcontroller

-Sensor selection -Design the architecture of the cane -Development of source code and physical installation

Uses Ultrasonic sensor

2013 Sankar Kumar S, Abarna J, Lavanya G,

Nithya Lakshmi S

Embedded Glove’ to Aid The Visually

Impaired

Pulse-echo method

-Sensor selection -Experimental setup -Distance measurement

Uses Ultrasonic sensor

2013 J.Ramprabu, Gowthaman.T

Smart Cane for Visually

Impaired People

Image Processing

method

-Consist of camera -Uses RS232 for Image Processing Unit to communicate with PIC controller unit

Uses Ultrasonic sensor

2014 Whitney Huang, Hunter

McNamara, Diana

Molodan, Amol Pasakar

Smart Cane

Pulse Width Modulation

-Sensors and motors are powered by Arduino controller -Uses Radishack Ultrasonic Range Finder sensor -Has an adjustable and ergonomic handle

Uses Ultrasonic sensor and Arduino

2014 Wahied Gharieb

Smart Cane for

Blinds

Decision-maker Module

-Consist of two independently wheels that can be steered -Consist of three basic module: goal seeking, obstacle avoidance, human intervention

Uses Ultrasonic sensor

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CHAPTER III

METHODOLOGY

3.1 Introduction

Methodology is the outline of the way a process or task will be carried out.

Thus, the development of this device is carried out by applying the methodology of

Smart Cane development. The development of this project is carried out by applying

the methodology of Agile Development. Figure below shows the iterative and

incremental model that is chosen to develop the project. This model is chose because a

project can be developed through repeated cycle which is iterative. The project can be

proceeds if there are any changes in the middle of the project. This model consists of

six phases which are planning, requirement, analysis and design, implementation,

testing and deployment.

Agile

Development

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3.2 Methodology Phases

3.2.1 Planning

The first step of the phase is planning where in this step included the

sensor selection for the cane. By reviewing from previous researches, the most

suitable sensor to use for this project is the 40kHz ultrasonic sensor (HC-

SR04) where it can at least produce 2cm diameter transmission by generating

2.4644 beams. The range of the ultrasonic sensor can go up to 1 meter and it is

free from audible noise that is below 20kHz and industrial noise which can go

up to MegaHertZ (MHz). This step also includes the development of Arduino

Uno and implemented coding from the arduino IDE. Planning is important to

develop the arduino board for the ultrasonic sensor to detect obstacles ahead.

The materials that is required for this project has been prepared.

Hardware

Arduino Uno

Mini bread board

Ultrasonic Sensor

Vibration Motor

Power cables

Toggle switch

Software

Arduino IDE

3.2.2 Requirement Analysis

In this step, a lot of information is gathered from literature review

which relates to Smart Cane, Ultrasonic Sensor and Arduino. The requirement

of hardware and software for this project has been listed in the planning step

for development. Some configurations for the arduino are filtered for the most

suitable distance to detect obstacles ahead.

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3.2.3 Design

This step is required so that the flow of this project will be successful.

In this step, a design of a circuit will be explained as shown as in figure below.

The circuit is powered by Arduino Uno microcontroller along with a

mini bread board for the ultrasonic sensor, a toggle switch for the on and off

function of the cane, vibration motor to send out the output to the user and a

power supply.

Here are the connections for each part:

Ultrasonic VCC to Arduino 5v.

Ultrasonic GND to Arduino GND.

Ultrasonic TRIG to Arduino D12.

Ultrasonic ECHO to Arduino D11.

Buzzer RED to Arduino D8.

Buzzer BLACK to Arduino GND.

Vibrator motor pin 1 to Arduino D7.

Vibrator motor pin 2 to Arduino GND

9 volt battery RED to Toggle switch pin 1.

9 volt battery BLACK to DC male power jack(-).

Toggle switch pin 2 to DC male power jack (+).

Vibration motor

Ultrasonic sensor

Arduino Uno Toggle switch

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3.2.4 Implementation

After the design has been develop, the configuration and the coding of

the arduino is implement. The circuit is installed. The coding for the vibration

includes delay between the vibrations to differentiate the distance of the

obstacles ahead. If else rules is used in the coding to differentiate the distances.

If there is any error or changes in the coding, it will be solved in this step. The

coding is as follows:

#define trigPin 13

#define echoPin 12

#define motor 7

void setup()

{ pinMode(trigPin, OUTPUT);

pinMode(echoPin, INPUT);

pinMode(motor, OUTPUT);

}

void loop()

{ long duration, distance;

digitalWrite(trigPin, LOW);

delayMicroseconds(2);

digitalWrite(trigPin, HIGH);

delayMicroseconds(10);

digitalWrite(trigPin, LOW);

duration = pulseIn(echoPin, HIGH);

distance = (duration/2) / 29.1;

if (distance >= 200 || distance <= 0) // Checking the distance,

you can change the value

{

digitalWrite(motor,HIGH);

}

else {

digitalWrite(motor,LOW);

}

delay(500);

}

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3.2.5 Testing

In this step the complete circuit will be test. If there is still error

occurred, it will be solved in this step. If there is any changes need to

implement, the project must start back at design step for revision flow.

3.2.6 Deployment

After the circuit has been completely installed without any errors, the

complete circuit will be attached to the cane.

3.3 Summary

In this chapter, the methodology of this project is explained. The flow of this

project followed the steps that needed to develop the Smart Cane. The requirement of

hardware and software is listed properly for the development of the Smart Cane.

17

REFERENCES

1. Herman N. J., “Deviance: The Symboli Interactionist Approach-The Making of

Blind Men”, Vol. 24, pp. 236-2 41, Dix Hills N.Y. General Hall, USA, 1999.

2. Bouvrie J. V., “Visual Object Concept Discovery: Observation in Congeniality

Blind Children, and a Computational Approach”, Elsevier Science, USA, 2007.

3. Mazo M. and Rodriguez F. J., “ Wheelchair for Physical Disable People With

Voice ,Ultrasonic and Infrared Control”, Autonomous Robots, Vol. 2, pp. 203-

224, 1998.

4. Chang C. C. and Song K. T., “Ultrasonic sensor data integrations and its

Application to environment Perception”, IEEE transaction on Ultrasonic, Vol. 1,

pp. 3-5, 2000.

5. S Sankar Kumar and others, ‘Embedded Glove ’ to Aid the Visually Impaired’,

International Journal of Electrical, Electronics and Data Communication, 1.1

(2013), 6–11.

6. Rockwell Automation.

7. A. Nurulnadwan, M.R. Nur-Hazwani, E. Erratul-Shela, and A.M. Ariffin, “The

Enhancement of Assistive Courseware for VisuallyImpaired Learners,” in Proc.

ITSIM. 2010.

8. Han Y. and Hahn H., “Localization and Classification of Target Surface Using 2

Pairs Of Ultrasonic Sensors”, IEEE International Conference on Robotic and

Automation, Detroit Michigan, pp. 1-2, 22 May 1999.

9. M Helmy Abd Wahab, Aa Talib, and Ha Kadir, ‘Smart Cane: Assistive Cane for

Visually-Impaired People’, IJCSI International Journal of Computer Science

Issues, 8.4 (2011), 21–27 <https://doi.org/1694-0814>.

10. J Ramprabu and T Gowthaman, ‘Smart Cane for Visually Impaired People’, 4.1

(2013), 24–28.

11. Diana Molodan, Rachel Rizzo, and Hunter Mcnamara, ‘Smart Cane’, 1–14.

12. W. GHARIEB and G. NAGIB, ‘Smart Cane for Blinds’, Proc. 9th Int. Conf. on

AI Applications, 2015, 253–62.