A

MINOR PROJECT-III

REPORT

ON

HIGHWAY ALERT SIGNAL LAMP

SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE

AWARD OF THE DEGREEE OF

BACHELOR OF TECHNOLOGY

Session-2010-2011

SUBMITTED TO:- SUBMITTED BY:-

Mr. LOKESH FARHANA PERWEEN

LECTURER BRANCH E&C(5th SEM)

ELECTRONICS & COMM. DEP’T ROLL NO-5EC 28

ELECTRONICS & COMMUNICATION DEPARTMENT

JAIPUR NATIONAL UNIVERSITY

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ACKNOWLEDGEMENTWith profound respect and gratitude I take the opportunity to express my sincere thanks

to PROFF. LAKSHMI NARAYAN (H.O.D Of ELECTRONICS &

COMMUNICATION) for providing me support to complete my project on

“HIGHWAY ALERT SIGNAL LAMP”.

We here especially thankful to all my teachers & lecturers ,colleagues, friends and well-

wishers who have always a good word for me, including a source of strength for taking

this venture.

During the course of preparation of this project , we had the advantage of generous help

of many but in particular, we wish to acknowledge with thanks the inspiration and

encouragement provided by our professor, MR LOKESH without which this project

work would not have seen the light of the day.

FARHANA PERWEEN 5EC-28

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CERTIFICATE

This is to certify that the project titled “HIGHWAY ALERT SIGNAL LAMP” submitted

by FARHANA PERWEEN, B.Tech-5th (Electronics & Communication) is student’s own

work carried out my supervision and guidance. The matter embodied in this report is

original in character and has not been submitted under any other project.

Head of department

Electronics and communication

Jaipur national university

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ABSTRACT

The project that we have done here can be used for safe highway driving. The lamp

automatically emits brilliant tri-colourlight when a vehicle approaches the rear side of the

vehicle. And turns off when the approaching vehicle overtakes.

This Ultra-bright blue yellow and redheads of the signal alert lamp emits very bright light

to alert vehicle's driver even during daytime, giving additional safety during night or

when we need to stop our vehicle on the side of the highway. The circuit saves

considerable battery power. 12v DC supple to the circuit can be provided by the car

battery with proper polarity.

High way alert signal lamp is used in vehicles for safe highway driving. The lamp

automatically emits the brilliant tricolour light when a vehicle approaches the rear side of

the vehicle and alerts the driver by this indication about the approach of the vehicle from

behind.l2v DC supply to the Circuit can be provided by car battery with proper polarity.

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TOPIC OF CONTENTS

TOPIC PAGE NO.

Introduction…………………………………………7

Components Used….……………………………….8

Circuit Diagram……………………………………..9

Working Principle…………………………………..10

Study Of Component………………………………..11-18

555 Timer

Transistors (BC548, BC558,L14F1)

Resistors

Capacitor

LEDs

Battery

PCB

Apendix…………………………………………………19

Conclusion………………………………………………20

Reference………………………………………………..21

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A

PROJECT REPORT

ON

HIGHWAY ALERT SIGNAL LAMP

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1. INTRODUCTION

The lighting system of a motor vehicle consists of lighting and signalling devices

mounted or integrated to the front, sides, rear, and in some cases the top of the vehicle.

The purpose of this system is to provide illumination for the driver to operate the vehicle

safely after dark, to increase the conspicuity of the vehicle, and to display information

about the vehicle's presence, position, size, direction of travel, and driver's intentions

regarding direction and speed of travel. Driving lamp" is a term deriving from the early

days of night time driving, when it was relatively rare to encounter an opposing vehicle.

Only on those occasions when opposing drivers passed each other would the dipped or

"passing" beam be used. The full beam was therefore known as the driving beam. Turn

signals are required to blink on and off, or "flash", at a steady rate of between 60 and 120

blinks per minute (Although some operate slower than this). International regulations

require that all turn signals activated at the same time (i.e., all right signals or all left

signals) flash in simultaneous phase with one another; North American regulations also

require simultaneous operation, but permit side markers wired for side turn signal

functionality to flash in opposite-phase. Worldwide regulations stipulate an

audiovisual telltale when the turn signals are activated; this usually takes the form of one

combined or separate left and right green indicator lights on the vehicle's instrument

cluster, and a cyclical "tick-tock" noise generated electromechanically or electronically. It

is also required that audio and/or visual warning be provided to the vehicle operator in

the event of a turn signal's failure to light. This warning is usually provided by a much

faster- or slower-than-normal flash rate, visible on the dashboard indicator, and audible

via the faster tick-tock sound.

Turn signals are in almost every case activated by means of a horizontal lever (or "stalk")

protruding from the side of the steering column, though some vehicles have the lever

mounted instead to the dashboard. The outboard end of the stalk is pushed clockwise to

activate the right turn signals, or anticlockwise for the left turn signals. This operation is

intuitive; for any given steering manoeuvre, the stalk is pivoted in the same direction as

the ateering wheel must be turned.

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2. COMPONENTS USED

R1 = 8.2k

R2 = 4.7k

R3 = 10k

R4 = 100

R5 = 470

R6 = 22k

R7 = 33k

IC 555

Capacitor

Darlington Phototransistor (L14F1)

Transistor

LEDs

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3. CIRCUIT DIAGRAM

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WORKING PRINCIPLE

This is the signal lamp for safe highway driving. The lamp automatically emits brilliant

tricolour light when a vehicle approaches the rear side of your vehicle. It emits light for

30 seconds that turns off when the approaching vehicle overtakes. The ultra-bright blue,

white and red LEDs of the signal lamp emit very bright light to alert the approaching

vehicle’s driver even during the day, giving additional safety during night or when you

need to stop your vehicle on side of the highway. The circuit saves considerable battery

power.

The circuit is built around two timer ICs NE555(IC1& IC2). IC1 is designed as a

standard monostable, while IC2 is designed as an astable. Darlington Phototransistor

L14F1 (T1) is used as a photosensor to activate the monostable. The collector of

Phototransistor T1 is connected to trigger pin 2 of IC1, which is normally kept high by

resistor R1. When headlight from an approaching vehicle illuminates the phototransistor,

it conducts to give a short pulse to IC1, and the output of IC1 goes high for a 4 period

determined by resistor R2 and capacitor C1. The output of IC1 is fed to the base of

transistor T2 via resistor R3. Transistor T2 conducts to drive transistor T3 and its

collector goes high to take reset pin 4 of IC2to high level. This activates astable IC2,

which switches on and off the LED chain alternately. The intermittent flashing of LEDs

gives a beautiful tricolour flashing effect. 12 volt DC supply to the circuit, can be

provided by your vehicle battery with proper polarity.

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4. Components Used

555 IC

The 555 IC is available as an 8-pin metal can, an 8-pin mini DIP(dual in package) or a

14-pin DIP. This IC consists of 23 transistors, 2 diodes and 16 resistors.

Pin 1(Grounded Terminal):- All the voltages are measured w.r.t this terminal.

Pin 2(Trigger Terminal):- This pin is an inverting input to a comparator that is responsible

for transition of flip-flop from set to reset.

Pin 3(Output Terminal):- Output of the timer is available at this pin.

Pin4(Reset Terminal):- To disable or reset the timer a negative pulse is applied to this pin

due to which it is referred to reset terminal.

Pin 5(Control Voltage Terminal):- The function of this terminal is to control the threshold

and trigger levels.

Pin 6(Threshold Terminal):- This is the non-inverting input terminal of comparator1,

which compares the voltage applied to this terminal with a reference voltage of +2/3 Vcc.

Pin 7(Discharge Terminal):- This pin is connected internally to the collector of transistor

and mostly a capacitor is connected between this terminal and ground.

Pin 8(Supply Terminal):- A supply voltage of +5V to +18V is applied to this terminal

w.r.t ground.

.

Fig. 2: IC555

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Monostable mode

Monostable multivibrator often called a one shot multivibrator is a pulse generating

circuit in which the duration of this pulse is determined by the RC network connected

externally to the 555 timer. In a stable or standby state, the output of the circuit is

approximately zero or a logic-low level. When external trigger pulse is applied output is

forced to go high (» VCC). The time for which output remains high is determined by the

external RC network connected to the timer. At the end of the timing interval, the output

automatically reverts back to its logic-low stable state. The output stays low until trigger

pulse is again applied. Then the cycle repeats. The monostable circuit has only one stable

state (output low) hence the name monostable.

Fig.3: Circuit Diagram of Monostable Multivibrator

Waveform

Fig.4: Output Waveform of IC555 in Monostable Mode

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Astable mode

The astable multivibrator generates a square wave, the period of which is determined by

the circuit external to IC 555. The astable multivibrator does not require any external

trigger to change the state of the  output. Hence the name free running oscillator. The

time during which the output is either high or low is determined by the two resistors and

a capacitor which are externally connected to the 555 timer. The figure shows the 555

timer connected as an astable multivibrator. Initially when the output is high capacitor C

starts charging towards  Vcc through RA and RB.

Fig.5: Circuit Diagram of 555 timer in Astable Mode

Waveform

Fig.6: Output waveform of 555 timer in Astable Mode

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Transistor

A transistor is a semiconductor device used to amplify and switch electronic signals. It is

made of a solid piece of semiconductor material, with at least three terminals for

connection to an external circuit. A voltage or current applied to one pair of the

transistor's terminals changes the current flowing through another pair of terminals.

Because the controlled (output) power can be much more than the controlling (input)

power, the transistor provides amplification of a signal. Some transistors are packaged

individually but many more are found embedded in integrated circuits.The transistor is

the fundamental building block of modern electronic devices, and its presence is

ubiquitous in modern electronic systems.

Fig.7: Transistor

RESISTOR

A resistor is a two-terminal electronic component that produces a voltage across its

terminals that is proportional to the electric current through it in accordance with Ohm's

law

V = IR

Resistors are elements of electrical networks and electronic circuits and are ubiquitous in

most electronic equipment.

Fig.8: Resistor

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Capacitor

A capacitor is a passive electronic component consisting of a pair of conductors separated

by a dielectric. When a voltage potential difference exists between the conductors, an

electric field is present in the dielectric. This field stores energy and produces a

mechanical force between the plates. An ideal capacitor is characterized by a single

constant value, capacitance, which is measured in farads. This is the ratio of the electric

charge on each conductor to the potential difference between them. In practice the

dielectric between the plates passes a small amount of leakage current. The conductors

and leads introduce an equivalent series resistance and the dielectric has an electric field

strength limit resulting in a breakdown voltage.

They are widely used in electronic circuit to block the flow of direct current while

allowing alternating current to pass, to filter out interferance, to smooth the output of

power supplies, and for many other purposes. They are used in radio frequency

equipment to select particular frequencies from a signal with many frequencies.

fig.9:Capacitor

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LED

A light-emitting diode (LED) is a semiconductor light source. LEDs are used as

indicator lamps in many devices, and are increasingly used for lighting. Introduced as a

practical electronic component in 1962, early LEDs emitted low-intensity red light, but

modern versions are available across the visible, ultraviolet and infrared wavelengths,

with very high brightness.When a light-emitting diode is forward biased (switched

on), electrons are able to recombine with holes within the device, releasing energy in the

form of photons. This effect is called electroluminescence and the colour of the light

(corresponding to the energy of the photon) is determined by the  energy gap of the

semiconductor. An LED is often small in area (less than 1 mm2), and integrated optical

components may be used to shape its radiation pattern. LEDs present

many advantages over incandescent light sources including lower energy consumption,

longer lifetime, improved robustness, smaller size, faster switching, and greater durability

and reliability

Fig.10: LEDs

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Battery

The battery cells create a voltage difference between the terminals of each cell and

hence to its combination in battery.

When an external circuit is connected to the battery, then the battery drives electrons

through the circuit and electrical work is done. The battery has become a common power

source for many household and industrial applications, and is now a multi-billion dollar

industry.

Fig.11: Battery

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PHOTOTRANSISTOR

Phototransistor is Like diodes, all transistors are light-sensitive. Phototransistors are

designed specifically to take advantage of this fact. The most-common variant is an NPN

bipolar transistor with an exposed base region. Here, light striking the base replaces what

would ordinarily be voltage applied to the base. So, a phototransistor amplifies variations

in the light striking it. Note that phototransistors may or may not have a base lead (if they

do, the base lead allows you to bias the phototransistor’s light response. Here we use

Darlington Phototransistor (L14F1) as a photosensor to activate the monostable IC1. The

collector of phototransistor T1 is connected to trigger pin2 of IC1, which is normally kept

high by resistor R1.When headlight from an approaching vehicle illuminates the

phototransistor. It conduct to give a short pulse to IC1.

Fig.12: Darlington Phototransistor

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CONCLUSION

In this project I have learned a lot about the SIGNAL LAMP scenario in the field of

communication. This circuit is used for safe highway driving. This circuit inform the

driver about the approaching vehicle. It also help the driver if the driver wants to stop for

sometime on highway. It saves battery power.

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REFRENCE

http:// www.wikipedia.com/

http://www.circuitstoday.com /

http://www.allaboutcircuit.com/

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