CHAPTER 1 Projek Poli Magin n Ganga

8/8/2019 CHAPTER 1 Projek Poli Magin n Ganga

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CHAPTER 1

INTRODUCTION TO PROJECT

1.1 Introduction

Our group has decided to do this project because it suitable with our course. We

use parallel port and electronic circuit to make this robot work properly.

This project will be controlled using pc that will moves the robot into different

directions. This will control by the Visual Basic.

1.2 Problem Statement

The problem statement for this project are;i. Normally, robots are control by remote control.

ii. Electronic component to build a robot are not easily can be find out.

iii. Robots are not easy to repair if occur problem except battery low.

1.3 Objective Of Project


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The objective of this project are;

i. To control the robot wirelessly.

ii. To make the robotic car move as we wish such as left, right, forward and reverse.

iii. To gain a knowledge in Visual Basic Programming. Learn to create command

button, insert the car picture and write the coding.

1.4 Scope

The scope for this project are;

i. This Wireless robot can move forward, reverse ,left and right and distance.

ii. Signal transmission can be 50meters (After tested ).

iii. Frequency for the signal transmission and receiver are 315 MHz.

iv. Control the robot by Visual Basic Programming.

1.5 Gannt Chart For Semester 5

The task we done when semester 5;

Table 1.1:Shows gannt chart for semester 5


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1.6 Gannt Chart For Semester 6

The task we done in semester 6;

Table 1.2:Shows gannt chart for semester 6

CHAPTER 2

LITERATURE REVIEW

2.1 Research About Background Of Project

The research for this project mainly about;

The rapid development in robots had given a deep impact to human life. The

research and development team have struggle a lot to invent a new technology. The

objective of inventing this mini robot is to control it by pc. Mini robot is used throughout

the world.

2.2 Differential


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The differential for this project are;

Our project is really different with others because this robot controlled from pc by

our self. This robotic car made wirelessly. Can reduce cable connection. Beside that, we

can move the robotic by pc to turn it left, right, forward and reverse.

CHAPTER 3

METHODOLOGY

3.1 Model Of Project

The sample model for this project;

Figure 3.1: Shows the model of project

3.2 Flow Chart For Project Perform

This flow chart explain about our project performent;

Find the title

StartFind the suitable


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circuit diagram

Study the circuit

Modify the

circuit

Write the proposal

Fixed the components on bread board

Testing the circuit

No

Yes

No

Yes

YesNo

Fixed the circuit on PCB board

Testing the circuit

Do the softwareDo the mechanical system

Test the project completely

NoYes

Etching and soldering

NoNoNo

End

Yes


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3.3 Block Diagram For Circuit Operation

The block diagram for this project mainly consist of;

COMPUTER (Visual Basic)

OUTPUT CIRCUIT(Interface between computer and output circuit)

TRANSMITTER

RECEIVER


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MOTOR

3.4 Circuit Diagram

The circuit diagram of wireless robotic car;

Figure 3.2: Shows schematic circuit for wireless robotic car


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3.4.1 Transmitter Circuit

This transmitter circuit for sending signal;

Figure 3.3: Shows schematic circuit for transmitter

3.4.2 Receiver Circuit

This receiver circuit to receive signal from transmitter;

Figure 3.4: Shows schematic circuit for receiver


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3.4.3 Motor Circuit

The motor circuit for wireless robotic car;

Figure 3.5: Shows schematic circuit for motor

3.5 Circuit Operation

The description of circuit operation is;

Circuit operation will be start from Visual basic programming which is main

controller for this project . Firstly, 5volt will supply by battery to the transmitter circuit.

Than, we can control our robotic car from visual basic programming by using parallel

port which connect to transmitter circuit. Later it will transmit the signal by antenna to

receiver circuit After that, IC 2804 will work as switch to operate the relays. Than the

relay will operate as switch when the inductor produce electromagnetic current.

Lastly, this signal send to motor to operate the car wheel as we need. For

example, a user press left button the parallel port will send the signal to input pin (IC

2262) and the output pin will send the signal to transmitter. The transmitter will send the

signal to receiver by antenna. After the receiver receive the signal, it will send the signal

to the input pin (IC 2272) and the output will send the signal to input pin (IC 74LS244)

and to the transistor. The output pin (IC 74LS244) will send the signal to IC 2804 which


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using as a buffer. The signal from the output pin (IC 2804) will send to relay which are

using as a switch for run the motor. After the motor was run and it make wheel move

left.

3.6 Flow Chart For The Combination Of Software And Hardware

The flow chart explain about combination of hardware and software for whole

project;

STARTTPress common button 1 or 2 or 3 or 4. For eg: press button 1 (forward)false

true

Button 1 change to green colour then forward car picture will appearThe data will send through parallel port pin 2 to transmitter (TX).

Antenna will send signal to RX and it will decode data.

Current flow through relay coil 1 and the motor 1 move the wheel 2 forward

Transmission must be valid or match with address setting.

END

3.7 Visual Basic Coding

Coding for make the motor circuit to operate;

Private Sub Command1_Click()


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If Command1.BackColor = &HFF& Then 'red

Image1.Visible = True 'image visible

Image2.Visible = False 'image no visibleImage3.Visible = False 'image no visible

Image4.Visible = False 'image no visible

Command1.BackColor = &HFF00& 'greenCommand2.BackColor = &HFF& 'red

Command3.BackColor = &HFF& 'red

Command4.BackColor = &HFF& 'redDlPortWritePortUchar 888, 10 '1010 (Forward)

'(1010=10)

Else

Command1.BackColor = &HFF& 'redDlPortWritePortUchar 888, 0 '0000 (Stop)




End IfEnd Sub


If Command2.BackColor = &HFF& Then 'redImage2.Visible = True 'image visible



Command2.BackColor = &HFF00& 'green

Command1.BackColor = &HFF& 'redCommand3.BackColor = &HFF& 'red


DlPortWritePortUchar 888, 5 '0101 (Back)'(0101=5)

Else


DlPortWritePortUchar 888, 0 '0000 (Stop)Image1.Visible = False 'image no visible



End If

End Sub





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Image4.Visible = False 'image no visibleCommand3.BackColor = &HFF00& 'green


Command2.BackColor = &HFF& 'redCommand4.BackColor = &HFF& 'red

DlPortWritePortUchar 888, 2 '0010 (Left)

'(0010=2)Else


DlPortWritePortUchar 888, 0 '0000 (Stop)




End IfEnd Sub






Command4.BackColor = &HFF00& 'greenCommand1.BackColor = &HFF& 'red


Command3.BackColor = &HFF& 'redDlPortWritePortUchar 888, 8 '1000 (Right)

'(1000=8)

ElseCommand4.BackColor = &HFF& 'red

DlPortWritePortUchar 888, 0 '0000 (Stop)




End IfEnd Sub

Private Sub Form_Load()




DlPortWritePortUchar 888, 0


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End Sub

3.8 Result For Visual Basic Coding

The display of Visual Basic coding consist of;

Figure 3.6: The view if user press up button in visual basic programming

Figure 3.7: The view if user press right button in visual basic programming

Figure 3.8: The view if user press down button in visual basic programming


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Figure 3.9: The view if user press left button in visual basic programming

3.9 List Of Component

The list of component we bought and prices for this project;

Quantity Item Price Amount (RM)

1 IC RECEIVER 315 23.00 23.00

1 IC TRANSMITTER 9906 18.40 18.40

1 IC 2272 6.40 6.40

1 IC 2262 6.00 6.00

2 BATTERY 9V 5.00 10.00

1 IC 2804 4.00 4.00

1 SET PCB 12.00 12.00

4 IC BASE 0.50 2.00

5 METER WIRE 0.50 2.50

13 LED 0.30 3.90

6 RESISTOR 0.10 0.60

1 74LS244 2.50 2.50

4 RELAY 2.50 10.00

TOTAL 101.30


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Table 3.3: Shows the list of component

CHAPTER 4

FINDING AND ANALYZING

4.1 Finding From The Circuit

We have faced some problems when making circuit .One of the major problem is

from the relay circuit . This is because we need to do the circuit repeatedly because it not

worked properly after connection been made . We made some correction from the

original circuit to make work properly.

4.2 COMPONENTS DESCRIPTIONS

In this project we are using many an electronic components, such as parallel port,

relay, transistor, IC 2804, twin gear motor and so on. Followings are the description for

all the component which are we using for this project.

4.2.1 Parallel Port

Parallel port is a simple and inexpensive tool for building computer controlled

devices and projects. The simplicity and ease of programming makes parallel port

popular in electronics hobbyist world. The parallel port is often used in Computer

controlled robots, Atmel/PIC programmers and home automation.


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Everybody knows what is parallel port, where it can be found, and for what it is

being used. the primary use of parallel port is to connect printers to computer and is

specifically designed for this purpose. Thus it is often called as printer Port or Centronics

port (this name came from a popular printer manufacturing company 'Centronics' who

devised some standards for parallel port). You can see the parallel port connector in the

rear panel of your PC. It is a 25 pin female (DB25) connector (to which printer is

connected).

Figure 4.1: Shows 25 pin parallel port (parallel printer port)

Table 4.1: Shows the parallel port signal lines

As you know, the Data, Control and status lines are connected to there corresponding

registers inside the computer. So by manipulating these registers in program , one can

easily read or write to parallel port with programming languages like 'C' and BASIC.

The registers found in standard parallel port are ;

1) data register

2) Status register

3) Control register

4.2.2 IC 2804 (Eight Darlington Arrays)

i. The ULN2804A each contain eight Darlington transistors with common emitters

and integral suppression diodes for inductive loads.

ii. ULN2804A has a 10.5kW input resistor for 6-15V CMOS.

iii. Supplied in a 18-lead plastic DIP with

iv. A copper lead from and feature the convenient input-opposite-output pin out to

simplify board layout.


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Figure 4.2: Shows IC 2804

4.2.3 Relay

A relay is an electrical switch that opens and closes under the control of another

electrical circuit. In the original form, the switch is operated by an electromagnet to open

or close one or many sets of contacts. It was invented by Joseph Henry in 1835. Because

a relay is able to control an output circuit of higher power than the input circuit, it can be

considered to be, in a broad sense, a form of an electrical amplifier.

Figure 4.3: Shows relay and symbol for relay

When a current flows through the coil, the resulting magnetic field attracts an

armature that is mechanically linked to a moving contact. The movement either makes or

breaks a connection with a fixed contact. When the current to the coil is switched off, the

armature is returned by a force approximately half as strong as the magnetic force to its

relaxed position. Usually this is a spring, but gravity is also used commonly in industrial

motor starters. Most relays are manufactured to operate quickly.

In a low voltage application, this is to reduce noise. In a high voltage or high current

application, this is to reduce arcing.

If the coil is energized with DC, a diode is frequently installed across the coil, to

dissipate the energy from the collapsing magnetic field at deactivation, which would

otherwise generate a spike of voltage and might cause damage to circuit components.

Some automotive relays already include that diode inside the relay case. Alternatively a

contact protection network, consisting of a capacitor and resistor in series, may absorb

the surge. If the coil is designed to be energized with AC, a small copper ring can be

crimped to the end of the solenoid. This "shading ring" creates a small out-of-phase

current, which increases the minimum pull on the armature during the AC cycle .
http://en.wikipedia.org/wiki/Switchhttp://en.wikipedia.org/wiki/Electrical_circuithttp://en.wikipedia.org/wiki/Magnethttp://en.wikipedia.org/wiki/Joseph_Henryhttp://en.wikipedia.org/wiki/1835http://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Current_(electricity)http://en.wikipedia.org/wiki/Coilhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Armature_(electrical_engineering)http://en.wikipedia.org/wiki/Spring_(device)http://en.wikipedia.org/wiki/Arcinghttp://en.wikipedia.org/wiki/Flyback_diodehttp://en.wikipedia.org/wiki/Switchhttp://en.wikipedia.org/wiki/Electrical_circuithttp://en.wikipedia.org/wiki/Magnethttp://en.wikipedia.org/wiki/Joseph_Henryhttp://en.wikipedia.org/wiki/1835http://en.wikipedia.org/wiki/Amplifierhttp://en.wikipedia.org/wiki/Current_(electricity)http://en.wikipedia.org/wiki/Coilhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Armature_(electrical_engineering)http://en.wikipedia.org/wiki/Spring_(device)http://en.wikipedia.org/wiki/Arcinghttp://en.wikipedia.org/wiki/Flyback_diode


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Relays are used for;

i. to control a high-voltage circuit with a low-voltage signal, as in some types of

modems,

ii. to control a high-current circuit with a low-current signal, as in the starter

solenoid of an automobile,

iii. to detect and isolate faults on transmission and distribution lines by opening and

closing circuit breakers (protection relays),

The relay's switch connections are usually labeled COM, NC and NO;

i. COM = Common, always connect to this, it is the moving part of the switch.

ii. NC = Normally Closed, COM is connected to this when the relay coil is off.

iii. NO = Normally Open, COM is connected to this when the relay coil is on.

iv. Connect to COM and NO if you want the switched circuit to be on when the

relay coil is on.

v. Connect to COM and NC if you want the switched circuit to be on when the

relay coil is off.

4.2.3.1 Usage of Relays And Transistors

Like relays, transistors can be used as an electrically operated switch. For

switching small DC currents (< 1A) at low voltage they are usually a better choice than a

relay. However transistors cannot switch AC or high voltages (such as mains electricity)

and they are not usually a good choice for switching large currents (> 5A). In these cases

a relay will be needed, but note that a low power transistor may still be needed to switch

the current for the relay's coil! The main advantages and disadvantages of relays are listed

below:

Advantages of relays are;

i. Relays can switch AC and DC, transistors can only switch DC.

ii. Relays can switch high voltages, transistors cannot.

iii. Relays are a better choice for switching large currents (> 5A).
http://en.wikipedia.org/wiki/Modemhttp://en.wikipedia.org/wiki/Current_(electricity)http://en.wikipedia.org/wiki/Starter_motorhttp://en.wikipedia.org/wiki/Solenoidhttp://en.wikipedia.org/wiki/Automobilehttp://en.wikipedia.org/wiki/Circuit_breakershttp://www.kpsec.freeuk.com/components/tran.htmhttp://en.wikipedia.org/wiki/Modemhttp://en.wikipedia.org/wiki/Current_(electricity)http://en.wikipedia.org/wiki/Starter_motorhttp://en.wikipedia.org/wiki/Solenoidhttp://en.wikipedia.org/wiki/Automobilehttp://en.wikipedia.org/wiki/Circuit_breakershttp://www.kpsec.freeuk.com/components/tran.htm


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iv. Relays can switch many contacts at once.

Disadvantages of relays are;

i. Relays are bulkier than transistors for switching small currents.

ii. Relays cannot switch rapidly (except reed relays), transistors can switch many

times per second.

iii. Relays use more power due to the current flowing through their coil.

iv. Relays require more current than many ICs can provide, so a low power

transistor may be needed to switch the current for the relay's coil.

You need to consider several features when choosing a relay;

1. Physical size and pin arrangement

If you are choosing a relay for an existing PCB you will need to ensure that its

dimensions and pin arrangement are suitable. You should find this information in

the supplier's catalogue.

2. Coil voltage

The relay's coil voltage rating and resistance must suit the circuit powering the

relay coil. Many relays have a coil rated for a 12V supply but 5V and 24V relays

are also readily available. Some relays operate perfectly well with a supply

voltage which is a little lower than their rated value.

3. Coil resistance

The circuit must be able to supply the current required by the relay coil. You can

use Ohm's law to calculate the current:

Relay coil current =supply voltage

coil resistance

4. For example: A 12V supply relay with a coil resistance of 400 passes a current of

30mA. This is OK for a 555 timer IC (maximum output current 200mA), but it is

too much for most ICs and they will require a transistorto amplify the current.

5. Switch ratings (voltage and current)

The relay's switch contacts must be suitable for the circuit they are to control. You

will need to check the voltage and current ratings. Note that the voltage rating is

usually higher for AC, for example: "5A at 24V DC or 125V AC".
http://www.kpsec.freeuk.com/ohmslaw.htmhttp://www.kpsec.freeuk.com/trancirc.htm#ichttp://www.kpsec.freeuk.com/ohmslaw.htmhttp://www.kpsec.freeuk.com/trancirc.htm#ic


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4.2.4 Light Emitting Diode (LED)

A light-emitting diode, usually called an LED is a semiconductordiode that emits

incoherent narrow-spectrum light when electricallybiased in the forward direction of the

p-n junction, as in the common LED circuit. This effect is a form ofelectroluminescence.

An LED is usually a small area light source, often with optics added to the chip to

shape its radiation pattern . LEDs are often used as small indicator lights on electronic

devices and increasingly in higher power applications such as flashlights and area

lighting. The colorof the emitted light depends on the composition and condition of the

semiconducting material used, and can be infrared, visible, orultraviolet. LEDs can also

be used as a regular household light source. Besides lighting, interesting applications

include sterilization of water and disinfection of devices .

Figure 4.4: Shows the type and polarity of resister

Like a normal diode, the LED consists of a chip of semiconducting material

impregnated, or doped, with impurities to create a p-n junction. As in other diodes,

current flows easily from the p-side, or anode, to the n-side, or cathode, but not in the

reverse direction.

The wavelength of the light emitted, and therefore its color, depends on the band

gap energy of the materials forming the p-n junction. In silicon orgermanium diodes, the

electrons and holes recombine by a non-radiative transition which produces no optical

emission, because these are indirect band gap materials. The materials used for the LED
http://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Coherence_(physics)http://en.wikipedia.org/wiki/Lighthttp://en.wikipedia.org/wiki/Voltage_biashttp://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/LED_circuithttp://en.wikipedia.org/wiki/Electroluminescencehttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Visible_spectrumhttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Doping_(semiconductor)http://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/Anodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Band_gaphttp://en.wikipedia.org/wiki/Band_gaphttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Germaniumhttp://en.wikipedia.org/wiki/Indirect_band_gaphttp://en.wikipedia.org/wiki/Semiconductorhttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Coherence_(physics)http://en.wikipedia.org/wiki/Lighthttp://en.wikipedia.org/wiki/Voltage_biashttp://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/LED_circuithttp://en.wikipedia.org/wiki/Electroluminescencehttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Visible_spectrumhttp://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Diodehttp://en.wikipedia.org/wiki/Doping_(semiconductor)http://en.wikipedia.org/wiki/P-n_junctionhttp://en.wikipedia.org/wiki/Anodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Band_gaphttp://en.wikipedia.org/wiki/Band_gaphttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Germaniumhttp://en.wikipedia.org/wiki/Indirect_band_gap


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have a direct band gap with energies corresponding to near-infrared, visible or near-

ultraviolet light.

LED development began with infrared and red devices made with gallium

arsenide. Advances in materials science have made possible the production of devices

with ever-shorterwavelengths, producing light in a variety of colors.

LEDs are usually built on an n-type substrate, with an electrode attached to the p-

type layer deposited on its surface. P-type substrates, while less common, occur as well.

Many commercial LEDs, especially GaN/InGaN, also use sapphire substrate. Substrates

that are transparent to the emitted wavelength, and backed by a reflective layer, and light

spreading layer, increase the LED efficiency. The refractive index of the package

material should match the index of the semiconductor, otherwise the produced light gets

partially reflected back into the semiconductor, where it may be absorbed and turned into

additional heat, thus lowering the efficiency. This type of reflection also occurs at the

surface of the package if the LED is coupled to a medium with a different refractive

index such as a glass fiber or air.

The refractive index of most LED semiconductors is quite high, so in almost all

cases the LED is coupled into a much lower-index medium. The large index difference

makes the reflection quite substantial (per the Fresnel coefficients), and this is usually

one of the dominant causes of LED inefficiency. Often more than half of the emitted light

is reflected back at the LED-package and package-air interfaces. The reflection is most

commonly reduced by using a dome-shaped (half-sphere) package with the diode in the

center so that the outgoing light rays strike the surface perpendicularly, at which angle

the reflection is minimized.

An anti-reflection coating may be added as well. The package may be cheap

plastic, which may be colored, but this is only for cosmetic reasons or to improve the

contrast ratio; the color of the packaging does not substantially affect the color of the

light emitted. Other strategies for reducing the impact of the interface reflections include

designing the LED to reabsorb and reemit the reflected light (called photon recycling)

and manipulating the microscopic structure of the surface to reduce the reflectance, either

by introducing random roughness or by creating programmed moth eye surface patterns.

Figure 4.5: Shows the type of LED
http://en.wikipedia.org/wiki/Direct_band_gaphttp://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Materials_sciencehttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Sapphirehttp://en.wikipedia.org/wiki/Refractive_indexhttp://en.wikipedia.org/wiki/Fresnel_equationshttp://en.wikipedia.org/wiki/Anti-reflection_coatinghttp://en.wikipedia.org/wiki/Direct_band_gaphttp://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Gallium_arsenidehttp://en.wikipedia.org/wiki/Materials_sciencehttp://en.wikipedia.org/wiki/Wavelengthhttp://en.wikipedia.org/wiki/Sapphirehttp://en.wikipedia.org/wiki/Refractive_indexhttp://en.wikipedia.org/wiki/Fresnel_equationshttp://en.wikipedia.org/wiki/Anti-reflection_coating


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Conventional LEDs are made from a variety of inorganic semiconductor materials,

producing the following colors:

i. Aluminium gallium arsenide (AlGaAs) red and infrared

ii. Aluminium gallium phosphide (AlGaP) green

iii. Aluminium gallium indium phosphide (AlGaInP) high-brightness orange-red,

orange, yellow, and green

iv. Gallium arsenide phosphide (GaAsP) red, orange-red, orange, and yellow

v. Gallium phosphide (GaP) red, yellow and green

vi. Gallium nitride (GaN) green, pure green (or emerald green), and blue also

white (if it has an AlGaN Quantum Barrier)

vii. Indium gallium nitride (InGaN) 450470 nm near ultraviolet, bluish-green

and blue

viii. Silicon carbide (SiC) as substrate blue

ix. Silicon (Si) as substrate blue (under development)

x. Sapphire (Al2O3) as substrate blue

xi. Zinc selenide (ZnSe) blue

xii. Diamond (C) ultraviolet

xiii. Aluminium nitride (AlN), aluminium gallium nitride (AlGaN), aluminium

gallium indium nitride (AlGaInN) near to farultraviolet (down to 210 nm .

4.2.4.1 White LEDs

A combination of red, green and blue LEDs can produce the impression of white

light, though white LEDs today rarely use this principle. Most white LEDs in

production are modified blue LEDs: GaN-based, InGaN-active-layer LEDs emit blue

light of wavelengths between 450 nm and 470 nm. This InGaN-GaN structure is covered
http://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Aluminium_gallium_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Orange_(color)http://en.wikipedia.org/wiki/Yellowhttp://en.wikipedia.org/wiki/Gallium_phosphidehttp://en.wikipedia.org/wiki/Gallium_nitridehttp://en.wikipedia.org/wiki/Bluehttp://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Silicon_carbidehttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Sapphirehttp://en.wikipedia.org/wiki/Zinc_selenidehttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Aluminium_nitridehttp://en.wikipedia.org/wiki/Aluminium_gallium_nitridehttp://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/Whitehttp://en.wikipedia.org/wiki/Semiconductor_materialshttp://en.wikipedia.org/wiki/Aluminium_gallium_arsenidehttp://en.wikipedia.org/wiki/Infraredhttp://en.wikipedia.org/wiki/Aluminium_gallium_phosphidehttp://en.wikipedia.org/wiki/Aluminium_gallium_indium_phosphidehttp://en.wikipedia.org/wiki/Gallium_arsenide_phosphidehttp://en.wikipedia.org/wiki/Orange_(color)http://en.wikipedia.org/wiki/Yellowhttp://en.wikipedia.org/wiki/Gallium_phosphidehttp://en.wikipedia.org/wiki/Gallium_nitridehttp://en.wikipedia.org/wiki/Bluehttp://en.wikipedia.org/wiki/Indium_gallium_nitridehttp://en.wikipedia.org/wiki/Silicon_carbidehttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Sapphirehttp://en.wikipedia.org/wiki/Zinc_selenidehttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Aluminium_nitridehttp://en.wikipedia.org/wiki/Aluminium_gallium_nitridehttp://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Aluminium_gallium_indium_nitride&action=edit&redlink=1http://en.wikipedia.org/wiki/Ultraviolethttp://en.wikipedia.org/wiki/White


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with a yellowish phosphor coating usually made of cerium-doped yttrium aluminum

garnet (Ce3+:YAG) crystals which have been powdered and bound in a type of viscous

adhesive. The LED chip emits blue light, part of which is efficiently converted to a broad

spectrum centered at about 580 nm (yellow) by the Ce3+:YAG. Since yellow light

stimulates the red and green receptors of the eye, the resulting mix of blue and yellow

light gives the appearance of white, the resulting shade often called lunar white. This

approach was developed by Nichia Corporation and has been used since 1996 for the

manufacture of white LEDs.

Figure 4.6: Shows the white LED and the symbol

The pale yellow emission of the Ce3+:YAG can be tuned by substituting the

cerium with other rare earth elements such as terbium and gadolinium and can even be

further adjusted by substituting some or all of the aluminum in the YAG with gallium.

Due to the spectral characteristics of the diode, the red and green colors of objects in its

blue yellow light are not as vivid as in broad-spectrum light.

Manufacturing variations and varying thicknesses in the phosphor make the LEDs

produce light with different color temperatures, from warm yellowish to cold bluish; the

LEDs have to be sorted during manufacture by their actual characteristics. Philips

Lumileds patented conformal coating process addresses the issue of varying phosphor

thickness, giving the white LEDs a more consistent spectrum of white light.

White LEDs can also be made by coating near ultraviolet (NUV) emitting LEDs

with a mixture of high efficiency europium-based red and blue emitting phosphors plus

green emitting copper and aluminum doped zinc sulfide (ZnS:Cu, Al). This is a method

analogous to the way fluorescent lamps work. However the ultraviolet light causes

photodegradation to the epoxy resin and many other materials used in LED packaging,

causing manufacturing challenges and shorter lifetimes.

This method is less efficient than the blue LED with YAG:Ce phosphor, as the

Stokes shift is larger and more energy is therefore converted to heat, but yields light with

better spectral characteristics, which render color better. Due to the higher radiative
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output of the ultraviolet LEDs than of the blue ones, both approaches offer comparable

brightness .

The newest method used to produce white light LEDs uses no phosphors at all

and is based on homoepitaxially grown zinc selenide (ZnSe) on a ZnSe substrate which

simultaneously emits blue light from its active region and yellow light from the substrate

A new technique developed by Michael Bowers, a graduate student at Vanderbilt

University in Nashville, involves coating a blue LED with quantum dots that glow white

in response to the blue light from the LED. This technique produces a warm, yellowish-

white light similar to that produced by incandescent bulbs .

The advantages of using LEDs are;

i. LEDs produce more light per watt than incandescent bulbs; this is useful in

battery powered or energy-saving devices.

ii. LEDs can emit light of an intended color without the use of color filters that

traditional lighting methods require. This is more efficient and can lower initial

costs.

iii. The solid package of the LED can be designed to focus its light. Incandescent and

fluorescent sources often require an external reflector to collect light and direct it

in a usable manner.

iv. When used in applications where dimming is required, LEDs do not change their

color tint as the current passing through them is lowered, unlike incandescent

lamps, which turn yellow.

v. LEDs are ideal for use in applications that are subject to frequent on-off cycling,

unlike fluorescent lamps that burn out more quickly when cycled frequently, or

HID lamps that require a long time before restarting.

vi. LEDs, being solid state components, are difficult to damage with external shock.

Fluorescent and incandescent bulbs are easily broken if dropped on the ground.

vii. LEDs can have a relatively long useful life. One report estimates 35,000 to 50,000

hours of useful life, though time to complete failure may be longer. Fluorescent
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tubes typically are rated at about 30,000 hours, and incandescent light bulbs at

1,0002,000 hours .

viii. LEDs mostly fail by dimming over time, rather than the abrupt burn-out of

incandescent bulbs .

Figure 4.7: Shows polarity and symbol for LED

4.2.4.2 LEDs Indicator

Miniature LEDs indicator are normally driven from low voltage DC via a current

limiting resistor. Currents of 2 mA, 10 mA and 20 mA are common. Some low current

indicators are only rated to 2 mA, and should not be driven at higher current.

Sub-mA indicators may be made by driving ultrabright LEDs at very low current.

Efficacy tends to reduce at low currents, but indicators running on 100 A are still

practical. The cost of ultrabrights is higher than 2 mA indicator LEDs.

LEDs have a low max repeat reverse voltage rating, ranging from approximately

2 V to 5 V, and this can be a problem in some applications. Back to back LEDs are

immune to this problem. These are available in single color as well as bicolor types.

There are various strategies for reverse voltage handling.
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4.2.5 Voltage Regulator

The Digilab board can use any power supply that creates a DC voltage between 6

and 12 volts. A 5V voltage regulator (7805) is used to ensure that no more than 5V is

delivered to the Digilab board regardless of the voltage present at the J12 connector

(provided that voltage is less than 12VDC). The regulator functions by using a diode to

clamp the output voltage at 5VDC regardless of the input voltage - excess voltage is

converted to heat and dissipated through the body of the regulator. If a DC supply of

greater than 12V is used, excessive heat will be generated, and the board may be

damaged. If a DC supply of less than 5V is used, insufficient voltage will be present at

the regulators output.

Figure 4.8: Shows positive voltage regulator

If a power supply provides a voltage higher than 7 or 8 volts, the regulator must

dissipate significant heat. The "fin" on the regulator body (the side that protrudes upward

beyond the main body of the part) helps to dissipate excess heat more efficiently. If the

board requires higher currents (due to the use of peripheral devices or larger breadboard

circuits), then the regulator may need to dissipate more heat. In this case, the regulator

can be secured to the circuit board by fastening it with a screw and nut (see below).

4.2.6Transistor

In electronics, a transistor is a semiconductor device commonly used to amplify

or switch electronic signals. The transistor is the fundamental building block of

computers, and all other modern electronic devices. Some transistors are packaged

individually but most are found in integrated circuits.

An electrical signal can be amplified by using a device that allows a small current

or voltage to control the flow of a much larger current. Transistors are the basic devices
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providing control of this kind. Modern transistors are divided into two main categories:

bipolar junction transistors (BJTs) and field effect transistors (FETs). Applying current in

BJTs and voltage in FETs between the input and common terminals increases the

conductivity between the common and output terminals, thereby controlling current flow

between them. The characteristics of a transistor depend on its type.

Figure 4.9: Shows types of transistor

The term "transistor" originally referred to thepoint contact type, which saw very

limited commercial application, being replaced by the much more practical bipolar

junction types in the early 1950s. Today's most widely used schematic symbol, like the

term "transistor", originally referred to these long-obsolete devices .

In analog circuits, transistors are used in amplifiers, (direct current amplifiers,

audio amplifiers, radio frequency amplifiers), and linear regulated power supplies.

Transistors are also used in digital circuits where they function as electronic switches, but

rarely as discrete devices, almost always being incorporated in monolithic Integrated

Circuits. Digital circuits include logic gates, random access memory (RAM),

microprocessors, and digital signal processors (DSPs).

The key advantages that have allowed transistors to replace their vacuum tube

predecessors in most applications are:

i. Small size and minimal weight, allowing the development of miniaturized

electronic devices.

ii. Highly automated manufacturing processes, resulting in low per-unit cost.

iii. Lower possible operating voltages, making transistors suitable for small, battery-

powered applications.

iv. No warm-up period for cathode heaters required after power application.

v. Lower power dissipation and generally greater energy efficiency.

vi. Higher reliability and greater physical ruggedness.

vii. Extremely long life. Some transistorized devices produced more than 30 years ago

are still in service.
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viii. Complementary devices available, facilitating the design of complementary-

symmetry circuits, something not possible with vacuum tubes.

ix. Though in most transistors the junctions have different doping levels and

geometry, some allow bidirectional current

x. Ability to control very large currents, as much as several hundred amperes.

xi. Insensitivity to mechanical shock and vibration, thus avoiding the problem of

microphonics in audio applications.

xii. More sensitive than the hot and macroscopic tubes

The usage of transistor are;

In the early days of transistor circuit design, the bipolar junction transistor, or

BJT, was the most commonly used transistor. Even after MOSFETs became available,the BJT remained the transistor of choice for digital and analog circuits because of their

ease of manufacture and speed. However, desirable properties of MOSFETs, such as their

utility in low-power devices, have made them the ubiquitous choice for use in digital

circuits and a very common choice for use in analog circuits.

i) Switches

Transistors are commonly used as electronic switches, for both high powerapplications including switched-mode power supplies and low power applications such as

logic gates.

ii) Amplifiers

From mobile phones to televisions, vast numbers of products include amplifiers

for sound reproduction, radio transmission, and signal processing. The first discrete

transistor audio amplifiers barely supplied a few hundred milliwatts, but power and audio
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fidelity gradually increased as better transistors became available and amplifier

architecture evolved.

Transistors are commonly used in modern musical instrument amplifiers, in

which circuits up to a few hundred watts are common and relatively cheap. Transistors

have largely replaced valves (electron tubes) in instrument amplifiers. Some musical

instrument amplifier manufacturers mix transistors and vacuum tubes in the same circuit,

to utilize the inherent benefits of both devices.

4.2.7 ResistorA resistor is a two-terminal electrical or electronic component that opposes an

electric current by producing a voltage drop between its terminals in proportion to the

current, that is, in accordance with Ohm's law: V = IR. The electrical resistance R is

equal to the voltage drop V across the resistor divided by the current I through the

resistor. Resistors are used as part ofelectrical networks and electronic circuits .

Figure 4.10: Shows types of resistor

Most axial resistors use a pattern of colored stripes to indicate resistance. Surface-

mount resistors are marked numerically. Cases are usually brown, blue, or green, though

other colors are occasionally found such as dark red or dark grey. One can also use a

multimeterorohmmeterto test the values of a resistor.

Four-band identification is the most commonly used color coding scheme on all

resistors. It consists of four colored bands that are painted around the body of the resistor.
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The scheme is simple: The first two numbers are the first two significant digits of the

resistance value, the third is a multiplier, and the fourth is the tolerance of the value (e.g.

green-blue-yellow red : 56 x (10^4) ohms = 56 x 10000 ohms = 560 Kohms 2%). Each

color corresponds to a certain number, shown in the chart below. The tolerance for a 4-

band resistor will be 1%, 5%, or 10%.

Color 1st band 2nd band 3rd band (multiplier) 4th band (tolerance) Temp. Coefficient

Black 0 0 100

Brown 1 1 101 1% (F) 100 ppm

Red 2 2 102 2% (G) 50 ppm

Orange 3 3 103 15 ppm

Yellow 4 4 104 25 ppm

Green 5 5 105 0.5% (D)

Blue 6 6 106 0.25% (C)

Violet 7 7 107 0.1% (B)Gray 8 8 108 0.05% (A)

White 9 9 109

Gold 10-1 5% (J)

Silver 10-2 10% (K)

None 20% (M)

Table 4.2:Shows the Reading resistance values

4.2.8 Twin Motor Gear Box

The Twin Motor Gear Box uses a two motor system to provide power and speed

to turn the hex shaft. The gear box is made from high quality plastic. Use this gear box

and motor set with other Tamiya Construction and Robotics products. Provides full

forward, reverse, left and right action.

Figure 4.11: Shows the Twin Motor Gear Box


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CHAPTER 5

CONCLUSION

5.1 Conclusion

Firstly, this is not a simple task to do but by doing this project we learned

something new skills and knowledge. We are putting a high effort for this project so that

it can be successful and useful product to everyone.

We learned so much fruitful knowledge and skills at the ending of this project. We

really get knew about the a project ingredients such as PCB layout, etching, soldering,

and software.

In additional, we also faced a lot of obstacles such as the PCB layout was wrongly

designed, led not light up, the signal cannot transmitted, did know the correct method of

soldering, and so on.

Now days, a lot of work done by robot. This robot are build for a general purpose. It

can be upgrade by connect mini camera and use it as a CCTV, to help people to vacuum

automatically and so on. This robot can move left, right, forward and reverse.

Finally, we would like to say thanks to our beloved lecturers and friends.


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APPENDIX

PCB Design

The PCB layout for motor circuit by using marker pen

After finish the drawing

The PCB layout by using software PCB WIZARD

Picture Of Circuit

Transmitter Circuit with parallel port


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Receiver circuit

Motor circuit

Twin gear motor with the wheel

This is our wireless robotic car

Nama E-mel baru untuk anda!

Dapatkan nama E-mel yang telah lama anda mahukan pada @ymail dan @rocketmail

yang baru.Cepat sebelum orang lain mendapatkannya!
http://sg.rd.yahoo.com/my/mail/domainchoice/mail/signature/*http:/mail.promotions.yahoo.com/newdomains/my/http://sg.rd.yahoo.com/my/mail/domainchoice/mail/signature/*http:/mail.promotions.yahoo.com/newdomains/my/

CHAPTER 1 Projek Poli Magin n Ganga

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