ii

NOVEL SENSOR FOR HUMAN LOCATION

DETECTION FOR SWING TYPES OF ELECTRICAL

APPLIANCES

BY

SULLEHA BINTI PARNIN

A dissertation submitted in fulfilment of the requirement for

the degree of Master of Science (Mechatronics Engineering)

Kulliyyah of Engineering

International Islamic University Malaysia

JUNE 2017

ii

ABSTRACT

The intervention of human to the appliances becoming less as the automated system is

rising. The key to the automatic devices is the use of a good sensor, transducer, actuator,

and excellent control system. Intelligent devices can be described as the device’s ability

in making the decision with respect to the event that is driven by the changing

environment. The current swinging appliances such as stand fan use no controller and

sensors for interacting with the environmental condition. This raises the issues of energy

wastage and inefficient angle rotation. In this dissertation, research entitles ‘novel

sensor for human location detection for swing types of electrical appliances’ is

developed. It outlined two separate sensory systems consist of LV-EZ1 Ultrasonic and

D6T-8L-06 Thermal sensors each. Systems can detect the human presence, and estimate

its location and direction which allow the swing appliances to direct itself to serve the

human. In a situation that we are unable to monitor the device at all time, the device is

expected to understand our needs in an intelligent way. It is possible to use two or more

Ultrasonic sensors to estimate the location of a subject. However, operating multiples

of Ultrasonic sensors at the close range in the same environment and overlapping beam-

path introduces interference. This research has overcome the instability of location

output due to Ultrasonic interference using Chaining and Average-Smoothing methods.

The result shows a noteworthy improvement to the Correct Output Response rate.

Subject stays from one meter-left of the Ultrasonic sensor array achieved a 99% Correct

Output Rate, recorded a 22% of improvement of sensor reading stability. The second

sensor used for detecting human location is Thermal sensor D6T-8L-06 which detecting

nothing but heat. This means, human, pets, and all the things that produce heat can be

detected too. This similarity of producing heat, however, will always have a significant

different due to diversity in properties, physical shape, size, and nature of a subject. The

pet’s fur act as an excellent insulator to Thermal radiation which difficult to be detected

by Thermal sensor. Experiments conducted on cats and human for a non-contact body

temperature shows that humans are always giving visible changes in temperature as

compared to cat. Even though it can be detected, the changes in temperature value is

too small and insignificant. Therefore, the average temperature changes of human is

used as a conditional set-point value in the program algorithm to detect any human

presence in the room. Upon the human presence, the location is estimated in terms of

angle. This angle is then become the current direction of the swing appliances. After

conducting a final test to the fans, Thermal sensor system proved to be more accurate

in detecting direction and human location compared to Ultrasonic sensory system.

Therefore, Thermal sensory system is proposed in this dissertation for cost effective

system.

iii

Arabخلاصة البحثABSTRACT IN ARABIC

الرئيس للاجهزة لات المعاصرة عندما يرتفع استخدام الاجهزة التي تشغل تلقائيا. والعنصريتناقص دور البشر مع الأو ناقل طاقة ومحرك ونظام تحكم متميز بشكل مناسب . يمكن وصف الاجهزة الذكية مجس التلقائية يتمثل في استخدام

لة المروحة فلا تشغل بأالحالية كة . أما الألات الدوَارة ي صلة بالبيئة المتغبخصوص حدث ذي بأنها ألة قادرة علي اتخاذ قرار هذه و وضعف زاوية الدوران . تولد عن ذلك مشكلة تبذير الطاقة لتعامل مع البيئة المتغية . اجل الأ مجسو أتحكم

) مكشاف من المجسات قادر علي تحديد موقع البشر". تم فيها إيجاد نوعينس " ابتكار حديث لمج :دراسة بعنوانال Thermal رارية( و) مكشاف السعة الح LV-EZ1 Ultrasonic sensorالموجات فوق السمعية

sensor D6T-8L-06 والذي بعده وجهته ىوإدراك مد في المكاني البشر التواجد(. كل نظام قادر على تحديدالات التي لا نستطيع متابعة سي الاجهزة علي الدوام الح. ففي يسمح بتغيي الاتجاه لخدمة الشخص المتواجد في المكان

للموجات فوق السمعية أو أكثر لتحديد يقة ذكية. يمكن استخدام مكشاف واحديتوقع من الجهاز استيعاب حاجاتنا بطر فى حيز بيئي. ومع هذا كله يتولد التداخل عندما يتم تشغيل عدد من مكشافات للموجات فوق السمعبة شخصموقع ال

شعة اتج عن تداخل الأضطراب المكاني النللايجاد حل إلى إ. توصلت الدراسة وءمتقاربة في حيز بيئي واحد مع شعاع ض( . أفادت النتيجة Average-Smoothing و Chaining ) تلطيف وتهدئة تسلسل المعدل للعمليةن طريق ع

س تم علي بعد متر يسار المجشخص بالمكان ال عند تواجدحيث ،حول تعزيز معدل استجابة الجهاز املموس اتقدمس الجهاز الادراكي. والمج ءفي قدرة ذكا 22% قق نجاحا ب ح يمر الذمن النتيجة الصحيحة الأ 99الحصول علي %

تحديد موقع البشر والحيوانات أنه بإمكانه يعني مما مكشاف السعة الحرارية . تحديد موقع البشر هوفي ستعمل المالثاني تلف حسب نصنيف ليفة بواسطته. فهذا التشابه الذي يحدث عند افراز الحرارة الدافئة بين جنس البشر والحيونات يخالأ

يصعب يالذممتاز للانبعاث الحراري ليفة مثلا يؤدي دور عازل الكائن الحي شكلا وحجما وطبيعة. ففرو الحيوانات الأرارة التي يفرزها القطط والبشر دون التقاطه عبر مكشاف الحرارة . ففي الدراسة التجريبية التي أجريت حول درجة الح

معدل تغي الحرارة في يمكن استخدام ن الفارق ضئيل وتافه. لذلك أبينهما رغم احوظمل اتغي قد عرفت حتكاك جسدي ايتم تحديد ،البشر كنقطة فاصلة في منهاج الجدولة الخوارزمية لتحديد وجود البشر فى الحيز المكاني. ففي حالة وجود البشر

خي للمراوح تم اعتماد مكشاف الحرارة أاختبار ءإجرا. فالزاوية هي التي تصبح ركنا لدوران الجهاز. وبعد وفق الزاويةالحيز لذلك، فإن هذا البحث يقترح بمكشاف الموجات فوق ا لسمعية . ةكأدق طريقة لتحديد اتجاه وجود البشر وموقعه مقارن

لأنه نظام فعال من حيث التكلفة.نظام مكشاف الحرارة

c

iv

APPROVAL PAGE

I certify that I have supervised and read this study and that in my opinion, it conforms

to acceptable standards of scholarly presentation and is fully adequate, in scope and

quality, as a dissertation for the degree of Master of Science (Mechatronics

Engineering).

…………………………………..

Md. Mozasser Rahman

Supervisor

I certify that I have read this study and that in my opinion it conforms to acceptable

standards of scholarly presentation and is fully adequate, in scope and quality, as a

dissertation for the degree of Master of Science (Mechatronics Engineering).

…………………………………..

Tanveer Saleh

Internal Examiner

…………………………………..

Ahmad Imran Ibrahim

Internal Examiner

This dissertation was submitted to the Department of Mechatronics Engineering and is

accepted as a fulfilment of the requirement for the degree of Master of Science

(Mechatronics Engineering).

…………………………………..

Syamsul Bahrin Abdul Hamid

Head, Department of

Mechatronics Engineering

This dissertation was submitted to the Kulliyyah of Engineering and is accepted as a

fulfilment of the requirement for the degree of Master of Science (Mechatronics

Engineering).

…………………………………..

Erry Yulian Triblas Adesta

Dean, Kulliyyah of Engineering

v

DECLARATION

I hereby declare that this dissertation is the result of my own investigations, except

where otherwise stated. I also declare that it has not been previously or concurrently

submitted as a whole for any other degrees at IIUM or other institutions.

Sulleha Binti Parnin

Signature ........................................................... Date .........................................

vi

INTERNATIONAL ISLAMIC UNIVERSITY MALAYSIA

DECLARATION OF COPYRIGHT AND AFFIRMATION OF

FAIR USE OF UNPUBLISHED RESEARCH

NOVEL SENSOR FOR HUMAN LOCATION DETECTION FOR

SWING TYPES OF ELECTRICAL APPLIANCES

I declare that the copyright holders of this dissertation are jointly owned by the

student and IIUM. Copyright © 2017 (Sulleha Binti Parnin) and International Islamic University Malaysia. All rights

reserved.

No part of this unpublished research may be reproduced, stored in a retrieval system,

or transmitted, in any form or by any means, electronic, mechanical, photocopying,

recording or otherwise without prior written permission of the copyright holder

except as provided below

1. Any material contained in or derived from this unpublished research

may be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies (print

or electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieved system

and supply copies of this unpublished research if requested by other

universities and research libraries.

By signing this form, I acknowledged that I have read and understand the IIUM

Intellectual Property Right and Commercialization policy.

Affirmed by Sulleha Binti Parnin

……..…………………….. ………………………..

Signature Date

vii

ACKNOWLEDGEMENTS

My most heartfelt acknowledgement and appreciation to many names and peoples.

Subsequently I shall write their names in this section and may this dissertation remind

me of their contributions.

My utmost pleasure to dedicate this work to my dear beloved mother, Martiah Maruthi,

and my siblings, who granted me the gift of their unwavering belief in my ability to

accomplish this goal: thank you for your support and patience for waiting.

I sincerely appreciate my supervisor, Associate Professor Dr Md. Mozasser Rahman for

his continuous support and excellent supervision from the beginning of the study to its

end.

I would also like to express my gratitude to Biomechatronic laboratories members,

Huda Azam, Rabiatul, Asmarani, Nazreen, Zakia, Shazana, and Rozaidi for their

encouragement and opinions. Laboratories technician, Br. Sahlan and Br. Nasrul, for

assisting me with tools and appliances needed. My classmates and roommates, I wish

all of you the very best in your research too.

For that, I will always remember and forever grateful, and this grateful is none but

belong to the most special one and only, The Almighty Allah. That I am not able to do

this alone without His Guidance.

viii

TABLE OF CONTENTS

Abstract ................................................................................................................... ii Abstract in Arabic .................................................................................................. iii

Approval Page ........................................................................................................ iv Declaration .............................................................................................................. v Acknowledgements ................................................................................................ vii Table of Contents ................................................................................................... viii List of Tables .......................................................................................................... x

List of Figures ......................................................................................................... xi List of Abbreviation ............................................................................................... xiv

List of Symbol ......................................................................................................... xv

CHAPTER ONE: INTRODUCTION .................................................................. 1 1.1 Background of The Study ....................................................................... 1

1.2 Problem Statement and Its Significance ................................................. 2 1.3 Research Objectives................................................................................ 3 1.4 Research Methodology ........................................................................... 3

1.5 Scope of Research................................................................................... 5 1.6 Organization of Dissertations ................................................................. 6

CHAPTER TWO : LITERATURE REVIEW .................................................... 8

2.1 Introduction............................................................................................. 8 2.2 Swing Types of Electrical Appliances and Its Applications .................. 8

2.3 Variation of Human Body Temperature ................................................. 12 2.3.1 Human Body Heat Transfer and Radiation in Indoor

Environment ................................................................................. 14

2.4 Human Presence and Location Sensing .................................................. 14 2.4.1 PIR Sensor..................................................................................... 15

2.4.2 Ultrasonic Sensor .......................................................................... 17 2.4.3 Thermal Sensor ............................................................................. 25

2.5 Patented Product ..................................................................................... 30

2.6 Chapter Summary ................................................................................... 33

CHAPTER THREE : DESIGN AND DEVELOPMENT OF SENSORY

SYSTEM ................................................................................................................. 35

3.1 Introduction............................................................................................. 35 3.2 Ultrasonic Sensory System ..................................................................... 36

3.2.1 Ultrasonic Sensor Maxsonar LV-EZ1........................................... 36 3.2.2 The Determination of Ultrasonic Sensor Beam Pattern Limit ...... 38 3.2.3 Overcoming Interference and The Design of Separator Length ... 43

3.2.4 Total Beam Path of Two Overlapping Ultrasonic Sensors ........... 46 3.2.5 Smoothing and Filter Data Using Averaging ................................ 47 3.2.6 Location of Detectance ................................................................. 48 3.2.7 Design Criteria .............................................................................. 52

3.2.8 Ultrasonic Sensory System Circuitry ............................................ 52

ix

3.2.9 Block Diagram and Flowchart ...................................................... 53 3.3 Thermal Sensory System ........................................................................ 55

3.3.1 MEMS Thermopile Sensor D6T-8L-06 ........................................ 55 3.3.2 Field of View (FOV) ..................................................................... 56 3.3.3 Changes in Temperature ............................................................... 59 3.3.4 Design of Sensor Arrangement ..................................................... 68 3.3.5 Algorithm Development ............................................................... 70

3.3.6 Determination of Angles and Direction ........................................ 72 3.3.7 Multiplexer Circuit ........................................................................ 75 3.3.8 Block Diagram and Flowchart ...................................................... 77

3.4 The Design of Swinging Mechanism ..................................................... 79 3.5 Chapter Summary ................................................................................... 83

CHAPTER FOUR: RESULT AND DISCUSSION ............................................ 84 4.1 Introduction............................................................................................. 84

4.2 Ultrasonic Sensory System ..................................................................... 84 4.2.1 Estimating Sensor Response and Data Stability ........................... 85 4.2.2 Advantages and disadvantages of cosine rule formulation ........... 94

4.3 Thermal Sensory System ........................................................................ 96

4.3.1 Single Human Detection (Following Mode) ................................. 96 4.3.2 Multiple Human Detection (Ranging Mode) ................................ 98

4.4 Performance Comparison of Ultrasonic and Thermal Sensory

System .................................................................................................... 100 4.5 Chapter Summary ................................................................................... 101

CHAPTER FIVE: RECOMMENDATION AND CONCLUSION ................... 102 5.1 Conclusion .............................................................................................. 102 5.2 Recommendation and Direction of Future Research ............................. 103

REFERENCES ....................................................................................................... 105

PUBLICATION ..................................................................................................... 108 APPENDIX A: Sample Scanning of Thermal Sensor ........................................ 109

APPENDIX B: Temperature Distribution of Human Body .............................. 111 APPENDIX C: Sensor Datasheets ........................................................................ 113

x

LIST OF TABLES

Page No.

Table 2.1 A review of human body temperatre 13

Table 2.2 Sensing stages 15

Table 2.3 Comparison table of Ultrasonic sensors 23

Table 2.4 Comparison table of Thermal sensor 30

Table 2.5 Patented product related to fan and/or swing appliances 31

Table 3.1 Beam angle for varying distance, D 42

Table 3.2 Position formularize to find distance D from US sensor 51

Table 3.3 Theoretical FOV ranging for one D6T-8L-06 58

Table 3.4 Changes in reading before and after the cat entering the FOV area 63

Table 3.5 Changes in body parts for front, side and back 66

Table 3.6 Spur Gear design parameters 80

Table 4.1 Expected Output response 86

Table 4.2 Result of percentage response for actual distance, 𝐷’ 89

Table 4.3 Result of response actual distance, 𝐷’ after reducing Interference 92

Table 4.4 The output of object location for US sensor 93

Table 4.5 Servo swinging range 94

Table 4.6 Performance comparison between Ultrasonic and Thermal sensor 100

xi

LIST OF FIGURES

Page No.

Figure 1.1 Flowchart of research methodology 4

Figure 2.1 Fan motor in condition of knob is pressed down 9

Figure 2.2 Usage of fan in indoor 10

Figure 2.3 Remote controls for air-conditioners 11

Figure 2.4 Variations of human body temperature. 12

Figure 2.5 PIR sensor exploded view 16

Figure 2.6 Beam pattern of Ultrasonic sensor 18

Figure 2.7 Beam pattern of Ultrasonic sensor 19

Figure 2.8 Setup measurement for Passive methods 20

Figure 2.9 Test set-up using mannequin in front of the robotics lamp 21

Figure 2.10 Result of Faltpihl, (2012) 22

Figure 2.11 Thermal sensor (a) Omron D6T (b) Devantech TPA81 26

Figure 2.12 Test setup for four Thermal sensors (Kuki et al., 2013) 27

Figure 2.13 Graph of normalized temperature (Honorato et al., 2008) 27

Figure 2.14 Thermal images of 40x60 thermopile array sensor 28

Figure 2.15 Signal resulted of using Daubechies wavelets 29

Figure 2.16 Operating Field of view (S.Parker el. al, 1999) 31

Figure 2.17 Patented system (Hui et al., 2014) 32

Figure 3.1 Conceptual design model of sensor integration to swing appliances 36

Figure 3.2 LV-Maxsonar EZ1 physical looks, pinouts, and dimensions 37

Figure 3.3 Ultrasonic transducer cross-sectional diagram 37

Figure 3.4 Simplified beam pattern shape 38

Figure 3.5 Experiment process of determining beam shape of US sensor 39

xii

Figure 3.6 Ultrasonic Sensor beam pattern (FOV) drawn to 10:5-cm 40

Figure 3.7 Distance of the object estimated 41

Figure 3.8 Beam pattern drawn to 1:95 cm scale for Maxsonar LV-EZ1 42

Figure 3.9 Experiment set up for determining optimum separation distance 44

Figure 3.10 Graph of firing time for different separation distance 45

Figure 3.11 Illustration of total beam pattern from combination of two US 47

Figure 3.12 Sensor set-up for two US sensors 49

Figure 3.13 Application of trigonometric function and cosine rule 50

Figure 3.14 Schematics diagram for Ultrasonic Sensory system 53

Figure 3.15 Block diagram of Ultrasonic sensor based fan system 54

Figure 3.16 Operation flowchart for US sensory system 55

Figure 3.17 Thermal sensor Omron D6T-8L-06. (Omron Corporation, 2012) 56

Figure 3.18 Pixel positioning of D6T-8L-06 57

Figure 3.19 Set-up for observing the changes in room temperature 60

Figure 3.20 Changes in room temperature over time of one hour 61

Figure 3.21 Experimental result for detecting Cat influence on Thermal Sensor 62

Figure 3.22 Thermal image of the cat 64

Figure 3.23 Sensor placement and FOV 69

Figure 3.24 Sensor casing design in top and isometric view 70

Figure 3.25 Flowchart for human presence detection 72

Figure 3.26 Total FOV angles for combination of two Thermal sensors 73

Figure 3.27 𝑇𝑋 arrangement for combination of two Thermal sensors 73

Figure 3.28 Angle assignation of each pixel location 74

Figure 3.29 Sides assignation for each pixel 75

Figure 3.30 PCA 9545 PCB’s board schematic 75

Figure 3.31 Back and front view of PCA 9545 Board 76

Figure 3.32 Schematic of Thermal sensory system 77

xiii

Figure 3.33 Thermopile sensory system program flow 78

Figure 3.34 Operation flowchart for Thermopile array sensor 79

Figure 3.35 Driving and driven gear for swing mechanism 80

Figure 3.36 Digital servo DS3109MG 81

Figure 3.37 Load and radius relationship for DS3109MG 82

Figure 3.38 Swing mechanism of the stand fan 82

Figure 4.1 Prototype of Ultrasonic sensor based stand fan 84

Figure 4.2 Response of sensor at D’=30-cm 87

Figure 4.3 Response of sensor at D’=100-cm 88

Figure 4.4 Response of sensor, D’=30-cm, after chaining is applied 90

Figure 4.5 Response, D’= 100 cm, after chaining is applied 91

Figure 4.6 Result for implementation of cosine rule 93

Figure 4.7 Thermal sensor based stand fan 96

Figure 4.8 Fan response to a subject facing FRONT of the sensor 97

Figure 4.9 Fan response for single subject in free-style motion 98

Figure 4.10 Fan response for multiple subject 99

xiv

LIST OF ABBREVIATION

AN Analog

COM Common Pin

CR Correct Output Response

FOV Field of View

GUI Graphical User Interface

IIC Inter Integrated Circuit

MEMS Microelectromechanical System

MR Miss Output Response

NC Normally Closed

NO Normally Open

OR Over Output Response

PIR Pyroelectric Infrared

SCL Serial Clock Line

SDA Serial Data Signal

STP Spatial Temporal Properties

TS Thermal Sensor

US Ultrasonic Sensor

xv

LIST OF SYMBOL

𝑎 Cross-sectional Area of One Pixel

𝐴 Cross-sectional Area of Total Pixel

𝑑 Separation Distance

𝑑𝑝 Diametral Pitch

𝐷’ Actual Right-Angle Distance 𝐷 Measured Right Angle Distance

𝐹 Load

F Face Width H Sensor Measured Distance

𝐻 Height of FOV

𝑚 Module 𝑛 Number of Pixel

𝑁 Number of Data

N Number of Teeth

𝑟 Gear Radius

𝑟𝑑𝑔 Radius of Driving Gear

𝑟 Radius of Driven Gear

∆𝑇𝑅 Change in Room Temperature

∆𝑇𝑅,𝐴𝑉𝐺 Average Change in Room Temperature

𝑇𝐵 Background Temperature

𝑇𝑂 Objective Temperature

𝑇𝑝 Body Part Temperature

∆𝑇𝑝 Average Body Part Temperature

𝑇𝑋 Pixel Temperature

𝑇𝑃𝐴𝑇 Surface Temperature of Thermal Sensor

𝑇𝑚𝑎𝑥 Maximum Temperature

𝑇 Motor Torque

𝑊𝑝𝑛 Total Width of FOV

𝑤𝑝𝑛 Width of FOV per Pixel

𝑋 Thermal Sensor Detection Distance

1

CHAPTER ONE

INTRODUCTION

1.1 BACKGROUND OF THE STUDY

In this dissertation, research entitle ‘novel sensor for human location detection for swing

types of electrical appliances’ is presented. Selected sensors used for detecting human

locations such as Ultrasonic, Thermal, and Pyroelectric are studied. The purpose of the

study is to design an effective and efficient sensory system that is able to estimate the

human location. The sensory system is then used for swing types of electrical

appliances.

Demand in swing appliances such as air cooler, stand fan and air conditioner is

forecasted to be increased yearly (Residential Consumption of Electricity, 2008).

Therefore, developing new types of swing mechanism for home appliances is important

to improve the living style of upcoming generation. Intelligent sensor integrated in the

swing appliances sense its surrounding condition for maintaining better user

experiences. Automation of human detection system is possible to develop with the help

of intelligent sensory system. Once the system recognized the presence of human, it

initiates the swinging mechanism to rotate with respect to the position of human.

This introductory chapter comprises of the research background, research

problems and its importance. Research problem answer why the standing fan is chosen

and the important of developing the sensory system for it. Then it followed by the

determination of objectives, research methodology flowchart and research scopes.

Towards the end of this chapter, research contribution, organisation and chapter

summary were also presented.

2

1.2 PROBLEM STATEMENT AND ITS SIGNIFICANCE

Stand fan is portable, cheaper and provide a thermal comfort to its user. The

significances of standing fan in comforting everyday life of human is the underlying

reason of its selection as the implementation for this research. Almost every household

own a swinging fan such as table fan, standing fan and wall fan. Not only a household,

but even more to the factories, schools, mosque, train stations, cafeteria, etc. This shows

that electrical appliances have a brighter future and significant in consumer’s needs.

The only things that need to be done is not just to manufacture and supply more

of its quantity, but rather to design and develop the appliances that is more intelligent.

Therefore, human can get benefit out of it. The current stand fan available in the market

raises issues of energy wastage, inefficient angle of rotation, and a non-autonomous

system. Fan is still operating even when there is nobody in its servicing spaces. User

therefore must use the fan when in needed and turn it off while finished manually. Its

work when the current is supplied and turn off when its disconnected with supply.

Furthermore, this hand operated appliances use no controller and sensors for interacting

with the environmental condition. Zakaria (2014) introduce using Pyroelectric sensor

to the fan to solve the problem. However, his system gives an unstable and false

detection signal. It became one major drawback for the system as it detects all kind of

motion regardless human presence. This shows that the implementation of Pyroelectric

sensor is not sufficient to detect the occupant presence for swing appliances.

As a solution to this problem, a novel sensor for human location detection for

swing type of electrical appliances (i.e. stand fan) have been developed separately using

two different types of sensors which are Ultrasonic array sensor and Thermal array

sensors. Therefore, swing appliances have better response upon human presence with

the integration of suitable sensors.

3

1.3 RESEARCH OBJECTIVES

The objectives of this research are:

1. To investigate suitable sensors and developing sensory systems for identifying

human presence and location.

2. To develop prototype of swing mechanism for each of the sensors system.

3. To develop algorithm and program for control system.

4. To evaluate performance of the prototypes.

1.4 RESEARCH METHODOLOGY

The measures used in this research methodology include a stage by stage process as

illustrated in Figure 1.1. Research starts with the defining stage, where it defines the

research objectives, problems, significant and scopes.

The second stage is an extensive literature survey analysis. Information or

theories from the related research regarding the human sensing method using

Ultrasonic, Pyroelectric, and Thermal sensors are the interest of the survey. Finally,

understanding the gaps among the past research allows to claim, clarify and as well as

to support the research problem statement.

Design and development stage come afterward where the system requirement

and specification is made. The system is divided into several subsystems (i.e. sensory

system, swing mechanism, and prototype development). Two selected sensors (i.e

Ultrasonic Maxsonar LV-EZ1 and Omron Thermal Sensor D6T-8L-06) for human

location detection were studied as separate sensory systems. Those sensors undergo

experiments to fulfil the design stage and finally integrated into a full system.

4

Figure 1.1 Flowchart of research methodology

The developed systems are then undergoing performance testing which graded

as either ‘poor’ or ‘excellent’ performances. Poor performance is when the system

requirement is not satisfied while excellent performance is vice versa. Based on the

result of the test, improvement will be made if needed which require the system to

undergo the looping event. Looping shows the robustness and at the same time can

improve the reliability and quality of the integrated system.

Each sensory system is required to detect the presence and location of human at

stationary and non-stationary with more than 60° FOV. Therefore, single sensor is

tested to record its actual limitation of FOV at the early stage of development. Later,

Start

Define

Literature

Survey

Design &

Development

Improve

Conclusion &

documentation

End

Excellent

Poor Performance

Testing

5

sensor is integrated in an array (i.e. more than one of the same kind connected in

parallel) which widen the total FOV. The arrangement of sensor position in the array is

carefully studied to maximized the detection area. Different method for the array

arrangement is used for US and TS since they operate in different way.

Performance of the sensory systems of both US and TS sensors are compared in

terms of Stand Fan efficiency or the ability of the fan to swing at the right direction

estimates. Finally, when the research achieved its objectives, conclusion and

documentation can be made.

1.5 SCOPE OF RESEARCH

Constraint and limitations are the most prominent elements that need to be taking into

considerations in the research. Time and budgets are the constraint parameters in this

research. Therefore, human sensing is limited to the stages of ‘Presence’ and ‘Locate’

only. The other three stages which are ‘Count’, ‘Track’ and ‘Identify’ are not included

in the research. This research also restricted to the field of home automation, intelligent

sensors, and smart appliances. Performance of the sensory system is limited to only be

applied for Stand Fan in an indoor environment. Stand Fan is chosen from among many

other swinging appliances due to its significance in the household, future demands, and

cost. Two prototype of Stand fan are developed with each use different types of sensor

for human sensing. Sensors are limited to human sensing sensor such as Ultrasonic and

Thermal sensor. The Stand fan controller is focused on controlling fan ON and OFF,

swing angle, and blade speed. Prototype of the Stand fan used the body of available fan

from the market, but with modified controller and swing mechanism. Rotation-types of

swing mechanism is developed rather than translation-types of swing mechanism since

Stand fan is chosen. Furthermore, sensor array is positioned at the fixed height of the

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column of Stand Fan and shall not be rotated. Rotating the sensor array need additional

actuator (i.e. servo motor) and require more power supply. Prototypes are tested in the

same indoor room with single and multiple occupants. The duration until the prototypes

completion is two years.

1.6 ORGANIZATION OF DISSERTATIONS

This dissertation comprises of six chapters and its brief descriptions are prearranged as

the following:

i. Chapter one is an introduction chapter which contains the background of

studies, problem statements and its significant, objectives, methodology, scopes,

and dissertation organizations.

ii. Chapter two discuss the current and past literature survey pertaining to the

mechanism of swing appliances, human detection methods using Thermal and

Ultrasonic sensors and literature analysis.

iii. Chapter three presented the Ultrasonic beam pattern and separation distance

limitations. Experiments on determining both (i.e. beam pattern and FOV) are

done and compared with the past research. The result from the experiment is

used for designing the sensors array placement distance from one another and

sensors casing. Later, Thermopile’s estimated Field of View (FOV) is

explained. The result from the experiment is used for designing the sensors array

placement distance from one another and sensors casing. Furthermore, the

torque specification and gears design for the swinging mechanism, block

diagram and flowchart of the system are also covered in this section.

iv. Chapter four discussed the result of the final integration of the swing prototype.

The performance of sensory system using Ultrasonic and Thermal sensors

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developed are compared in terms of advantages, disadvantages, efficiency, cost,

etc.

v. Chapter five conclude the research objectives achievements, limitations, and

countermeasure of the future works.

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CHAPTER TWO

LITERATURE REVIEW

2.1 INTRODUCTION

This chapter is divided into four sections which are mechanism of swinging appliances,

review of sensor in human sensing (i.e. PIR, US and TS), patented product, and

literature review analysis. The goal is to define the gap in the current research about the

sensory system used for human sensing in related literature. Swing mechanism is

reviewed at an early chapter which discuss the standard mechanism used for Stand fan

and Air-conditioner. Another section is added to review the variation of human body

temperature for determining the non-contact body temperature using Thermal sensor.

Technique used in human presence detection and localization using PIR, US, and TS

from past literatures is used as benchmark for future sensory system development. The

reviewed literature is summarized according to research year to observe the trend and

variations in the methods applied for human sensing.

2.2 SWING TYPES OF ELECTRICAL APPLIANCES AND ITS

APPLICATIONS

Standing fan, air conditioner, and air cooler are the examples of swing types of electrical

appliances. The utilization of swinging mechanism allows the appliance’s servicing

area to be widen. In oscillating mode, standing or pedestal fan normally swing to

predetermined angle repeatedly. Furthermore, standing fans generally do not complete

360o because full rotation will twist the wiring inside the stand body and link

mechanism (Zakaria, 2014). The blade of the fan is operated using one single phase AC

synchronous motor as shown in Figure 2.1.

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For a multiple speed of fan, voltage regulator is used to control the electricity

reaches the stator and rotor of the motor. The front shaft of the motor is connected to

the fan blades, while the other side of the shaft elongated and connected to mechanical

gears and link mechanism to enable the fan to swing. Oscillation is operated with a knob

on the top fan head housing and a gear-linkage mechanism. Different manufactures used

different means of connecting the knob gears to link such as spur and worm gears.

When the knob is being pressed, gear that is connected from the knob will be in

contact to another gear, allowing the shaft from back-end of motor to transmit the

rotational power, causing the head to oscillate side-to side with the steady speed. The

fan head swing in alternating direction with the help of four bar linkage that move in

the loop to cause the repetitive oscillation. Then, if the knob is pulled up, the oscillation

will be stopped immediately as there is no power transmitted to the gear.

Figure 2.1 Fan motor in condition of knob is pressed down and gears connected

(Bartlett, 2014).

Fans are widely used in many places. Its significancy is still relevant because of

its function as to regulate the air environment but not to change the state of the air. Thus,

it maintain the satisfaction of thermal comfort and equilibrium for the user in buildings