Prototyping A Miniature Airborne Robot.
NOORANITH SHAZNI BINTI KHAIRUL AZUAR
B051010178
UNIVERSITI TEKNIKAL MALAYSIA MELAKA 2013
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PROTOTYPING A MINIATURE AIRBORNE ROBOT
This report submitted in accordance with the requirement of the
UniversitiTeknikalMalaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering (Robotics and Automation) with Honours.
by
NOORANITH SHAZNI BINTI KHAIRUL AZUAR B051010178
880324085206
FACULTY OF MANUFACTURING ENGINEERING 2013
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DECLARATION
I hereby, declared this report entitled “Prototyping a Miniature Airborne Robot” is the results of my own research except as cited in references.
Signature : ……… Author’s Name : ……….. Date : ……….
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APPROVAL
This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a partial fulfillment of the requirements for the degree of Bachelor of Manufacturing Engineering (Robotics and Automation) (Hons.). The member of the supervisory committee is as follow:
……… (Official Stamp of Supervisor)
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ABSTRACT
Unmanned aerial vehicles (UAVs) could be used for military surveillance or spying. Generally it is small and lightweight. A challenge of implementing a UAV is using the control circuit. Overall, the robot is controlled using an electronic circuit via the supplied power supply. Power supply used for this robot is 6 volts. An electronic circuit was designed to control the motor speed robot while it is flying. A type of motors used in this project is the RC motor. The robot is divided into two parts, the robot body and robotcircuit. Structural analysis is required to obtain a stable design. This project is the concept of diversifying the flight control robot using only the electronic circuit control. It also created without using any instruction or assistance of computer software programming. In the process of developing this project there are six experiments were performed. Experiment experiments were recorded and used as a study to produce this robot. The overall design constraints must be considered such as material selection, design and electronic control structure and mode of operation of the robot. At the conclusion of this study, the robot is able to fly and flying robot controlled by a circuit that has been designed.
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ABSTRAK
Kenderaan pesawat tanpa pemandu (UAV) boleh digunakan untuk pengawasan biasa atau tentera mengintip. secara umumnya ia adalah kecil dan ringan. Cabaran melaksanakan sebuah UAV adalah pengawalan menggunakan litar. Secara keseluruhannya, robot ini dikawal menggunakan litar elektronik melalui bekalan kuasa yang telah dibekalkan. bekalan kuasa yang digunakan pada robot ini adalah 6 volt. Satu litar elektronik telah direka untuk mengawal kelajuan motor robot semasa ia terbang. Jenis motor yang digunakan didalam projek ini adalah RC motor. Robot ini terbahagi kepada dua bahagian iaitu badan robot dan litar robot. Analisis diperlukan untuk memperoleh reka bentuk yang stabil. Projek ini adalah konsep mempelbagaikan robot kawalan penerbangan hanya menggunakan litar kawalan elektronik. Ia juga dibina tanpa menggunakan apa-apa arahan atau bantuan pengaturcaraan perisian komputer. Dalam proses membangunkan projek ini terdapat enam eksperimen telah dilakukan. Eksperimen-eksperimen ini telah dicatatkan dan dijadikan sebagai kajian untuk menghasilkan robot ini. Segala kekangan reka bentuk keseluruhan harus dipertimbangkan seperti pemilihan bahan, reka bentuk struktur dan kawalan elektronik serta cara operasi robot. Pada kesimpulan kajian ini, robot mampu terbang dan penerbangan robot dikawal menggunakan litar yang telah direka.
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DEDICATION
To my beloved father and mother
Khairul Azuar Bin Mat Latif and Noreha Binti Yusoff In appreciation of supported and understanding.
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ACKNOWLEDGEMENT
Firstly, I present my gratitude to Allah The Almighty for his blessings on me which allowed me to complete this project report.
I am grateful and would like to express my earnest gratitude and appreciation to my supervisor Dr. Ahmad Yushairi Bin Bani Hashim for his patience, germinal ideas and priceless guidance to finish this project. I am truly thankful for his progressive vision, his tolerance of my naive mistakes, and his dedication to my future career. Not forgetting all staff technician Universiti Teknikal Malaysia Melaka.
Not least, my sincere appreciation to my parents who have helped to support and prayer during the learning period to produce this project. To friends who have provides help, thank you also say. Spirit of friendship and your advice I will always cherish all the time. Without you all my industrial training is not going to be an achievement. Thank You.
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TABLE OF CONTENT
Abstract i
Abstrak ii
Dedication iii
Acknowledgement iv
Table of Content v
List of Table xi
List of Figure xii
List Abbreviations, Symbols and Nomenclatures xiv
CHAPTER 1: INTRODUCTION
1.1 Introduction of the Project 1
1.2 Problem Statement 2
1.3 Objective of Project 2
1.4 Scope of Project 3
CHAPTER 2: LITERATURE REVIEW
2.1 Overview of Project 4 2.2 Categories of Flying Robot 4
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2.1.1 Rotor Flying Robot 4 2.1.2 Flapping Wings Robot 4 2.1.3 Flying in a Structured Environment 5 2.3 Modelling and Design Approach Flying Robot 8 2.4 Aircraft Handling Control 9 2.5 Software
2.5.1 Proteus Software 9
CHAPTER 3: METHODOLOGY
3.1 Overview 11
3.2 Identification of the Most Tolerable Rotary Blade Combination,
Lightweight Materials and Control Tactics. 12 3.2.1 Experiment 1: Types of Rotary Blades Combinations,
Lightweight Material and Control Tactic 12
3.2.1.1 Objective 12
3.2.1.2 Theory 12
3.2.1.3 Observation 12
3.2.1.4 Results 13
3.2.1.5 Discussion 14 3.2.1.6Conclusion 14
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3.2.2 Experiment 2: Plan the path planning and the motion
of the robot 14
3.2.2.1Objective 14
3.2.2.2Discussion 14 3.2.2.3Conclusion 14 3.3 Design of the Robot Chassis, Electronics Controls 15 3.3.1 Experiment 3: Modeling and Design a Robot Chassis 15
3.3.1.1Objective 15
3.3.1.2Equipment 15
3.3.1.3Observation 16
3.3.1.4Result 16
3.3.1.5Discussion 16 3.3.2 Experiment 4: Design Electronics Controls 16
3.3.2.1Objective 16
3.3.2.2Equipment 17
3.3.2.3Theory 17
3.3.2.4Procedure 17
3.3.2.5Observation 18 3.3.2.6Precaution 18
3.3.2.7Result 18
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3.3.2.9Conclusion 18 3.4 Development of the Assembly and Testing Procedures 19 3.4.1 Experiment 5: Assembly and Testing Procedures 19
3.4.1.1Objective 19
3.4.1.2Equipment 19
3.4.1.3Theory of Experiment 19
3.4.1.4Procedure 19
3.4.1.5Experimental Set-up 21 3.4.1.6Observation 21 3.4.1.7Precautions 22
3.4.1.8Result 22
3.4.1.9Discussion 24 3.4.1.10Conclusion 24 3.5 Assessment of the Robot’s Efficiency on Airborne 24
3.5.1 Experiment 5: Tests the Efficiency of Robot 24
3.5.1.1Objective 24
3.5.1.2Equipment 25
3.5.1.3Theory 25
3.5.1.4Procedure 25
3.5.1.5Experimental Set-up 27 3.5.1.6Observation 28
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3.5.1.7Precaution 28
3.5.1.8Result 29
3.5.1.9Discussion 29 3.5.1.10Conclusion 29
CHAPTER 4 RESULT AND DISCUSSION
4.1 Overview 29
4.2 Identification of the Most Tolerable Rotary Blades
Combinations, Lightweight Materials and Control Tactics 31 4.2.1 Result of Experiment 1 31 4.2.2 Discussion of Experiment 1 33 4.2.3 Discussion of Experiment 2 34 4.3 Design of the Robot Chassis, Electronics Control 35 4.3.1 Result of Experiment 3 36 4.3.2 Discussion of Experiment 3 38 4.3.3 Result of Experiment 4 39 4.3.4 Discussion of Experiment 4 41 4.4 Development of the Assembly and Testing Procedures 41 4.4.1 Result Experiment 4 42 4.4.2 Discussion of Experiment 4 44
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4.5 Assessment of the Robot Efficiency on Airborne 44 4.5.1 Result of Experiment 5 45 4.5.2 Discussion of Experiment 5 45
CHAPTER 5 CONCLUSION AND RECOMMENDATION 47
REFERENCES 49
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xi
LIST OF TABLE
3.1 The flying robot specification 14 3.2 The voltage current value entry for motor 1 23 3.3 The voltage current value entry for motor 2 24 3.4 The voltage current value entry for motor 3 24 3.5 The voltage current value entry for motor 4 24 3.6 The output voltage the fourth motor after switch is on 24
4.1 The result of the specification of the flying robot 31 4.2 Result of the voltage current value entry for motor 1 43 4.3 Result of the voltage current value entry for motor 2 43 4.4 Result of the voltage current value entry for motor 3 44 4.5 Result of the voltage current value entry for motor 4 44 4.6 Result of the output voltage the motor only when the switch is on 44
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LIST OF FIGURES
2.1 Quadrotor concept (Fang, Wang, & Sun, 2010) 8 2.2 Flight mode of quadrotor (Fang, Wang, & Sun, 2010) 9
3.1 The flow of the project realization 12 3.2 Schematic of Proteus Software 17 3.3 The flow chart for the electronic control design procedure 18 3.4 The flow chart of the assembly and testing procedure 21 3.5 Battery supplier 6 volt 22 3.6 Position of the robot and remote controller 22 3.7 The flow chart for robot efficiency test procedure 27 3.8 The flying robots are standing on cardboard 28 3.9 Pencils are among cardboard position and robot 28
4.1 The concept of rotation flying robot 32 4.2 Schematic direction of the rotary blades 33
4.3 Rotary blades 33
4.4 Servo motor 35
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4.6 A robot sketch 37
4.7 Top view of robot chassis 37 4.8 Side view of robot chassis 38 4.9 Top view remote controller 38 4.10 Side view remote controller 38 4.11 Circuit for a motor 40 4.12 Component circuit 40 4.13 The movement of the robot during experiment assessment 46 4.14 The result from the experiment assessment 46 4.15 The prototyping a miniature airborne robot project 46
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LIST OF ABBREVIATIONS, SYMBOLS AND
NOMENCLATURE
UAV Unmanned Aerial Vehicle CPU Central Processing Unit ROM Read-only Memory RAM Random-access Memory FMA Flying Machine Arena GPS Global Positioning System BLDC Brushless DC Motor
MEMS Microelectromechanical Systems RUAV Rotor Unmanned Aerial Vehicle PCB Printed Circuit Robot
PIC Peripheral Interface Controller ISIS Intelligent Input System Schematic
ARES Advanced Routing Hardware & Software Editing VSM Virtual System Modelling
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CHAPTER 1
INTRODUCTION
1.1 Introduction of Project
The unmanned aerial vehicle (UAV) or a drone plays an essential role in military defense technology. The popularity of UAV in the past few years has surged. It is much easier to design robotic field assistants than it is constructing a tele robotic UAV as they is now becoming more intelligent and are able to execute increasingly complicated tasks. Without aircraft is a type of aircraft that do not require a pilot to operate either remotely or flown independently according to a pre-programmed flight plan. Now, most UAVs can carry out surveillance missions and dangerous attacks. The aim of this project is to developing an unmanned aerial vehicle (UAV) using electronic circuits when power are supplied. In this project, it focuses how to develop a small flying robot. This project is about ‘Prototyping a Miniature Airborne Robot’. The flying robot is controlled by a remote control. Remote controls in this flying robot are used to control the speed of the flying robot. The speed of flying robot are depends on the variable resistor. Variable resistor is used to change or adjust the speed flying robot. The controller are designed by the specification that suitable and required. In this project also are not using a programming software. It consists of two parts such as robot chassis, remote controller. The variable resistor for this controller will be connected to RC motor to adjust the speed of flying robot. After the power supply is already to supplied, a RC motor function to drive the variable resistor to rotate.
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1.2 Problem Statement
Microcontroller is a small cheap computer and built to control the electronic control. It is also designed to facilitate the tasks to be performed either manually or automatically. Normally fly in robot construction microchip because it contains all the memory and interfaces (input and output) sufficient for simple applications. It consists of basic parts that are essential to operate as a CPU, ROM, RAM, ports input or output and timer or counter. Problem statement for this project is due to be sensitive and microchip that can be easily detected by an unidentified individual as enemies and invaders.
1.3 Objective of Project
The overall design of a UAV that uses rotary blades to become airborne requires radio frequencies as control signals which chassis made of light-weight materials. The objective of this project is to build a laboratory prototype miniature robot that flies using a circuit robot controlling.
1.4 Scope of Projects
The scope of this project is the robot will be relatively small in size and in payload capability. It will have a remote control system to control a movement of robot. The flight will have a guided fixation. Besides that, the scopes of this project are:
1. Design of the robot chassis, electronics controls, 2. Development the assembly and testing procedures, and 3. Assessment the robot’s efficiency on airborne.
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CHAPTER 2
LITERATURE REVIEW
2.1 Overview of Project
Flying robots are widely used because there is a variety of functions and advantages such as in the military, defense and entertainment. In military and defense, flying robots used to make surveillance of enemy attack. Flying robots are also being used for mere entertainment. Flying robot can be divided into four types of fixed wing flying scheme, rotary wing, lighter than water and flapping wing.
2.2 Categories of Flying Robot
2.2.1 Rotor Flying Robots
The Flying Machine Arena (FMA) is state of the art experimental platform for exploration in aerial robotics and control. It depends on small quadrocopters and objective to investigate the physical and dynamical limits of both the cars and the overall control architecture. Three conferences in FMA have been brought in to generate a robot fly the airspace and motion catch volume, quadrocopter cars and control and communication (Lupashin, Schöllig, & D'Andrea, 2011).
A project lead by Gurdan, et al., (2007) developed a small, robust and extremely maneuverable independent flying robot that may be used both indoors under any
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weather conditions. The robot uses extremely high frequencies (updates rates around 50 to 100Hz) to enables extreme acrobatics maneuvers and to changing environmental conditions such as powerful, and chopping winds. According to Gurdan, the challenge to achieving this type of control is both on the hardware and the software front. There are the four rotor hardware, common design and components. The common design is contain a classical four rotor design with two center rotating pairs of propellers arranged in a square and in contact to the diagonals.
2.2.2 Flapping Wings Robot
Flapping wings cars can fill the niche left by traditional fixed and rotary wing car for little, maneuver and stealthy UAV's in military, civilian and exploration applications (Raghul, Mohammeed Ansari, & Manikandan, 2012). Ornithopter autonomy has not yet been achieved for the reason that the kinematics, aerodynamics and the stability, orientation and navigation of birds are much more difficult than that of a fixed wing aircraft. According to Raghul et al., this challenging problem has sparked a wave of exploration in ever changing modeling, flapping aerodynamics, structural routine and control technique.
They elaborate that a simple principles of the ornithopter blade element in the course of one revolution. The blade is forced to flay up and down once per revolution of the rotor, resulting in the undulating path. Unlike airplanes and helicopters, the driving airfoils of the ornithopter have a flapping or oscillating motion, in preference to rotary. A tested ornithopter should have wings skilled of generating both thrust, the force that propels the craft forward, and lift, the force, perpendicular to the direction of flight that maintains the craft airborne. These forces must be powerful enough to counter the effects of drag and the weight of the craft. A practical flapping wing must be able to flex or rotate. bendy wings can attain efficiency while keeping the driving mechanism basic, where to accomplish the desired flexibility and minimum weight must have experimented with wings that need carbon fiber, plywood, fabric and ribs with a stiff, powerful trailing.
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5 2.2.3 Flying in a Structured Environment
Developing a research autonomous plane for flying in a laboratory space is challenges that force one to understand the specific aerodynamic, power and construction constraints (Nicoud & Zufferey, 2002). They analyzed the wing, propeller and motor characteristics and propose a methodology to optimize the motor, gear propeller system. They suggested that the flying scheme can be classified into four categories such as lighter than air, flapping wings, rotary wings, and fixed wings. Airships or blimps are easiest way to make a robot fly. Powered with three or more DC motors, the vehicles are quiet and not dangerous. Provided with ingeniously arranged protections, they can bump into obstacles without damage.
Nicoud and Zufferey elaborate that a flapping wings hummingbird is the dream for many researchers. Flapping wings represent the only hope to reduce the size below 10cm wing span and quite interesting projects are currently in progress. Helicopters are most likely too dangerous and noisy. Although the R/C tends to be heavy and expensive, the lighter indoor R/C helicopter weighs only 50g and even much smaller ones are considered by scientist. But they may be too fragile, too sensitive to payload and have very limited running time.
They explained the essential elements for the modeling and design of an indoor fixed wings flying robot, with a very low flight speed and adequate maneuverability for operation in a 10mx10m room. First some principles of basic aerodynamics are summarized and the correspondence laws are applied to get some clues on what happens with small dimensions and low speed. Then the wing, propeller, and motor design are tackled. Finally, some thoughts about the weight distribution and the navigation control are given. Because of other heavy components batteries and motors the weight of the wing should be less than 5g.
In addition, they suggested that a good method for the construction of such as a wing is to employ carbon rods for the frame and a thin plastic film for the cover. Actually, the
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laminar flow is good for drag but bubbles and then vortices will form easily with the lift suction. The theoretical shape for a propeller of a given pitch is easy to understand. The pitch depends on the propeller’s rotation speed and the plane’s air speed. However, the air is pushed by the propeller at a speed that is difficult to know. For motor selection, brushless motors are the lightest and the most efficient, but they need bulky command electronics. Using coreless DC motors is almost inevitable. The problem with indoor flying is the weight of the batteries, reaching easily one third of the overall weight of plane. Considerable care must be taken to reduce the weight everywhere.
On the other hand, Fang, Wang, and Sun (2010) described about a small quadrotor flying robot for the use of indoor autonomous navigation and exploration has described. Three levels hardware architecture is developed and a fusion of different sensors is implemented, which enables automatic hovering, control from remote controller, localization and navigation in indoor environment. The use of UAV is the only effective way to reach target to get information or to deploy instrumentation. In the last ten years, UAVs have improved their autonomy dramatically with the development of GPS position technology, inertial navigation technology, communication and control technology, and image processing technology.
Today, UAVs can consider as intelligent robotic systems integrating perception, learning, real-time control, reasoning, decision making and planning capabilities for operating in complex environments. They suggested that quadrotor has some advantages such as high payload or volume ratio, good hovering ability, low noise and easy maneuverability. By using four rotors that can rotate with individually controllable speeds make unnecessary the alteration of the rotor blades incidence angle, hence the mechanical structure of the helicopter becomes quite simple. The concept of the quadrator flying robot is illustrated in figure 1. The actuator system has two pairs of counter rotating, fixed-pitch blades located at the four corners of the vehicle. Figure 2 shows the approach and the movement of the quadrotor. Quadrotor can be controlled by properly changing the revolution of the rotors.
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CHAPTER 1
INTRODUCTION
1.1 Introduction of Project
The unmanned aerial vehicle (UAV) or a drone plays an essential role in military defense technology. The popularity of UAV in the past few years has surged. It is much easier to design robotic field assistants than it is constructing a tele robotic UAV as they is now becoming more intelligent and are able to execute increasingly complicated tasks. Without aircraft is a type of aircraft that do not require a pilot to operate either remotely or flown independently according to a pre-programmed flight plan. Now, most UAVs can carry out surveillance missions and dangerous attacks. The aim of this project is to developing an unmanned aerial vehicle (UAV) using electronic circuits when power are supplied. In this project, it focuses how to develop a small flying robot. This project is
about ‘Prototyping a Miniature Airborne Robot’. The flying robot is controlled by a remote control. Remote controls in this flying robot are used to control the speed of the flying robot. The speed of flying robot are depends on the variable resistor. Variable resistor is used to change or adjust the speed flying robot. The controller are designed by the specification that suitable and required. In this project also are not using a programming software. It consists of two parts such as robot chassis, remote controller. The variable resistor for this controller will be connected to RC motor to adjust the speed of flying robot. After the power supply is already to supplied, a RC motor function to drive the variable resistor to rotate.
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2 1.2 Problem Statement
Microcontroller is a small cheap computer and built to control the electronic control. It is also designed to facilitate the tasks to be performed either manually or automatically. Normally fly in robot construction microchip because it contains all the memory and interfaces (input and output) sufficient for simple applications. It consists of basic parts that are essential to operate as a CPU, ROM, RAM, ports input or output and timer or counter. Problem statement for this project is due to be sensitive and microchip that can be easily detected by an unidentified individual as enemies and invaders.
1.3 Objective of Project
The overall design of a UAV that uses rotary blades to become airborne requires radio frequencies as control signals which chassis made of light-weight materials. The objective of this project is to build a laboratory prototype miniature robot that flies using a circuit robot controlling.
1.4 Scope of Projects
The scope of this project is the robot will be relatively small in size and in payload capability. It will have a remote control system to control a movement of robot. The flight will have a guided fixation. Besides that, the scopes of this project are:
1. Design of the robot chassis, electronics controls, 2. Development the assembly and testing procedures, and 3. Assessment the robot’s efficiency on airborne.
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3
CHAPTER 2
LITERATURE REVIEW
2.1 Overview of Project
Flying robots are widely used because there is a variety of functions and advantages such as in the military, defense and entertainment. In military and defense, flying robots used to make surveillance of enemy attack. Flying robots are also being used for mere entertainment. Flying robot can be divided into four types of fixed wing flying scheme, rotary wing, lighter than water and flapping wing.
2.2 Categories of Flying Robot
2.2.1 Rotor Flying Robots
The Flying Machine Arena (FMA) is state of the art experimental platform for exploration in aerial robotics and control. It depends on small quadrocopters and objective to investigate the physical and dynamical limits of both the cars and the overall control architecture. Three conferences in FMA have been brought in to generate a robot fly the airspace and motion catch volume, quadrocopter cars and control and communication (Lupashin, Schöllig, & D'Andrea, 2011).
A project lead by Gurdan, et al., (2007) developed a small, robust and extremely maneuverable independent flying robot that may be used both indoors under any
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4
weather conditions. The robot uses extremely high frequencies (updates rates around 50 to 100Hz) to enables extreme acrobatics maneuvers and to changing environmental conditions such as powerful, and chopping winds. According to Gurdan, the challenge to achieving this type of control is both on the hardware and the software front. There are the four rotor hardware, common design and components. The common design is contain a classical four rotor design with two center rotating pairs of propellers arranged in a square and in contact to the diagonals.
2.2.2 Flapping Wings Robot
Flapping wings cars can fill the niche left by traditional fixed and rotary wing car for little, maneuver and stealthy UAV's in military, civilian and exploration applications (Raghul, Mohammeed Ansari, & Manikandan, 2012). Ornithopter autonomy has not yet been achieved for the reason that the kinematics, aerodynamics and the stability, orientation and navigation of birds are much more difficult than that of a fixed wing aircraft. According to Raghul et al., this challenging problem has sparked a wave of exploration in ever changing modeling, flapping aerodynamics, structural routine and control technique.
They elaborate that a simple principles of the ornithopter blade element in the course of one revolution. The blade is forced to flay up and down once per revolution of the rotor, resulting in the undulating path. Unlike airplanes and helicopters, the driving airfoils of the ornithopter have a flapping or oscillating motion, in preference to rotary. A tested ornithopter should have wings skilled of generating both thrust, the force that propels the craft forward, and lift, the force, perpendicular to the direction of flight that maintains the craft airborne. These forces must be powerful enough to counter the effects of drag and the weight of the craft. A practical flapping wing must be able to flex or rotate. bendy wings can attain efficiency while keeping the driving mechanism basic, where to accomplish the desired flexibility and minimum weight must have experimented with wings that need carbon fiber, plywood, fabric and ribs with a stiff, powerful trailing.
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5 2.2.3 Flying in a Structured Environment
Developing a research autonomous plane for flying in a laboratory space is challenges that force one to understand the specific aerodynamic, power and construction constraints (Nicoud & Zufferey, 2002). They analyzed the wing, propeller and motor characteristics and propose a methodology to optimize the motor, gear propeller system. They suggested that the flying scheme can be classified into four categories such as lighter than air, flapping wings, rotary wings, and fixed wings. Airships or blimps are easiest way to make a robot fly. Powered with three or more DC motors, the vehicles are quiet and not dangerous. Provided with ingeniously arranged protections, they can bump into obstacles without damage.
Nicoud and Zufferey elaborate that a flapping wings hummingbird is the dream for many researchers. Flapping wings represent the only hope to reduce the size below 10cm wing span and quite interesting projects are currently in progress. Helicopters are most likely too dangerous and noisy. Although the R/C tends to be heavy and expensive, the lighter indoor R/C helicopter weighs only 50g and even much smaller ones are considered by scientist. But they may be too fragile, too sensitive to payload and have very limited running time.
They explained the essential elements for the modeling and design of an indoor fixed wings flying robot, with a very low flight speed and adequate maneuverability for operation in a 10mx10m room. First some principles of basic aerodynamics are summarized and the correspondence laws are applied to get some clues on what happens with small dimensions and low speed. Then the wing, propeller, and motor design are tackled. Finally, some thoughts about the weight distribution and the navigation control are given. Because of other heavy components batteries and motors the weight of the wing should be less than 5g.
In addition, they suggested that a good method for the construction of such as a wing is to employ carbon rods for the frame and a thin plastic film for the cover. Actually, the
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laminar flow is good for drag but bubbles and then vortices will form easily with the lift suction. The theoretical shape for a propeller of a given pitch is easy to understand. The
pitch depends on the propeller’s rotation speed and the plane’s air speed. However, the air is pushed by the propeller at a speed that is difficult to know. For motor selection, brushless motors are the lightest and the most efficient, but they need bulky command electronics. Using coreless DC motors is almost inevitable. The problem with indoor flying is the weight of the batteries, reaching easily one third of the overall weight of plane. Considerable care must be taken to reduce the weight everywhere.
On the other hand, Fang, Wang, and Sun (2010) described about a small quadrotor flying robot for the use of indoor autonomous navigation and exploration has described. Three levels hardware architecture is developed and a fusion of different sensors is implemented, which enables automatic hovering, control from remote controller, localization and navigation in indoor environment. The use of UAV is the only effective way to reach target to get information or to deploy instrumentation. In the last ten years, UAVs have improved their autonomy dramatically with the development of GPS position technology, inertial navigation technology, communication and control technology, and image processing technology.
Today, UAVs can consider as intelligent robotic systems integrating perception, learning, real-time control, reasoning, decision making and planning capabilities for operating in complex environments. They suggested that quadrotor has some advantages such as high payload or volume ratio, good hovering ability, low noise and easy maneuverability. By using four rotors that can rotate with individually controllable speeds make unnecessary the alteration of the rotor blades incidence angle, hence the mechanical structure of the helicopter becomes quite simple. The concept of the quadrator flying robot is illustrated in figure 1. The actuator system has two pairs of counter rotating, fixed-pitch blades located at the four corners of the vehicle. Figure 2 shows the approach and the movement of the quadrotor. Quadrotor can be controlled by properly changing the revolution of the rotors.