Automatic Railway

7/31/2019 Automatic Railway

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B.TECH PROJECT REPORTON

Automatic Railway Crossing

Controller

By

:-

AKNASHA GAHLOT

(0832140001)

MANOJ SHARMA (0832140002)

MOHIT AGGRAWAL

(0837940004)

SOURABH TYAGI (0837940009)

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M.E Deptt. M.E. Deptt.

ACKNOWLEDGEMENT

We are grateful to Mr.Abhishek goel, Asst. Lecturer, Mech.

Department, TITM Mawana road Meerut encouragement and

guidance during the preparation of this work.

We express our sincere gratitude to Dr.K.M Aggrawal, H.O.D.,

M.E Department, Translam Institute of Technology &

Management, Meerut for his invaluable suggestions and

constructive criticism regarding this report.

Last but not the least, we are thankful to all those who helped

us in any way to prepare this report.

Mr. HARIOM TRIPATHI

Mr. ANIL JOSI

Mr. ANUPAM Kumar

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CONTENTS

INTRODUCTION

PLATFORM USED

AIM OF THE PROJECT

BLOCK DIAGRAM

WORKING OF THE PROJECT

CIRCUIT DIAGRAM

COMPONENT LIST

CIRCUIT DESCRIPTION

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In his generation everything is going to be automated human involvement is going to

decreases. Technology is growing day by day using the embedded system designing

here we have designed Automatic railway crossing which is a embedded system based

design, embedded system is a combination of hardware and software it functioning is

based on the microcontroller .In this project the railway barrier automatically close

when the train is few Kilometer away from the barrier and automatically gets open

when the train crosses that barrier and goes few Kilometer ahead of it.

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PLATFORM USED

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Hardware requirements :

1) LM7805 Regulator

2) Resistors

3) Capacitors

4) Transistors

5) Connectors

6) IR Sensor

7) BUZZER

8) Liquid crystal display

9) PCB developing equipments

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AIM OF THE

PROJECT

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The Aim of this project is to design an automatic railway crossing system by using

controller and Pressure sensor ,Pressure sensor is used for finding the distance of the

train ,at a fixed distance these sensor is placed whenever a train passes it ,Ir transmitter

generate a low signal pulse that is received by the controller ,passes to the circuit which

give us the information about the train .when train if few k.m away from the barrier the

barrier will closes and after train crosses it ,the barrier open and allow the traffic to

cross it . This system is reliable and much effective then the previous railway crossing

system in which a human has to be involve all the time, this system work also when

their will be no person to operate the barriers opening and closing .

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BLOCK DIAGRAM

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12

PIC

CONTROLLER

POWER

SUPPLY

DISPLAY

ON LCD

PRESSURE

SENSOR

BuzzerMotor to

control barrier


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Here we are using a microcontroller ,PRESSURE sensor ,relay ,motor and LCD for

proper functioning of the system .we are presenting a model of the system in which we

are using a toy train which representing the actual train .we have placed three sensor

at fixed distance along the track whenever the train crosses it and sensor press ,the pulse

that it is giving to the microcontroller initially, changes from high to low this low pulse

is applied to the pin of the microcontroller on sensing this pin microcontroller run the

buzzer and display the distance of the train ,the distance display will be the distance

loaded by programmer during programming of the microcontroller when it crossed the

IR sensor at which is 3 Km away from the barrier ,the microcontroller sense it and it

turn on a relay which turn on a motor and the barriers closes, H bridge is used here for

changing the direction of rotation of motor because it has to rotate in opposite direction

for closing the barrier when train crosses it .

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Attach the hardcopyof the ckt

diagram

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POWER SUPPLY SECTION:

Consists of:

1. RLMT Connector--- It is a connector used to connect the stepdown transformer to the bridge rectifier.

2. Bridge Rectifier --- It is a full wave rectifier used to convert

ac into dc , 9-15v ac made by transformer is converted into dcwith the help of rectifier.

3. Capacitor: -----It is an electrolytic capacitor of rating1000M/35V used to remove the ripples. Capacitor is thecomponent used to pass the ac and block the dc.

4. Regulator: ----LM7805 is used to give a fixed 5v regulated

supply.

5. Capacitor: -----It is again an electrolytic capacitor 10M/65vused for filtering to give pure dc.

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3. Reset section: It consists of an rc network consisting of10M/35V capacitor and one resistance of 1k. This section is usedto reset the controller connected at pin no.9 of AT89c51.

DISPLAY SECTION:

LCD (LIQUID CRYSTAL DISPLAY)

MICROCONTROLLER BASED LCD DISPLAY ,this project is an embedded project . Embedded is the

combination of software and hardware before designing any embedded project it is the first step to design the

proper hardware for the desired application. Here we are interfacing the LCD, LIQUID CRYSTAL DISPLAY

with the Microcontroller, we are using ATMEL series 51 controller 89c51 controller. It is a 40 pin IC, the first

step while designing hardware is to design the required power supply as the controller operates on +5 v supply

so first we have to design the regulated supply with the help of transformer, regulator and filtering capacitor.

Next step is the necessary connections of the controller like reset and the crystal oscillator for resetting and

speed respectively.

Then comes the LCD interfacing ,we are using 16x2 LCD for display, pin no. 7 to 14 are the data lines of the

LCD which has to be interfaced with the microcontroller input/output pins. Port p0 has been used for the

interfacing of data lines.

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PCB LAYOUT

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Attach the hard

copy of the pcblayout

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Prepare the layout of the circuit (positive).

Cut the photo film (slightly bigger) of the size of the layout.

Place the layout in the photo printer machine with the photo film aboveit. Make sure that the bromide (dark) side of the film is in contact withthe layout.

Switch on the machine by pressing the push button for 5 sec.

Dip the film in the solution prepared (developer) by mixing thechemicals A & B in equal quantities in water.

Now clean the film by placing it in the tray containing water for 1 min.

After this, dip the film in the fixer solution for 1 min. now the negative oftheCircuit is ready.

Now wash it under the flowing water.

Dry the negative in the photocure machine.

Take the PCB board of the size of the layout and clean it with steel woolto make the surface smooth.

Now dip the PCB in the liquid photoresist, with the help of dip coatmachine.

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Liquid crystal display(LCD)

A liquid crystal display (commonly abbreviated LCD) is a thin, flat

display device made up of any number of color or monochromepixels

arrayed in front of a light source or reflector. It is prized by engineers

because it uses very small amounts ofelectric power, and is therefore

suitable for use in battery-powered electronic devices.Each pixel of

an LCD consists of a layer of perpendicular molecules aligned

between two transparent electrodes, and two polarizing filters, the

axes of polarity of which are perpendicular to each other. With no

liquid crystal between the polarizing filters, light passing through one

filter would be blocked by the electrodes. The surfaces of the

electrodes that are in contact with the liquid crystal material aretreated so as to align the liquid crystal molecules in a particular

direction. This treatment typically consists of a thin polymer layer

that is unidirectional rubbed using a cloth (the direction of the liquid

crystal alignment is defined by the direction of rubbing). Before

applying an electric field, the orientation of the liquid crystal

molecules is determined by the alignment at the surfaces. In a

twisted nomadic device (the most common liquid crystal device), the

surface alignment directions at the two electrodes are perpendicular,

and so the molecules arrange themselves in a helical structure, or

twist. Because the liquid crystal material is birefringent, light passing

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termed the magnetizing current; in the ideal transformer it is considered to be

negligible. The MMF drives flux around the magnetic circuit of the core.

Figure 26: The ideal transformer as a circuit element

An electromotive force (EMF) is induced across each winding, an effect known as

mutual inductance. The windings in the ideal transformer have no resistance and

so the EMFs are equal in magnitude to the measured terminal voltages. In

accordance with Faraday's law of induction, they are proportional to the rate of

change of flux:

and

Equation 7: EMF induced in primary and secondary windings

where:

and are the induced EMFs across primary and secondary windings,

and are the numbers of turns in the primary and secondary windings,

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Prior to availability of integrated electronics, such a bridge rectifier was always constructed

from discrete components. Since about 1950, a single four-terminal component containing

the four diodes connected in the bridge configuration became a standard commercial

component and is now available with various voltage and current ratings.

2.2.2 Output Smoothing

For many applications, especially with single phase AC where the full-wave bridge serves

to convert an AC input into a DC output, the addition of a capacitor may be important

because the bridge alone supplies an output voltage of fixed polarity but pulsating

magnitude.

Figure 11: Bridge Rectifier with smoothen output

The function of this capacitor, known as a 'smoothing capacitor' (see also filtercapacitor) is to lessen the variation in (or 'smooth') the raw output voltage

waveform from the bridge. One explanation of 'smoothing' is that the capacitor

provides a low impedance path to the AC component of the output, reducing the

AC voltage across, and AC current through, the resistive load. In less technical

terms, any drop in the output voltage and current of the bridge tends to be

cancelled by loss of charge in the capacitor. This charge flows out as additional

current through the load. Thus the change of load current and voltage is reduced

relative to what would occur without the capacitor. Increases of voltage

correspondingly store excess charge in the capacitor, thus moderating the change

in output voltage / current.

Thecapacitor and the load resistance have a typical time constant = RC where C

and R are the capacitance and load resistance respectively. As long as the load

resistor is large enough so that this time constant is much longer than the time of

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Figure 16: TOP IC view of LM 317

The LM317 is versatile in its applications, including uses in programmable output

regulation and local on-card regulation. Or, by connecting a fixed resistor between the

ADJUST and OUTPUT terminals, the LM317 can function as a precision current regulator. An

optional output capacitor can be added to improve transient response. The ADJUST

terminal can be bypassed to achieve very high ripple-rejection ratios, which are difficult to

achieve with standard three-terminal regulators. The LM317 is characterized for operation

over the

virtual junction temperature range of 0C to 125C.

RELAYS

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temperature compensation components and regulated power supplies, together with

environmental control (good ventilation and ambient temperature regulation) and

battleship mechanical construction. This has been done in some communications

receivers used by the military and commercial HF communication receivers built in the

1950-1965 era, before the widespread use of digital frequency synthesis. But thesereceivers were extremely expensive, large, and heavy. Many modern consumer grade

AM, FM, and shortwave receivers employing crystal controlled digital frequency

synthesis will do as well or better from a frequency stability standpoint.

An oscillator is basically an amplifier and a frequency selective feedback network (Fig

1). When, at a particular frequency, the loop gain is unity or more, and the total phase

shift at this frequency is zero, or some multiple of 360 degrees, the condition for

oscillation is satisfied, and the circuit will produce a periodic waveform of this

frequency. This is usually a sine wave, or square wave, but triangles, impulses, or other

waveforms can be produced. In fact, several different waveforms often are

simultaneously produced by the same circuit, at different points. It is also possible to

have several frequencies produced as well, although this is generally undesirable.

CAPACITOR

A capacitor orcondenser is apassiveelectronic component consisting of a pair of

conductors separated by a dielectric (insulator). When apotential difference (voltage)exists across the conductors, an electric field is present in the dielectric. This field stores

energy and produces a mechanical force between the conductors. The effect is greatest

when there is a narrow separation between large areas of conductor, hence capacitor

conductors are often called 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 ofleakage current. The conductors and leads introduce an equivalent

series resistance and the dielectric has an electric field strength limit resulting in a

breakdown voltage.

Capacitors are widely used in electronic circuits to block the flow ofdirect current

while allowing alternating current to pass, to filter out interference, to smooth the output

ofpower supplies, and for many other purposes. They are used in resonant circuits in

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radio frequency equipment to select particularfrequencies from a signal with many

frequencies.

Theory of operationMain article: Capacitance

Charge separation in a parallel-plate capacitor causes an internal

electric field. A dielectric (orange) reduces the field and increases the

capacitance.

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A simple demonstration of a parallel-plate capacitor

A capacitor consists of two conductors separated by a non-conductive region.The non-

conductive substance is called the dielectric medium, although this may also mean a

vacuum or a semiconductordepletion region chemically identical to the conductors. Acapacitor is assumed to be self-contained and isolated, with no net electric charge and

no influence from an external electric field. The conductors thus contain equal and

opposite charges on their facing surfaces, and the dielectric contains an electric field.

The capacitor is a reasonably general model for electric fields within electric circuits.

An ideal capacitor is wholly characterized by a constant capacitance C, defined as the

ratio of charge Q on each conductor to the voltage Vbetween them

Sometimes charge buildup affects the mechanics of the capacitor, causing the

capacitance to vary. In this case, capacitance is defined in terms of incremental changes:

In SI units, a capacitance of one farad means that one coulomb of charge on each

conductor causes a voltage of one volt across the device.

Workmust be done by an external influence to move charge between the conductors in

a capacitor. When the external influence is removed, the charge separation persists and

energy is stored in the electric field. If charge is later allowed to return to its equilibrium

position, the energy is released. The work done in establishing the electric field, and

hence the amount of energy stored, is given by:

RESISTOR

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Resistors are used to limit the value of current in a circuit. Resistors offer opposition to

the flow of current. They are expressed in ohms for which the symbol is . Resistors

are broadly classified as

(1)Fixed Resistors(2)Variable Resistors

Fixed Resistors :

The most common of low wattage, fixed type resistors is the molded-carbon

composition resistor. The resistive material is of carbon clay composition. The leads are

made of tinned copper. Resistors of this type are readily available in value ranging from

few ohms to about 20M, having a tolerance range of 5 to 20%.They are quite inexpensive. The relative size of all fixed

resistors changes with the wattage rating.

Another variety of carbon composition resistors is the metalized type. It is

made by deposition a homogeneous film of pure carbon over a glass, ceramic

or other insulating core. This type of film-resistor is sometimes called the

precision type, since it can be obtained with an accuracy of 1%.

Lead Tinned Copper Material

Colour Coding Molded Carbon Clay Composition

Fixed Resistor

A Wire Wound Resistor :

It uses a length of resistance wire, such as macram. This wire is wounded on to a round

hollow porcelain core. The ends of the winding are attached to these metal pieces

inserted in the core. Tinned copper wire leads are attached to these metal pieces. This

assembly is coated with an enamel coating powdered glass. This coating is very smooth

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and gives mechanical protection to winding. Commonly available wire wound resistors

have resistance values ranging from 1 to 100K, and wattage rating up to about

200W.

Coding Of Resistor :

Some resistors are large enough in size to have their resistance printed on the body.

However there are some resistors that are too small in size to have numbers printed on

them. Therefore, a system of color coding is used to indicate their values. For fixed,

mounded composition resistor four color bands are printed on one end of the outer

casing. The color bands are always read left to right from the end that has the bands

closest to it. The first and second band represents the first and second significant digits,of the resistance value. The third band is for the number of zeros that follow the second

digit. In case the third band is gold or silver, it represents a multiplying factor of 0.1to

0.01. The fourth band represents the manufactures tolerance.

RESISTOR COLOUR CHART

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5 green

0 black

1 brown

2 red

3 orange

4 yellow

6 blue

7 purple

8 silver

9 white

0 black

1 brown

2 red

3 orange

4 yellow

6 blue

7 purple

8 silver

9 white

5green

5 green

0 black

1 brown

2 red

3 orange

4 yellow

6 blue

7 purple

8 silver

9 white

5 green

0 black

1 brown

2 red

3 orange

4 yellow

6 blue

7 purple

8 silver

9 white


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For example, if a resistor has a color band sequence: yellow,violet, orange and gold

Then its range will be

Yellow=4, violet=7, orange=10, gold=5% =47K 5% =2.35K

Most resistors have 4 bands:

The first band gives the first digit. The second band gives the second digit. The third band indicates the number of zeros. The fourth band is used to show the tolerance (precision)

of the resistor.

This resistor has red (2), violet (7), yellow (4 zeros) and gold bands.

So its value is 270000 = 270 k .

The standard color code cannot show values of less than 10 . To show these small

values two special colors are used for the third band: gold, which means 0.1 andsilver which means 0.01. The first and second bands represent the digits as

normal.

For example:

red, violet, gold bands represent 27 0.1 = 2.7

blue, green, silverbands represent 56 0.01 = 0.56

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The fourth band of the colour code shows the tolerance of a resistor. Tolerance is

the precision of the resistor and it is given as a percentage. For example a 390

resistor with a tolerance of 10% will have a value within 10% of 390 , between

390 - 39 = 351 and 390 + 39 = 429 (39 is 10% of 390).

A special colour code is used for the fourth band tolerance:

silver10%, gold 5%, red 2%, brown 1%.

If no fourth band is shown the tolerance is 20%.

VARIABLE RESISTOR: In electronic circuits, sometimes it

becomes necessary to adjust the values of currents and

voltages. For n example it is often desired to change thevolume of sound, the brightness of a television picture etc.

Such adjustments can be done by using variable resistors.

Although the variable resistors are usually called rheostats inother applications, the smaller variable resistors commonly usedin electronic circuits are called potentiometers.

TRANSISTORS

A transistor is an active device. It consists of two PN junctions

formed by sandwiching either p-type or n-type semiconductor

between a pair of opposite types.

There are two types of transistor:1.n-p-n transistor2.p-n-p transistor

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Collector : The section on the other side that collects the

charge is called collector. The collector is always reversed

biased.

Base : The middle section which forms two pn-junctions

between the emitter and collector is called base.

A transistor raises the strength of a weak signal and thus acts

as an amplifier. The weak signal is applied between emitter-

base junction and output is taken across the load Rc

connected in the collector circuit. The collector current flowing

through a high load resistance Rc produces a large voltage

across it. Thus a weak signal applied in the input appears in

the amplified form in the collector circuit.

Heat sink

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GaP and GaAsP are higher band gap materials. Gallium phosphate is

an indirect band gap semiconductor and has poor efficiency because

band to band transitions are not normally observed.

Gallium Arsenide Phosphate is a tertiary alloy. This material has aspecial feature in that it changes from being direct band gap

material.

Blue LEDs are of recent origin. The wide band gap materials such as

GaN are one of the most promising LEDs for blue and green emission.

Infrared LEDs are suitable for optical coupler applications.

DIODE

ACTIVE COMPONENT-

Active component are those component for not any other component are used its

operation. I used in this project only function diode, these component description are

described as bellow.

SEMICONDUCTOR DIODE-

A PN junctions is known as a semiconductor or crystal diode.A crystal diode has two

terminal when it is connected in a circuit one thing is decide is weather a diode is

forward or reversed biased. There is a easy rule to ascertain it. If the external CKT is

trying to push the conventional current in the direction of error, the diode is forward

biased. One the other hand if the conventional current is trying is trying to flow

opposite the error head, the diode is reversed biased putting in simple words.

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1. If arrowhead of diode symbol is positive W.R.T Bar of the symbol, the diode

is forward biased.

2. The arrowhead of diode symbol is negative W.R.T bar , the diode is the

reverse bias.

When we used crystal diode it is often necessary to know that which end is arrowhead

and which end is bar. So following method are available.

1. Some manufactures actually point the symbol on the body of the diode

e. g By127 by 11 4 crystal diode manufacture by b e b.

2. Sometimes red and blue marks are on the body of the crystal diode. Red mark

do not arrow wheres blue mark indicates bar e .g oa80 crystal diode.

ZENER DIODE-

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It has been already discussed that when the reverse bias on a crystal diode is increased a

critical voltage, called break down voltage. The break down or zener voltage depends

upon the amount of doping. If the diode is heavily doped depletion layer will be thin

and consequently the break down of he junction will occur at a lower reverse voltage.

On the other hand, a lightly doped diode has a higher break down voltage, it is called

zener diode

.

A properly doped crystal diode, which has a sharped break down voltage, is known as a

zenor diode.

In this project I used semiconductor diode for bridge rectifies, two-crystal diode

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CONCLUSION

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CONCLUSION:

This Automatic Railway Crossing Controller overcomes the drawbacks of earlier

system. We are able to implement successfully our mission which is to develop a fire

protection system that able to provide the solution to the problems faced by fireaccident .

The developing of this project has been a learning experience for all team members and

would prove as a milestone in their academic career. The achievement of this project

are:-

i. The project has achieved its set target well in Time and Budget.

ii. Based on cutting edge technology called Embedded development which is

niche in the market today and its future is much bright.

iii. The product developed is ready for implementation and can bring financial

benefits too by sale in the market.

So, we conclude that the advanced security system is still far away from the perfect, but

we believe we have laid the groundwork to enable it to improve out of sight.

BIBLIOGRAPHY61


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Mehta V.K., Principles of Electronics S.Chand & Co. Ltd., New Delhi

Intel Microcontroller and Features

Tata Mc Graw Hill Publishing Ltd., New Delhi

Boylstead Robert & Nasceslsky Louis Electronic Devices &CircuitTheory Prentice Hall of India Private Ltd., New Delhi

Millman Jacob & Halkias C. Christos Integrated Electronics

Tata Mc Graw Hill Publishing Ltd., New Delhi

WEB SITES

www.microtutorials.com www.datasheets.com www.archives.com

www.nationalsemiconductors.com www.atmel.com www.seimens.com www.fairchildsemiconductors.com
http://www.microtutorials.com/http://www.datasheets.com/http://www.archives.com/http://www.nationalsemiconductors.com/http://www.atmel.com/http://www.seimens.com/http://www.fairchildsemiconductors.com/http://www.microtutorials.com/http://www.datasheets.com/http://www.archives.com/http://www.nationalsemiconductors.com/http://www.atmel.com/http://www.seimens.com/http://www.fairchildsemiconductors.com/

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