full thesis mobile robot location and monitoring system

8/18/2019 Full Thesis Mobile Robot Location and Monitoring System

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MOBILE ROBOT LOCATION AND MONITORING SYSTEM

AMANINA FARHANA BINTI AHMAD

Faculty of Mechanical Engineering

UNIVERSITI MALAYSIA PAHANG

Thesis submitted in partial fulfilment of the requirements for the award of the

degree of Bachelor of Mechanical Engineering

JUNE 2015


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SUPERVISOR’S DECLARATION

I hereby declare that I have checked this thesis and in my opinion, this thesis is adequate

in terms of scope and quality for the award of the degree of Bachelor of Mechanical

Engineering.

Signature :

Name of Supervisor : IR DR AKHTAR RAZUL BIN RAZALI

Position :Date :


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STUDENT’S DECLARATION

I hereby declare that the work in this thesis is my own except for quotations and

summaries which have been duly acknowledged. The thesis has not been accepted for

any degree and is not concurently submitted for award of other degree.

Signature :

Name : AMANINA FARHANA BINTI AHMAD

ID Number : MA11110

Date : 5 JUNE 2015


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ACKNOWLEDGEMENTS

I am grateful and would like to express my sincere gratitude to my supervisor Ir

Dr Akhtar Razul bin Razali for his germinal ideas, invaluable guidance, continuous

encouragement and constant support in making this research possible. He has always

impressed me with his outstanding professional conduct, and his belief that a Bachelor

program is only a start of a life-long learning experience. I appreciate his consistent

support from the first day I recieve the title of Final Year Project. I am truly grateful for

his progressive vision about my reserch in this project, his tolerance of my naïvemistakes, and his commitment to my future experiment result.

I acknowledge my sincere indebtedness and gratitude to my parents for their

love, dream and sacrifice throughout my life. I cannot find the appropriate words thatcould properly describe my appreciation for their devotion, support and faith in my

ability to attain my goals. Special thanks should be given to my committee members. I

would like to acknowledge their comments and suggestions, which was crucial for the

successful completion of this study.


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ABSTRACT

This thesis deals with latitude and longitude coordinate to determine distance accuracy

of Global Positioning System (GPS) in three different type. This three type of GPS are

GPS Mouse(connect to computer), Mobile GPS and Smartphone GPS. Global

Positioning System (GPS) is a space-based satellite navigation system that provideslocation and time information in all weather conditions, anywhere on or near the Earth

where there is an unobstructed line of sight to four or more GPS satellites. It isimportance of knowing the robot real time location. Without knowing the present

location, it is impossible for the robot to carry on task given to it. Also, it will be

difficult for the operator who operates the robot to mobilize and conducting any

mission. Due to the importance of knowing and understand robot positioning, location

identification for this problem. Tracking system by using satellite to track the robot

whereabouts is normally practiced globally. Satellite signal is used to track and reportthe robot position in real time. Therefore this system may be used as a location

detection and reporting device for this mobile robot project. In the result, GPS Mouseconnected on the computer is more accurate followed by Smartphone GPS and Mobile

GPS. This is because, Adopt SkyTraq 6 chipset with 65-channel help the Mouse GPSreceive more satellite channel compare to Mobile GPS and Smartphone GPS. Besides

that, present of GLONASS (Global Orbiting Navigation Satellite System) chip in theSmartphone help to acquire satellites up to 20% faster than devices that rely on GPS

alone. Finally, increase the number of GPS channel receiver will increase the accuracy

of GPS.


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ABSTRAK

Tesis ini berkaitan dengan bacaan kordinat latitud dan longitud bagi menentukan

ketepatan jarak terhadap tiga jenis GPS(Global Positioning System) yang berbeza. Tiga

jenis GPS tersebut adalah GPS Tetikus(disambungkan dengan komputer), GPS mudahalih dan GPS telefon pintar. Global Positioning System (GPS) adalah sistem navigasi

satelit yang menyediakan maklumat lokasi dan masa dalam semua keadaan cuaca, dimana sahaja di bumi ini jika terdapat empat atau lebih garis satelit GPS yang tidak

terhalang. Lokasi sebenar sebuah robot adalah penting untuk diketahui. Tanpa

mengetahui lokasi mereka, sebuah robot tidak mampu menjalankan tugas yang

diberikan kepadanya. Selain itu, pengendali sebuah robot juga sukar untuk

mengendalikan robot dalam menjalankan apa-apa misi kerana tidak mengetahui lokasi

sebenar robot tersebut. Sistem pengesanan dengan menggunakan satelit untuk mengesandi mana keduduksn robot kini sudah diamalkan di peringkat global. Isyarat satelit

digunakan untuk mengesan dan melaporkan kedudukan robot tersebut dalam masa yangsebenar. Oleh itu sistem ini boleh digunakan sebagai pengesanan lokasi dan peranti bagi

projek robot mudah alih ini. Melalui kajian yang dibuat sepanjang projek ini, GPStetikus yang disambungkan pada komputer adalah lebih tepat diikuti dengan GPS

telefon pintar dan GPS mudah alih. Ini adalah kerana, SkyTraq 6 chipset dengan 65saluran membantu GPS tetikus menerima lebih saluran satelit berbanding GPS mudah

alih dan GPS telefon pintar. Selain itu, kehadiran GLONASS(Global Orbiting

Navigation Satellite System) cip membantu talefon pintar untuk memperoleh 20%

satelit lebih cepat berbanding peranti yang bergantung kepada GPS sahaja. Akhir sekali,

semakin meningkat bilangan saluran GPS yang di terima akan meningkatkan ketepatanGPS.


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TABLE OF CONTENT

Page

SUPERVISOR’S DECLARATION ii

STUDENT’S DECLARATION iii

ACKNOWLEDGEMENTS iv

ABSTRACT v

ABSTRAK vi

TABLE OF CONTENTS vii

LIST OF TABLES xi

LIST OF FIGURES xii

LIST OF ABBREVIATIONS xiii

CHAPTER 1 INTRODUCTION

1.0 Introduction 1

1.1 Problem Statement 2

1.2 Objectives 2

1.3 Hypothesis 2

1.4 Scope Of The Project 2

CHAPTER 2 LITERATURE REVIEW

2.0 Introduction 3

2.1 Robot 3


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2.1.1 Type of Robotics

2.1.1.1 Outer Space2.1.1.2 The Intelligent Home

2.1.1.3 Exploration

2.1.1.4 Military Robots2.1.1.5 Farms

2.1.1.6 The Car Industry

2.1.1.7 Hospitals

2.1.2 Applications Of Robots

2.1.2.1 Industrial Robots

2.1.2.2 Medical robots

2.1.2.3 Military Robots

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5

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6

6

7

7

2.2 Mobile Robot 8

2.1.1

Type of Mobile Robot2.2.1.1 Land Based Wheeled Robot

2.2.1.2 Land Based Tracked Robot2.2.1.3 Land Based Legged Robot

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910

2.3 Mobile Robot And it's Issue 11

2.3.1 Location And Status Reporting

2.3.2 Range And Control

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2.4 Positioning Sensor 12

2.4.1 Odometry

2.4.2 Inertial Navigation2.4.3 Magnetic Compasses

2.4.4 Active Beacons

2.4.5 Global Positioning System (GPS)

2.4.6 Landmark Navigation

2.4.7 Map-Based Positioning

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2.5 The Global Positioning System (GPS) : Principles & Concepts 17

2.5.1 Global Positioning System (GPS) And Field

Navigation

2.5.2 Global Positioning System (GPS) Functions

2.5.3 Global Positioning System (GPS) Working Principle

2.5.3.1 Stage 1 The Satellites Act As Reference

Points

2.5.3.2 The Signal Travel Time Gives Distance

Information2.5.3.3 Three Distances Gives The Position

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21


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2.6 Positioning Coordinate and Reading 22

2.6.1 Latitude and Longitude, The True Coordinate System

2.6.2 Universal Transverse Mercator (UTM) Grid

Coordinate System2.6.3 UTM Measurements & Coordinates:

2.6.3.1 Eastings2.6.3.2 Northings

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CHAPTER 3 METHADOLOGY

3.0 Introduction 25

3.1 Equipment And Materials 26

3.1.1 Global Positioning System On Computer

3.1.2 Mobile Global Positioning System

3.1.3 Smartphone Global Positioning System

26

27

28

3.2 Procedure 29

3.2.1 GPS Setting3.2.2 GPS Response Testing

3.2.3

Accuracy Experiments3.2.4 Real Time Monitoring

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3030

CHAPTER 4 RESULTS AND DISCUSSIONS

4.0 Introduction 31

4.1 GPS Response Testing Result 31

4.2 Accuracy Experiment Result 31

4.2.1 Testing Place

4.2.1.1 Between Building4.2.1.2 Under the Tree

4.2.1.3 Open Space

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37

4.3 Average Distance Error 40

4.4 Discussions 41


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CHAPTER 5 CONCLUSION AND RECOMMENDATIONS

5.0 Conclusion 43

5.1 Recommendations 43

REFERENCES 44


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LIST OF TABLES

Table No. Title Page

4.1 Number of GPS channel receiver according to type of GPS 32

4.2 Latitute and longitude for between building at location 1 and itdistance error

33

4.3 Latitute and longitude for between building at location 2 and it

distance error

33


distance error

33


distance error

34

4.6 Latitute and longitude for under the tree at location 1 and itdistance error

35

4.7 Latitute and longitude for under the tree at location 2 and it

distance error

35


distance error

36


distance error

36

4.10 Latitute and longitude for open space at location 1 and itdistance error

37

4.11 Latitute and longitude for open space at location 2 and it

distance error

38

4.12 Latitute and longitude for open space at location 3 and itdistance error

38

4.13 Latitute and longitude for open space at location 4 and it

distance error

39

4.14 Average distance error for latitude and longitude between

building

40

4.15 Average distance error for latitude and longitude under the tree 40

4.16 Average distance error for latitude and longitude open space 41


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LIST OF FIGURES

Figure No. Title Page

2.1 Land based wheeled robot 8

2.2 Land based tracked robot 9

2.3 Land based legged robot 10

2.4 Global Positioning System (GPS) working principle 21

3.1 Mouse GPS 26

3.2 Mobile GPS 27

3.3 Smartphone GPS 28

4.1 (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4for between building

32

4.2 (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4

for under the tree

34

4.3 (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4

for open building

37


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LIST OF ABBREVIATIONS

EGNOS European Geostationary Navigation Overlay Service

GLONASS Global Orbiting Navigation Satellite System

GPS Global Positioning System

Lat Latitude

Long Longitude

UTM Universal Transverse Mercator

WAAS Wide Area Augmentation System


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CHAPTER 1

INTRODUCTION

1.0 Introduction

Mobile robot is surely an autonomous system that's to improve its motion in a

reaction to adjustments in its environment while performing a given task. Mobile robot

are segregated by different system into their capacity to generate developed

response.(Muhamad Ashadi B Abdul Rahman,2007) A number of systems are applied

in robotic and have interactionfor making the particular robot function. There are

several kinds of mobile robot which is handled by directed wired control, wiredcomputer control, infrared, radio frequency (RF), Bluetooth, and Wi-Fi (Wireless

Fidelity).

Some sort ofmobile robotis definitely anautomatic machine that'sable

tolocomotion. Mobile robots are capable to go around within theirsurroundings and are

certainly not fixedto a single actual one physical position. Mobile robots can also

beseen inmilitary, enforcement, industrial, and security settings. In comparison,

industrial robotsare generally more-or-less fixed, including things like of a gripper

assembly (or end effector) and also jointed arm (multi-linked manipulator), attached to a

fixed surface. Autonomous Rotorcraft Sniper System which is experimental robotic

weapons technique have being produced by the U.S. Army since 2005 is an example of

mobile robot use in military. (Phillip McKerrow, 1991)

It is importance of knowing the robot real time location. Without knowing the

present location, it is impossible for the robot to carry on task given to it. Also, it will be

difficult for the operator who operates the robot to mobilize and conducting any

mission. Due to the importance of knowing and understand robot positioning, location

identification for this problem. Tracking system by using satellite to track the robot

whereabouts is normally practiced globally. Satellite signal is used to track and report

the robot position in real time. Therefore this system may be used as a location

detection and reporting device for this mobile robot project.

This project thesis is focusing on programing the GPS system device which

provide a location information of the mobile robot. The Global Positioning System

http://en.wikipedia.org/wiki/Military_robothttp://en.wikipedia.org/wiki/Industrial_robotshttp://en.wikipedia.org/wiki/Robot_end_effectorhttp://en.wikipedia.org/wiki/Robot_end_effectorhttp://en.wikipedia.org/wiki/Jointed_armhttp://en.wikipedia.org/wiki/Autonomous_Rotorcraft_Sniper_Systemhttp://en.wikipedia.org/wiki/United_States_Armyhttp://en.wikipedia.org/wiki/United_States_Armyhttp://en.wikipedia.org/wiki/Autonomous_Rotorcraft_Sniper_Systemhttp://en.wikipedia.org/wiki/Jointed_armhttp://en.wikipedia.org/wiki/Robot_end_effectorhttp://en.wikipedia.org/wiki/Robot_end_effectorhttp://en.wikipedia.org/wiki/Industrial_robotshttp://en.wikipedia.org/wiki/Military_robot


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(GPS) is a space-based satellite routing system that givespositionand also period details

in every weather conditions, wherever on or evenclose to the Earth where there'sa

cleardistinctive line of sight to four or more GPS satellites. This chapter will story the

objective of the project, problem statement which need to consider before the project is

going to be carry out and scope of the project’s work.

1.1 PROBLEM STATEMENT

In this project, problem statement is the important aspect that use to achieve the

objective. This mobile robot is controlled by wireless communication, Wi-Fi. As an

operator, it is important to know the robot whereabouts during the mission. The problem

statement is how to program the Global Positioning System (GPS) device that provide a

location information of the robot.

1.2 OBJECTIVES

The aims of the project are set as follows:

i. To develop location finder system for a mobile robot application.

ii. To conduct comparison study on different type of GPS.

1.3 HYPOTHESIS

Location sensor can be used to address this issue. Global Positioning System

(GPS) device is used to provide a location information of the robot.

1.4 SCOPE OF THE PROJECT

The scope of this project is concentrate on the programing of Global Positioning

System (GPS) device that provide a location information of the robot. The project scope

covers the positioning accuracy is within 25 feet and the GPS receiver used is 8 channel

positioning system.

http://en.wikipedia.org/wiki/Satellite_navigationhttp://en.wikipedia.org/wiki/Satellite_navigation


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CHAPTER 2

LITERITURE REVIEW

2.0 INTRODUCTION

This chapter explains about research of the project that has been chosen and

explanations about Global Positioning System which influence in mobile robot

positioning, location identification for the robot to carry on task given to it

2.1 ROBOT

Robotics is a scientific area which researchthe connectionamong Action and

Perception. Robotics unlike to some other branches is a realistically new domain of

engineering. It's a multi-disciplinary sector. The various branches filled in the

development of Robotics are Computer Engineering, Electrical Engineering and

Mechanical Engineering. Computer Engineering, work with the mobility development

and paying attention of Robots while Electrical Engineering is works with the

handling& intelligence (sensing) of Robots. For Mechanical Engineering, itworks with

the machine &design of the Robots.

Robot is a device which capable tocarry out activities as a man. It is

programmable manipulator capable to perform numerous operations (e.g., component

handling and material), following programmed routes to satisfy a hugenumber of tasks.

Robots are classified depend on the circuits of the Robots and the some of application it

may carry out. The robots are generally classified in about three types which are Simple

level robot, Middle level Robot and Complex level Robot. Simple level robotsare

generallyprogrammed machines that usually do not consistcomplicated circuit. They are

created in order to extend man potential. For example is washing machine. Middle level

Robots are programmed however it cannot be reprogrammed. These types of robots

consist of sensor based circuit &able to do multiple tasks. For Example Fully Automatic

Washing Machine.Complex level Robotsare usually programmed and possibly be

reprogrammed too. They consist complicated model based circuit. For Example- Laptop

or Computer.


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2.1.1 Types of Robotics

Robotics can be an area of interest to peoplefor more than one century. A robot’s

distinctiveness changeswith regards to theenvironment it works in. The type of robotics

are:

2.1.1.1 Outer Space

Robotic arms which are under the control of a person who are engaged to unload

the docking cove of outer-space shuttles in order to release satellites or to develop a

space station.Robotic arms which are under the control of a person who are engaged to

unload the docking cove of outer-space shuttles in order to release satellites or to

develop a space station.Robotic arms which are under the control of a person who are

engaged to unload the docking cove of outer-space shuttles in order to release satellites

or to develop a space station.Robotic arms which are under the control of a person who

are engaged to unload the docking cove of outer-space shuttles in order to release

satellites or to develop a space station.

2.1.1.2 The Intell igent H ome

Robotic systems can currently look at home safety, ecological situation and

energy usage. Windows and doors might be unlocked mechanically and electrical

device for exampleair conditioner and lightsmight be pre-programmed to turn on. This

can helps citizens to savour home appliances no matter their own range of

motion.Robotic systems can currentlylook at home safety, ecological situation and

energy usage. Windows and doors might be unlocked mechanically and electrical

device for exampleair conditioner and lightsmight be pre-programmed to turn on. This

can helps citizens to savour home appliances no matter their own range of motion.

2.1.1.3 Exploration

Robots may get into the environments which are harmful to people. An

illustration is observing the surroundings within a volcano or looking into our deep

marine lifestyle. NASA has utilized robotic probe regarding environmental review,

from the time that earlier 60’s.


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2.1.1.4 M il i tary Robots

Flying robot drones are produced directly into performedregarding close up

view within current time’s modern armed force. Later on, robotic aircraft and motor

vehiclesmay be employed to send bombs, petroleum, bullets, and many others.Flying

robot drones are produced directly into performedregarding close up view within

current time’s modern armed force. Later on, robotic aircraft and motor vehiclesmay be

employed to send bombs, petroleum, bullets, and many others.

2.1.1.5 Farms

Programmed robots are usually used by farmer to be able to cut and collect

plants. To feed and milk the cowsdiatantly, the farmers are usually use robotic milk

farms. Programmed robots are usually used by farmer to be able to cut and collect

plants. To feed and milk the cowsdiatantly, the farmers are usually use robotic milk

farms.

2.1.1.6 The Car I ndustry

Robotic arms are used, these kinds of robot canperforma lot of tasks inside car

production& assembling procedure. They performtask for examples cutting,sorting,

lifting,welding, bending andpainting. Inorder to perform tasks such as trimming, cutting

and processing of different types of meats (chicken, meat, lamb, and fish) the farmer are

now created a similar feature of robot using a small size for food industry.

2.1.1.7 Hospital s

The growth of the robotic suit is actually under construction that will permitthe

medical stuff to boost patients without hurting their backbones. Scientists in Japan have

created a energy facilitated suit that may supply the medical staff the extra energy that

they have to lift patients.The growth of the robotic suit is actually under construction

that will permitthe medical stuff to boost patients without hurting their backbones.

Scientists in Japan have created a energy facilitated suit that may supply the medical

staff the extra energy that they have to lift patients.


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2.1.2 APPLICATIONS OF ROBOTS

Robot is a device which capable to carry out activities as a man. It’s

programmable manipulator capable to perform numerous operations (e.g., component

handling and material), following programmed routes to satisfy a hugenumber of tasks.

Robots are classified depend on the circuits of the Robots and the some of application it

may carry out. The robots are generally classified in about three types which are Simple

level robot, Middle level Robot and Complex level Robot. Simple level robotsare

generallyprogrammed machines that usually do not consistcomplicated circuit. They are

created in order to extend man potential. For example is washing machine. Middle level

Robots are programmed however it cannot be reprogrammed. These types of robotsconsist of sensor based circuit &able to do multiple tasks. For Example Fully Automatic

Washing Machine.Complex level Robotsare usually programmed and possibly be

reprogrammed too. They consist complicated model based circuit. For Example- Laptop

or Computer.

Nowadays, robots execute a variety of task in several sector and also the

quantity of jobs represented in order to robots will beincrease gradually. The easiest

method to divide robots straight into types is a partition through their application.

2.1.2.1 Industr ial r obots

This types of robots provide directly perform in an industrial manufacturing

surrounding. Usually this include jointed arms specially made for used like- material

welding ,handling, painting, and many others. These kind of robots may also contain a

few automatically guided motor vehicles and other robots if all of us analyze basically

through application.Thistypes of robots providedirectly perform in an industrial

manufacturing surrounding. Usually this include jointed arms specially made for used

like- material welding ,handling, painting, and many others. These kind of robots may

also contain a few automatically guided motor vehicles and other robots if all of us

analyze basically through application.


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2.1.2.2 Medical r obots

Robots are used in medication and medical institutes. Robot can be found during

surgical treatments. Also, several robotic focused automobiles and maybe raising

supporters.Robots are used in medication and medical institutes. Robot can be found

during surgical treatments. Also, several robotic focused automobiles and maybe raising

supporters.

2.1.2.3 Mil itary robots

Flying robot drones are produced directly into performedregarding close up

view within current time’s modern armed force. Later on, robotic aircraft and motor

vehiclesmay be employed to send bombs, petroleum, bullets, and many others. Robots

added directly into performed in armed forces & military. This kind of robots contain

explosive device removing robots, search drones , various shipping robots. Usually

robots in the beginning created for armed forces and military functions can be used in

seek andsave, enforcement law and other associated sector.


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2.2 MOBILE ROBOT

Mobile robot is surely an autonomous system that's to improve its motion in a

reaction to adjustments in its environment while performing a given task. Mobile robot

are segregated by different system into their capacity to generate developed response.

(Muhamad Ashadi B Abdul Rahman,2007) A number of systems are applied in robotic

and have interaction for making the particular robot function. There are several kinds of

mobile robot which is handled by directed wired control, wired computer control,

infrared, radio frequency (RF), Bluetooth, and Wi-Fi (Wireless Fidelity).

Mobile robot is a platform with a great mobility in thesurrounding(land,

underwater, air). It is a system with the following functional characteristics which are

mobility (total mobility relative to the environment) ,A certain level of autonomy

(limited human interaction) and Perception ability(sensing and reacting in the

environment).

2.2.1 Type of Mobile Robot

There are many possible method to move, and mobile robot design generally features a

robot will perform. Here have three the most popular mobile robot which are

i. Land-based wheeled robot

ii. Land-based legged robot

iii. Land-based tracked robot

2.2.1.1 Land Based Wheeled Robot

Figure 2.1 : Land Based Wheeled Robot

Source : Coleman Benson ,2012

http://www.robotshop.com/wheeled-development-platfoms.htmlhttp://www.robotshop.com/legged-development-platfoms.htmlhttp://www.robotshop.com/tracked-development-platfoms.htmlhttp://www.robotshop.com/tracked-development-platfoms.htmlhttp://www.robotshop.com/legged-development-platfoms.htmlhttp://www.robotshop.com/wheeled-development-platfoms.html


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Land Based Wheeled Robot is a locomotion mechanism and it has been the most

popular in mobile robot industries. With a relative mechanical implementation, a good

efficiencies can be achieve. There are four major wheel classes.Choice of wheel types

has large effect on the overall kinematics of the mobile robot because they differ widely

in their kinematics.. (Roland Siegwart and Illah R. Nourbakhsh, 2004). Mobile robot

can have just about any number of wheel, The advantage of using four and six wheeled

robot are the robot using multiple drive motor, one connected to each wheel which

reduce slip. The wheel has always been the easiest way to implement mobility. The

implementation is very simple and does not requires any advanced technique

2.2.1.3 Land Based Tracked Robot

Figure 2.2 : Land Based Tracked Robot


The figure shows the example of land based tracked mobile robot. Tracks, also

known as threads are similar to the tank. It is suitable for mobile robot in rough and

irregular surface as track provide friction and reduce slippage. Tracks is best for mobile

robot used for outdoors and off-road grounds. Land based tracked robot can easily cross

over larger obstacles due to their greater area of ground contact and can be used on

almost any terrain.

Land based tracked mobile robot is used skid steer drive as a mechanism to

moving. Skid steer is related to the differential drive system. The tracks is attached on

the two side of the mobile robot chassis and driven by two separate motor. It is steered

by moving those tracks at different speeds in the same or opposite direction.


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2.2.1.4 Land Based Legged Robot

Figure 2.3: Land Based Legged Robot


Land based legged robot is a complex mobile robot, but there are many

advantages of leg over wheel and tracked mobile robot. Legs are often the choice for

robots that must drive on uneven region. Mostly, to allow the robot to be statically

balance, the robot are designed with six legs. It will hard to balance if the robot have

fewer legs. An experiment has been carried our by researchers with monopod (one

Legged) designs, bipeds (two legs), quadrupeds (four legs) and hexapods (six legs).

(Coleman Benson .2012).


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2.3 MOBILE ROBOT AND IT’S ISSUE

Nowdays, mobile robotic very popular and always used in any sector.

Eventhough it is very popular and widely used, mobile robot still has some problems.

2.3.1 Location And Status Reporting

As an operator, it is important to know the robot whereabouts during a mission.

Losses may happen if the robot position/location is failed to be identified. Robot

tracking movement may also cannot be recorded which this usually give important

information. For SAR(Search and Rescue) operation, failed to know the location isuseless.

2.3.2 Range And Control

For a mobile robot, there is a limit distance rangeto control it. Thisproblem will

limits theabilityof amobile robottocarry outtheir mission. As an operator, they cannot

leave their mobile robot out of distance range.


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2.4 POSITIONING SENSOR

Exact knowledge of the position of a vehicle is a fundamental problem in mobile robot

applications. In search for a solution, researchers and engineers have developed avariety of systems, sensors, and techniques for mobile robot positioning. Here there are

seven categories for positioning systems which are Odometry, Inertial Navigation,

Magnetic Compasses, Active Beacons, Global Positioning Systems, Landmark

Navigation, Model Matching. The characteristics of each category are discussed and

examples of existing technologies are given for each category.(J. Borenstein, H.R.

Everett, L. Feng, and D. Wehe . 2000)

2.4.1 Odometry

Odometry is the most widely used navigation method for mobile robot

positioning; it provides good short-term accuracy, is inexpensive, and allows very high

sampling rates. However, the fundamental idea of odometry is the integration of

incremental motion information over time, which leads inevitably to the unbounded

accumulation of errors. Specifically, orientation errors will cause large lateral position

errors, which increase proportionally with the distance travelled by the robot. Despite

these limitations, most researchers agree that odometry is an important part of a robot

navigation system and that navigation tasks will be simplified if odometric accuracy can

be improved. For example (Cox, I.J., 1991), (Byrne et al. 1992), and (Chenavier, F. and

Crowley, J., 1992) propose methods for fusing odometric data with absolute position

measurements to obtain more reliable position estimation.

Odometry is based on simple equations (see Borenstein et al., 1996a), which

hold true when wheel revolutions can be translated accurately into linear displacement

relative to the floor.

However, in case of wheel slippage and some other more subtle causes, wheel

rotations may not translate proportionally into linear motion. The resulting errors can be

categorized into one of two groups: systematic errors and non-systematic errors

[Borenstein and Feng, 1996]. Systematic errors are those resulting from kinematic

imperfections of the robot, for example, unequal wheel diameters or uncertainty about


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the exact wheelbase. Non-systematic errors are those that result from the interaction of

the floor with the wheels, e.g., wheel slippage or bumps and cracks. Typically, when a

mobile robot system is installed with a hybrid odometry/landmark navigation system,

the density in which the landmarks must be placed in the environment is determined

empirically and is based on the worst-case systematic errors. Such systems are likely to

fail when one or more large non-systematic errors occur.

2.4.2 Inertial Navigation

Inertial navigation uses gyroscopes and accelerometers to measure rate of

rotation and acceleration, respectively. Measurements are integrated once (or twice, for

accelerometers) to yield position. Inertial navigation systems have the advantage that

they are self-contained, that is, they don't need external references. However, inertial

sensor data drift with time because of the need to integrate rate data to yield position;

any small constant error increases without bound after integration. Inertial sensors are

thus mostly unsuitable for accurate positioning over an extended period of time.

2.4.3

Magnetic Compasses

Vehicle heading is the most significant of the navigation parameters (x, y, and _ )

in terms of its influence on accumulated dead-reckoning errors. For this reason, sensors

which provide a measure of absolute heading are extremely important in solving the

navigation needs of autonomous platforms. The magnetic compass is such a sensor. One

disadvantage of any magnetic compass, however, is that the earth's magnetic field is

often distorted near power lines or steel structures (Byrne et al., 1992). This makes the

straightforward use of geomagnetic sensors difficult for indoor applications.

Based on a variety of physical effects related to the earth's magnetic field, different

sensor systems are available:

i. Mechanical magnetic compasses.

ii.

Fluxgate compasses.


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iii. Hall-effect compasses.

iv. Magnetoresistive compasses.

v. Magnetoelastic compasses.

The compass best suited for use with mobile robot applications is the fluxgate

compass. When maintained in a level attitude, the fluxgate compass will measure the

horizontal component of the earth's magnetic field, with the decided advantages of low

power consumption, no moving parts, intolerance to shock and vibration, rapid start-up,

and relatively low cost. If the vehicle is expected to operate over uneven terrain, the

sensor coil should be gimbal-mounted and mechanically dampened to prevent serious

errors introduced by the vertical component of the geomagnetic field.

2.4.4 Active Beacons

Active beacon navigation systems are the most common navigation aids on ships

and airplanes, as well as on commercial mobile robot systems. Active beacons can be

detected reliably and provide accurate positioning information with minimal processing.

As a result, this approach allows high sampling rates and yields high reliability, but it

does also incur high cost in installation and maintenance. Accurate mounting of beacons

is required for accurate positioning. Two different types of active beacon systems can

be distinguished: trilateration and triangulation.

2.4.5 Global Positioning Systems (GPS)

The Global Positioning System (GPS) is a revolutionary technology for outdoornavigation. GPS was developed as a Joint Services Program by the Department of

Defense. The system comprises 24 satellites (including three spares) which transmit

encoded RF signals. Using advanced trilateration methods, ground-based receivers can

compute their position by measuring the travel time of the satellites' RF signals, which

include information about the satellites' momentary location. Knowing the exact

distance from the ground receiver to three satellites theoretically allows for calculation

of receiver latitude, longitude, and altitude.


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2.4.6 Landmark Navigation

Landmarks are distinct features that a robot can recognize from its sensory input.

Landmarks can be geometric shapes (e.g., rectangles, lines, circles), and they may

include additional information (e.g., in the form of bar-codes). In general, landmarks

have a fixed and known position, relative to which a robot can localize itself.

Landmarks are carefully chosen to be easy to identify; for example, there must be

sufficient contrast relative to the background. Before a robot can use landmarks for

navigation, the characteristics of the landmarks must be known and stored in the robot's

memory. The main task in localization is then to recognize the landmarks reliably and tocalculate the robot's position.

In order to simplify the problem of landmark acquisition it is often assumed that

the current robot position and orientation are known approximately, so that the robot

only needs to look for landmarks in a limited area. For this reason good odometry

accuracy is a prerequisite for successful landmark detection.

Some approaches fall between landmark and map-based positioning. They use

sensors to sense the environment and then extract distinct structures that serve as

landmarks for navigation in the future.

Our discussion in this section addresses two types of landmarks: “artificial” and

“natural” landmarks. It is important to bear in mind that “natural” landmarks work best

in highly structured environments such as corridors, manufacturing floors, or hospitals.

Indeed, one may argue that “natural” landmarks work best when they are actually man -

made (as is the case in highly structured environments). For this reason, we shall define

the terms “natural landmarks” and “artificial landmarks” as follows: natural landmarks

are those objects or features that are already in the environment and have a function

other than robot navigation; artificial landmarks are specially designed objects or

markers that need to be placed in the environment with the sole purpose of enabling

robot navigation.


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2.4.7 Map-Based Positioning

Map- based positioning, also known as “map matching,” is a technique in which

the robot uses its sensors to create a map of its local environment. This local map is then

compared to a global map previously stored in memory. If a match is found, then the

robot can compute its actual position and orientation in the environment. The pre-stored

map can be a CAD model of the environment, or it can be constructed from prior sensor

data. Map-based positioning is advantageous because it uses the naturally occurring

structure of typical indoor environments to derive position information without

modifying the environment. Also, with some of the algorithms being developed, map-

based positioning allows a robot to learn a new environment and to improve positioning

accuracy through exploration. Disadvantages of map-based positioning are the stringent

requirements for accuracy of the sensor map, and the requirement that there be enough

stationary, easily distinguishable features that can be used for matching. Because of the

challenging requirements currently most work in map-based positioning is limited to

laboratory settings and to relatively simple environments.


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2.5 THE GLOBAL POSITIONING SYSTEM (GPS): PRINCIPLES &

CONCEPTS

GPS stands for Global Positioning System and was developed by the US

Department of Defense as a worldwide navigation and positioning facility for both

military and civilian use. It is a space-based radio-navigation system consisting of 24

satellites and ground support. GPS provides users with accurate information about their

position and velocity, as well as the time, anywhere in the world and in all weather

conditions.

Navigation in three dimensions is the primary function of GPS. Navigation

receivers are made for aircraft, ships, ground vehicles, and for hand carrying by

individuals. GPS provides specially coded satellite signals that can be processed in a

GPS receiver, enabling the receiver to compute position, velocity and time. Good GPS

receivers can calculate their position, anywhere on earth, to within one hundred meters

and can continuously update their position more than once a second. Of course, various

factors, such as terrain and atmospherics can affect the GPS signals. In spite of this

however, accuracy of one hundred meters for GPS will commonly be exceeded.(Baddar

Abbas. 2012)

2.5.1 Global Positioning System (GPS) And Field Navigation

Navigation is vital to the safety of any field expedition. When combined with

the necessity of fixing a location’s co-ordinates for scientific research, the need for

accurate, rapid and cost-effective navigation tools becomes paramount. Increasingly

GPS receivers are becoming a standard – some would say essential – item of expedition

equipment. Determining the co-ordinates of a point in the field can be achieved in a

number of ways. The most common traditional approach involves triangulation with a

map and magnetic compass. Triangulation is often very accurate but relies on accurate

maps and navigable objects. (J. Borenstein, H.R. Everett, L. Feng, and D. Wehe. 2000).


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2.5.2 Global Positioning System (GPS) Functions

GPS use satellite data to calculate an accurate position on the earth. These

calculations can relate the user’s position to almost any map projection within

milliseconds. All GPS work in a similar manner but they often look very different and

have different software. The most significant difference between GPS receivers is the

number of satellites they can simultaneously communicate with. Most receivers are

described as 12 channel meaning they can communicate with 12 satellites. Older models

may be 8 or even 5 channel with more modern receivers capable of communicating with

14 – 20. Given the current (2005) makeup of the GPS satellite’s constellation 12

channel is more than adequate.

Almost all units have an LCD screen or at least software that links to a PC/PDA

with an output screen. The unit might have several different pages that can be displayed

on screen but usually the default page is very similar. Commonly on starting a receiver

you will be presented with a map of the satellites in view. The GPS receiver shows a

view of the sky split into four quadrants. These represent the NE, SE, SW, NW parts of

the sky, with the concentric circles representing the horizon at 90° from the zenith, with

the inner circles representing 60° and 30°. The cross at the centre represents the zenith.

The dots/circles represent the satellites and the bars at the bottom represent satellite

signal strength. The higher the bar the stronger the signal. This display is typical of a 12

channel set. The dots and bars will commonly be labelled with a number to represent

the identity of the satellite. The bars are commonly either hollow or solid (usually white

or black on a monochrome display). Hollow lines represent a satellite for which the

Ephemeris data is not known. It is therefore not being used to calculate a position. Black

bars represent “Fixed” satellites whose ephemeris data has been collected successfully.

These satellites are thus available for calculating a position. This is not consistent across

all models and some may use grey bars as well as hollow bars to represent satellites not

yet fixed.

The number, position and strength of signal from the satellites allows the GPS to

calculate a rough estimate of the error in its reported position. This error or dilution of

precision is a good guide to how accurate any reading would be. It should be closely


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monitored and readings should only be taken when this is below 10m (ideally below

5m).

The way the GPS records data is generally the same across all units. GPS

receivers automatically records data into their memory according to elapsed time or

distance moved. These points are called track points. The device can be forced to record

additional data, generally with additional information, at user discretion. These user

recorded points are called waypoints. Some of the common pages used for viewing this

data are shown below. The more expensive sets have more detailed screens.

(J.Borenstein, H.R. Everett, L. Feng, and D. Wehe. 2000)

2.5.3 Global Positioning System (GPS) Working Principle

GPS signals do not contain positional data. The position reported by the receiver

on the ground is a calculated position based on range-finding triangulation. GPS

positioning is achieved by measuring using 3 stages. (Baddar Abbas. 2012)

2.5.3.1 Stage 1 The Satell i tes Act As Reference Points.

The nominal GPS Operational Constellation consists of 24 satellites at an

altitude of 20,100 km (12,500 mi) and with a period of 12 hours. The satellite orbits

repeat almost the same ground track (as the earth turns beneath them) once each day.

There are six orbital planes with nominally four satellites in each, equally spaced (60

degrees apart), and inclined at about 55 degrees with respect to the equatorial plane to

ensure coverage of Polar Regions. This constellation provides the user with between

five and eight satellites visible from any point on the earth. Powered by solar cells, the

satellites continuously orient themselves to point their solar panels toward the sun and

their antennas toward the earth. Each satellite contains four atomic clocks.

The orbital motion of each one is monitored by the Master Control facility

located at Schriever Air Force Base (formerly Falcon AFB) in Colorado. The Master

Control station computes precise orbital data (ephemeris) and clock corrections for each

satellite. It uploads ephemeris and clock data to the satellites. The satellites then send

subsets of the orbital ephemeris data to GPS receivers over radio signals. The control


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segment also ensures that the GPS satellite orbits and clocks remain within acceptable

limits. These precise positions and data form the basis for all GPS calculations.

2.5.3.2 Stage 2 : The Signal Travel Time Gives Di stance I nformation.

GPS satellites carry atomic clocks that provide extremely accurate time. The

time information is placed in the codes broadcast by the satellite so that a receiver can

continuously determine the time the signal was broadcast. The signal contains data that

a receiver uses to compute the locations of the satellites and to make other adjustments

needed for accurate positioning. The receiver uses the time difference between the time

of signal reception and the broadcast time to compute the distance, or range, from the

receiver to the satellite. The receiver must account for propagation delays, or decreases

in the signal’s speed caused by the atmosphere. To calculate the distance between itself

and any given satellite the receiver multiplies the travel time by the speed of light. This

principal is fundamental to GPS.

2.5.3.3 Stage 3 :Thr ee Distances Gives The Position.

Once stages 1 and 2 have been accomplished we now have distance information

to a number of satellites the locations of which we know with great precision. From this

data, the receiver triangulates an exact position. Three satellites are needed to determine

latitude and longitude, while a fourth satellite is necessary to determine altitude. An

atomic clock synchronized to GPS is required in order to compute ranges from these

three signals. However, by taking a measurement from a fourth satellite, the receiver

avoids the need for an atomic clock. Thus, the receiver uses four satellites to compute

latitude, longitude, altitude, and time.


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Figure 2.4 : Global Positioning System (GPS) working principle

Source : Baddar Abbas. 2012


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2.6 POSITIONING COORDINATE AND READING

For recreational navigation purposes, Latitude and Longitude and the Universal

Transverse Mercator (UTM) are the main coordinate systems to know.(Gilbert

Grosvenor,1954)

2.6.1 Latitude and Longitude, the True Coordinate System

The Earth is divided into a grid of circular segments which are perpendicular to

one another, called latitude and longitude. Latitudelines run horizontally, and are

parallel to the equator.Degrees latitude arenumbered from 0°to 90° north andsouth. Zero

degrees(0°) is the equator,90° north is theNorth Pole, and 90°south is the SouthPole.

Latitude iscommonly the first number expressed in a lat/long coordinate and is often

expressed in the form of degrees, minutes, and seconds, for instance: N38°47'30"

Longitude lines (also called meridians) run perpendicular to latitude lines. Their

spacing is widest at the equator, and converges at the Poles.The prime meridian or

Greenwich Meridian (0° longitude) runsthrough Greenwich, England. Half way around

the Earth, the degreesmeet (180° east and west) in the Pacific Ocean, just west of the

MidwayIslands, and just East of the Fiji Islands and New Zealand. Longitude

iscommonly the second number expressed in a lat/long coordinate, and is often

expressed in the form of degrees, minutes, and seconds Degrees are often divided into

minutes (') and seconds ("). Each degree has 60 minutes and each minute has 60

seconds. Seconds can be divided further in tenths, hundredths, etc. for greater and

greater precision. An example of using lat/long to describe a specific point is that the

NationalGeographic Society in Washington, DC is located at 38°54'19" N,77°02'14" W(38 degrees, 54 minutes, 19 seconds north of the equator,and 77 degrees 2 minutes, 14

seconds west of the prime meridian).


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2.6.2 Universal Transverse Mercator (UTM) Grid Coordinate System

The USGS also uses a measurement system called the UniversalTransverse

Mercator(UTM) grid coordinate system, which divides theearth into a perpendicular

grid with constant linear surface distances, inmeters, between each of its grid lines in all

directions. UTM wasdeveloped in order to reduce the complexity of the calculations

needed to transfer a location on our spherically-shaped planet to a flat surface. The

Transverse Mercator Projection, which divides the earth like theslices of an orange and

flattens the slices, introduces a negligible amountof distortion for map scales typical of

most topographic maps. The slightamount of distortion of the geographical features

within a zone isnegligible and may be ignored by most map users. The UTM Grid

Coordinate System superimposes a perpendicular grid over these earth slices with

constant linear surface distance values between each of its grid lines in all directions.

Since the pattern of UTM grid lines wassuperimposed on the grid zones after they were

flattened, these grid linesare straight, perpendicular, and they are not distorted. This grid

isdesigned to create a system where each location can be determined fromthe 0,0 point

in meters or by its grid coordinates. A reference in theUTM system can be converted

into a reference in another system, suchas latitude and longitude using computer

software.

2.6.3 UTM Measurements & Coordinates:

2.6.3.1 Eastings

Each UTM zone is 6° wide, and uses the centralmeridian as a reference. Zone

numbers designate 6degree longitudinal strips extending from 80degrees South latitude

to 84 degrees North latitude,for a total of 60 zones.

For example, Zone 10 extends from 126° West to120° West Longitude. The

central meridian is 123°,halfway (3°) from the boundary meridians. Asanother example,

Zone 14 has a central meridian of99° West Longitude.

Eastings, longitudinal measurements within eachzone, are measured from the

central meridian. Thecentral meridian has a false easting of 500,000m toassure positive


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coordinates. Thus, a location in Zone10 that falls directly on the 123° meridian would

have an easting of 500,000 meters written: 500000Em

A location 10,382 meters west of the central meridian (500,000 - 10,382=

489,618) would be written as 489618Em; likewise, a location 85,640meters east of the

central (123°) meridian would appear as 585640Em. On a GPS unit, this would be 10 Q

585640. (Note that the Q in this example is arbitrary, see Northings which describe

Zone characters).

2.6.3.2 Nor thi ngs

Northings are measured from the equator (with a 10,000,000km falsenorthing

for positions south of the equator). Zone characters designate8 degree zones extending

north and south from the equator.

Zones are divided into sections of latitude that are 8 degrees in height.These

sections are lettered C through X, with M and N bracketing theequator. The letter

designators give a quick reference as to the latitude ofa point indicted by the

coordinates. The letter designator is merely a help however. While the zone number is

critical, as the easting coordinate is referenced to it, the northing coordinate specifies the

total number of meters from the equator, regardless of lettered zone section.

Again, easting indicate the number of meters of longitude within the numbered

zone the same easting coordinate value will repeat for each zone. Eastings are specified

as six-digit numbers.

Northings, however, are specified regardless of lettered section. Northings

specify the absolute number of meters from the equator. Northings are specified as

seven-digit numbers. There are special UTM zones between 0° and 36° longitude

above 72° latitude and a special zone (32 ) between 56° and 64° north latitude.


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CHAPTER 3

METHADOLOGY

3.0 INTRODUCTION

This project thesis is focusing on programing the GPS system device which

provide a location information of the mobile robot. The Global Positioning System

(GPS) is a space-based satellite routing system that gives position and also period

details in every weather conditions, wherever on or even close to the Earth where there's

a clear distinctive line of sight to four or more GPS satellites

On this chapter, procedure of experiment is very important. For this experiment,

the equipment and materials used are computer GPS, mobile GPS and Smartphone

GPS. For the procedure of experiment, there are four stage. The first stage is GPS

setting. On this stage the GPS is setup on the computer . For the second stage which is

GPS response testing, the GPS have to find any response by using the software that

come with the GPS. On the third stage accuracy experiments is proceed. After

that, test the accuracy of GPS with other type of GPS and check the number of

active channels. The test will be carried out at three different place which are

between the building, open space and trees area. Finally, it will come to real time

monitoring stage. For this stage, the GPS will be test on the mobile robot.

http://en.wikipedia.org/wiki/Satellite_navigationhttp://en.wikipedia.org/wiki/Satellite_navigation


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3.1 EQUIPMENT AND MATERIALS

3.1.1 Global Positioning System On Computer

Figure 3.1 : Mouse GPS

Laptop computer can be turn into a Global Positioning System navigation by

installing a compact and cheap receiver, and friendly mapping software. The bad things

of this GPS is less of portability when compared to others types of GPS. The good

things about this GPS involve a quite huge screen display lots of map details, and able

to carry out detailed way planning and evaluation, when the software is great. One of

the example device that can use is GPS mouse. This device have adopt SkyTraqvenus 6

chipest with 65 channel for fast acquisition and reacquisition. This GPS mouse also

have high sensitivity (to -160dBm) and excellent performance in any weather

(cold/warm/Hot). This device also enable WAAS (Wide Area Augmentation System )

and EGNOS (Euro Geostationary Navigation Overlay Service).


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3.1.2 Mobile Global Positioning System

Figure 3.2: Mobile GPS

The whole purpose of mobile GPS is to inform you, effectively and dependably,

way to get from one place to another place. Because of this, redirecting accuracy and

reliability remains to be the most important characteristic to discuss. It required to

dependably provide directions, offer an up-to-date data of routes and points of interest

(POIs), and also show minimum lag through obtaining any signal from satellite.

When it comes to providing the directions, a little of lag causes any less-than-

optimal last minute lane swap or turn. This device also enable WAAS (Wide Area

Augmentation System )


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3.1.3 Smartphone Global Positioning System (GPS)

Figure 3.3: Smartphone GPS

To find out where the location is and to obtain turn-by-turn directions to the

location where to go.Brand-new phones that consistglobal positioning system (GPS)

receivers can perform just like that. Using thesuitable software or service package, they

are able todetermine where you are, provide way direction to where you want to go and

also provide details about nearby businesses.

A mobile phone is actually a complicated two-way radio. Base stations and

towers, are setup into a network of cells, deliver and receive radio signals. mobile

phones consist of low-power transmitters which can allowall of them get in touch with

the nearby tower.

When a person travel, they are move from one cell to another cell, and strength of the

phone’s signal is monitored by base station. When a person move toward the edge of

one cell, the strength of phone signal will decrease.While doing so, strength of the

signal will increase and this will update by base station when the person approach it.

When a person go from one cell to another cell, the towers transport the signal from one

to another. Latest smartphone has GLONASS (Global Orbiting Navigation Satellite

System) chip.

http://electronics.howstuffworks.com/gadgets/travel/gps.htmhttp://electronics.howstuffworks.com/cell-phone.htmhttp://electronics.howstuffworks.com/radio.htmhttp://electronics.howstuffworks.com/radio.htmhttp://electronics.howstuffworks.com/cell-phone.htmhttp://electronics.howstuffworks.com/gadgets/travel/gps.htm


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3.2 PROCEDURE

NO

YES

REAL TIME MONITORING

ACCURACY EXPERIMENTS

FINISH

START

GPS SETTING

GPS RESPONSE

TESTING


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For the procedure of experiment, there are four stage. The first stage is GPS setting. On

this stage the GPS is setup on the computer. For the second stage which is GPS

response testing, the GPS have to find any response by using the software that come

with the GPS. On the third stage accuracy experiments is proceed. After that, test the

accuracy of GPS with other type of GPS and check the number of active channels. The

test will be carried out at three different place which are between the building, open

space and trees area. Finally, it will come to real time monitoring stage. For this stage,

the GPS will be test on the mobile robot.

3.2.1 GPS SETTING

Setup the GPS to the computer

3.2.2 GPS RESPONS TESTING

After plug in the GPS to the computer, try to find any response by using the software

that come with the GPS.

3.2.3 ACCURACY EXPERIMENTS

Test the accuracy of GPS with other type of GPS and check the number of active

channels. The test will be carried out at three different place which are between the

building, open space and trees area.

3.2.4 REAL TIME MONITORING

Test the GPS on the mobile robot.


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CHAPTER 4

RESULTS AND DISCUSSIONS

4.0 INTRODUCTION

This chapter presents the result of Global Positioning System accuracy. The

result of GPS accuracy with 4 different types GPS under three different place. The

results obtained were then been compared in order to investigate the most accurate GPS.

4.1 GPS RESPONSE TESTING RESULT

GPS mouse on computer can detect highest GPS channel compare to

Smartphone and GPS mobile. Smartphone GPS can detect more GPS channel compare

to GPS mobile.

Table 4.1 : Number of GPS channel receiver according to type of GPS

Type of GPS Global

Positioning

System on

Computer (Mouse

GPS)

Mobile Global

Positioning

System

Smartphone

Global Positioning

System

Number of GPS

channel receiver

18 12 15

4.2 ACCURACY EXPERIMENTS

The experiment was set up on 4 different location for each type of place. After

the latitude and longitude reading was taken, it will check by using Google map to find

the distance error. From this experiment, GPS mouse on computer show the highest

accuracy followed by smartphone GPS and mobile GPS.

4.2.1 Testing Place

The experiment was carryout at 3 different place which are between the building, under the tree and open space. Each this place has 4 different location.


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4.2.1.1 Between Bui lding

(a) (b)

(c) (d)

Figure 4.1 : (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4 for between building

Table 4.2: Latitute and longitude for between building at location 1 and it distance error

GPS on computer

(Mouse GPS)

Mobile GPS Smartphone GPS

Location 1 N 3.54023

E 103.42815

Error: ±5.13m

N 3.540302

E 103.428230

Error: ±7.80m

N 3.540320

E 103.428207

Error: ±7.15m


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GPS on computer

(Mouse GPS)


Location 2 N3.53981

E103.42808

Error : ±5.35m

N3.539656

E103.428174

Error: ±7.81m

N3.539753

E103.428173

Error : ±7.14m


GPS on computer

(Mouse GPS)


Location 3 N3.54020

E103.42773

Error:±3.56m

N3.540749

E103.427804

Error: ±5.13m

N3.540743

E103.427670

Error: ±4.46m


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GPS on computer

(Mouse GPS)


Location 4 N3.53784

E103.43023

Error:±3.35m

N3.537693

E103.430315

Error: ±6.47m

N3.540743

E103.427670

Error: ±4.46m

4.2.1.2 Under the tree

(a) (b)

(c)(d)

Figure 4.2: (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4 for under the

tree


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Table 4.6: Latitute and longitude for under the tree at location 1 and it distance error

GPS on computer

(Mouse GPS)



E 103.427349

Error: ±1.29m

N 3.540402

E 103.428523

Error: ±1.93m

N 3.54042

E 103.428758

Error: ±1.87m


GPS on computer

(Mouse GPS)


Location 2 N3.538362

E103.429823

Error: ±1.34m

N3.538357

E103.429791

Error: ±1.95m

N3.53839

E103.42977

Error: ±1.85m


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GPS on computer

(Mouse GPS)



E103.429012

Error: ±2.22m

N3.539611

E103.429076

Error: ±3.42m

N3.53956

E103.42899

Error: ±2.37m


GPS on computer

(Mouse GPS)



E103.429727

Error: ±1.21m

N3.537609

E103.429717

Error: ±1.42m

N3.53761

E103.42970

Error: ±1.45m


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4.2.1.3 Open Space

(a) (b)

(c) (d)

Figure 4.3: (a) Location 1, (b) Location 2, (c) Location 3, (d) Location 4 for open space

Table 4.10: Latitute and longitude for open space at location 1 and it distance error

GPS on computer

(Mouse GPS)



E 103.428278

Error:±1.38m

N 3.53945

E 103.42831

Error:±2.72m

N 3.539496

E 103.428288

Error: ±2.95m


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GPS on computer

(Mouse GPS)



E103.428625

Error:±1.02m

N3.53832

E103.42870

Error:±1.56m

N3.538311

E103.428625

Error: ±1.12m


GPS on computer

(Mouse GPS)



E103.427395

Error:±0.53m

N3.54001

E103.42744

Error:±1.02m

N3.540013

E103.427448

Error: ±0.68m


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GPS on computer

(Mouse GPS)



E103.429257

Error:±1.42m

N3.53744

E103.42932

Error:±2.57m

N3.537393

E103.429287

Error: ±1.56m


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4.3 AVERAGE DISTANCE ERROR

Mouse GPS on computer show smallest distance error compare to Smartphone

GPS and mobile GPS. When experiment conduct between the building, average

distance error show the highest error compare to under tree and open space. By using

measuring tape, the distance error was measured from the original point stand during

experiment to the point that read from google map.

Table 4.14: Average distance error for latitude and longitude between building

GPS on Computer

(Mouse GPS)

Mobile GPS Smartphone

GPS

Error Location 1 (m) ±5.13 ±7.80 ±7.15

Error Location 2 (m) ±5.35 ±7.81 ±7.14

Error Location 3 (m) ±3.36 ±5.13 ±4.46

Error Location 4 (m) ±3.35 ±6.47 ±4.46

Average distance Error ±4.35 ±6.80 ±5.80

Table 4.15: Average distance error for latitude and longitude under the tree

GPS on Computer

(Mouse GPS)


Error Location 1 (m) ±1.29 ±1.93 ±1.87

Error Location 2 (m) ±1.34 ±1.95 ±1.85

Error Location 3 (m) ±2.22 ±3.42 ±2.37

Error Location 4 (m) ±1.21 ±1.42 ±1.45



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Table 4.16: Average distance error for latitude and longitude open space

GPS on Computer

(Mouse GPS)


Error Location 1 (m) ±1.38 ±2.72 ±2.95

Error Location 2 (m) ±1.02 ±1.56 ±1.12

Error Location 3 (m) ±0.53 ±1.02 ±0.68

Error Location 4 (m) ±1.42 ±2.57 ±1.56


4.4 DISCUSSION

GPS Mouse that connect on the computer is more accurate followed by

Smartphone GPS and Mobile GPS because GPS mouse can support Adopt SkyTraq 6

chipset with 65-channel which this help the GPS receive more satellite channel compare

to Mobile GPS and Smartphone GPS. GPS Mouse also enable WAAS (Wide Area

Augmentation System ) and EGNOS (Euro Geostationary Navigation Overlay Service).

The Wide Area Augmentation System (WAAS) will monitor and correct the ranging

signals from the GPS constellation of satellites. Most importantly, WAAS will provide

a certified level of integrity. The corrections will improve the vertical accuracy of the

system from ten or more meters to just one or two (Todd Walter, 2002). The European

Geostationary Navigation Overlay Service (EGNOS) system is being developed in

Europe to provide Global Positioning System (GPS) and GLONASS regional

augmentation services to aviation, maritime and land users. The EGNOS system, as any

other Wide Area Augmentation System (WAAS), relies on the broadcast of differential

correction and integrity information in the pseudo-range domain, which are then used to

provide a solution in the position domain (Olivier Perrin, Maurizio Scaramuzza,

Thomas Buchanan and Daniel Brocard, 2006). But currently WAAS satellite coverage

is only available in North America, Alaska, and Hawaii (Todd Walter, 2002) and

EGNOS only available in Europe and Africa (Olivier Perrin et al.,2006).


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Mobile GPS also can support WAAS but unfortunately it was not available in

Malaysia. Latest Smartphone has GLONASS (Global Orbiting Navigation Satellite

System) chip. This system works alongside GPS (Global Positioning System) to

provide position information to compatible devices. GLONASS compatible

receivers can acquire satellites up to 20% faster than devices that rely on GPS alone

(Seppanen, 2012).

Open space have smallest average distance error and reading of latitude and

longitude between the building show the highest average distance error. According

to report (Official U.S. Information Website about the GPS System Available,2012)

the horizontal positioning error is less than 17 m for 99% of the time in average

conditions or 17 m for 90% of the time in worse outdoor conditions. The error

depends on many factors, like atmospheric conditions, sun activity, geographical

location, terrain type, satellites' constellation, etc. In an open space, positioning

errors are of 2 – 3 m. However, in dense built-up areas, the location error may reach

100 m (Modsching M., Kramer R., Hagen K ,2006 and Baranski P., Strumillo P

,2011) or even more ( Ong R.B., Petovello M.G., Lachapelle G, 2009). The error is

introduced due to multipath propagation of signals transmitted by the satellites when

there is no line-of-sight. A satellite signal is bounced off the walls of a building

before finding its way to a GPS receiver. The propagation time of the signal is

delayed and the GPS receiver miscalculates its location with a reference to the

satellites.


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CHAPTER 5

CONCLUSION AND RECOMMENDATION

5.1 CONCLUSION

Global Positioning System (GPS) is a space-based satellite navigation system

that provides location and time information in all weather conditions. It is importance of

knowing and understand robot positioning, location identification for the robot to carry

on task given to it. Satellite signal is used to track and report the robot position in real

time. Therefore this system may be used as a location detection and reporting device for

this mobile robot project.

From the result shown in Chapter 4, it can be concluded that GPS Mouse

connected on the computer is more accurate followed by Smartphone GPS and Mobile

GPS. This is because, Adopt SkyTraq 6 chipset with 65-channel help the Mouse GPS

receive more satellite channel compare to Mobile GPS and Smartphone GPS. Besides

that, present of GLONASS (Global Orbiting Navigation Satellite System) chip in the

Smartphone help to acquire satellites up to 20% faster than devices that rely on GPSalone (Seppanen, 2012). Finally, increase the number of GPS channel receiver will

increase the accuracy of GPS

5.2 RECOMMENDATIONS

There are many recommendations which can be implemented in order to

improve the results and extend the scope of the experiments. The recommendationswhich can be taken into consideration are listed below:

i. The experiment can conduct between skyscrapers building.

ii. Take the reading of latitude and longitude in cloudy day for next experiment.


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