UNMANNED AERIAL VEHICLE

A PROJECT REPORT

Submitted by

KOPPERUNDEVI.P

MONIKA.J

MOUNIKA.B.M

in partial fulfillment for the award of the degree

of

BACHELOR OF ENGINEERING IN

ELECTRONICS AND COMMUNICATION ENGINEERING

PRATHYUSHA INSTITUTE OF TECHNOLOGY AND MANAGEMENT

ARANVOYALKUPPAM

ANNA UNIVERSITY: CHENNAI 600 025

APRIL 2015

ABSTRACT

The purpose of this paper is to introduce a novel

robot in order to overcome some difficulties in providing

an Automated External Defibrillator (AED) device at the

nearest location of victim suffering from sudden cardiac

arrest in the shortest possible time before the advent of

the ambulance. We designed and developed a vehicle that

brings along an AED to help lay rescuers for saving

patients life in a sudden event of cardiac arrest .The

first aid to the victim can be carried out once an

incident alarm is transmitted to the UAV Station by

sensing mobile phone application. Such applications

transmit required information to the UAV center for

further execution. The vehicle is located in UAV stations

when several stations can be covered via single center

where human operators are located. Here we present the

conduction of the tele-control method to control the

operation of the robot. In this method, not only vehicle

follows instructions of human operator till the robot

reaches the location of victim and delivers the AED but

also provides instruction to the people in the location

for applying the AED hence the lay rescuers will dry the

victim’s chest and attach the AED pads by themselves while

instructed and monitored by the human experts in the main

center in real-time.

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TABLE OF CONTENTS

CHAPTER TITLE PAGE NO

ABSTRACT iii

LIST OF FIGURESviii

LIST OF ABBREVIATIONS x

1 INTRODUCTION 11.1 INTRODUCTION 11.2 LITERATURE REVIEW 21.3 OBJECTIVE 31.4 EXISTING SYSTEM 3

1.4.1 Disadvantages in Existing System 4

1.5 PROPOSED SYSTEM 41.5.1 Advantages 41.5.2 Scope of the Project 4

2 IMPLEMENTATION AND DESIGN 52.1 BLOCK DIAGRAM 52.2 WORKING PRINCIPLE 7

3 COMPONENT DESCRIPTION 83.1 QUAD COPTER INTRODUCTION 8

3.1.1 Quad Copter Theory 93.1.2 The Kinetic Principle ofQuad Copter 10

3.2 MICROCONTROLLER UNIT 113.2.1 Introduction 11

iv

3.2.2 Microcontroller Packaging 123.2.3 Microcontroller Pin diagram 123.2.4 Pin Function 133.2.5 Internal Architecture 153.2.6 Memory Organization 163.2.7 Schematic and Features 183.2.8 System Clock 193.2.9 Reset Circuit 20

3.3 GSM 213.3.1 Definition 213.3.2 The GSM Network 213.3.3 GSM Modem 223.3.4 Functions of GSM 233.3.5 Applications of GSM 243.3.6 Features of GSM Communication 253.3.7 MAX 232 27

3.4 GPS INTRODUCTION 293.4.1Working of GPS 303.4.2 Three Segments of GPS 313.4.3 How GPS Works 32

3.5 ZIGBEE 333.5.1 ZigBee Physical Layer 333.5.2 The ZigBee Advantages 333.5.3 The Mesh Network 343.5.4 ZigBee Applications 353.5.5 DIGI ZigBee Technology 35

v

3.6 PROPELLERS 353.6.1 Air Foil 353.6.2 Structure of Air foils 363.6.3 Principle and Working 373.6.4 Aero Dynamic Force on the Airfoil 383.6.5 Pitch of Propellers 393.6.6 Uses of Propellers 40

3.7 FRAMES AND ARMS 403.8 DC MOTORS 41

3.8.1 Fleming’s Left Hand Rule 423.8.2 Working of Brushless DC Motors 423.8.3 Left Hand Rule for Coil 433.8.4 Brushless vs. Brushed DC Motors 43

3.9 RADIO TRANSMITTER AND RECEIVER 453.9.1 Transmitter (TX) 453.9.2 Receiver 463.9.3 HKT6A Transmitter 473.9.4 Modes of Transmitter 483.9.5 HKT6A Receiver 59

3.10 BATTERY AND CHARGERS 503.11 ELECTRONIC SPEED CABLE 513.12 DEFIBRILLATOR 51

4 SOFTWARE TOOLS 534.1 KEIL MICRO VERSION 3 53

5 RESULTS AND CONCLUSION 545.1 EXPREMENTAL RESULTS 54

vi

5.2 CONCLUSION AND FUTURE WORK 55APPENDICES 56REFERENCES 57

vii

LIST OF FIGURES

FIG.NO EXPLANATION PAGE NO

2.1 BLOCK DIAGRAM OF MONITORING UNIT 52.2 BLOCK DIAGRAM OF HELIPORT UNIT 63.1 NET MOMENT AT F3=0 93.2 DIRECTION OF ROTATION OF MOTORS 103.3 THE UPWARD THRUST MOTORS 113.4 PIN DIAGRAM 133.5 SIMPLIFIED INTERNAL ARCHITECTURE 153.6 PROGRAM MEMORY ARRANGEMENT 163.7 DATA MEMORY ORGANIZATION 18

3.8BLOCK FOR SCHEMATIC INPUT AND OUTPUTS 18

3.9 CLOCK CIRCUIT OF AT89C51 193.10 POWER ON RESET CIRCUIT 203.11 MANUAL RESET CIRCUIT 203.12 GSM NETWORK ELEMENTS 213.13 APPLICATIONS OF GSM MODEM 233.14 PIN DESCRIPTION OF MAX 232 283.15 GPS PCB BOARD DIAGRAM. 303.16 THREE SEGMENTS OF GPS 323.17 ZIGBEE MODULE 343.18 STRUCTURE OF AIRFOIL 373.19 FORCES ACTING ON AN AIR FOIL 383.20 PITCH OF A PROPELLER 39

viii

3.21 DIAGRAM OF FRAME 40

3.22 WORKING OF BRUSHLESS MOTORS 42

3.23 BRUSHLESS MOTORS 453.24 HKT6ATRANSMITTER 483.25 HKT6A RECEIVER 493.26 DIAGRAM OF BATTERY 503.26 ESC 513.27 DEFIBRILLATORS 525.1 PROTOTYPE OF QUADCOPTER 545.2 GPS SCREEN SHOT 545.3 GSM SCREEN SHOT 55

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LIST OF ABBREVIATIONS

ADC - ANALOG TO DIGITAL COVERTERAED - AUTOMATED EXTERNAL DEFIBRILLATERALE - ADDRESS LATCH ENABLEALU - ARITHMATIC LOGIC UNITDAC - DIGITAL TO ANALOG CONVERTERDIP - DUAL INLINE PACKAGEEA - EXTERNAL ACCESSEDC - ELECTRONIC DATA CAPTUREESC - ELECTRONIC SPEED CABLEGND - GROUNDGPS - GLOBAL POSITIONING SYSTEMGSM - GLOBAL SYSTEM FOR MOBILE COMMUNICATIONGUUB - GLOBALLY UNIFORMLY ULTIMATELY BOUNDEDMCS - MARKET COMMUNICATION SYSTEMNASA - NATIONAL AERONAUTICS AND SPACE ADMINISTRATIONPC - PERSONAL COMPUTERPCMCIA - PERSONAL COMPUTER MEMORY CARD INTERNATIONAL

ASSOCIATIONPOS - POINT OF SALEPQFP - PLASTIC QUAD FLAT PACKAGEPSEN - PROGRAM STORE ENABLEQFP - QUAD FLAT PACKAGERAM - RANDOM ACCESS MEMORYROM - READ ONLY MEMORYRPM - ROTATION PER MINUTE

x

SCM - SUPPLY CHAIN MANAGEMENTSIM - SUBSCRIBER IDENTITY MODULESMS - SHORT MESSAGE SERVICETQFP - THIN QUAD FLAT PACKAGEUAV - UNMANNED AERIAL VEHICLE

CHAPTER 1

INTRODUCTION

1.1 INTRODUCTION

Emergency situation refers to any unforeseen event

that. This situation can be broken down into two basic

categories, natural and manmade calamities. Natural

calamity is the phenomena of nature caused by

environmental factors that can bring catastrophic

consequences. While the world population grows rapidly

within creasing their concentration in hazardous

environments without giving much consideration to the

local geo-climatic conditions have exacerbated the

devastation caused by natural calamities. Therefore,

different forms of natural calamities like drought,

tsunami, earthquake, extreme temperature, mass movement

tweet, typhoon, and volcano strike according to the

vulnerability of threat in the globe. On the other

hand, the catastrophe can also because the consequence

of technological or human hazards, including industrial

accident and transport accident, where it is commonly

known as manmade calamity.

The ambulance has to transport the patient to the

hospital as quickly and safely as possible. However, in

many cases like life-threatening emergencies the

patient needs immediate first aid and medical attention

prevent serious danger. Meanwhile, the fate of patients

cannot be influenced by waiting the ambulance but

rather could be change different some treatments could

be given within a few minutes of the patient’s

collapse. For instance, individuals suffering sudden

cardiac arrest could be save different the Automated

External Defibrillator device known as AED is applied

within a few minutes after the occurrence of cardiac

arrest. At the same time, someone who helps the patient

must be able to perform CPR (Cardio pulmonary

Resuscitation) and attach the AED to a person in

cardiac arrest. The AED is small electronic portable

defibrillator that is designed for minimally trained or

trained non-medical personnel.

1

1.2 LITERATURE REVIEW

Scott A. Greened et al have proposed the human robot

collaboration and real time Augmented Reality Approach

in Design

NASA’s vision for space exploration stresses the

cultivation of human-robotic systems. Similar systems

are also envisaged for a variety of hazardous

earthbound applications such as urban search and

rescue. Recent research has pointed out that to reduce

human workload, costs, fatigue driven error and risk,

intelligent robotic systems will need to be a

significant part of mission design. However, little

attention has been paid to joint human-robot teams.

Making human-robot collaboration natural and efficient

is crucial. In particular, grounding, situational

awareness, a common frame of reference and spatial

referencing are vital in effective communication and

collaboration.

Mohammad sad d et al have proposed A Survey on Remotely

Operated Quad rotor Aerial Vehicle Using the Camera

Perspective.

This survey paper presents a mission-centric

approach to controlling the optical axis of a video

camera mounted on a camera manipulator and fixed to a

quad rotor remotely operated vehicle. A four-DOF quad

rotor, UAV model will be combined with a two-DOF camera

kinematic model to create a single system to provide a

full six DOF actuation of the camera view. This survey

work proposed exploits that all signals are described

in camera frame. The closed-loop controller is designed

based on a L yak pinot-type analysis so that the

tracking result is shown to produce Globally Uniformly

Ultimately Bounded (GUUB). Computer simulation results

are provided to demonstrate the suggested controller.

2

Patrick Doherty et al have proposed a mini unmanned

aerial vehicle (UAV): system overview and image

acquisition

The paper is to provide a broad overview of the

Unmanned Aerial Vehicle Project. The UAV project is an

ambitious, long-term basic research project with the

goal of developing technologies and functionalities

necessary for the successful deployment of a fully

autonomous UAV operating over diverse geographical

terrain containing road and traffic networks. The

project is multi-disciplinary in nature, requiring many

different research competences, and covering a broad

spectrum of basic research issues, many of which relate

to current topics in artificial intelligence. A number

of topics considered are knowledge representation

issues, active vision systems and their integration

with deliberative/reactive architectures, helicopter

modeling and control, ground operator dialogue systems,

actual physical platforms, and a number of simulation.

1.3 OBJECTIVE

The proposed system implements the vehicle that

carry the automated external defibrillator (AED) to

help the lay rescuers those are suffering from cardiac

arrest as soon as possible.

1.4 EXISTING SYSTEM

In the existing system the Quad copter is used in

the roadways which takes a huge amount of time to reach

the destination if any traffic occurs. The most

significant problem up to date has been an ambitious

development schedule coupled with very limited funds

and this ambition is followed by complexity in

calculation and designing. Quad copter will be

unbalance and lost stability in case there are

disturbance direct on it such as wind.

3

1.4.1 DISADVANTAGE OF EXISTING SYSTEM

1.The vehicle cannot be operated over a longdistance.

2.It takes time reach the destination if any trafficoccurs.

3.It can be hacked by unknown person. 4.If any problem

1.5 PROPOSED SYSTEM

In the proposed system, the Quad copter is

implemented in the airways and it is time saving. It

can reach the destination as soon as possible in case

of emergency and it is safer for close interaction. In

this project, the Quad copter do not require mechanical

linkages to vary the rotor blade pitch angle as they

spin. This simplifies the design and maintenance of the

vehicle. The Important feature is its size that is

suitable for programming from a PC platform. Capability

to move into a surface as small as a desk, both in

autonomous as remotely. It is equipped with an in-built

wireless communication module.

1.5.1 ADVANTAGE OF PROPOSED SYSTEM

1.Utilized for long distance operation. 2.Less time is needed to reach the destination. 3.If any doubts arise regarding dispatching AED a

toll free number is given to clarify that.

1.5.2 SCOPE OF PROJECT

1.Quad copter only can operate in sunny day or drycondition.

2.Quad copter is operated by brushless motor

control by electronic speed controller

4

CHAPTER 2

IMPLEMENTATION AND DESIGN

2.1 BLOCK DAIGRAM

The basic block diagram of the vehicle Section is

given in figure 2.1 .In this we are using two sections

one is monitoring unit and another is heliport unit. In

monitoring unit power supply is given to ZigBee and PC.

MAX232 forms an interface between ZigBee and PC. The

command given by PC is transmitted through ZigBee and

received by heliport unit. The receiver unit has

AT89C51 is the processing unit of the system. It reads

the data, process it and the output signal is send to

the various units like monitor, ZigBee module etc.

HELIPOTUNIT

GSM AT89C51

PCZIGBEE

Fig 2.1 Block Diagram of Monitoring Unit.

The heliport unit is shown in figure 2.2 .It

generates the control signal for units like driver

circuit which is connected to the helicopter robot.

5

The shocking device (AED) is carried by heliport

unit. When ZigBee in receiving unit receives the data

it transmit it to microcontroller using MAX232

interface and the driver circuit helps to move a

vehicle .While moving the pictures are captured by

camera is received and displayed in monitor. As soon as

the vehicle reached the rescuers by receiving the call

through GSM through the GPS location was tracked.

The procedure for applying Automated External

defibrillator (AED) is given by tele control method. A

toll free number is used if any doubts arise during

dispatching of AED.

CAMERA

AT89C ZIGBEESPEAKER 51

GPS

Fig 2.2 Block Diagram of Heliport unit

6

2.2 WORKING PRINCIPLE

Sudden cardiac arrest is the leading cause of

death worldwide. It can happen anywhere at work, at

home or anywhere else. AEDs are designed to help

someone in cardiac arrest. However, it may take a long

time to get an AED at nearest scene of victims because

AEDs are not available everywhere. Therefore, we have

proposed the UAV as a platform to save someone’s life

during cardiac arrest this robot can be characterized

by different degree of autonomy and it will executed

if fervent asks. Once the call initiated by lay

rescuers the GPS module issued to provide satellite

location information needed to find the shortest path

of victims, such as longitude/latitude coordinates and

direction. When the UAV center receives the GPS

information regarding the victim, the main server

located in the server computes the shortest path and

transmit it to the robot.

The UAV will carry an AED and follow the path for

tracing the victim until the destination has been

found. In this stage UAV is in autonomous navigation

and obstacle avoidance mode. UAV reports the current

situation and displays the motion through streaming

the video using cameras mounted on the in front arm of

the body and the other one on the arm. Such operation

method would improve the task of navigation compare to

the manual mode. Additionally, it may help to reduce

the stress on the operators because they can easily

understand what the robot is going to do and how to

send data to the robot. Although it has no human

intervention for controlling the robot but the

operator assistances till needed to deliver some

additional information.

7

CHAPTER 3COMPONENTS DESCRIPTION

HARDWARE EQUIPMENTS1.Quad copter 2.GSM 3.GPS 4.ZigBee 5.Propellers 6.Frames and arms 7.Brushless motors 8.Battery and charges 9.Electronic speed cable 10. Radio transmitter and receiver

3.1 QUAD COPTER INTRODUCTION

A quad-rotor helicopter (i.e. QUADCOPTER) is an

aircraft whose lift is generated by four rotors.

Control of such a craft is accomplished by varying the

speeds of the four motors relative to each other. Quad-

rotor crafts naturally demand a sophisticated control

system in order to allow for balanced flight.

Uncontrolled flight of a quad-rotor would be virtually

impossible by one operator, as the dynamics of such a

system demand constant adjustment of four motors

simultaneously. The goal of our project is to design

and construct a Spy copter, quad-copter capable of

Indoor-outdoor flight and hover with an on-board

wireless camera used for remote surveillance and

control.

8

Through the use of an integrated control system,this vehicle would be capable of autonomous operation,

including take-off, hover, and landing capabilities,controlled remotely by an operator and let the view the

real-time footage captured by the camera.

3.1.1 QUAD-COPTER THEORYOur Quad-copter uses four propellers, each

controlled by its own motor and electronic speed

controller. Using accelerometers we are able to measure

the angle of the Quad-copter in terms of X, Y, and Z

and accordingly adjust the RPM of each motor in order

to self-stabilize its self. The Quad-copter platform

provides stability as a result of the counter rotating

motors which result in a net moment of zero at the

centre of the Quad-copter.

Fig 3.1 Net Moment at f3=0

Using this principle we are able to adjust the speed

(RPM as a function of the voltage provided to the

motor) of each individual motor in order to correctly

manipulate Quad-copter’s yaw, pitch, and roll. Pitch

and roll can be controlled by changing the speed of the

appropriate motors, while yaw control involves delicate

balancing of all four motor functions in order to

change the moment force applied to the quad.

9

As seen from the below figure 3.2, two of the motors

i.e. motor 1 and 3 are rotating in a clockwise

direction and the other two motors i.e. motor 2 and 4

are rotating in anti-clockwise direction so as to

ensure the perfect balance at the centre of the quad-

copter.

Fig3.2 Direction of Rotation of Motors

3.1.2 THE KINETIC PRINCIPLE OF QUAD-COPTERUnlike common helicopters that have variable pitch

angle, the quad copter obtains the expected speed by

its fix pitch rotors whose speed is variable. The basic

kinetic diagram is shown below. The vertical movement

of quad copter could be realized by adjustments of the

speeds of all four rotors at the same time.

The movement along the X direction depends on theinclination on Y whose angle could be adjust by slowing

down the speeds of rotors 1 and 2, speeding up rotors 3

and 4.

The inclination also generate the acceleration

along X direction. The movement along the Y direction

depends on the inclination on X analogously.

10

Yaw movement is achieved by imbalance of the

moments generated by the four rotors. The common

helicopter has a stroke oar which could balance the

moment generated by the main rotor. However, the quad

copter could balance the moments only by each other.

The imbalance of the moments, if calculated precisely,

could generate expected yaw movement.

.Fig 3.3 The Upward Thrust Produced By All Motors

3.2 MICROCONTROLLER UNITThe microcontroller unit is used to sense the crack

using the crack sensor and to send a message to control

section in case of detection of crack and controls the

motor drivers. The microcontroller used in this project

is 8051 microcontroller.

3.2.1 INTRODUCTION

Intel first produced a microcontroller in 1976 under

the name MCS-48 which was an 8 bit microcontroller. Later

in 1980 they released a further improved version (which

is also 8 bit) under the name MCS-51. The most popular

microcontroller

11

8051 belongs to the MCS-51 family of microcontrollers

by Intel. Following the success of 8051 many other

semiconductor manufacturers released microcontrollers

under their own brand name but using the MCS-51 core.

Global companies and giants in semiconductor industry

like Microchip, Ziploc, Atmel, Philips, and Siemens

released products under their brand name. The specialty

was that all these devices could be programmed using

the same MCS-51 instruction sets. They basically

differed in support device configurations like improved

memory presence of an ADC or DAC etc. Intel then

released its first 16 bit microcontroller in 1982 under

name MCS-96.

3.2.2 AT89C51 MICROCONTROLLER PACKAGING

There is no need of explaining what each package

means you already know it. Availability of various

packages change from device to device. The most

commonly used is Dual Inline Package (40 pins) – known

popularly as DIP. 8051 is also available in QFP (Quad

Flat Package), TQFP (Thin Quad Flat Package), PQFP

(Plastic Quad Flat Package) etc.

3.2.3 AT89C51 MICROCONTROLLER PIN DIAGRAM

The below Fig 3.4 shows the AT89C51 pin diagram

which consists of four ports. The basic architecture

remains same for the MCS-51 family. In general all

microcontrollers in MCS- 51 family are represented by

XX51 where XX can take values like 80, 89 etc.

The8051 system bus composes of an 8 bit data bus

and a 16 bit address busand bus control signals.

12

3.2.4 PIN FUNCTIONS

1.Pins 1-8: Port 1 Each are input or an output. 2.Pin 9: RS a logic one on this pin disables the

microcontroller and clears the contents of registers.

The positive voltage on this pin resets the

microcontroller.

Fig 3.4 Pin diagram

3. Applying logic zero to this pin the program startsexecuting from the beginning.

4.Pins10-17: Port 3 Similar to port 1 these pins serveas general input or output.

13

5.Pin 10: RXD Serial asynchronous communication input

port or Serial synchronous communication output port.

6.Pin 11: TXD Serial asynchronous communication output

port or Serial synchronous communication clock output

port.

7.Pin 12: INT0 Interrupt 0 input pin. 8.Pin 13: INT1 Interrupt 1 input pin. 9.Pin 14: T0 Counter 0 clock input pin 10. Pin 15: T1 Counter 1 clock input pin.11. Pin 16: WR Write to external memory RAM. 12. Pin 17: RD Read from external memory RAM. 13. Pin 18, 19: X2, X1 Internal oscillator input and

output. A quartz crystal which specifies operating

frequency is connected to these pins. Later versionsof microcontrollers operation frequency is from 0 Hz

to 50 Hz.

14. Pin 20: GND Ground pin.15. Pin 21-28: Port 2 If there is no need of usage of

external memory then these port pins are configuredas general inputs/outputs. If external memory is used

the higher address byte will appear on this port.

16. Pin 29: PSEN if external ROM is used for storage of

program then a logic zero appears on it every time

the microcontroller reads a byte from memory.

17. Pin 30: ALE the microcontroller puts the loweraddress byte (A0-A7) on P0 and activates the ALE

output. After receiving signal from the ALE pin theexternal register memorizes the state of P0 and uses

it as a memory chip address. Immediately after thatthe ALU pin came back to its previous logic state and

P0 is now used as a Data Bus.

18. Pin 31: EA On applying logic zero to this pin P2

and P3 are used for data and address transmission On

applying logic one the microcontroller will use both

memories at first internal then external.

14

19. Pin 32-39: Port 0 Similar to P2 if external memoryis not in use these pins can be used as general

inputs/outputs. Otherwise, P0 is kept as addressoutput when the ALE pin is high or data output when

the ALE pin is driven low.

20. Pin 40: VCC +5V power supply given from the rectified output voltage.

3.2.5 INTERNAL ARCHITECTURE

The below Fig 3.5 shows were the bus connects all

the support devices with the central processing unit.

8051 system bus composes of an 8 bit data bus and a 16

bit address bus and bus control signals. Devices like

program memory, ports, data memory, serial interface,

interrupt control, timers, and the central processing

unit are all interfaced together through the system

bus. RxD and TxD (serial port input and output) are

interfaced with port 3.

Fig 3.5 Simplified Internal Architecture

15

3.2.6 MEMORY ORGANIZATION

Two types of architecture exist and they are

Princeton architecture and Harvard architecture.

Princeton architecture treats address memory and data

memory as a single unit (does not distinguish between

two) whereas Harvard architecture treats program memory

and data memory as separate entities. Thus Harvard

architecture demands address, data and control bus for

accessing them separately whereas Princeton

architecture does not demand any such separate bus.

8051 micro controller is based on Harvard architecture

and 8085 microprocessor is based on Princeton

architecture.

Thus 8051 has two memories: Program memory and Data memory

PROGRAM MEMORY ORGANIZATIONThe below Fig3.6 shows internal program of 4K size

and if needed an external memory can be added (by

interfacing) of size 60K maximum. So in total 64K size

memory is available for 8051 micro controller.

Fig 3.6 Program Memory Arrangement

16

It has an internal program of 4K size and if needed

an external memory can be added (by interfacing) of

size 60K maximum. So in total 64K size memory is

available for 8051 micro controller. The External

Access (EA) pin should be connected Vcc so that

instructions are fetched from internal memory

initially. When the limit of internal memory (4K) is

crossed control will automatically move to external

memory to fetch remaining instructions. If the

programmer wants to fetch instruction from external

memory only (bypassing the internal memory) then

connect External Access (EA) pin to ground (GND).

Once these bits are programmed contents of internal

memory cannot be accessed using an external circuitry.

However locking the software is not possible if

external memory is also used to store the software

code. Only internal memory can be locked and protected.

Once locked these bits can be unlocked only by a

memory-erase operation which in turn will erase the

programs in internal memory too.

AT89C51 is capable of pipelining. Pipelining makes

a processor capable of fetching the next instruction

while executing previous instruction. It’s something

like multi-tasking doing more than one operation at a

time. 8051 is capable of fetching first byte of the

next instruction while executing the previous

instruction.

DATA MEMORY ORGANIZATION

The below Fig 3.7 shows MCS-51 family, AT89C51 has

128 bytes of internal data memory and it allows

interfacing external data memory of maximum size up to

64K. So the total size of data memory in 8051 can be up

to 64K (external) + 128 bytes (internal).

17

Fig 3.7 Data Memory Organization

3.2.7 SCHEMATIC AND FEATURES

The below Fig 3.8 shows 3 system inputs, 3 control

signals and 4 ports (for external interfacing). A Vcc

power supply and ground.

Fig 3.8 Block for schematic input and outputs.

18

XTAL 1 and XTAL 2 are for the system clock inputs

from crystal clock circuit. RESET input is required to

initialize microcontroller to default/desired values

and to make a new start.

There are 3 control signals EA, PSEN and ALE. These

signal is known as External Access (EA), Program Store

Enable (PSEN) and Address Latch Enable (ALE) are used

for external memory interfacing.

3.2.8 SYSTEM CLOCK

The connection shown in Fig 3.9 is the connections toXTAL 1 and XTAL 2.

Fig 3.9 Clock Circuit of AT89C51.

In some cases external clock sources are used and

you can see the various connections. Clock frequency

limits (maximum and minimum) may change from device to

device. Standard practice is to use 12MHz frequency. If

serial communications are involved then its best to use

11.0592 MHz frequency.

19

3.2.9 RESET CIRCUIT

AT89C51 can be reset in two ways Fig 3.10 is power-

on reset – which resets the 8051 when power is turned

ON and Fig 3.11 manual reset – in which a reset happens

only when a push button is pressed manually. Two

different reset circuits are shown above. A reset

doesn’t affect contents of internal RAM. For reset to

happen the reset input pin (pin 9) must be active high

for at least 2 machine cycles.

During a reset operation Program counter is cleared

and it starts from 00H, register bank #0 is selected as

default, Stack pointer is initialized to 07H

Fig 3.10 Power on Reset Circuit Fig 3.11 Manual Reset Circuit

20

3.3 GSM3.3.1 DEFINITION

Global system for mobile communication (GSM) is

a globally accepted standard for digital cellular

communication. GSM is the name of a standardization

group established in 1982 to create a common European

mobile telephone standard that would formulate

specifications for a pan-European mobile cellular radio

system operating at 900 MHz.

3.3.2 THE GSM NETWORK

GSM provides recommendations, not requirements.

The GSM specifications define the functions and interface

requirements in detail but do not address the hardware.

The reason for this is to limit the designers as little

as possible but still to make it possible for the

operators to buy equipment from different suppliers. The

GSM network is divided into three major systems: the

switching system (SS), the base station system (BSS), and

the operation and support system (OSS). The basic GSM

network elements are shown in below figure.

Fig 3.12 GSM Network Elements

21

3.3.3 GSM MODEM

A GSM modem is a wireless modem that works with a GSM

wireless network. A wireless modem behaves like a dial-up

modem. The main difference between them is that a dial-up

modem sends and receives data through a fixed telephone

line while a wireless modem sends and receives data

through radio waves.

A GSM modem can be an external device or a PC

Card / PCMCIA Card. Typically, an external GSM modem is

connected to a computer through a serial cable or a USB

cable. A GSM modem in the form of a PC Card / PCMCIA

Card is designed for use with a laptop computer. It

should be inserted into one of the PC Card / PCMCIA

Card slots of a laptop computer. Like a GSM mobile

phone, a GSM modem requires a SIM card from a wireless

carrier in order to operate.

As mentioned in earlier sections of this SMS

tutorial, computers use AT commands to control modems.

Both GSM modems and dial-up modems support a common set

of standard AT commands. IT can use a GSM modem just

like a dial-up modem. In addition to the standard AT

commands, GSM modems support an extended set of AT

commands. These extended AT commands are defined in the

GSM standards. With the extended AT commands,

• Reading, writing and deleting SMS messages. • Sending SMS messages. • Monitoring the signal strength. • Monitoring the charging status and charge level of

the battery. • Reading, writing and searching phone book entries.

The number of SMS messages that can be processed bya GSM modem per

minute is very low -- only about six to ten SMS messages per minute.

22

Fig 3.13 Applications of GSM Modem

3.3.4. FUNCTIONS OF GSM

The GSM/GPRS Modem comes with a serial interface

through which the modem can be controlled using AT

command interface. An antenna and a power adapter are

provided.

The basic segregation of working of the modem is as

under

1.Voice calls 2.SMS 3.GSM Data calls

23

VOICE CALLS

` Voice calls are not an application area to be

targeted. In future if interfaces like a microphone

and speaker are provided for some applications then

this can be considered.

SMS

1.SMS is an area where the modem can be used

to provide features like: Pre-stored SMS

transmission.

2.These SMS can be transmitted on certain

trigger events in an automation system

3.SMS can also be used in areas where smalltext information has to Be sent.

The transmitter can be an automation system or

machines like vending machines, collection machines or

applications like positioning systems where the

navigator keeps on sending SMS at particular time

intervals. SMS can be a solution where GSM data call or

GPRS services are not available.

3.3.5 APPLICATIONS OF GSM

ACCESS CONTROL DEVICES

Now access control devices can communicate with

servers and security staff through SMS messaging.

Complete log of transaction is available at the head-

office Server instantly without any wiring involved and

device can instantly alert security personnel on their

mobile phone in case of any problem.

24

TRANSACTION TERMINALS

EDC machines, POS terminals can use SMS messaging

to confirm transactions from central servers. The main

benefit is that central server can be anywhere in the

world. Today you need local servers in every city with

multiple telephone lines. You save huge infrastructure

costs as well as per transaction cost.

SUPPLY CHAIN MANAGEMENT

Today SCM require huge IT infrastructure with

leased lines, networking devices, data center,

workstations and still you have large downtimes and

high costs. You can do all this at a fraction of the

cost with GSM M2M technology. A central server in your

head office with GSM capability is the answer; you can

receive instant transaction data from all your branch

officers, warehouses and business administration.

3.3.6 FEATURES OF GSM COMMUNICATION

Features of GSM will be more cost-effective

than other communication systems.

SHORT DATA SIZE

You data size per transaction should be small like

1-3 lines. e.g. banking transaction data, sales/purchase

data, consignment tracking data, updates. These small but

important transaction data can be sent through SMS

messaging which cost even less than a local telephone

call or sometimes free of cost worldwide. Hence with

negligible cost you are able to send critical information

to your head office located anywhere in the world from

multiple points. It can also transfer faxes, large data

through GSM but this will be as or more costly compared

to landline networks.

25

MULTIPLE REMOTE DATA COLLECTION POINTS

If you have multiple data collections points

situated all over your city, state, country or

worldwide you will benefit the most. The data can be

sent from multiple points like your branch offices,

business associates, warehouses, and agents with

devices like GSM modems connected to PCs, GSM

electronic terminals and Mobile phones. Many a times

some places like warehouses may be situated at remote

location may not have landline or internet but you will

have GSM network still available easily.

HIGH UPTIME

If your business require high uptime and

availability GSM is best suitable for you as GSM mobile

networks have high uptime compared to landline,

internet and other communication mediums. Also in

situations where you expect that someone may sabotage

your communication systems by cutting wires or taping

landlines, you can depend on GPS wireless communication

system:

LARGE TRANSACTION VOLUMES

GSM SMS messaging can handle large number of

transaction in a very short time. You can receive large

number SMS messages on your server like e-mails without

internet connectivity. E-mails normally get delayed a

lot but SMS messages are almost instantaneous for

instant transactions.

Consider situation like shop owners doing credit

card transaction with GSM technology instead of

conventional landlines. Time you find local transaction

servers busy as these servers use multiple telephone

lines to take care of multiple transactions, whereas

one GSM connection is enough to handle hundreds of

transaction.

26

MOBILITY AND QUICK INSTALLATION

GSM technology allows mobility, GSM terminals, modems

can be just picked and installed at other location unlike

telephone lines. Also you can be mobile with GSM

terminals and can also communicate with server using your

mobile phone. You can just purchase the GSM hardware like

modems, terminals and mobile handsets, insert SIM cards,

configure software and ready for GSM communication.

3.3.7 MAX 232

INTRODUCTION

MAX-232 is primary used for people building

electronics with an RS-232 interface. Serial RS-232

communication works with voltages (-15V ... -3V for

high) and +3V ... +15V for low) which are not

compatible with normal computer logic voltages. To

receive serial data from an RS-232 interface the

voltage has to be reduced, and the low and high voltage

level inverted. In the other direction (sending data

from some logic over RS-232) the low logic voltage has

to be "bumped up", and a negative voltage has to be

generated, too.

A standard serial interfacing for PC, RS232C,

requires negative logic, i.e., logic '1' is -3V to -12V

and logic '0' is +3V to +12V. To convert TTL logic,

say, TxD and RxD pins of the uC chips thus need a

converter chip. A MAX232 chip has long been using in

many uC boards.

It provides 2-channel RS232C port and requires

external 10uF capacitors. Carefully check the polarity

of capacitor when soldering the board.

27

Fig 3.14 Pin Description of Max 232

A standard serial interfacing for PC, RS232C,

requires negative logic, i.e., logic '1' is -3V to -12V

and logic '0' is +3V to +12V. To convert TTL logic,

say, TxD and RxD pins of the uC chips thus need a

converter chip. A MAX232 chip has long been using in

many uC boards. It provides 2-channel RS232C port and

requires external 10uF capacitors. Carefully check the

polarity of capacitor when soldering the board.

RS232 is an asynchronous serial communications

protocol, widely used on computers. Asynchronous means

it doesn't have any separate synchronizing clock

signal, so it has to synchronize itself to the incoming

data - it does this by the use of 'START' and 'STOP'

pulses.

The signal itself is slightly unusual for

computers, as rather than the normal 0V to 5V range, it

uses +12V to -12V - this is done to improve

reliability, and greatly increases the available range

it can work over - it isn't necessary to provide this

exact voltage swing, and you can actually use the PIC's

0V to 5V voltage swing with a couple of resistors to

make a simple RS232 interface which will usually work

well, but isn't guaranteed to work with all serial

ports.28

AN RS232 TO TTL LEVEL CONVERTER

The RS232/DB9 is designed to convert TTL level

signals into RS232 level signals. This cable allows you

to connect a TTL level device, such as the serial port

on a Micro-controller, to the serial port of a personal

computer. The conversion circuit is housed inside the

DB9 connector shell. Power is supplied from the micro-

controller board.

The board is based on the Maxim MAX3221CAE

interface chip. This chip draws a mere 1mA of current

when there are no RS-232 signals connected to the part.

With the exception of the DB9 connector and the wire,

all parts on this board are surface mounted, and

require care during assembly. The mounting of surface

mount parts is not difficult, but does require a steady

hand. A magnifying glass or other visual aid may be

helpful. You also need some electronic paste flux.

3.4 GPS INTRODUCTION

The Global Positioning System (GPS) is a satellite-

based navigation system made up of a network of 24

satellites placed into orbit by the U.S. Department of

Defense. GPS was originally intended for military

applications, but in the 1980s, the US Government made

the system available for civilian use .

GPS works in any weather conditions, anywhere in

the world, 24 hours a day. There are no subscription

fees or setup charges to use GPS.

The Global Positioning System was conceived in 1960

under the auspices of the U.S. Air Force, but in 1974

the other branches of the U.S. military joined the

effort. The first satellites were launched into space

in 1978. The System was declared fully operational in

April 1995. The Global Positioning System consists of

24 satellites, that circle the globe once every 12

hours, to provide worldwide position, time and velocity

information.

29

Fig 3.15 GPS PCB Board Diagram.

GPS makes it possible to precisely identify

locations on the earth by measuring distance from the

satellites. GPS allows you to record or create

locations from places on the earth and help you

navigate to and from those places. Originally the

System was designed only for military applications and

it wasn’t until the 1980’s that it was made available

for civilian use also.

3.4.1 WORKING OF GPS

GPS satellites circle the earth twice a day in a very

precise orbit and transmit signal information to earth.

There are 24 satellites that make up the GPS space

segment that are orbiting the earth at approximately

19,000 kilometers above us. They are constantly moving,

making two complete orbits in less than 24 hours. These

satellites are travelling at speeds of roughly 11,000

kilometers per hour. GPS receivers take this information

and use triangulation to calculate the user's exact

location. Essentially, the GPS receiver compares the time

a signal was transmitted by a satellite with the time it

was received. The time difference tells the GPS receiver.

30

How far away the satellite is. Now, with distance

measurements from a few more satellites, the receiver

can determine the user's position and display it on the

unit's electronic map. A GPS receiver must be locked on

to the signal of at least three satellites to calculate

a 2D position (latitude and longitude) and track

movement. With four or more satellites in view, the

receiver can determine the user's 3D position

(latitude, longitude and altitude).

Once the user's position has been determined, the

GPS unit can calculate other information, such as

speed, bearing, track, trip distance, distance to

destination, sunrise and sunset time and more.

3.4.2 THREE SEGMENTS OF GPS

THE SPACE SEGMENT

The space segment consists of 24 satellites

circling the earth at 12,000 miles in altitude. This

high altitude allows the signals to cover a greater

area. The satellites are arranged in their orbits so a

GPS receiver on earth can always receive a signal from

at least four satellites at any given time.

Each satellite transmits low radio signals with a

unique code on different frequencies, allowing the GPS

receiver to identify the signals. The main purpose of

these coded signals is to allow for calculating travel

time from the satellite to the GPS receiver. The travel

time multiplied by the speed of light equals the

distance from the satellite to the GPS receiver. Since

these are low power signals and won’t travel through

solid objects, it is important to have a clear view of

the sky.

31

Fig 3.16 Three Segments of GPS.

THE CONTROL SEGMENT

The control segment tracks the satellites and then

provides them with corrected orbital and time

information. The control segment consists of four

unmanned control stations and one master control

station. The four unmanned stations receive data from

the satellites and then send that information to the

master control station where it is corrected and sent

back to the GPS satellites.

THE USER SEGMENT

The user segment consists of the users and their

GPS receivers. The number of simultaneous users is

limitless.

3.4.3 HOW GPS WORKS

When a GPS receiver is turned on, it first downloads

orbit information of all the satellites. This process,

the first time, can take as long as 12.5 minutes, but

once this information is downloaded; it is stored in the

receiver’s memory for future use.

Even though the GPS receiver knows the precise

location of the satellites in space, it still needs to

know the distance from each satellite it is receiving a

signal from. That distance is calculated, by the

receiver, by multiplying the velocity of the

transmitted signal by the time it takes the signal to

reach the receiver. The receiver

32

already knows the velocity, which is the speed of a

radio wave or 186,000 miles per second (the speed of

light).

To determine the time part of the formula, the

receiver matches the satellites transmitted code to its

own code, and by comparing them determines how much it

needs to delay its code to match the satellites code.

This delayed time is multiplied by the speed of light

to get the distance.

The GPS receiver’s clock is less accurate than the

atomic clock in the satellite; therefore, each distance

measurement must be corrected to account for the GPS

receiver’s internal clock error.

3.5 ZIGBEE

3.5.1 ZIGBEE PHYSICAL LAYER

ZigBee is a wireless technology developed as an

open global standard to address the unique needs of

low-cost, low-power wireless M2M networks. The ZigBee

standard operates on the IEEE 802.15.4 physical radio

specification and operates in unlicensed bands

including 2.4 GHz, 900 MHz and 868 MHz.

The 802.15.4 specification upon which the ZigBee

stack operates gained ratification by the Institute of

Electrical and Electronics Engineers (IEEE) in 2003.

The specification is a packet-based radio protocol

intended for low-cost, battery-operated devices. The

protocol allows devices to communicate in a variety of

network topologies and can have battery life lasting

several years.

3.5.2 THE ZIGBEE ADVANTAGE

The ZigBee protocol is designed to communicate data

through hostile RF environments that are common in

commercial and industrial applications.

33

ZigBee protocol features include:

1.Support for multiple network topologies such as

point-to-point, point-to-multipoint and mesh

networks.

2.Low duty cycle – provides long battery life. 3.Low latency. 4.Up to 65,000 nodes per network. 5.128-bit AES encryption for secure data

connections. 6.Collision avoidance, retries and

acknowledgements.

Fig 3.17 ZigBee module

3.5.3 MESH NETWORKS

A key component of the ZigBee protocol is the

ability to support mesh networking. In a mesh network,

nodes are interconnected with other nodes so that

multiple pathways connect each node. Connections

between nodes are dynamically updated and optimized

through sophisticated, built-in mesh routing table.

Mesh networks are decentralized in nature; each

node is capable of self-discovery on the network. Also,

as nodes leave the network, the mesh topology allows

the nodes to reconfigure routing paths based on the new

network structure.

34

The characteristics of mesh topology and ad-hoc routing

provide greater stability in changing conditions or

failure at single nodes.

3.5.4 ZIGBEE APPLICATIONS

ZigBee enables broad-based deployment of wireless

networks with low-cost, low-power solutions. It provides

the ability to run for years on inexpensive batteries for

a host of monitoring and control applications. Smart

energy/smart grid, AMR (Automatic Meter Reading),

lighting controls, building automation systems, tank

monitoring, HVAC control, medical devices and fleet

applications are just some of the many spaces where

ZigBee technology is making significant advancements.

3.5.5 DIGI ZIGBEE TECHNOLOGY

Digi is a member of the ZigBee Alliance and has

developed a wide range of networking solutions based on

the ZigBee protocol. XBee and XBee-PRO modules and

other XBee-enabled devices provide an easy-to-implement

solution that provides functionality to connect to a

wide variety of devices.

3.6 PROPELLERSA propeller is a type of fan that transmits power

by converting rotational motion into thrust. A pressure

difference is produced between the forward and rear

surfaces of the airfoil-shaped blade, and air or water

is accelerated behind the blade. Propeller dynamics can

be modelled by both Bernoulli’s principle.

3.6.1 AIRFOILAn airfoil or aero foil is the shape of a wing or

blade (of a propeller, rotor or turbine) or sail as

seen in cross-section. An airfoil-shaped body moved

through a fluid produces an aerodynamic force. The

component of this force perpendicular to

35

the direction of motion is called lift. The componentparallel to the direction of motion is called drag.

Subsonic flight airfoils have a characteristic shapewith a rounded leading edge, followed by a sharp

trailing edge, often with asymmetric camber. Foils ofsimilar function designed with water as the working

fluid are called hydrofoils.

The lift on an airfoil is primarily the result of

its angle of attack and shape (in particular its

camber). When either is positive, the resulting flow

field about the airfoil has a higher average velocity

on the upper surface than on the lower surface.

This velocity difference is necessarily accompanied

by a pressure difference, via Bernoulli’s principle for

incompressible in viscid flow, which in turn produces

the lift force. The lift force can also be related

directly to the average top/bottom velocity difference,

without invoking the pressure, by using the concept of

circulation and the Kutta-Joukowski theorem.

3.6.2 STRUCTURE OF AN AIRFOIL 1.Angle of attack is the angle between the

lifting body’s reference line(chord) and the

oncoming flow.

2.The chord of an airfoil is the imaginary

straight line drawn through theairfoil from itsleading edge to its trailing edge.

3.Camber is the asymmetry between the top and

the bottom surfaces ofan airfoil.

4.The trailing edge is the back of the airfoil—

the place at which theairflow over the upper

surface of the airfoil joins the airflow over

the lower surface of the airfoil.

36

Fig 3.18 Structure of Airfoil

5 The leading edge is the “front” of the airfoil—

the portion that meetsthe air first.

3.6.3 PRINCIPLE AND WORKING

The principle and working of a propeller is based

on Bernoulli’s Principle & Newton’s Third Law.

Bernoulli’s principle states that for an in viscid

flow, an increase in the speed of the fluid occurs

simultaneously with a decrease in pressure or a

decrease in the fluid’s potential energy. Newton’s

third law states that every action has an equal and

opposite reaction.

An aerofoil is shaped so that air flows faster over

the top than under the bottom. There is, therefore, a

greater pressure below the aerofoil than above it.This

difference in pressure produces the lift. Lift

coefficient is a dimensionless coefficient that relates

the lift generated by an aerodynamic body such as a

wing or complete aircraft, the dynamic pressure of the

fluid flow around the body, and a reference area

associated with the body.

37

3.6.4 AERODYNAMIC FORCES ACTING ON THE AIRFOILLift and drag are considered to be the two

aerodynamic forces that are acting upon the airfoil as

shown in the below figure.

Lift is defined to be the component of this force

that is perpendicular to the oncoming flow direction.

Drag is defined to be the component of the surface

force parallel to the flow direction. In fluid

dynamics, drag (sometimes called air resistance or

fluid resistance) refers to forces that oppose the

relative motion of an object through a fluid (a liquid

or gas).

Fig 3.19 Forces acting on an Air foil

38

3.6.5 PITCH OF A PROPELLER

Pitch of a propeller is normally described as the

distance travelled per rotation, assuming there is no

slip ..Low pitch yields good low speed acceleration (and

climb rate in an aircraft) while high pitch optimizes

high speed performance and economy.

Fig 3.20 Pitch of a Propeller

Blade pitch or simply pitch refers to turning the

angle of attack of the blades of a propeller or

helicopter rotor into or out of the wind to control the

production or absorption of power. Wind turbines use

this to adjust the rotation speed and the generated

power. A propeller of a ship uses this effect to

control the ship’s speed without changing the rotation

of the shaft and to increase the efficiency of

streaming fluids. In aircraft, blade pitch is usually

described as “coarse” for a high angle of attack, and

“fine” for a low angle of attack. Blade pitch is

normally described in units of distance/rotation

assuming no slip. Blade pitch acts much like the

gearing of the final drive of a car.

Low pitch yields good low speed acceleration (and

climb rate in an aircraft) while high pitch optimizes

high speed performance and economy. Because the

velocity of a propeller blade varies from the hub to

the tip, they must be of twisted form in order for the

pitch to remain constant along the length of the blade.

39

This is typical of all but the crudest propellers.

It is quite common in aircraft for the propeller to be

designed to vary pitch in flight, optimizing both

cruise and takeoff performance.

3.6.6 USES OF PROPELLERS

We have used 3 Blade, 9×5 pitch rotating and

counter rotating propellers. Benefits of using a 3

blade propeller over 2 blades is that we get more blade

area because of which the blade can transfer more power

onto the air, thus providing more lift. We are using

two different kinds of blades one rotating in clockwise

directions and other rotating in anti-clockwise

direction, thus producing force in opposite directions.

3.7 FRAMES AND ARMS

Arms also play a vital role in the fight against

vibrations, which can cause a number of different

issues. Flight controllers, with their sensitive

barometers and gyroscopes, do not generally react well

to incessant shaking. Jostle them too much through a

poor setup and you could see erratic behaviour,

sometimes bad enough to cause crashes. Vibrations are

also the dread of anyone hoping to use a camera on a

multi-rotor. The shaking ruins footage through an

artefact referred to as "jell", wavy, headache-inducing

distortion formed as a result of progressive scanning.

Fig 3.21 Diagram of Frame40

If the arms are too much flex, they can reverberate

and create harmonics that are transferred across the

multi-rotor. On the other hand, arms that are too stiff

directly pass on vibrations without any dampening,

resulting in the same problems. There is a fine balance

to be found.

The scale of a multi-rotor is often denoted by the

horizontal width of the frame assembly, including its

arms. The standard measurement is taken in millimetres

from motor to motor through the centre of the frame. If

a model includes numbers in the title, they probably

refer to this measurement. A DJI F450 is around 450 mm

across, for example. The F330 is 330 mm, and so on.

3.8 DC MOTORSA DC motor is an electric motor that runs on direct

current (DC) electricity. In any electric motor,

operation is based on simple electromagnetism. A current-

carrying conductor generates a magnetic field; when this

is then placed in an external magnetic field, it will

experience a force proportional to the current in the

conductor, and to the strength of the external magnetic

field. As you are well aware of from playing with magnets

as a kid, opposite (North and South) polarities attract,

while like polarities (North and North, South and South)

repel. The internal configuration of a DC motor is

designed to harness the magnetic interaction between a

current-carrying conductor and an external magnetic field

to generate rotational motion.

A dc motor can be broadly classified into two distinguished types of motors namely

1. Brushed dc motor 2. Brushless dc motor

41

3.8.1 FLEMING’S LEFT HAND RULE

Fleming’s left hand rule (for motors), is a visual

mnemonics that is used for working out which way an

electric motor will turn. The term was coined by John

Ambrose Fleming in the late 19th century. When an

electric current flows in a wire, and an external

magnetic field is applied across that flow, the wire

experiences a force perpendicular both to that field,

and to the direction of the current flow. A left hand

can be held, as shown in the illustration, so as to

represent three mutually orthogonal axes on the thumb,

first finger and middle finger. It is then just a

question of remembering which finger represents which

quantity (electric current, magnetic field and

mechanical force), and whether the right hand should be

used instead of the left.

3.8.2 Working of BRUSHLESS DC MOTOR

Brushless DC motors (BLDC motors, BL motors) also

known as electronically commutated motors (ECMs, EC

motors) are synchronous electric motors powered by

direct-current (DC) electricity and electronic

commutation systems, rather mechanical commutators and

brushes.

Fig 3.22 Working of Brushless Motors

42

The current-to-torque and frequency-to-speed

relationships of BLDC motors are linear. BLDC motors

may be described as stepper motors, with fixed

permanent magnets and possibly more poles on the rotor

than the stator, or reluctance motors. The latter may

be without permanent magnets, just poles that are

induced on the rotor then pulled into alignment by

timed stator windings. However, the term stepper motor

tends to be used for motors that are designed

specifically to be operated in a mode where they are

frequently stopped with the rotor in a defined angular

position; this page describes more general BLDC motor

principles, though there is overlap. Now the movement

of the magnet in the center depends on the direction of

flow of current in the coil as shown in the above

figure. The continuous movement of the magnet is

ensured by Left hand rule for the coils.

3.8.3 LEFT HAND RULE FOR THE COILS

The left hand rule states that grasp the coil in

your left hand, with your finger wrapped around in the

direction of the current. Your thumb will point towards

the north pole of the coil.

3.8.4 BRUSHLESS VS BRUSHED DC MOTOR

Limitations of brushed DC motors overcome by BLDC

motors include lower efficiency and susceptibility of the

commutator assembly to mechanical wear and consequent

need for servicing, at the cost of potentially less

rugged and more complex and expensive control

electronics. A BLDC motor has permanent magnets which

rotate and a fixed armature, eliminating the problems of

connecting current to the moving armature. An electronic

controller replaces the brush/commutator assembly of the

brushed DC motor, which continually switches the phase to

the windings to keep the motor turning. The controller

performs similar timed power distribution by using a

solid-state circuit rather than the brush/commutator

system.

43

BLDC motors offer several advantages over brushed DC

motors, including more torque per weight and efficiency,

reliability, reduced noise, longer lifetime (no brush and

commutator erosion), elimination of ionizing sparks from

the commutator, more power, and overall reduction of

electromagnetic interference (EMI).

With no windings on the rotor, they are not

subjected to centrifugal forces, and because the

windings are supported by the housing, they can be

cooled by conduction, requiring no airflow inside the

motor for cooling. This in turn means that the motor’s

internals can be entirely enclosed and protected from

dirt or other foreign matter.

The maximum power that can be applied to a BLDC

motor is exceptionally high, limited almost exclusively

by heat, which can weaken the magnets. A BLDC motor’s

main disadvantage is higher cost, which arises from two

issues. First, BLDC motors require complex electronic

speed controllers to run. Brushed DC motors can be

regulated by a comparatively simple controller, such as

a rheostat (variable resistor).

However, this reduces efficiency because power is

wasted in the rheostat. Second, some practical uses

have not been well developed in the commercial sector.

For example, in the Radio Control (RC) hobby, even

commercial brushless motors are often hand-wound while

brushed motors use armature coils which can be

inexpensively machine-wound.

44

Fig 3.23 Brushless Motors

BLDC motors are often more efficient at converting

electricity into mechanical power than brushed DC

motors. This improvement is largely due to the absence

of electrical and friction losses due to brushes. The

enhanced efficiency is greatest in the no-load and low-

load region of the motor’s performance curve.

The number of permanent magnets in the rotor does

not match the number of stator poles, however. The

difference between the number of magnet poles and the

number of stator poles provides an effect that can be

understood as similar to planetary gear ingle in

efficiency.

3.9 RADIO TRANSMITTER AND RECEIVER

3.9.1 TRANSMITTER (TX)

In electronics and telecommunications a radio

transmitter is an electronic device which, with the aid

of an antenna, produces radio waves. The transmitter

itself generates a radio frequency alternating current,

which is applied to the antenna. When excited by this

alternating current, the antenna radiates radio waves.

The term transmitter is usually limited to equipment that

generates radio waves

45

for communication purposes; or radiolocation, such as

radar and navigational transmitters. A transmitter can

be a separate piece of electronic equipment, or an

electrical circuit within another electronic device. A

transmitter and receiver combined in one unit is called

a transceiver.

The term transmitter is often abbreviated “XMTR” or

“TX” in technical documents. The purpose of most

transmitters is radio communication of information over

a distance. The information is provided to the

transmitter in the form of an electronic signal, such

as an audio (sound) signal from a microphone, a video

(TV) signal from a TV camera, or in wireless networking

devices a digital signal from a computer. The

transmitter combines the information signal to be

carried with the radio frequency signal which generates

the radio waves, which is often called the carrier.

This process is called modulation.

A radio transmitter is an electronic circuit which

transforms electric power from a battery or electrical

mains into a radio frequency alternating current, which

reverses direction millions to billions of times per

second. The energy in such a rapidly-reversing current

can radiate off a conductor (the antenna) as

electromagnetic waves (radio waves).

3.9.2 RECEIVER (RX)

A radio receiver is an electronic circuit that

receives its input from an antenna, uses electronic

filters to separate a wanted radio signal from all other

signals picked up by this antenna, amplifies it to a

level suitable for further processing, and finally

converts through demodulation and decoding the signal

into a form usable for the consumer, such as sound,

pictures, digital data, measurement values, navigational

positions, etc. Demodulation is the act of extracting the

original information-bearing

46

signal from a modulated carrier wave. A demodulator is

an electronic circuit that is used to recover the

information content from the modulated carrier wave.

The receiver in information theory is the receiving

end of a communication channel. It receives decoded

messages/information from the sender, who first encoded

them. Sometimes the receiver is modeled so as to

include the decoder. Real-world receivers like radio

receivers cannot be expected to receive as much

information as predicted by the noisy channel coding

theorem.

3.9.3 HKT6A TRANSMITTER

HKT6A transmitter is used is 6 channel, FM

modulating with a 2.4 GHz frequency band, the frequency

at which it transmits the modulated signal. the signal

transmitted by the transmitter is received by a HKT6A

receiver which de-modulates the signal to get the

original signal.

SPECIFICATIONS OF HKT6A TRANSMITTER

1.channel 2.fm modulation type 3.2.4ghz frequency band

4.power resource 1.5v * 8 ‘‘aa’’ battery 5.gfsk program type 6.led voltage display 7.weight : 575g 8.size : 189*97*218 mm 9.26 mm antenna length 10. Aileron rate switch11. Elevator dual rate switch

47

3.9.4 MODES OF A TRANSMITTER

Modes of a transmitter hk-t6a specify the working

of the transmitter, where the left gauge upward

movement specifies the throttle necessary for the lift.

The left gauge left-right movement specifies the yaw

angle.

Further the right gauge upward movement is for

controlling the pitch and the left-right movement to

control the roll. All the above explained specifies the

modes of transmitter necessary for controlling the

quad-copter in the air.

Fig 3.24 HKT6ATransmitter – Mode of Operation

A radio transmitter is an electronic circuit which

transforms electric power from a battery or electrical

mains into a radio frequency alternating current, which

reverses direction millions to billions of times per

second. The energy in such a

48

rapidly-reversing current can radiate off a conductor

(the antenna) as electromagnetic waves (radio waves).

Transmitter is used to modulate a original signal

onto the carrier wave, thus generating radio waves that

are transmitted to the receiver, which upon receive De-

modulates the signal and retrieve the original intended

signal.

3.9.5 HKT6A RECEIVER

SPECIFICATIONS OF HKT6A RECEIVER

1.channel 2.fm modulation type 3.2.4ghz frequency band 4.power resource 1.5v * 4 ‘‘aa’’ battery 5.gfsk program type 6.weight : 12g 7.size : 45*23*13.5 mm

Fig 3.25 HKT6A Receiver

49

3.10 BATTERY AND CHARGERS:The battery is an essential component of almost all

aircraft electrical systems. Batteries are used to

start engines and auxiliary power units, to provide

emergency backup power for essential avionics

equipment, to assure no-break power for navigation

units and fly-by-wire computers, and to provide ground

power capability for maintenance and preflight

checkouts. Many of these functions are mission

critical, so the performance and reliability of an

aircraft battery is of considerable importance.

Initially lead batteries and nickel-cadmium were used

but lately non-rechargeable lithium batteries, smaller

in size and with longer duration without maintenance

(up to 5 years), are rapidly replacing them.

Other important requirements include environmental

ruggedness, a wide operating temperature range, ease of

maintenance, rapid recharge capability, and tolerance

to abuse. Historically, only a few types of batteries

have been found to be suitable for aircraft

applications. Until the 1950s, vented lead-acid (VLA)

batteries were used exclusively [Earwicker, 1956]. In

the late 1950s, military aircraft began converting to

vented nickel-cadmium (VNC) batteries, primarily

because of their superior performance at low

temperature.

Fig 3.26 Diagram of Battery

50

3.11 ELECTRONIC SPEED CABLE

The ESCs are connected to the battery in parallel

via a wiring harness. The other side of the ESCs are

connected to the four motors. Each ESC’s BEC (battery

elimination circuit) is connected to the appropriate

motor pins on the flight control board. Connections are

made from the flight control board to the receiver for

power, pitch, roll, throttle, yaw, etc. To monitor the

charge level of my battery I connect a little

monitor/alarm directly to the battery’s balanced charge

connector.

Fig 3.26 ESC

3.12 DEFIBRILLATOR

The term refers to a portable and lightweight

computerized device that incorporates rhythm analysis

and defibrillation systems and uses voice and/or visual

prompts to guide lay rescuers and healthcare providers

to safely defibrillate victims of cardiac arrest due to

VF or

Pulseless VT.There are two types of AED: the semi-automatic that

indicates the need for defibrillation but requires that

the operator deliver the shock by pushing a button and

the fully automatic Cardiac Defibrillation. Basically

these devices consist of a

51

battery, a capacitor, electrodes and an electricalcircuit designed to analyze the rhythm and send an

electric shock if is needed. The electrical shockdelivered to the patient is generated by high voltage

circuits from energy stored in a capacitor which canhold up to 7 kV of electricity. The energy delivered by

this system can be anywhere from 30 to 400 joules.

Electrodes are the components through which the

defibrillator collects information for rhythm analysis

and delivers energy to the patient's heart. Many types

of electrodes are available including hand-held

paddles, internal paddles, and self-adhesive disposable

electrodes. In general, disposable electrodes are

preferred in emergency settings because they increase

the speed of shock and improve defibrillation

technique.

The typical controls on an AED include a power

button, a display screen on which trained rescuers can

check de heart rhythm and a discharge button.

Defibrillators that can be operated manually have also

an energy select control and a charge button.

Certain defibrillators have special controls for

internal paddles or disposable electrodes.

Fig 3.27 Defibrillators52

CHAPTER 4

SOFTWARE TOOLSSoftware is used to compile the coding of the

desired application for the corresponding embedded

system.

4.1 KEIL MICROVISION3:This is the embedded C compiler which is compatible

for the 8051 microcontroller to compile the code.

Keil Software makes C compilers, macro assemblers,

real-time kernels, debuggers, simulators, integrated

environments and evaluation boards for the 8051, 251,

ARM and XC16x/C16x/ST10 microcontroller families.

Keil Software provides you with software development

tools for the 8051 family of microcontrollers. With

these tools you can generate embedded applications for

the multitude of 8051 derivatives. Keil provides

following tools for 8051 development

1.C51 Optimizing C Cross Compiler. 2.A51 Macro Assembler. 3.8051 Utilities (linker, object file converter,

library manager). 4.Source-Level Debugger/Simulator.

5.µVision for Windows Integrated DevelopmentEnvironment.

The keil 8051 tool kit includes three main tools, assembler, compiler and linker.

1.An assembler is used to assemble your 8051 assemblyprogram

2.A compiler is used to compile your C source codeinto an object file

3.A linker is used to create an absolute object

module suitable for your in-circuit emulator.

53

CHAPTER 5RESULTS AND CONCLUSION

5.1 EXPREMENTAL RESULTS:

Fig 5.1 Prototype of Quad Copter

The figure 5.1shows the normal and flying mode of

the quad copter controlled by remote operation which

carry’s the defibrillator which helps the lay rescuers

from cardiac arrest as a first aid.

Fig 5.2 GPS Screen Shot

The screen shows the GPS longitude latitude which

displayed on the monitor where the quad copter

located.

54

Fig 5.3 GSM Screen Shot

When the call arrives from the rescuers location

of them is founded by the tracking with GSM

5.2 CONCLUSION AND FUTURE WORK

In order to overcome the difficulties in

conventional operation and to manage the speed of

vehicle the quad copter should be designed perfectly.

the one great advancement of the system is the speed of

vehicle as it moves in airways.

In future ,the advanced wireless pc control is

implemented to operate the vehicle with more precisely

accurate information .the speed of vehicle is to

increased more by using more efficient motors according

to that the design of quad copter should subject to

change.

55

APPENDICES

INTERFACING 8051 WITH ZIGBEE

INTERFACING 8051 WITH GPS

56

REFERENCES

1.AUVS– The Association of Unmanned VehicleSystems .

2.BEAR – The Berkeley Aerobot

Project.

http://robotics.eecs.berkel

ey.edu/bear/.

3.CMU – The Autonomous Helicopter Project .

http://www.cs.cmu.edu/afs/cs/project/chopper/www

/ heli project.html.

4.Computational Semantics Laboratory, Center for the

Study of Language and Information (CSLI) .

http://www-csli.stanford.edu/semlab/witas.html .

5.Scandi scraft Systems, Sweden.http://www.scandicraft.se /

6.The Hummingbird Project – Stanford

University . http://sun-valley.stanford.edu/users/heli/.

7.The NASA Deep Space I Project .http://ic.arc.nasa.gov/ic/autonomy.html .

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Research Facility.

http://controls.ae.gatech.edu/labs/uavrf

/.

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.

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Electronic Articles in Computer and Information

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