i
HARDWARE DESIGN OF THE AUTONOMOUS HELICOPTER FOR
STABILIZATION CONTROL
TEH TZE CHEE
This report is submitted in partial fulfillment of the requirements for the award of
Bachelor Of Electronic Engineering (Computer Engineering) With Honors
Faculty of Electronic and Computer Engineering
Universiti Teknikal Malaysia Melaka
UNIVERSTI TEKNIKAL MALAYSIA MELAKA
FAKULTI KEJURUTERAAN ELEKTRONIK DAN KEJURUTERAAN KOMPUTER
BORANG PENGESAHAN STATUS LAPORAN
PROJEK SARJANA MUDA II
Tajuk Projek : HARDWARE DESIGN OF THE AUTONOMOUS HELICOPTER
FOR STABILIZATION CONTROL
Sesi Pengajian : 2009/2010
Saya TEH TZE CHEE
mengaku membenarkan Laporan Projek Sarjana Muda ini disimpan di Perpustakaan dengan
syarat-syarat kegunaan seperti berikut:
1. Laporan adalah hakmilik Universiti Teknikal Malaysia Melaka.
2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja.
3. Perpustakaan dibenarkan membuat salinan laporan ini sebagai bahan pertukaran antara
institusi
pengajian tinggi.
4. Sila tandakan ( √ ) :
SULIT* (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972)
TERHAD* (Mengandungi maklumat terhad yang telah ditentukan oleh
organisasi/badan di mana penyelidikan dijalankan)
TIDAK TERHAD
Disahkan oleh:
__________________________ ___________________________________
(TANDATANGAN PENULIS) (COP DAN TANDATANGAN PENYELIA)
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“I hereby declare that this report is the resultof my own work except for quotes as
cited in the references.”
Signature :………
Author : TEH TZE CHEE
iv
“I hereby declare that I have read this report and in my opinion this report is
sufficient in terms of the scope and quality for the award Of Bachelor of Electronic
Engineering (Computer Engineering) With Honors.”
Signature :………
Supervisor’s Name : WONG YAN CHIEW
v
Dedicated to my family, specially to my beloved mother, father and sisters, my
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ACKNOWLEDGEMENTS
First and foremost, I would like to thank to my supervisor of this project,
Madam Wong Yan Chiew for the valuable guidance and advice. Her willingness to
motivate us continuously has contributed tremendously to the project. Besides, I
would like to thanks for her continuous idea in improving the project from time to
time. I also feel glad that I able to complete the project within two semester and
submit the report on time. Basically, I already fulfill the requirement of the
BENU4583 and BENU4983.
In addition, I would like to thanks the authority of Universiti Teknikal
Malaysia Melaka (UTeM) for providing with a good environment and facilities to
complete the project. It enables me to develop, etch and fabricate out the PCB board
of the helicopter control board. Besides, the authority also provides some electronic
components which lower the entire cost of this project.
Lastly, I will like to show my appreciation to my friends, my family for
providing me mental support. I will like to express my special appreciation to my
group member, Tan Teck Seong for helping me providing some useful ideas in
completing the project. Without helps of the particular that mentioned above, the
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ABSTRACT
This thesis presents the practical design approach on the stabilization of
autonomous helicopter. The common problem of the helicopter is unstable. The
helicopter will keep on rotating along the Y axis from clockwise to anticlockwise and
vice versa as it lift and hover. Therefore, an approach comes out to solve its stability
problem is to introduce the integration of an accelerometer into the helicopter’s
circuit.
A control board which is powered by microcontroller PIC16F877A is used to
control the behavior of the helicopter autonomously. The control board will be
attached to the bottom of the helicopter with connection to the top rotor, bottom rotor
and tail rotor motor. The wire is keep as shorter as possible to avoid any mechanical
trap during rotation of helicopter rotor.
The PIC16F877A is programmed to test the helicopter movements in two
stages that is test the helicopter with and without the integration of accelerometer.
For testing with integration of accelerometer, the helicopter will react accordingly to
the different accelerometer values in X and Y axis. Therefore, the particular
accelerometer values need to be set in the microcontroller programming so that the
helicopter will performs the basic movements that is hover, forward, backward, turn
left and turn right respectively. For testing without integration of accelerometer, the
helicopter also do the basic movements as mention above but without referring the
accelerometer values. The coding in the microcontroller is preset with the
movements. Each stage of movement is differentiated with the delay of 5 seconds.
The experimental results are consists of ±2% of errors from the expected results. If
viii
ABSTRAK
Kajian ini membentangkan pendekatan projek reka cipta yang praktikal
tentang Stabilisasi helikopter secara autonomi. Masalah umum helicopter adalah
tidak stabil. Helikopter itu akan terus berputar sepanjang paksi Y dari arah ikut jam
ke arah melawan jam dan sebaliknya semasa mengapungkan dirinya. Oleh sebab itu,
satu pendekatan dikaji untuk menyelesaikan masalah kestabilan dengan
mengintegrasikan accelerometer ke rangkaian helikopter.
Satu papan kawalan dipasang dengan micropengawal PIC16F877A
digunakan untuk mengawal perilaku helikopter secara autonomi. Papan kawalan itu
akan dilekatkan pada bahagian bawah helikopter dengan sambungan dawai ke motor
rotor atas, rotor bawah dan rotor ekor. Dawai mesti dikemaskan sependek yang
mungkin untuk mengelakkan dawai diperangkap semasa pusingan rotor helikopter.
PIC16F877A diprogramkan untuk menguji pergerakan-pergerakan helikopter
dalam dua peringkat iaitu menguji helikopter dengan dan tanpa integrasi
accelerometer. Untuk pemeriksaan dengan integrasi accelerometer, helikopter akan
bertindak balas mengikuti nilai-nilai accelerometer yang berbeza dalam paksi X dan
paksi Y. Antarannya, nilai-nilai accelerometer tertentu akan dimasukkan dalam
pengaturcaraan mikropengawal supaya kehendak helikopter menjalankan
pergerakan-pergerakan asas yang terapung, ke hadapan, ke belakang, belok ke kiri
dan belok kanan dengan masing-masing. Untuk pemeriksaan tanpa integrasi
accelerometer, helikopter turut melakukan pergerakan-pergerakan asas seperti
disebut di atas dengan tanpa merujuk nilai-nilai accelerometer. Keputusan
eksperimen mempunyai ± 2% kesalahan ralat daripada keputusan yang dikirakan.
Jika peratusan ralat adalah dalam julat kesalahan ralat, maka boleh dikatakan objektif
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TABLE OF CONTENT
CHAPTER TITLE PAGE
DECLARATION iii
DEDICATION v
ACKNOWLEDGEMENTS vi
ABSTRACT vii
TABLE OF CONTENTS ix
LIST OF TABLE xiii
LIST OF FIGURES xv
LIST OF ABBREVIATIONS xvii
LIST OF APPENDICES xviii
I INTRODUCTION 1
1.0 Introduction 1
1.1 Problem Statement 2
1.2 Objectives 3
1.3 Scope of Work 3
1.4 Brief Explanation of Methodology 4
1.5 Importance of Project 4
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II LITERATURE REVIEW 6
2.0 Project Background 6
2.1 Hardware Components 6
2.1.1 PIC16F877A 7
2.1.1.1 Basic pin connections 8
2.1.2 Voltage Regulator 9
2.1.3 Motor Driver 10
2.1.3.1 Pulse-Width-Modulation (PWM) 12
2.1.4 Accelerometer 14
2.1.5 Helicopter configurations 15
2.1.5.1 Helicopter Components 17
2.1.5.2 Bernoulli’s Principle 20
2.1.5.3 Battery 21
2.2 Software 22
2.2.1 PICC Compiler 22
2.2.2 Protel 99 SE 23
2.2.3 WinPic 800 USB Downloader 24
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III PROJECT METHODOLOGY 26
3.0 Introduction 26
3.1 Flow Chart Diagram 27
3.2 Hardware Design Methodology Flow Chart 30
3.3 System Block Diagram 32
3.4 Motor Operations 34
3.5 Summary 37
IV RESULT AND DISCUSSION 38
4.0 Introduction 38
4.1 Results 38
4.1.1 Helicopter Circuit 39
4.1.2 Helicopter Testing 41
4.2 Experiments 48
4.2.1 Experiment 1: Effect of different type of
batteries on RC helicopter flying time
48
4.2.2 Experiment 2: Modeling the stability
sensor
49
4.2.3 Experiment 3: Case study on helicopter
movement
51
4.3 Discussion 56
4.3.1 Selection of Motor Driver 56
4.3.2 Microcontroller connection 57
4.3.3 DC Power Source 58
4.3.4 Circuit Consideration 59
xii V VALIDATION OF AUTONOMOUS HELICOPTER 61
5.0 Introduction 61
5.1 Data Validation 61
5.1.1 Relationship between PWM values and the
helicopter movement
62
5.1.2 Relationship between accelerometer, PWM
values and helicopter movement
66
VI CONCLUSION AND RECOMMENDATIONS 72
6.0 Introduction 72
6.1 Future Work 72
6.2 Conclusions 73
REFERENCES 74
APPENDIX A 76
APPENDIX B 77
APPENDIX C 78
APPENDIX D 79
APPENDIX E 81
APPENDIX F 84
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LIST OF TABLE
NO. TITLE PAGE
2.1 Motor driver behavior in controlling the motor direction 11
2.2 RC helicopter components list 19
4.1 Components used in constructing the control board of
helicopter 39
4.2 Effect of difference PWM signal preset in the
microcontroller 43
4.3 Relation between PWM and voltage 44
4.4 Results from accelerometer during modeling the
helicopter 46
4.5 Reaction of helicopter due to unstable condition 47
4.6 Output voltage of X, Y and Z axis 50
4.7 Rotor direction testing result 54
4.8 Rotor speed testing result 55
5.1 30 data of 2 motor when PWM is 100% for both motor 62
5.2 30 data when helicopter is turn left with fix PWM values 63
5.3 30 data when helicopter is turn right with fix PWM
values 64
5.4
Error Percentages of Helicopter in its Movement
Corresponded to PWM Values 65
5.5 30 data when helicopter forward as accelerometer values
equals to 1.44 V<X<1.80 V 66
5.6 30 data when helicopter forward as accelerometer values
equals to 1.21 V<X<1.36 V 67
xiv values equals to 1.21 V<Y<1.36 V
5.8 30 data when helicopter turn right as accelerometer
values equals to 1.44 V<Y<1.80 V 70
5.9 Error Percentage of Helicopter in its Movement
xv
LIST OF FIGURE
NO. TITLE PAGE
1.1 Single rotor helicopter with 2 blades 2
2.1 PIC16F877A 7
2.2 40-pin PIC16F877A pin diagram 8
2.3 Basic connection of PIC16F877A 8
2.4 Picture of +5V and +3.3 V voltage regulators 10
2.5 Voltage regulator connection for +5V and +3.3 V output
voltages 10
2.6 Pin out diagram of L293B motor driver 10
2.7 Connection of microcontroller to motor driver 12
2.8 PWM of varying duty cycles 13
2.9 Front side view picture of 3-axis accelerometers, ADXL330 14
2.10 Conventional helicopters with single rotor configuration 15
2.11 Helicopter with double rotor configuration 16
2.12 RC helicopter with power connected 17
2.13 System architecture of RC helicopter 18
2.14 Airfoil 20
2.15 NiMH rechargeable battery at 9.6V and 450mAh 21
2.16 LiPo rechargeable battery at 11.1V & 2100mAh 21
2.17 PIC C compiler interface 22
2.18 Interface of Protel 99 SE 23
2.19 Universal USB PIC Programmer (BIZ013) 24
xvi 3.1 Flow chart of project methodology 27
3.2 Flow chart of hardware design methodology 30
3.3 Helicopter circuit system block diagram 32
3.4 Motor controlled structure 34
3.5 Flow chart of motor operation methodology 36
4.1 Components used in constructing a PCB board 40
4.2 Control board is assembled below the helicopter body 41
4.3 Position of accelerometer in a helicopter 45
4.4 Modeling result of the helicopter 46
4.5 Side view of upper rotor, lower rotor and tail rotor blade
position in a helicopter 51
4.6 Rotor positions when helicopter lift up 52
4.7 Rotor positions when helicopter turn left 52
4.8 Rotor positions when helicopter turn right 53
4.9 Rotor positions when helicopter move forward 53
4.10 Rotor positions when helicopter move backward 54
4.11 Connection of motor driver to microcontroller and motor 57
4.12 Basic connection of microcontroller 58
4.13 DC adapter with +12V 59
xvii
LIST OF ABBREVIATIONS
CPU - Central Processing Unit
DC - Direct Current
ERC
USB
mAH
GND
-Electronic Design Rule
Universal Serial Bus
milliampere-hour
Ground
LED - Light Emitting Diode
LiPo - Lithium Polymer
MCLR - Mode to clear
NiCd - Nickel Cadmium
NiMH - Nickel Metal Hydride
PIC
DIP
-Programmable Interface Controller
Dual in-line Package
PWM - Pulse-Width-Modulation
xviii
LIST OF APPENDICES
NO TITLE PAGES
A Autonomous Helicopter Schematic 74
B PCB Layout 75
C Hardware for Autonomous Helicopter 76
D C Programming for non real time testing 77
E C Programming for real time testing 80
F Journal Submitted To Submitted To Journal Of
Telecommunication, Electronic And Computer
Engineering
84
G Hardware Design of The Autonomous Helicopter for
Stabilization Control
1
CHAPTER I
INTRODUCTION
Chapter one states the objectives of hardware design of the autonomous
helicopter for stabilization control. A roughly background in this research field will
be introduced. Next, scopes of thesis listed in this chapter will layout the related
topic. Problem statement will clarify problem faced in this field. Lastly, organization
of thesis describes the structure of all five chapters.
1.0 Introduction
Helicopter is classified as rotorcraft to differentiate them from fixed-wing
aircraft such as airplane because the helicopter uses one or more horizontal rotors to
lift up. The rotor which rotates around a mast consists of two or more rotor blades.
The main advantage of a helicopter is it can easily take off and land without a
runway with the rotor which provides lift without the needing to move forward.
Therefore, it often used in congested or isolated areas as fixed-wing aircraft cannot
take off or land. Besides, the lift from the rotor allows it to hover in one area more
efficiently than other types of vertical takeoff and landing aircraft besides accomplish
tasks that fixed-wing aircraft cannot perform [1]. RC helicopter can be regarded as a
model to an actual helicopter as they have similarities in system architecture.
However, RC helicopter is not stable when it lifts up as the original design is
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the current hardware design to ensure the helicopter is balance and stable. A stable
RC helicopter is relatively important in some applications such as collecting data on
the terrain conditions. Without a stabilizing system applied in the helicopter, the data
collecting and transferring process will be simply impeded by some environment
factors such as wind. Therefore, some action need to be taken to obtain some finding
based on monitoring and controlling the stability of RC helicopter.
1.1 Problem Statement
Conventional Radio-Controlled (RC) helicopter is usually designed with a
main rotor with two blades attached to it as shown in Figure 1.1. Such RC helicopter
is hard to control due to its design is a simplified design of the original helicopter.
The design is not as sophisticated and robust as original helicopter design. Besides, it
is hard to control and unstable when it move forward or backward, turn left or right
and even make a hovering in an area. Therefore, it needs a wider space for it to hover
on an area. Furthermore, it is also easily distorted by environmental factors such as
wind due to the unstable and asymmetry weight design. The helicopter will not able
to hover in one place when the wind is strong. Therefore, an autonomous helicopter
[image:20.595.170.520.487.685.2]with stabilization system is the best alternative to solve it.
3
1.2 Objectives
The main purpose of this project is to design the hardware of the autonomous
helicopter for stabilization control. Therefore, the objectives as below should be
achieved.
i. To study the hardware design of the conventional helicopter by identifying
the helicopter’s parts functionality in contributing a helicopter system
ii. To design the helicopter to react autonomously by implementing the
functional program in C programming language into the microcontroller,
PIC16F877A which as the core of the autonomous system.
iii. To improve the control and stability of the helicopter by redesign the
hardware parts in symmetric weight condition with integrated stability sensor
iv. To analyze the stability sensor data by the microcontroller and provide the
proper feedback to the rotor movement
1.3 Scope of Work
The scopes of works in this project are:
i. Design the helicopter based on coaxial helicopter model which is a double
rotor with each rotor attached to 2 blades
ii. PIC16F877A as the microcontroller is programmed in C language
environment to control the behavior of helicopter
iii. The stability sensors, accelerometer plays an important role in providing the
helicopter’s stability condition to the microcontroller for further and thus
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1.4 Brief Explanation of Methodology
First of all, this project is started by discussing about the helicopter concepts
and ideas and its importance of the project with supervisor. Then, a lot of research is
carried on by referring various sources such as reference book, journals, datasheet for
the literature review stage. Follow on is the suitable helicopter components will be
identified and selected for this project. On next stage, the Proteus software will be
used to create and simulate the virtual circuit of the main core of the helicopter. After
that, the hardware of the helicopter will be assembled according to the design set
previously. The, the helicopter system will be test to evaluate it’s functionally to
identify if the system fulfill the project’s requirements and specifications. If the
project meet the requirements, then it is a success project and if fail to meet the
requirements, an immediate troubleshooting action will be carried on to identify the
problems and solve it.
1.5 Importance of Project
At the end of the project, the helicopter with coaxial design will be more
stable and capable than the conventional helicopter designs. It will far more stable
when it encounters some unexpected external disturbance such as environmental
factor that is wind.
Besides, the helicopter can react autonomous with relate to the current
stability state of the helicopter through real-time feedback from accelerometer which
is also known as a stability sensor. The microcontroller, PIC16F877A which is
programmed in C language environment is plays an important role in analyzing the
data gets from the stability sensors and recalculate the output voltage for the rotor
movement to enable the helicopter reach the stability state.
Furthermore, the helicopter also able to hover in an area constantly compared
to the conventional helicopter. Therefore, it only needs a narrow space for it to hover
5
robust rechargeable battery source is used. It is a great improvement compared to the
previous design and this project solely for educational purpose.
1.6 Report Structure
Chapter one will bring out introduction of hardware design of the
autonomous helicopter for stabilization control. First part of thesis will bring out
clear cut of objective, scope, problem statement of the thesis. Basic introduction and
historical background will layout on first pages of chapter one.
Next chapter will explain detail in literature review. Works done by preview
researchers in this area will bring out and discussed here. Overviews of helicopter
components and the hardware needed will be presented in this chapter.
Chapter three is related with the flow chart diagram of the project
methodology. Besides, it also includes the hardware design methodology flow chart
and system block diagram.
Chapter four consists of the result including result get through experiments.
There are total three experimentscarried on to test the components’ performanceand
functionality.
Chapter five is related to validation of data. The value of result from chapter
four will be taken for 30 times to validate the results.
Finally, in chapter six is conclude the works. Future recommendations also
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CHAPTER II
LITERATURE REVIEW
This chapter consists of literature review on theoretical concepts applied in
this project. The chapter introduces helicopter project background, helicopter rotors
concepts, stability sensor, microcontroller PIC16F877A and power source.
2.0 Project Background
A helicopter is defined as an aircraft where the lift is generated by rotating
blades. Autonomous Helicopter means that the helicopter able to fly on its own no
man control its decision making in movement and actions and is purely based on the
programming set in its Central Processing Unit (CPU). It can perform the basic
movement of helicopter that is forward, backward, turn left and turn right
autonomously based on pre-programmed microcontroller command.
2.1 Hardware Components
This section will list out and explain all the hardware components used in
helicopter. There are a lot of components involved in constructing the circuit that are
