The main objective of this project is to design an intelligent auto traffic signal control system. Traffic congestion is one of the major issues to be considered. Generally Vehicular traffic Intersects at the junctions of the road and are controlled by the traffic signals .Traffic signals Need a good coordination and control to ensure the smooth and safe flow of the vehicular traffic. During the rush hours, the traffic on the roads is at its peak. Also, there is a possibility for the Emergency vehicles to stuck in the traffic jam. Therefore; there is a need for the dynamic control of the traffic during rush hours. Hence I propose a smart traffic signal controller .The proposed System tries to minimize the possibilities of traffic jams, caused by the traffic lights, to some Extent by clearing the road with higher density of vehicles and also provides the clearance for the Emergency vehicle if any. The system is based on the AVR micro controller and IR sensors Technology.

1. TRAFFIC SIGNAL CONTROL USING IR SENSORS
SavitribaiPhule Pune University
A
Seminar Report
On
“TRAFFIC SIGNAL CONTROL USING IR SENSORS”
Submitted by
KunalKabra.Seat No.: T120863029
Under the Guidance of
Prof. S. A. Shejwalkar
In partial fulfilment for the award of
Third year
Electronics & Telecommunication Engineering
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2. TRAFFIC SIGNAL CONTROL USING IR SENSORS
Pune VidyarthiGriha’s College of Engineering, Nashik
Department of Electronics and Telecommunication Engineering
Pune VidyarthiGriha’s College of Engineering
Nashik- 4
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3. TRAFFIC SIGNAL CONTROL USING IR SENSORS
1. INTRODUCTION
1.1 Introduction
It is an intelligent traffic controlling system.
Our present methodology adopted for traffic controlling is based upon the fix timing.
Each side has to wait for the fix time and they are allowed to cross the road for the limited fix
time.
This is feasible during normal traffic but fails during heavy rush.
This waste the time of commuters as well as increases rush many folds.
This problem can be tackled by adopting traffic monitoring system based on density of vehicles.
This uses vehicles density as its tool for measuring the rush on the road.
Based upon the calculated density of vehicles the traffic light are being controlled to manage the
traffic.
1.2 Project overview
The main objective of this project is to design an intelligent auto traffic signal control system.
Traffic congestion is one of the major issues to be considered. Generally Vehicular traffic
Intersects at the junctions of the road and are controlled by the traffic signals .Traffic signals
Need a good coordination and control to ensure the smooth and safe flow of the vehicular traffic.
During the rush hours, the traffic on the roads is at its peak. Also, there is a possibility for the
Emergency vehicles to stuck in the traffic jam. Therefore; there is a need for the dynamic control
of the traffic during rush hours. Hence I propose a smart traffic signal controller .The proposed
System tries to minimize the possibilities of traffic jams, caused by the traffic lights, to some
Extent by clearing the road with higher density of vehicles and also provides the clearance for
the Emergency vehicle if any. The system is based on the AVR micro controller and IR sensors
Technology.
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4. TRAFFIC SIGNAL CONTROL USING IR SENSORS
2. LITERATURE SURVEY
The present practices for traffic signal control are given below.
2.1 Simple Traffic Management Scheme
The traffic is control by one person only. If there are four roads from where vehicles are
coming then the man should have control in traffic. He has to release the vehicles one by one
road. In this scheme there is very use of manpower and its not easy to handle when more
traffic is there.
2.2 Automatic Traffic Management Scheme
The most widely used automatic system. Uses simple time based system which works on
time interval basis which is now inefficient for random and non-uniform traffic. but time
interval basis is very time wasting its not a fast process.
2.3 Intelligent Traffic Management Scheme using Wireless Technologies
This is used to sense presence of traffic near any circle and junction and then able to
route the traffic based on the density in desired direction.
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5. TRAFFIC SIGNAL CONTROL USING IR SENSORS
3. HARDWARE DESCRIPTION
3.1 Introduction
In this chapter the block diagram of the project and design aspect of independent
Modules are considered. Block diagram is shown in figure.
Fig No. 3.1 Density Based Traffic Light Signal Control System
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6. TRAFFIC SIGNAL CONTROL USING IR SENSORS
3.1.1 Working
Our project density based traffic light control is an automated way of controlling signals in
accordance to the density of traffic in the roads. IR sensors are placed in the entire intersecting
road at fixed distances from the signal placed in the junction. The time delay in the traffic
signal is set based on the density of vehicles on the roads.
The IR sensors are used to sense the number of vehicles on the road. According to the IR
count, microcontroller takes appropriate decisions as to which road is to be given the highest
priority and the longest time delay for the corresponding traffic light.
3.2 The main blocks of this project are
1. PIC Micro controller (18F4550)
2. Battery Supply
3. IR Sensors
4. LED
The description of each of the component used in the project is given as below
3.3 PIC Microcontroller
Fig No. 3.2 Pic Microcontroller
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7. TRAFFIC SIGNAL CONTROL USING IR SENSORS
Introduction to microcontroller
Circumstances that we find ourselves in today in the field of microcontrollers had their
beginnings in the development of technology of integrated circuits. This development has made
it possible to store hundreds of thousands of transistors into one chip. That was a prerequisite for
production of microprocessors, and the first computers were made by adding external peripherals
such as memory, input-output lines, timers and other. Further increasing of the volume of the
package resulted in creation of integrated circuits. These integrated circuits contained both
processor and peripherals. That is how the first chip containing a microcomputer, or what would
later be known as a microcontroller came about.
Description
Introduction to PIC Microcontrollers
PIC stands for Peripheral Interface Controller given by Microchip Technology to
identify its single-chip microcontrollers. These devices have been very successful in 8-bit
microcontrollers. The main reason is that Microchip Technology has continuously upgraded the
device architecture and added needed peripherals to the microcontroller to suit customers'
requirements. The development tools such as assembler and simulator are freely available on the
internet at www.microchip.com.
Popularity of the PIC microcontrollers is due to the following factors
1. Speed: Harvard Architecture, RISC architecture, 1 instruction cycle = 4 clock cycles.
2. Instruction set simplicity: The instruction set consists of just 35 instructions.
(as opposed to111 instructions for 8051)
3. Power-on-reset and brown-out reset. Brown-out-reset means when the power supply
goes below a specified voltage (say 4V), it causes PIC to reset; hence malfunction is
avoided.
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8. TRAFFIC SIGNAL CONTROL USING IR SENSORS
4. PIC microcontroller has four optional clock sources.
Low power crystal
Mid-range crystal
High range crystal
RC oscillator (low cost).
5. Programmable timers and on-chip ADC.
6. Up to 12 independent interrupt sources.
7. Powerful output pin control (25 mA (max.) current sourcing capability per pin.)
8. I/O port expansion capability.
3.3.1 Pin diagram
Fig No. 3.3 Pin Diagram Of Pic18f4550
PIC18F4550 is a 40 pin microcontroller. It has 5 ports port A, port B, port C, port D, port E. All
the pins of the ports are for interfacing input output devices.
1. Port A: It consists of 6 pins from A0 to A5
2. Port B: It consists of 8 pins from B0 to B7
3. Port C: It consists of 8 pins from C0 to C7
4. Port D: It consists of 8 pins from D0 to D7
5. Port E: It consists of 3 pins from E0 to E2
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9. TRAFFIC SIGNAL CONTROL USING IR SENSORS
The rest of the pins are mandatory pins these should not be used to connect input/output devices.
1. Pin 1 is MCLR (master clear pin) pin also referred as reset pin.
2. Pin 13, 14 are used for crystal oscillator to connect to generate a frequency of about
20MHz.
3. Pin 11, 12 and31, 32 are used for voltage supply VDD(+)and VSS(-)
PIC 18F4550 Specification
1. RAM -368 bytes
2. EEPROM- 256 bytes
3. Flash Program Memory- 8k words
4. Operating Frequency DC to 20MHz
5. I/O port - Port A,B,C,D,E
3.4 Power Supply
The present chapter introduces the operation of power supply circuits built
using filters, rectifiers and then voltage regulators. Starting with an ac voltage, then filtering to a
dc voltage is obtained by rectifying the ac voltage, then filtering to a dc level and finally,
regulating to obtain a desired fixed dc voltage. The regulation is usually obtained from an IC
voltage regulator unit, which takes a dc voltage and provides a somewhat lower dc voltage,
which remains the same even if the input dc varies, or the output load connected to the dc
voltage changes.
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10. TRAFFIC SIGNAL CONTROL USING IR SENSORS
TRANSFORMER
A transformer is an electrical device which is used to convert electrical power from one
Electrical circuit to another without change in frequency.
Transformers convert AC electricity from one voltage to another with little loss of power.
Transformers work only with AC and this is one of the reasons why mains electricity is AC.
Step-up transformers increase in output voltage, step-down transformers decrease in output
voltage. Most power supplies use a step-down transformer to reduce the dangerously high mains
voltage to a safer low voltage.
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Fig No. 3.4 Components Of Linear Power Supply

11. TRAFFIC SIGNAL CONTROL USING IR SENSORS
REGULATOR
Voltage regulator ICs is available with fixed (typically 5, 12 and 15V) or variable output
voltages. The maximum current they can pass also rates them. Negative voltage regulators are
available, mainly for use in dual supplies. Most regulators include some automatic protection
from excessive current (‘overload protection’) and overheating (‘thermal protection’). Many of
the fixed voltage regulators ICs have 3 leads and look like power transistors, such as the 7805
+5V 1A regulator shown on the right. The LM7805 is simple to use. You simply connect the
positive lead of your unregulated DC power supply (anything from 9VDC to 24VDC) to the
Input pin, connect the negative lead to the Common pin and then when you turn on the power,
you get a 5 volt supply from the output pin.
3.5 IR Sensors
Introduction to IR Sensors
PIC based traffic control system is an application specific project, which is used to control the
traffic. An embedded system is developed which consists of a PIC, IR transmitter and receiver,
LED’s.
Fig No. 3.5 IR Sensing Circuit
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12. TRAFFIC SIGNAL CONTROL USING IR SENSORS
3.5.1 IR TRANSMITTER AND RECIEVER
The purpose of the transmitter is to transform the information we want to send into a signal that
can be propagated by the channel. In the case of our wired copper channel, this means we want
the information to be transformed into a modulated voltage level, something like the pulse train.
For a wireless channel, however, the transmitter needs to encode the information onto an EM
wave that can be easily propagated.
Fig No. 3.6 IR Transmitter
The IR transmitter part consists of an Infra-red light emitting diode that can capable of sending
modulated data within infra-red band. To match the receiver frequency the data is modulated at
38.7 KHZ by configuring 555 timer at a stable mode of operation, which generates frequency
using the components R2 and C2 as shown in above fig. This frequency can be varied over a
long range just by varying the preset R1 and C1.The transmitter usually is a battery powered
handset. It should consume as little power as possible, and the IR signal should also be as
strong as possible to achieve an acceptable control distance.
Preferably it should be shock proof as well. Many chips are designed to be used as IR
transmitters. The older chips were dedicated to only one of the many protocols that were
invented. Nowadays very low power microcontrollers are used in IR transmitters for the simple
reason that they are more flexible in their use. When no button is pressed they are in a very low
power sleep mode, in which hardly any current is consumed. The processor when wakes up to
transmit the appropriate IR command only a key is pressed
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13. TRAFFIC SIGNAL CONTROL USING IR SENSORS
An emitter follower circuit can avoid this. The 2 diodes in series will limit the pulses on the
base of the transistor to 1.2V. The base-emitter voltage of the transistor subtracts O.6V
from that, resulting in constant amplitude of O.6V at the emitter. This constant amplitude
across a constant resistor results in current pulses of a constant magnitude. Calculating the
current through the LED is simply applying ohm' law.
3.6 LED’S
Fig No. 3.7 LED’s Interfacing
LED (light emitting diode) color is characterized by the wavelength it emits. The
peak emission wavelength differs according to the energy released during recombination. This
energy differs according to the LED material used. Mixed crystals of GaP & GaAs are used. By
varying the mixing ratio “X”, different luminous colors from red to yellow are obtained.
LEDs can typically draw up to 30mA.A current limiting resistor is mandatory to protect
both the microcontroller & LED. Even connecting a led through a resistor is not advisable in
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14. TRAFFIC SIGNAL CONTROL USING IR SENSORS
case of 8051.A NPN or a PNP transistor may be used. This way even higher currents can be
used. Ohms law can be used to calculate the value of the current limiting resistor, i.e I=V/R.
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15. TRAFFIC SIGNAL CONTROL USING IR SENSORS
4. PCB DESIGNING
4.1 General Description
The PCB layout for the circuit is attached. Board consists of insulating material coated with
conducting material. Mostly copper- coated boards are used instead fo copper, silver and gold
can also be used, but as copper is cheaper mostly it is preferred. The metal conducting pattern
serves as connecting medium for electronic components that are assembled on the board
components are mounted by leads passing through the holes that are drilled or punch on the
based material and the foil. These leads are soldered to the conducting pattern to form complete
PCB. The base or insulating material used for PCB is glass, glass epoxy paper, polyester, paper
phenolic etc. The copper foil on the base meterial is developed by process of electrode position
in etching process.
Some of the etchant are used as follows
1. FeCl3
2. Cucl2
3. Chromic Acid, etc
4. But FeCl3 is most commonly used in etching process.
5. PCB acts as a heat sink.
4.2 Artwork of PCB
Perfect artwork is most important process in production of PCB. The circuit is initially tested and
location of component is fixed. Artwork is the drawing showing conduction pattern on PCB .
After testing the circuit a rough layout is prepared on paper then that layout is transferred on
PCB by using PCB aids. The artwork can also be prepared on transparent paper with sticking
tapes and pads self- adhesive (stickers) in various ranges.
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16. TRAFFIC SIGNAL CONTROL USING IR SENSORS
4.3 Filming of PCB
To prepare a PCB at home following procedure is adopted
Measure the dimensions of all components for e.g. Resistors Capacitor , Inductors, etc and
prepare a layout by using components mounting rules
1. Using trace paper or carbon paper draws the mirror image of the figure.
2. Draw this mirror image on Cu coating of PCB by using PCB pen, pencil or tapes and
pads then drill the hole by using drilling machine
3. After drying the paint put the PCB in FeCl3 solution for etching . If you want fast etching
add some drops of HCL during etching unwated Cu is dissolved in FeCl3.
4. After etching wash it with water and if you to remove paint then use acetone.
5. Then mount the component on opposite sides of a track.
6. Cut the leads of proper length and solder all the terminals of the components.
7. In this way PCB is fabricated manually.
For PCB designing you should have following things
1. Detail circuit diagram
2. Physically each component with you
3. Determination of the size of PCB
4. Layout & Filming
5. PCB manufacturing
6. Bear board testing
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17. TRAFFIC SIGNAL CONTROL USING IR SENSORS
4.4 Actual PCB designing
Fig No. 4.1 Actual PCB
Cutting the larger copper clad plastes in required size Pieces accroding to the measurement of the
actual layout of the circuit a small copper clad was also used for the power supply. Proper case
should be taken while cutting the Copper clad should be symmetric.
4.5 Cleaning copper clad
For cleaning the copper clade ,first of all the fecl3 solution was completely me a dilute selution
(by adding water fecl3).
Draw the PCB layout of the circuit on paper considering actual component size. Consider the
actual size of the components and the conduction line the layout of the circuit was drawn on the
paper. First of all we should consider the actual size of the integrated circuit, displays & many
more. While constructing the layout it should be notice that
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18. TRAFFIC SIGNAL CONTROL USING IR SENSORS
1. Fewer jumpers are more preferable because to make the circuits more compact, more neat
in look.
2. For conducting line we should go for more caned line instead of 90-degrecue due to this
also the circuit become more compact.
4.6 Tracing of layout from paper clad
First of all the actual circutit layout is taken on the tracing paper with exact dimension of the
components. Now placing this tracing paper on the copper clad under a carbon paper traced the
layout on the copper clad. It should be noticed that the tracing on the clad should be accurate.
4.7 Applying non-etching materials on the layout
Applying the non-etching materials on the layout is done manually . The non-etching materials
are drafting ads, oil paints, etc . on the PCB drafting aids are used, because more linearity
conducting are obtained. The drafting aids are different shapes & z-size for every components
are should be no crack on the drafting aids, because due at this after etching there will be no
conduction between two lines.
4.8 Etching procedure
After applying the non-etching on the copper clad then this copper clad is kept in the fecl3
solution for etching procedure. The etching procedure longs for the about 5 to 6 hours. During
the etching procedure the copper under the drafting aids does not get etched, while all other
copper on the clad gets etched & only the layout remain.
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19. TRAFFIC SIGNAL CONTROL USING IR SENSORS
4.9 Cleaning the PCB & remaining non-etch materials
After the etching the cleaning of PCB is done. It is done with the help of the soap solution &
brush to remove the transferred pattern with the cotton swab-dipped in pattern remover solution.
Against wash with coup & water & dry it.
4.10 Drilling
After the PCB is ready, drilling is necessary. Drilling is done with the help of the hand drill or
drilling machine. For mounting of components proper drilling (holes) are necessary. The holes
are of the dimension so that the terminals of each component and pins of the JC can easily pass
through it to make a contact with the conducting line on the PCB.
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20. TRAFFIC SIGNAL CONTROL USING IR SENSORS
5. SOFTWARE DESCRIPTION
This project is implemented using following software‘s
Proteus 8 (Embedded C) – for designing circuit.
Software description
5.1 PROTEUS 8
Proteus 8 is a single application with many service modules offering different functionality
(schematic capture, PCB layout, etc.). The wrapper that enables all of the various tools to
communicate with each other consists of three main parts.
5.1.2 Application Framework
Proteus 8 consists of a single application (PDS.EXE). This is the framework or container which
hosts all of the functionality of Proteus. ISIS, ARES, 3DV all open as tabbed windows within
this framework and therefore all have access to the common database.
5.1.3 Common Database
The common database contains information about parts used in the project. A part can contain
both a schematic component and a PCB footprint as well both user and system properties. Shared
access to this database by all application modules makes possible a huge number of new features,
many of which will evolve over the course of the Version 8 lifecycle.
5.2.3 Live Netlist
Together with the common database the maintenance of a live netlist allows all open modules to
automatically reflect changes. The most obvious example of this is wiring in ISIS producing
ratsnest connections in ARES but it goes much further than that. The new Bill of Materials
module contains a live viewer and the 3D Viewer and Design Explorer are also linked into the
live netlist.
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21. TRAFFIC SIGNAL CONTROL USING IR SENSORS
6. PROJECT DESCRIPTION
6.1 Circuit Diagram
Fig No. 6.1 Circuit Diagram For Traffic
Circuit diagram description
Above diagram shows circuit diagram of Traffic signal control using IR sensors. In this diagram
switch is provided as a input RC0 to RC3 of PIC microcontroller. We are using two IR module at
appropriate distance on the side of the road to detect the vehicle. The normal traffic has 100ms
delay. If on one side of road there is traffic then the IR sensor give logic high to the PIC
microcontroller. Then the delay of the green LED delay will increase 400ms.
And if the second IR sensors detect vehicles then again the sensors send logic high to the PIC
microcontroller. Then the green LED delay will increase to 800ms.
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22. TRAFFIC SIGNAL CONTROL USING IR SENSORS
If there is no traffic then it will send logic low to the PIC microcontroller. Basically this system
is based on the traffic density.
6.2 Layout
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23. TRAFFIC SIGNAL CONTROL USING IR SENSORS
Fig No. 6.2 Layout
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24. TRAFFIC SIGNAL CONTROL USING IR SENSORS
7. SOFTWARE WORKING
7.2 FLOWCHART
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START
SW1=0 SW2=0
Normal traffic time (100ms)
SW1=! 0
SW2=! 0
SW1=1 SW2=0
Increase Green Time
(400ms)
SW1=1 SW2=1
Increase Green Signal
Time at Max (800ms)

25. TRAFFIC SIGNAL CONTROL USING IR SENSORS
Fig No. 7.1 Flowchart
8. ADVANTAGES AND APPLICATIONS
8.1 Advantages
During normal time the signal timing changes automatically on sensing the traffic density at the
junction but in case of any emergency vehicle like ambulance, fire brigade etc., requiring priority
are built in with RF control to override the set timing by providing instantaneous green signal in
the desired direction while blocking the other lanes by red signal for some time.
It reduces the possibilities of traffic jams caused by traffic lights to an extent.
8.2 Applications
This System Is Very Efficiently Used In Metro Cities.
It will help us to reduce the traffic problems.
It is used to rout the traffic.
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26. TRAFFIC SIGNAL CONTROL USING IR SENSORS
9. CONCLUSIONS AND FUTURE SCOPE
9.1 Conclusions
Integrating features of all the hardware components used have been developed in it. Presence of
every module has been reasoned out and placed carefully, thus contributing to the best working
of the unit. Secondly, using highly advanced IC‘s with the help of growing technology, the
project has been successfully implemented. Thus the project has been successfully designed and
tested.
9.2 Future Scope
We can use GSM module to track location of car.
We can use camera for security purpose.
We can use image processing technique.
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27. TRAFFIC SIGNAL CONTROL USING IR SENSORS
10. LIST OF COMPONENTS AND COSTING
Table No. 10.1
Sr
No
Component Quantity Costing
1. 40*1 Burg Strip 1 5
2. Female to female connector 10 41.25
3. 5 mm led (RGB) 10 10
4. AW 7805 IC 1 9.50
5. In 4007 Diode 4 2
6. 12 MHz Crystal 1 5
7. 14 watt Resistance(1K,2.2K,10K) 13 3.25
8. Copper clad 1 95
9. Capacitor(100uf,22pf,) 4 3.80
10. Tech switch 1 2
11. IR module 2 140
12. PIC184550 1 250
13. Fecl3 2 120
14. IC base 1 10
TOTAL 696.8
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28. TRAFFIC SIGNAL CONTROL USING IR SENSORS
REFERENCES
1. PIC microcontroller. (Author: mazzidi)
2. Ramón Martinez “Smart control system for LEDs traffic-lights based on PLC”. Dpt.
de Senates, Sis-temasy Radio communications. Universidad Po-litécnica de Madrid
ETSI de Telecommunica-tion.Ciudad University s/n.28040 Madrid SPAIN
3. Bechrakis D. A., Sparis P. D.” A flexible data logging device for wind potential
measurements and statistic-al magnitudes”. Democritus university of Thrace,
department of electrical and computer engineering, mechanical engineering
laboratory, xanthi, 67 100, Greece
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29. TRAFFIC SIGNAL CONTROL USING IR SENSORS
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