INTELLIGENT AMBULANCE FOR TRAFFIC CITY AND CONTROL TRAFFIC BASED ON

ITS DENSITY

Faculty of Electronics & Communication Engineering

B.TECH (Electronics & Communication Engineering)

PRIST UNIVERSITYTHANJAVUR

COORDINATOR DEAN

INTELLIGENT AMBULANCE FOR TRAFFIC CITY AND CONTROL TRAFFIC BASED ON

ITS DENSITY

Submitted as partial fulfillment of the requirements for the award of the Degree of Bachelor of Technology in Electronics & Communication

Engineering

Submitted ByAbhishek Kunal 21082210041Ravi Kumar 20182210231Pravin Kumar 21082210200Nawjeet Kumar 21082210171

Under the Guidance ofR.Ramya Devi M.Tech

FACULTY OF ENGINEERING AND TECHNOLOGY

DEPARTMENT OF ELECTRONICS & COMMINICATION ENGINEERING

PRIST UNIVERSITY

THANJAVUR - 613 403.

March – 2012

FACULTY OF ENGINEERING AND TECHNOLOGYDEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING

PRIST UNIVERSITYTHANJAVUR - 613 403.

BONAFIDE CERTIFICATE

This is to certify that the project titled “INTELLIGENT AMBULANCE FOR

TRAFFIC CITY AND CONTROL TRAFFIC BASED ON ITS DENSITY” is a bonafide

record of work done by Abhishek Kunal 21082210041, Ravi Kumar

21082210231 , Pravin Kumar 21082210200 , Nawjeet Kumar

21082210171 in partial fulfilment of the requirements for the award of the

degree of Bachelor of Technology in Electronics & Communication

Engineering of PRIST University, Thanjavur.

Internal Guide Head of the Department

Submitted for the University Viva-Voce examination held on -------------

External Examiner Internal Examiner

ACKNOWLEDGEMENT

The joy and sense of fulfilment that comes along with the successful completion

of any task is complete with the thanking of all those people who made it possible with

their guidance and constant word of encouragement.

We thank our God Almighty for giving us such a excellent facilities and support

through the way of PRIST UNIVERSITY and its Chief Administrator our beloved

Founder & Honorable Chancellor Mr.P.MURUGESAN, for giving us the opportunity

and facilities for completion of this project.

We thank our Vice Chancellor Prof.Dr.N.Ethirajalu, who has always served as a

inspiration for us to perform our institutes name and recognition. We would like to express

our faithful thanks to our Pro Chancellor Prof. Dr.P.S.M Kannan and Dean Prof.

Dr.Willson H.Vincent for having extended all the department facilities without hesitation.

We would like to express our heart-felt gratitude to Associate Dean.

Prof.G.kannan and Head of the Department Prof.A.Rijuvana Begum for the interest

shown by him in this project and for having extended his impartial suggestions

We thank specially MS. R.Ramya Devi, our Internal Guide for giving extremely

valuable guidance and supported us throughout the course of project.

We also thank all the staff members of Electronics and Communication

Engineering Department for their kind cooperation and timely help.

i

SYNOPSIS

Day by day increasing population increases traffic and vehicles also which causes

problems in transportation and management of traffic. Mainly traffic controls at the

crossings required smart traffic signalling system which have high degree of flexibility

according to the flow of traffic in auxiliary roads, on the crossing some roads have a

high density of traffic required rapid release of traffic to maintain the smooth flow of

traffic on busy roads.

In this project we develop a system which sense the traffic density on the particular road

and change the red signal duration accordingly. Here we use IR/Ultrasonic sensors fitted

along the road side to detect the presence of vehicles and change the value of resistance to

change the frequency of the oscillator built around the timer IC which feed to the Johnson

counter and change the cycle rate to control the red/green signals according to the traffic

density. This a simple and effective solution for traffic busy crossings to control

automatically the flow of traffic without disturbing the auxiliary roads.

LIST OF FIGURES

FIGURE NAME PAGE NO.

1.1 Traffic light 1

4.1 Pin Diagram 15

4.2 LCD 19

4.3 Timming Diagram of LCD 21

4.4 Character Display in LCD 22

4.5 Package Dimension Of LED 23

4.6 LED 29

4.7 Micro Vision 33

4.8 D Scope 34

5.1 Model Of Traffic junction 35

5.2 Time Based 36

5.3 Sensor Based 37

6.1 Traffic Control Unit 41

6.2 Microcontroller 43

6.3 Driver Circuit 44

6.4 LCD 45

6.5 LED 46

10.1 Traffic Control Unit 58

10.2 Ambulance Section 59

iii

TABLE OF CONTENTS

TITLE PAGE NO

ACKNOWLEDGEMENT i

SYNOPSIS ii

LIST OF FIGURES iii

CHAPTER 1: INTRODUCTION 1

1.1 Overview of traffic light system 1

1.2 History 2

1.3 Standard 4

1.3.1 European Standard 4

1.3.2 British Standard 4

1.3.3 North American Standard 5

1.3.4 Asian Standard 5

1.4 Technology 51.4.1 Optical and Lightning 5

1.4.2 Programmable Visibility Signals 6

CHAPTER 2: EXISTING SYSTEM 7

2.1 Pre-Timed Controllers 7

2.2 Traffic Acutated 8

CHAPTER 3: PROPOSED SYSTEM 10

3.1 Traffic Control Based on Density 10

3.2 Intelligent Ambulance 11

CHAPTER 4: SOFTWARE AND HARDWARE REQUIREMENTS 12

4.1 Hardware 12

4.1.1 Microcontroller AT89S52 12

4.1.1.1 Architecture 12

4.1.1.2 Instruction Type 13

4.1.1.3 8-Bit Controller 13

4.1.1.4 Features 14

4.1.1.5 Pin Diagram 15

4.1.1.6 Advantages 18

4.1.2 Liquid Crystal Display 19

4.1.2.1 Circuit Diagram 19

4.1.2.2 Circuit Description 20

4.1.3 IR Transmitter 23

4.1.3.1 Output Graphs 24

4.1.3.2 Features 27

4.1.4 IR Receiver 27

4.1.4.1 Diagram 27

4.1.4.2 Features 28

4.1.5 Light Emitting Diode 29

4.1.5.1 Diagram 29

4.1.5.2 Features 30

4.1.6 RF Transmitter & Receiver 31

4.1.6.1 RF Transmitter Receiver 31

4.1.6.2 Special Properties of RF Electrical Signals 31

4.2 Software 32

4.2.1 Keil Cross Compiler 32

4.2.1.1 Features 32

4.2.2 D Scope 33

CHAPTER 5: DATA FLOW DIAGRAM 35

5.1 Traffic Junction Situation 35

5.2 State of Traffic Light 36

5.2.1 Time Based 36

5.2.2 Sensor Based 37

5.3 Traffic Light Simulation Model 38

5.3.1 Time Based 38

5.3.2 Sensor Based 39

CHAPTER 6: MODULES DESCRIPTION 41

6.1 Traffic Control Unit 41

6.1.1 IR Transmitter 41

6.1.2 IR Receiver 42

6.1.3 Microcontroller 42

6.1.4 Driver Circuit 44

6.1.5 Signal Conditioning Unit 45

6.1.6 LCD 45

6.1.7 LED 46

6.2 Ambulance Section 47

6.2.1 Keypad 48

6.2.2 Encoder 48

6.2.3 Transmitter 49

CHAPTER 7: IMPLEMENTATION RESULT 50

CHAPTER 8: CONCLUSION 52

CHAPTER 9: FUTURE ENHANCEMENT 53

9.1 Implementation of GSM 53

9.1.1 GSM 54

9.1.2 Heart Rate Sensor 54

9.1.3 Temperature Sensor 56

9.1.3.1 Feature 56

CHAPTER 10: OUTPUT SCREENSHOT 58

10.1 Traffic Light Control 58

10.2 Ambulance Section 59

CHAPTER 12: REFERENCES 60

1 INTRODUCTION

1.1 OVERVIEW OF TRAFFIC LIGHT SYSTEM

Ever since Roman times, society has tried to control traffic. Even the fabled Roman road

system created a conflict between pedestrian and equine travellers. However, a practical

solution was not developed until the mid-nineteenth century, when J. P. Knight, a railway

signalling engineer, created the first traffic signal, which was installed near Westminster

Abbey in London, England in 1868. Unfortunately, the device exploded, killing a police

officer, and its use was discontinued after being in operation for only a short time.

The modern traffic light was invented in America. New York had a three colour system in

1918 that was operated manually from a tower in the middle of the street. Other cities soon

adopted the idea of having someone on the scene to control the lights. Garrett Morgan,

inventor of the gas mask, also developed traffic signalling devices. Having witnessed an

accident between a car and a carriage, Morgan felt compelled to devise a system to prevent

such collisions at street intersections. In 1923 he patented an electric traffic light system

using a pole with a cross section on which the words STOP and GO were illuminated.

These basic designs were soon improved. In 1926 the first automatic signals were installed

in London; they depended on a timer to activate them. In the 1930s vehicle-activated lights

were created in which cars rolled over half-buried rubber tubes. Air in the tubes was

displaced by the weight of the car rolling over them, and the increased pressure operated an

electric contact, activating the lights. But these tubes wore out quickly. A better idea was

the inductive-loop device: a loop of wire was imbedded in the road itself and connected to

a box controlling the lights; a current of electricity passed through the loop, and when the

steel body of a car passed overhead, it produced a signal that activated the light.

1

Today, traffic is automatically routed onto limited access highways courtesy of a computer

activated guidance system that determines traffic volume on the highway. Global

positioning satellite systems (GPS) are installed in many cars.

These systems connect with a satellite and inform drivers where they are and

possible routes to their destination. Such systems will eventually enable a drive to

determine the best route to a destination given prevailing traffic conditions.

FIGURE 1.1 Traffic Light

1.2 HISTORY

On December 10, 1868, the first traffic lights were installed outside the British Houses of

Parliament in London, by the railway engineer J. P. Knight. They resembled railway

signals of the time, with semaphore arms and red and green gas lamps for night use. The

gas lantern was turned with a lever at its base so that the appropriate light faced traffic. It

exploded on 2 January 1869, injuring or killing the policeman who was operating it.

The modern electric traffic light is an American invention. As early as 1912 in Salt Lake

City, Utah, policeman Lester Wire invented the first red-green electric traffic lights. On

August 5, 1914, the American Traffic Signal Company installed a traffic signal system on

the corner of East 105th Street and Euclid Avenue in Cleveland, Ohio. It had two colours,

red and green, and a buzzer, based on the design of James Hoge, to provide a warning for

colour changes. The designed by James Hoge allowed police and fire stations to control

the signals in case of emergency.

2

The first four-way, three-colour traffic light was created by police officer William Potts in

Detroit, Michigan in 1920. In 1922, T.E. Hayes patented his "Combination traffic guide

and traffic regulating signal" (Patent # 1447659). Ashville, Ohio claims to be the location

of the oldest working traffic light in the United States, used at an intersection of public

roads until 1982 when it was moved to a local museum.

The first interconnected traffic signal system was installed in Salt Lake City in 1917 with

six connected intersections controlled simultaneously from a manual switch. Automatic

control of interconnected traffic lights was introduced March 1922 in Houston, Texas. The

first automatic experimental traffic lights in England were deployed in Wolverhampton in

1927. In 1923, Garrett Morgan patented his own version. The Morgan traffic signal was a

T-shaped pole unit that featured three hand-cranked positions: Stop, go, and an all -

directional stop position. This third position halted traffic in all directions to give drivers

more time to stop before opposing traffic started. Its one "advantage" over others of its

type was the ability to operate it from a distance using a mechanical linkage. Toronto was

the first city to computerize its entire traffic signal system, which it accomplished in 1963.

The colour of the traffic lights representing stop and go might be derived from those used

to identify port (red) and starboard (green) in maritime rules governing right of way, where

the vessel on the left must stop for the one crossing on the right.

Countdown timers on traffic lights were introduced in the 1990s. Though uncommon in

most American urban areas, timers are used in some other Western Hemisphere countries.

Timers are useful for drivers/pedestrians to plan if there is enough time to attempt to cross

the intersection before the light turns red and conversely, the amount of time before the

light turns green.

3

1.3 STANDARDS

1.3.1 EUROPEAN STANDARD

The European approach to a signalized crossing is use dual or more rarely, a triple aspect.

with a blackened out lens of a Pictogram pedestrian. For cyclist, the same approach is used

with the lens blackened out for a bicycle frame. It is not uncommon to see lenses with both

symbols on them.

Green: Cross

Yellow: Continue to cross only if unable to stop safely

Flashing Yellow: Cross with caution, usually used when lights are out of order or

shut down for the night, for low traffic

Red: Do not cross

1.3.2 BRITISH STANDARD

In the United Kingdom, British crown dependencies and dependent territories, and former

possessions like Hong Kong, the light sequence is as follows:

Green: Cross.

Flashing green: Continue to cross only if unable to stop safely.

Red: Do not cross.

The light is blackened out with a pedestrian pictogram.

The same system is used also in Macau, a former Portuguese overseas province near Hong

Kong.

4

1.3.3 NORTH AMERICAN STANDARD

In North America, the most common aspects found are text-only lenses (WALK/DON'T

WALK), the pictogram stop hand (in red/orange) and a walking person (in green or white).

Increasingly for retrofits of dual aspects and newer installations, the lower aspect formerly

used for the "walk" signal (walking person) is being replaced with a timer countdown.

Light sequence:

Green or White (Walking Human or WALK)

Flashing Red/Orange (Stop hand or DON'T WALK)

Red/Orange; Do not cross

1.3.4 ASIAN STANDARD

Green: Cross

Amber: Cross if already in intersection, otherwise do not (however by law, you are

allowed to cross)

Red: Do not cross

1.4 TECHNOLOGY

1.4.1 OPTICS AND LIGHTING

Traditionally, incandescent and halogen bulbs were used. Because of the low efficiency of

light output and a single point of failure (filament burnout) municipalities are increasingly

retrofitting traffic signals with LED arrays that consume less power, have increased light

output, last significantly longer, and in the event of an individual LED failure, still operate

albeit with a reduced light output. With the use of optics, the light pattern of an LED array

can be comparable to the pattern of an incandescent or halogen bulb.

5

Due to the low energy usage aspects of LED lights, these lights can pose a driving risk in

some areas during winter. Incandescent and halogen bulbs are generally warm enough to

melt away snow that cover individual lights but as LED lights use a fraction of the energy

as a result they are not warm enough to melt snow that may overlay the lights during

winter.

1.4.2 PROGRAMMABLE VISIBILITY SIGNALS

Signals such as the 3M High Visibility Signal and McCain Programmable Visibility signal

utilize light-diffusing optics and a powerful fresnel lens to create the signal indication. Lit

via a powerful 150W PAR46 sealed-beam lamp, the light from the lamp in these

"programmable visibility" signals passes through a set of two glass lenses at the back of the

signal. The first lens, a frosted glass diffusing lens, diffuses the light into a uniform ball of

light around five inches in diameter. The light then passes through a nearly identical lens

known as an optical limiter (3M's definition of the lens itself), also known as a

"programming lens", also five inches in diameter.

6

2. EXISTING SYSTEM

Traffic signals alternately assign the right of way to different traffic movements at an

intersection. Vehicular traffic is permitted to flow in a strictly controlled manner. A

controller is used to switch the signal displays. The signal sequence at intersections is red,

green, yellow, and red. The standard period during which a yellow signal is displayed is

fixed at three seconds. The duration of the green signal will depend on the method of

control. It is not recommended the signal sequence cycle be in excess of 120 seconds. Two

basic kinds of controllers are used: Pre-timed and Traffic actuated.

2.1 PRE-TIMED CONTROLLERS

Pre-timed controllers represent traffic control in its most basic form. They operate on a

predetermined, regularly repeated sequence of signal indications. For example, in one

complete phase of the cycle, one street-the primary street-may be assigned 40 seconds of

green time, and the other street may be assigned 15 seconds of green time. Several seconds

per minute are assigned to the yellow, or clearance, interval. The signal rotates through this

defined cycle in a constant fashion, as determined by the controller’s settings. Pre-timed

controllers are best suited for intersections where traffic volumes are predictable, stable,

and fairly constant. They may also be preferable where pedestrian volumes are large and

fairly constant. Depending on the equipment, several timing sequences may be preset to

accommodate variations in traffic volume during the day. The timing of pre-timed signals

is typically determined from visual observations and traffic counts. Once the timing

programs are set, they remain fixed until they are changed manually, in the field.

Generally, pre-timed controllers are cheaper to purchase, install, and maintain than traffic-

actuated controllers.

7

Their repetitive nature facilitates coordination with adjacent signals, and they are useful

where progression is desired. Progression refers to the nonstop movement of vehicles

along a signalized street system. Properly timed signal systems facilitate progression.

2.2 TRAFFIC ACCUTATED

Traffic-actuated controllers differ from pre-timed controllers in that their signal indications

are not of fixed length, but rather change in response to variations in the level and speed of

traffic. Traffic-actuated controllers are typically used where traffic volumes fluctuate

irregularly or where it is desirable to minimize interruptions to traffic flow on the street

carrying the greater volume of traffic. A simple traffic-actuated signal installation consists

of four basic components: detectors, the controller unit, signal heads (the traffic lights), and

connecting cables. The detectors are usually placed in the pavement, but they are

sometimes positioned on signal poles. Commonly used types include the inductive loop

detector, magnetic detector, magnetometer, and microwave detector. The inductive loop

detector is by far the most common. A loop of metal wire is embedded in a saw-cut slot in

the pavement and then covered with a protective epoxy sealant. As a vehicle travels over

the detector, its metallic mass changes the inductance of the loop. The detector processes

this change and notifies the controller unit of the presence of a vehicle. There are three

basic types of traffic actuated controllers: Semi-actuated controllers, fully actuated

controllers, and volume-density controllers.

Semi-actuated controllers assign a continuous green indication to the major street except

when a detector signals that a vehicle on the minor street is waiting to enter the

intersection. Traffic detectors are thus only needed on the minor street approaches. If a

vehicle is detected on the minor street, a demand for a green is registered and stored in the

controller unit. Once a green signal is displayed on the minor street, the duration may be

extended by vehicles detected moving towards the signal to a preset maximum period after

the demand has been received.

8

On expiry of the last extension and with no more vehicles detected, the minor street lights

transition from green to yellow to red, allowing the major street lights to return to green.

Even if vehicles are waiting to cross the major street, the major street should remain green

for a preset minimum period after returning to green.

Fully actuated controllers require detectors on all lanes approaching an intersection. They

are most useful when vehicle volumes vary over the course of the day, making frequent

timing changes necessary. Fully actuated controllers are often preferred because of their

responsiveness to actual traffic conditions.

Volume-density controllers are a more advanced type of fully actuated controllers. They

record and retain actual traffic information, such as volumes. Using the recorded

information, they can calculate-and recalculate as necessary-the duration of the minimum

green time based on actual traffic demand. The efficiency of a traffic-actuated signal

installation depends on the programming of the unit

and the location of the detectors.

Another type of actuated control uses a computer to control, operate, and supervise a traffic

control signal system. Computer-controlled systems basically consist of a central

computer, communication media (cable, telephone, radio, etc.), and field equipment (local

controllers, detectors, etc.). Both pre-timed control and actuated control have application

today. In Howard County, Maryland, for example, pre-timed controllers are used to

coordinate the flow of traffic on main streets during the day, with semi-actuated control on

minor streets. At night, when traffic volumes drop, fully actuated control is used on all

streets.

Timing adjustments should be made by trained technicians and should be based on the

traffic periods. When adjusting a controller, the technician should observe the effect on

traffic and then fine-tune the settings as necessary. Intersections should be periodically

monitored to ensure the signals are operating efficiently. As traffic volumes and other

conditions change, the controller settings will need to be changed accordingly.

9

3 PROPOSED SYSTEM

3.1 TRAFFIC CONTROL BASED ON DENSITY

In this system IR sensors are used to measure the density of the vehicles which are

fixed with in a fixed distance. All the sensors are interfaced with the microcontroller

which in turn controls the traffic signal system according to density by the sensor.

If the traffic density is high in particular side more priority is given for that side. The

sensor continuously keeps sensing density on all sides and the green signal is given to

the side in priority basis, where the sensor detects high density. The side with next

priority level follows the first priority level.

By using this system traffic can cleared without irregularities and time delays even

though there is no traffic on the other side can be avoided.

3.1.1 DESCRIPTION

We have three pairs of sensors across the roads marking as low, medium and high

density zones respectively.

There will be a infrared transmitter and infrared receiver opposite to each other .

We will place sensors at some distance apart from another pair.

When vehicles are filled and cross the first pair of sensors , then there will be an

obstacle between transmitter and receiver and this lead to a digital signal (low or

high) and the microcontroller assumes that there is low density traffic

When the vehicle crosses second sensor ten it assumes medium density and for

third sensor pair high density traffic respectively.

Depending on the above process a digital data is sent to microcontroller whether

it’s low or high and the microcontroller will allot the time for the traffic to pass on.

10

For high density traffic there will be more allotment of the time and for low density

low time respectively. Program written to the microcontroller will make it to do the

operation.

So the microcontroller will send its timing signal output by comparing with the

adjacent road’s traffic.

3.2 INTELLIGENT AMBULANCE

Most of the time the traffic will be at least for 100meters .In this distance the traffics

police can’t hear the siren form the ambulance. Then the ambulance has to wait till the

traffic is cleared. Some times to free the traffic it takes at least 30 minutes .So by this time

anything can happen to the patient .So this project avoid these disadvantages. The second

feature is the information system in the Ambulance. The system will inform the status of

the patient to the hospital as the command giving to the system in the ambulance.

According to this project if any ambulance at emergency comes to any traffic post the

traffic signals automatically stop the signals and give green signal for this ambulance.

Normally, we will have the traffic signal lights programmed for a particular time intervals.

But, here we will generate the traffic light signals based on the traffic, on the particular

time.

3.2.1 DESCRIPTION

When the ambulance at emergency comes to any traffic post the traffic signals

automatically stop the signals and give green signal for this ambulance.

The ambulance carries an IR transmitter and IR receiver will be there at few meters

at the signal. The receiver will receive the signal and the module will send the

command to turn on green through the RF and every traffic post will have an RF

receiver. So whenever the ambulance comes near the traffic, the ambulance will

transmit a code say “emergency” the receiver will receive this signal .Then it

immediately switch off the other signals i.e. it make all the signals red and later

make way for ambulance by signalling green. So by doing this the ambulance can

go without any problem.

11

4 SOFTWARE AND HARDWARE REQUIREMENT

4.1 HARDWARE

4.1.1 MICROCONTROLLER AT89S52

A microcontroller is an integrated chip that is often part of an embedded system. The

microcontroller includes a CPU, RAM, ROM,I/O ports, and timers like a standard

computer, but because they are designed to execute only a single specific task to

control a single system ,they are much smaller and simplified.

4.1.1.1 ARCHITECTURE

Architecture of Microcontroller is classified into two types: Data Flow and Instruction.

Data Flow

There are two types of architecture in data flow. They are :

Von Neumann Architecture

Harvard Architecture

One shared memory is only available for instructions (program) and data

instructions and data have to be fetched in sequential order in case of Von Neumann

architecture. The Harvard architecture on the other hand uses physically separate

memories for their instructions and data, requiring dedicated buses for each of them.

Instructions and Operands can therefore be fetched simultaneously.

12

4.1.1.2 INSTRUCTION TYPE

There are two types of architecture in instruction type. They are

CISC

RISC

CISC

CISC architecture supports as many as 200 instructions. A CISC microprocessor

contains a more complex set of instructions that it responds to and some of these

instructions cannot be completed in one machine cycle

RISC

This is a type of architecture that recognizes a relatively limited number of

instructions. Until the mid-1980s, the tendency among computer manufacturers was to

build increasingly complex CPUs that had ever-larger sets of instructions . At that time,

however, a number of computer manufacturers decided to reverse this trend by

building CPUs capable of executing only a very limited set of instructions. One

advantage of reduced instruction set computers is that they can execute their

instructions very fast because the instructions are so simple.

4.1.1.3 8 BIT- CONTROLLER

Application volumes for the 8-bit microcontrollers may be as high as the 4-bit

models, or they may be very low. Application sophistication can also range from

simple application control to high-speed machine control and data collection. For these

reasons, the microcontroller vendors have established extensive “families “of similar

models.

13

All features a common language, but differ in the amount of internal ROM, RAM, and

other cost-sensitive features. Often the memory can be expanded to include off-chip

ROM and RAM; in some cases, the microcontroller has no on-board ROM at all, or the

ROM is an electrically reprogrammable read only memory (EPROM).

Manufacture: Intel 8051

Pins/I/O : 40/32

Counter : 2

RAM : 256bytes

ROM : 8K

4.1.1.4 FEATURES OF AT89S52

8 bit Microcontroller

8K bytes of Flash Programmable and Erasable ROM

Fully Static Operation: 0 Hz to 24 MHz

256* 8-bit Internal RAM

32 Programmable I/O Lines

Six Interrupt Sources

Two 16 bit Timer/Counters

Programmable Serial Channel

Low Power Idle and Power-down modes

Three level Program Memory Lock

14

4.1.1.5 PIN DIAGRAM AND DESCRIPTION

PIN DIAGRAM

FIGURE-4.1 Pin Diagram

PIN DESCRIPTION

VCC: Supply Voltage (Pin 40)

GND: Ground (Pin 20)

Port 0:

It occupies a total of 8 pins (32-39) which can be used as both input and

output. To use the pins of port 0 as both input and output ports, each pin must be

connected externally to a 10KΩ pull-up resistor .

15

This is due to the fact that P0 is an open drain, unlike P1,P2,P3. When 1s are written to

port 0 pins, they can be used as high impedance inputs. Port 0 may also be configured

to be a multiplexed low order address/data bus during accesses to external program and

data memory. It receives code bytes during flash programming.

Port 1:

It occupies a total of 8 pins(1-8). It is bidirectional port with internal pull ups.

When 1’s are written to port 1, they can be used as inputs. It receives low order address

bytes during flash programming and verification.

Port 2:

It occupies a total of 8 pins (21-28). It is a bidirectional port with internal pull

ups. When 1s are written to port 1, they can be used as inputs. It emits higher order

address bytes during fetches from external program memory and during accesses to

external data memory that uses 16 bit address. It receives higher order address bits and

control signals during flash programming and verification.

Port 3:

It occupies a total of 8 pins (10-17). It is a bidirectional port with internal pull

ups.When 1s are written to port 3, they are used as inputs. It also receives control

signals during flash programming and verification. Port 3 has the additional function of

providing some extremely important signals such as interrupts. P3.0 and P3.1 are used

for RxD and TxD serial communication signals. Bits 3.2 and 3.3 are set for external

interrupts. Bits 3.3 and 3.4 are used for timers 0 and 1. Pins 3.6 and 3.7 are used to

provide the read and write signals( active- low) of external memories.

16

TABLE-1- Pin details of Port 3

RST :

Reset Input (Pin 9). A high on this pin (normally low) for two machine cycles

while the oscillator is running resets the device. This is often referred to as Power-On

reset. Activating a power-on reset will cause all values in the registers to be lost. It will

set Program Counter to all 0s.

XTAL1:

Input to the inverting oscillator amplifier and input to the internal clock

operating circuit. (Pin 19)

17

XTAL2:

Output from the inverting oscillator amplifier (Pin 20).

ALE/PROG:

Address Latch Enable output pulse (Pin 30) for latching the low byte of

the address during accesses to external memory. This pin is also the program pulse

input (PROG) during flash programming.

PSEN:

Program Store Enable is the read strobe to external program memory (Pin 29).

EA/VPP:

External Access Enable (Pin 31). EA must be strapped to ground in order to

enable the device to fetch code from external program memory locations. EA should be

strapped to VCC for internal program executions. It also receives the 12V

programming enable voltage during flash programming.

4.1.1.6 ADVANTAGES OF AT89S52

Cost effective

Low Power

Highly flexible

High performance

18

4.1.2 LCD (LIQUID CRYSTAL DISPLAY)

A liquid crystal display (LCD) is a thin, flat display device made up of any number of color or

monochrome pixels arrayed in front of a light source or reflector. It is utilized in battery-

powered electronic devices as it uses very small amounts of electric power. LCDs with a small

number of segments, such as those used in digital watches and pocket calculators have

individual electrical contacts for each segment. An external dedicated circuit supplies an

electric charge to control each segment.

FIGURE 4.2 LCD

4.1.2.1 CIRCUIT DIAGRAM

Figure 4.3 A 16 Character x 2 Line LCD Module

19

4.1.2.2 CIRCUIT DISCRIPTION

The LCD panel's Enable and Register Select is connected to the Control Port. The

Control Port is an open collector / open drain output. By incorporating two 10K

external pull up resistors, the circuit is made portable for a wider range of computers.

The R/W line of the LCD panel is hard-wired into the write mode which will not cause

any bus conflicts on the data lines. Hence the LCD's internal Busy Flag cannot tell if

the LCD has accepted and finished processing the last instruction or not. The 10k

Potentiometer controls the contrast of the LCD panel

1GND Ground

2 VCC Supply Voltage +5V

3 VEE Contrast adjustment

4 RSRegister select :0->Control input,

1-> Data input

5 R/W Read/ Write

6 E Enable

7 to 14 D0 to D7 I/O Data pins

15 VB1 Backlight +5V

16 VB0 Backlight ground

20

Table 2 Pin Details of LCD

Figure 4.3 Timing diagram of LCD

This waveform will write an ASCII Byte out to the LCD's screen. The ASCII code to

be displayed is eight bits long and is sent to the LCD either four or eight bits at a time.

If four bit mode is used, two "nibbles" of data (Sent high four bits and then low four

bits with an "E" Clock pulse with each nibble) are sent to make up a full eight bit

transfer. The "E" Clock is used to initiate the data transfer within the LCD.

The "R/S" bit is used to select whether data or an instruction is being transferred

between the microcontroller and the LCD. If the Bit is set, then the byte at the current

LCD "Cursor" Position can be read or written. When the Bit is reset, either an

instruction is being sent to the LCD or the execution status of the last instruction is read

back Reading Data back is used in applications which requires data to be moved back

and forth on the LCD .

The "Busy Flag" can be polled to determine when the last instruction that has been sent

has completed processing. The "R/W" line is tied to ground if read back is not required.

This simplifies the application because when data is read back, the microcontroller I/O

pins have to be alternated between input and output modes. The "Clear Display" and

"Return Cursor and LCD to Home Position" instructions are used to reset the Cursor's

position to the top right character on the display.

21

Figure 4.4

Character display in LCD

Eight programmable characters are available and use codes 0x000 to 0x007. They are

programmed by pointing the LCD's "Cursor" to the Character Generator RAM

("CGRAM") Area at eight times the character address. The next eight characters

written to the RAM are each line of the programmable character, starting at the top.

Each LCD character is actually eight pixels high, with the bottom row normally used

for the underscore cursor. The bottom row can be used for graphic characters. The user

defined character line information is saved in the LCD's "CGRAM" area. This sixty

four bytes of memory is accessed using the "Move Cursor into CGRAM" instruction.

A potentiometer wired as a voltage divider is used as a contrast voltage to the Display.

This will provide an easily variable voltage between Ground and Vcc, which will be

used to specify the contrast (or "darkness") of the characters on the LCD screen.

Different LCDs work differently with lower voltages providing darker characters in

some and higher voltages do the same thing in others.

There are a variety of different ways of wiring up an LCD. To simplify the demands in

microcontrollers, a shift register is often used to reduce the number of I/O pins to three.

22

4.1.3 IR TRANSMITTER

A IR TRANSMITTER device consists of a timer circuit connected to an infrared

LED array. The timer causes the infrared LEDs to strobe at specific frequencies,

such as 10Hz for low priority (buses) or 14 Hz for high priority (emergency

vehicles). Low Priority transmitters will control the intersection to perform a

normal light change, while High Priority transmitters will change an entire

intersection immediately

Figure 4.5 Package Dimension

23

ABSOLUTE MAXIMUM RATINGS (TA = 25°C unless otherwise specified)

Parameter Symbol Rating Unit

Operating Temperature TOPR -40 to +100 °C

Storage Temperature TSTG -40 to +100 °C

Soldering Temperature (Iron) TSOL-I 240 for 5 sec °C

Soldering Temperature (Flow) TSOL-F

260 for 10 sec °C

Continuous Forward Current IF 100 mA

Reverse Voltage VR 5 V

Power Dissipation (1) PD 200 mWPeak Forward Current (5) IF(Peak) 1.5 A

4.1.3.1 OUTPUT GRAPHS:

1. Normalized Radiant Intensity vs. Input Current

24

2 Forward Voltage vs. Temperature

4 Normalized Radiant Intensity vs. Wavelength

25

5 Forward Current vs. Forward Voltage

6 Radiation Pattern

26

4.1.3.2 FEATURES

Wavelength= 880 nm

Chip material = AlGaAs

Package type: T-1 3/4 (5mm lens diameter)

Matched Photo sensor: QSD122/123/124

Medium Wide Emission Angle, 40°

High Output Power

Package material and color: Clear, purple tinted, plastic

4.1.4 IR RECEIVER

4.1.4.1 DIAGRAM

Narrow response range (660 nm peak),single heterostructure on the substrate

Spectral range Type Technology Case

Visible-red EPD-660-5 AlGaAs/AlGaAs/GaAs 5 mm plastic lens

27

Maximum Ratings

Parameter Value Unit

Storage Temperature - 40...+90 °C

Operating Temperature -40...+85 °C

Soldering Temperature 240 °C

Table-

Optical and Electrical Characteristics (Tamb = 25°C, unless otherwise specified)

Parameter Test conditions Symbol Min Typ Max Unit

Active area A 0.13 mm2

Peak sensitivity Smax 620 660 700 nm

Spectral bandwidth at 50% Ä 0,5 25 nm

Acceptance angle at 50% Së 40 deg.

Responsivity at 660 nm VR = 0 V Së 0.42 A/W

Short-circuit current* VR = 0, Ee=1 mW/cm²

ISC 0.85 µA

Dark current VR = 5 V, Ee=0 ID 40 200 pA

Reverse voltage IR = 10 µA VR 10 V

Junction capacitance VR = 0, Ee=0 Ñ 40 pF

Rise time

Fall time

RL = 50 ,

VR = 5 V

trtf

15

30ns

Table-

4.1.4.2 FEATURES Photo detector and preamplifier in one package

Internal filter for PCM frequency

Improved shielding against electrical field disturbance

TTL and CMOS compatibility

Output active low

Low power consumption

High immunity against ambient light

28

4.1.5 LED (LIGHT EMITTING DIODE)

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

usually small in area (less than 1 mm2), and integrated optical components are used to

shape its radiation pattern and assist in reflection. 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. LEDs

powerful enough for room lighting are relatively expensive and require more precise

current and heat management than compact fluorescent lamp sources of comparable

output.

FIGURE 4.6 LED

29 FEATURES

Efficiency: LEDs emit more light per watt than incandescent light bulbs. Their

efficiency is not affected by shape and size, unlike fluorescent light bulbs or tubes.

Colour: LEDs can emit light of an intended colour without using any colour filters as

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

Size: LEDs can be very small (smaller than 2 mm) and are easily populated onto

printed circuit boards.

On/Off time: LEDs light up very quickly. A typical red indicator LED will achieve

full brightness in under a microsecond LEDs used in communications devices can

have even faster response times.

Cycling: LEDs are ideal for uses subject to frequent on-off cycling, unlike fluorescent

lamps that fail faster when cycled often, or HID lamps that require a long time before

restarting.

Dimming: LEDs can very easily be dimmed either by pulse-width modulation or

lowering the forward current.

Cool light: In contrast to most light sources, LEDs radiate very little heat in the form

of IR that can cause damage to sensitive objects or fabrics. Wasted energy is dispersed

as heat through the base of the LED.

Slow failure: LEDs mostly fail by dimming over time, rather than the abrupt failure of

incandescent bulbs.

Lifetime: 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

tubes typically are rated at about 10,000 to 15,000 hours, depending partly on the

conditions of use, and incandescent light bulbs at 1,000–2,000 hours.

Shock resistance: LEDs, being solid state components, are difficult to damage with

external shock, unlike fluorescent and incandescent bulbs, which are fragile.

Focus: 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

30

4.1.6 RF TRANSMITTER RECEIVER

Radio frequency (RF) radiation is a subset of electromagnetic radiation with a

wavelength of 100km to 1mm, which is a frequency of 3 KHz to 300 GHz,[1]

respectively. This range of electromagnetic radiation constitutes the radio spectrum

and corresponds to the frequency of alternating current electrical signals used to

produce and detect radio waves. RF can refer to electromagnetic oscillations in

either electrical circuits or radiation through air and space. Like other subsets of

electromagnetic radiation, RF travels at the speed of light.

4.1.6.1 Radio communication

In order to receive radio signals, for instance from AM/FM radio stations, a

radio antenna must be used. However, since the antenna will pick up thousands of

radio signals at a time, a radio tuner is necessary to tune in to a particular

frequency (or frequency range).[2] This is typically done via a resonator (in its

simplest form, a circuit with a capacitor and an inductor). The resonator is

configured to resonate at a particular frequency (or frequency band), thus

amplifying sine waves at that radio frequency, while ignoring other sine waves.

Usually, either the inductor or the capacitor of the resonator is adjustable, allowing

the user to change the frequency at which it resonates.

4.1.6.2 Special properties of RF electrical signals

Electrical currents that oscillate at RF have special properties not shared by

direct current signals. One such property is the ease with which they can ionize air

to create a conductive path through air. This property is exploited by 'high

frequency' units used in electric arc welding, although strictly speaking these

machines do not typically employ frequencies within the HF band. Another special

property is an electromagnetic force that drives the RF current to the surface of

conductors, known as the skin effect.

31

4.2 SOFTWARE

4.2.1 KEIL CROSS COMPILER

A KEIL cross compiler is a software, which compiles a source code of one

environment as an object file to be executed in different environment.

It is broadly classified into development and simulation.Development of programs

are handled by Micro vision software and the simulation is handled by D Scope.

The Keil C51 C Compiler for the 8051 microcontroller is the most popular 8051 C

compiler in the world. It provides more features than any other 8051 C compiler

available today.

The C51 Compiler allows you to write 8051 microcontroller applications in C that,

once compiled, have the efficiency and speed of assembly language. Language

extensions in the C51 Compiler give you full access to all resources of the 8051.

The C51 Compiler translates C source files into relocatable object modules which

contain full symbolic information for debugging with the µVision Debugger or an

in-circuit emulator. In addition to the object file, the compiler generates a listing

file which may optionally include symbol table and cross reference information.

4.2.1.1-FEATURE

To help expedite the software development process, µVision offers numerous

features like:

A pull down menu system,

·Multiple file editing capability,

Full function editor with colour syntax highlighting, user definable key

sequences, and editor functions,

Application manager for accessing external programs,

Project manager and automated make facility for building target files,

32

The programs are typed in µVision and compiled here. The below is the screen of µVision

with a sample program.

Figure 4.7 - MICRO VISION

4.2.2 D SCOPE

DScope is a software debugger which simulates the hardware of the MCS 51, MCS

251 and 80C166 microcontroller family and can execute all machine instructions.

Simulation of the integrated peripherals is implemented by means of loadable

drivers. This makes DScope fully capable of simulating the integrated hardware of

the various derivatives of the microcontrollers. A corresponding driver exists for

each controller type supported. The software test is executed optionally either at the

source level, assembler level, or a combination of both.

33

All the actions that are performed by the program can be simulated here.

The values can be assigned to any of the ports and the output can be viewed. And

any peripherals that have to be used can be selected from the menu. In the picture

below the debugging window and the windows corresponding to the input/output

ports are displayed.

Figure 4.8- D SCOPE

34

5 DATA FLOW DIAGRAM

5.1 TRAFFIC JUNCTION SITUATION

Figure 5.1 Model of the traffic junction situation

DESCRIPTION

There were two sets of data that has been analyzed: data from time-based system and the

sensor-based system. These data obtained from the reports generated by Arena after the

entire simulation full. They were analyzed to see if the improvement in waiting time of

vehicle is succeeded or not. The data is compared by using the paired T -test, a way to

compare two sets of data to see if significant improvement has been made or not.

35

The paired T-test of the data acquired from the simulation is done in two tests: the paired

T-test of the data from the simulation in normal traffic condition and the paired T -test of

the data from the simulation of busy traffic condition. As the simulation generates vehicles

in random arrival time based on exponential distribution, average waiting time is different

in different simulation run.

5.2 STATE OF TRAFFIC LIGHT

5.2.1 TIME BASED

Figure 5.2 Time Based

36

5.2.2 SENSOR BASED

Figure 13

5.3TRAFFIC LIGHT SIMULATION MODEL

5.3.1 TIME BASED

37

5.3.1 SENSOR BASED

DESCRIPTION

The above Data Flow Diagram show the simulation models for time based and sensor-

based during run. Simulation has been run for 200 seconds for 25 run for each .time-based

and sensor-based system in normal and busy condition. Data from the reports generated in

Arena is mean waiting compiled in Microsoft Excel before the paired T –test is done using

Microsoft Excel. Figure shows the time (in seconds) of time-based system and sensor-

based system in normal and busy condition.

All statistical data from simulation and paired T -test is compiled in Table . From here, t-

value is calculated at 10.087 for normal traffic condition and 4.5115 for busy traffic

condition. With t-value as calculated and degree of freedom is 24 (n-l), the p-value for

normal traffic condition is 4.l495TIO, whereas the p-value for busy traffic condition is

1.438y4. As both p-value is less than 0.05, it is safe to assume that there are different

values in both normal and busy condition, which suggests there are improvements if the

sensor is implemented in the system.

38

Result of the study from simulation modelling of the traffic light control system with time-

based system and the sensor-based system showed that there are a lot of improvements on

waiting time of vehicles in the junctions if the implementation of sensor is done to the

traffic light\ system. Mean waiting time of time-based traffic light system is around 20

seconds for both normal traffic condition and busy traffic condition, while for sensor-based

traffic light system, the mean waiting time for vehicles in the junctions is about 7.5

seconds for normal traffic condition, and about 17 seconds for busy traffic conditions.

Within this study, the Arena simulation software, which is more appropriate for simulation

of manufacturing system, is used. While there are a lot of specific tools or simulation

software intended for traffic light studies available, the Arena software proves to be more

general purpose simulation software that can be used in simulation of the traffic light

control system. Therefore, in formulating optimal solutions for each of the traffic light in

the intersections, more appropriate tools can be used to study the traffic light system and to

improve the traffic condition at the intersection intended. However, some of the tools used

in studying the traffic light system are intended for specific purpose of the study or scarce

and hard to get. Hence a more general purpose tool such as Arena simulation software can

be configured in order to get the optimal solutions for the intended studies.

TABLE

39

Traffic light control system involves a very complex study. Even implementing one traffic

light in a single junction involved a lot of studies to be done and there is no obvious

optimal solution. In the study there are four junctions of an intersection involved, therefore,

a more complex work needs to be done as the state of one light influences the traffic flow

and conditions of other junctions as well.

While the work is to see if the implementation of sensor in the traffic light control system

can improve the waiting time of vehicles in the junction of an intersection, it does not

provide an optimal solution for the improvement of the waiting time of vehicles in

junctions as each parameter of the traffic light system such as arrival rate of vehicles at the

intersection, the average number of vehicles waiting in the junction and optimal traffic

light duration is different from one intersection to another. These parameters need to be

studied first to obtain the optimal solutions for the intended traffic light system. However,

the simulation done within the study provided general solution for implementing sensors in

the traffic light control system. Therefore, by implementing sensor in traffic light system,

the waiting time for vehicles in the junctions at the intersection can be reduced

significantly as has been proven by statistical method. Further improvements can be made

in the system by modifying the parameters in the simulation suitable for intended studies.

40

6. MODULES DESCRIPTION

6.1TRAFFIC CONTROL UNIT

This section consists of microcontroller, LCD display

FIGURE 6.1 Traffic Control Unit

6.1.1 IR TRANSMITTER

Infrared (IR) transmitters are found in many everyday electronic devices, such as

television remote controls. These devices operate in the electromagnetic spectrum's

infrared region. An IR transmitter is designed to transmit signals and commands to

electronic equipment through infrared waves.

41

Infrared transmitters are short-range communication devices and are not designed for

long-range communication.

An IR transmitter can be employed for many applications. Essentially, it is used to give

commands to electronic devices from a distance without using cords, cables or wires.

Most modern electronic devices are controlled mainly through an IR transmitter,

making them remote-control devices. Very few designated buttons make it onto actual

modern electronics such as televisions and video game systems

6.1.2 IR RECIEVER

IR receiver controls are using a 32-56 kHz modulated square wave for communication.

These circuits are used to transmit a 1-4 kHz digital signal (OOK modulation) through

infra light (this is the maximum attainable speed, 1000-4000 bits per sec). The

transmitter oscillator runs with adjustable frequency in the 32-56kHz range, and is

being turned ON/OFF with the modulating signal, a TTL voltage on the MOD input.

On the receiver side a photodiode takes up the signal. The integrated circuit inside the

chip is sensitive only around a specified frequency in the 32-56 kHz range. The output

is the demodulated digital input (but usually inverted), just what we used to drive the

transmitter. When the carrier is present, this output is usually low. When no carrier is

detected, the output is usually high.

6.1.3 MICROCONTROLLER

A microcontroller (sometimes abbreviated µC, uC or MCU) is a small computer on a

single integrated circuit containing a processor core, memory, and programmable

input/output peripherals. Program memory in the form of NOR flash or OTP ROM is also

often included on chip, as well as a typically small amount of RAM.

42

Microcontrollers are designed for embedded applications, in contrast to the

microprocessors used in personal computers or other general purpose applications.

Microcontrollers are used in automatically controlled products and devices, such as

automobile engine control systems, implantable medical devices, remote controls, office

machines, appliances, power tools, toys and other embedded systems. By reducing the size

and cost compared to a design that uses a separate microprocessor, memory, and

input/output devices, microcontrollers make it economical to digitally control even more

devices and processes. Mixed signal microcontrollers are common, integrating analog

components needed to control non-digital electronic systems.

FIGURE 6.2 MICROCONTROLLER

Some microcontrollers may use four-bit words and operate at clock rate frequencies as low

as 4 kHz, for low power consumption (milli watts or microwatts). They will generally have

the ability to retain functionality while waiting for an event such as a button press or other

interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be

just nano watts, making many of them well suited for long lasting battery applications.

Other microcontrollers may serve performance-critical roles, where they may need to act

more like a digital signal processor (DSP), with higher clock speeds and power

consumption.

43

6.1.4 DRIVER CIRCUIT

In electronics, a driver is an electrical circuit or other electronic component used to control

another circuit or other component, such as a high-power transistor. They are usually used

to regulate current flowing through a circuit or is used to control the other factors such as

other components, some devices in the circuit. The term is used, for example, for a

specialized computer chip that controls the high-power transistors in AC-to-DC voltage

converters. An amplifier can also be considered the driver for loudspeakers, or a constant

voltage circuit that keeps an attached component operating within a broad range of input

voltages.

FIGURE 6.2 DRIVER

CIRCUIT

Typically the driver stage(s) of a circuit requires different characteristics to other circuit

stages. For example in a transistor power amplifier, typically the driver circuit requires

current gain, often the ability to discharge the following transistor bases rapidly, and low

output impedance to avoid or minimise distortion.

44

6.1.5 SIGNAL CONDIONING CIRCUIT

In electronics, signal conditioning means manipulating an analog signal in such a way that

it meets the requirements of the next stage for further processing. Most common use is in

analog-to-digital converters.

In control engineering applications, it is common to have a sensing stage (which consists

of a sensor), a signal conditioning stage (where usually amplification of the signal is done)

and a processing stage (normally carried out by an ADC and a micro-controller).

Operational amplifiers (op-amps) are commonly employed to carry out the amplification of

the signal in the signal conditioning stage.

Signal inputs accepted by signal conditioners include DC voltage and current, AC voltage

and current, frequency and electric charge. Sensor inputs can be accelerometer,

thermocouple, thermistor, resistance thermometer, strain gauge or bridge, and LVDT or

RVDT. Specialized inputs include encoder, counter or tachometer, timer or clock, relay or

switch, and other specialized inputs. Outputs for signal conditioning equipment can be

voltage, current, frequency, timer or counter, relay, resistance or potentiometer, and other

specialized outputs.

Signal conditioning can include amplification, filtering, converting, range matching,

isolation and any other processes required to make sensor output suitable for processing

after conditioning.

6.1.6 LCD

A liquid crystal display (LCD) is a flat panel display, electronic visual display, or video

display that uses the light modulating properties of liquid crystals (LCs). LCs do not emit

light directly.

45

LCDs are used in a wide range of applications, including computer monitors, television,

instrument panels, aircraft cockpit displays, signage, etc. They are common in consumer

devices such as video players, gaming devices, clocks, watches, calculators, and

telephones. LCDs have replaced cathode ray tube (CRT) displays in most applications.

They are available in a wider range of screen sizes than CRT and plasma displays, and

since they do not use phosphors, they cannot suffer image burn-in. LCDs are, however,

susceptible to image persistence.

FIGURE 6.4 LCD

LCDs are more energy efficient and offer safer disposal than CRTs. Its low electrical

power consumption enables it to be used in battery-powered electronic equipment. It is an

electronically modulated optical device made up of any number of segments filled with

liquid crystals and arrayed in front of a light source (backlight) or reflector to produce

images in colour or monochrome. The most flexible ones use an array of small pixels. The

earliest discovery leading to the development of LCD technology, the discovery of liquid

crystals, dates from 1888. By 2008, worldwide sales of televisions with LCD screens had

surpassed the sale of CRT units.

6.1.7 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 other 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.

46

FIGURE 6.5 LED

When a light-emitting diode is forward-biased (switched on), electrons are able to

recombine with electron holes within the device, releasing energy in the form of photons.

This effect is called electroluminescence and the color of the light (corresponding to the

energy of the photon) is determined by the energy gap of the semiconductor. LEDs are

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,

and faster switching. LEDs powerful enough for room lighting are relatively expensive and

require more precise current and heat management than compact fluorescent lamp sources

of comparable output. Light-emitting diodes are used in applications as diverse as aviation

lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have

allowed new text, video displays, and sensors to be developed, while their high switching

rates are also useful in advanced communications technology. Infrared LEDs are also used

in the remote control units of many commercial products including televisions, DVD

players, and other domestic appliances.

6.2AMBULANCE SECTION

47

6.2.1 KEYPAD

A keypad is a set of buttons arranged in a block or "pad" which usually bear digits,

symbols and usually a complete set of alphabetical letters. If it mostly contains numbers

then it can also be called a numeric keypad. Keypads are found on many alphanumeric

keyboards and on other devices such as calculators, push-button telephones, combination

locks, and digital door locks, which require mainly numeric input.

As a general rule, the keys on calculator-style keypads are arranged such that 123 is on the

bottom row. Whereas, in a telephone keypad, either in a home or mobile phone, there will

be the 123-keys at the top. A phone key-pad also has the special buttons labelled * (star)

and # (octothorpe, number sign, "pound" or "hash") on either side of the zero key. Most of

the keys on a telephone also bear letters which have had several auxiliary uses, such as

remembering area codes or whole telephone numbers.

The keypad of a calculator contains the digits 0 through 9, from bottom upwards, together

with the four arithmetic operations, the decimal point and other more advanced

mathematical functions.

Keypads are also a feature of some combination locks. This type of lock is often used on

doors, such as that found at the main entrance to some offices.

6.2.1 ENCODER

An encoder is a device, circuit, transducer, software program, algorithm or person that

converts information from one format or code to another, for the purposes of

standardization, speed, secrecy, security, or saving space by shrinking size.

48

6.2.2 TRANSMITTER

In electronics and telecommunications a transmitter or radio transmitter is an electronic

device which, with the aid of an antenna, produces radio waves. The transmitter itself

generates a radio frequency alternating current, which is applied to the antenna. When

excited by this alternating current, the antenna radiates radio waves. In addition to their use

in broadcasting, transmitters are necessary component parts of many electronic devices that

communicate by radio, such as cell phones, wireless computer networks, Bluetooth

enabled devices, garage door openers, two-way radios in aircraft, ships, and spacecraft,

radar sets, and navigational beacons. The term transmitter is usually limited to equipment

that generates radio waves for communication purposes; or radiolocation, such as radar and

navigational transmitters. Generators of radio waves for heating or industrial purposes,

such as microwave ovens or diathermy equipment, are not usually called transmitters even

though they often have similar circuits. The term is popularly used more specifically to

refer to transmitting equipment used for broadcasting, as in radio transmitter or television

transmitter. This usage usually includes both the transmitter proper as described above,

and the antenna, and often the building it is housed in.

An unrelated use of the term is in industrial process control, where a "transmitter" is a

telemetry device which converts measurements from a sensor into a signal, and sends it,

usually via wires, to be received by some display or control device located a distance

away.

49

7 IMPLEMENTATION RESULT

TABLE RESULT

There were two sets of data that has been analyzed: data from time-based system and the

sensor-based system. These data obtained from the reports generated by Arena after the

entire simulation full. They were analyzed to see if the improvement in waiting time of

vehicle is succeeded or not. The data is compared by using the paired T -test, a way to

compare two sets of data to see if significant improvement has been made or not. The

paired T-test of the data acquired from the simulation is done in two tests: the paired T-test

of the data from the simulation in normal traffic condition and the paired T -test of the data

from the simulation of busy traffic condition. As the simulation generates vehicles in

random arrival time based on exponential distribution, average waiting time is different in

different simulation run.

The above Data show the simulation models for time based and sensor-based during run.

Simulation has been run for 200 seconds for 25 run for each .time-based and sensor-based

system in normal and busy condition.

50

Data from the reports generated in Arena is mean waiting compiled in Microsoft Excel

before the paired T –test is done using Microsoft Excel. Figure shows the time (in seconds)

of time-based system and sensor-based system in normal and busy condition.

All statistical data from simulation and paired T -test is compiled in Table . From here, t-

value is calculated at 10.087 for normal traffic condition and 4.5115 for busy traffic

condition. With t-value as calculated and degree of freedom is 24 (n-l), the p-value for

normal traffic condition is 4.l495TIO, whereas the p-value for busy traffic condition is

1.438y4. As both p-value is less than 0.05, it is safe to assume that there are different

values in both normal and busy condition, which suggests there are improvements if the

sensor is implemented in the system. Result of the study from simulation modelling of the

traffic light control system with time-based system and the sensor-based system showed

that there are a lot of improvements on waiting time of vehicles in the junctions if the

implementation of sensor is done to the traffic light\ system. Mean waiting time of time-

based traffic light system is around 20 seconds for both normal traffic condition and busy

traffic condition, while for sensor-based traffic light system, the mean waiting time for

vehicles in the junctions is about 7.5 seconds for normal traffic condition, and about 17

seconds for busy traffic conditions.

Within this study, the Arena simulation software, which is more appropriate for simulation

of manufacturing system, is used. While there are a lot of specific tools or simulation

software intended for traffic light studies available, the Arena software proves to be more

general purpose simulation software that can be used in simulation of the traffic light

control system. Therefore, in formulating optimal solutions for each of the traffic light in

the intersections, more appropriate tools can be used to study the traffic light system and to

improve the traffic condition at the intersection intended. However, some of the tools used

in studying the traffic light system are intended for specific purpose of the study or scarce

and hard to get. Hence a more general purpose tool such as Arena simulation software can

be configured in order to get the optimal solutions for the intended studies.

51

8 CONCLUSION

Traffic light control system involves a very complex study. Even implementing one traffic

light in a single junction involved a lot of studies to be done and there is no obvious

optimal solution. In the study there are four junctions of an intersection involved, therefore,

a more complex work needs to be done as the state of one light influences the traffic flow

and conditions of other junctions as well. While the work is to see if the implementation of

sensor in the traffic light control system can improve the waiting time of vehicles in the

junction of an intersection, it does not provide an optimal solution for the improvement of

the waiting time of vehicles in junctions as each parameter of the traffic light system such

as arrival rate of vehicles at the intersection, the average number of vehicles waiting in the

junction and optimal traffic light duration is different from one intersection to another.

These parameters need to be studied first to obtain the optimal solutions for the intended

traffic light system. However, the simulation done within the study provided general

solution for implementing sensors in the traffic light control system. Therefore, by

implementing sensor in traffic light system, the waiting time for vehicles in the junctions at

the intersection can be reduced significantly as has been proven by statistical method.

Further improvements can be made in the system by modifying the parameters in the

simulation suitable for intended studies.

52

9 FUTURE ENHANCEMENT

9.1 IMPLEMENTATION OF GSM

The system will inform the status of the patient to the hospital as the command

giving to the system in the ambulance. This section consists of temperature sensor

and a heart rate sensor which record the status of the patient. Whenever the driver

wants to sent the information about the status of the patient to the hospital, by

pressing the switch the system will send the information through SMS. In this way

the doctors were for the situation in the hospital.

53

Microcontroller

P89V51RD2

Temperature

sensorLM35Heart rate

sensor

ADC 0809

16x2 LCD Display

GSM modu

le

GSM Mobil

e

IR TX

2 Sets of IR RX for

road 1

9.1.1 GSM

GSM (Global System for Mobile Communications,

originally Groupe Spécial Mobile), is a standard set developed by

the European Telecommunications Standards Institute (ETSI) to describe

technologies for second generation (2G) digital cellular networks.

Developed as a replacement for first generation (1G) analog cellular

networks, the GSM standard originally described a digital, circuit switched

network optimized for full duplex voice telephony. The standard was

expanded over time to include first circuit switched data transport, then

packet data transport via GPRS (General Packet Radio Services). Packet

data transmission speeds were later increased via EDGE (Enhanced Data

rates for GSM Evolution) referred as EGPRS. The GSM standard is more

improved after the development of third generation (3G) UMTS standard

developed by the 3GPP. GSM networks will evolve further as they begin to

incorporate fourth generation (4G) LTE Advanced standards. "GSM" is

a trademark owned by the GSM Association.

9.1.2 HEART RATE SENSOR

Modern heart rate monitors usually comprise two elements: a chest

strap transmitter and a wrist receiver or mobile phone (which usually

doubles as a watch or phone). In early plastic straps water or liquid was

required to get good performance. Later units have used conductive smart

fabric with built-in microprocessors which analyse the EKG signal to

determine heart rate.

54

Strapless heart rate monitors now allow the user to just touch two

sensors on a wristwatch display for a few seconds to view their heart rate.

These are popular for their comfort and ease of use though they don't give

as much detail as monitors which use a chest strap.

More advanced models will offer measurements of heart rate

variability, activity, and breathing rate to assess parameters relating to a

subject's fitness. Sensor fusion algorithms allow these monitors to detect

core temperature and dehydration

Another style of heart rate monitor replaces the plastic around-the-

chest strap with fabric sensors - the most common of these is a sports bra

for women which includes sensors in the fabric.

In old versions, when a heart beat is detected a radio signal is

transmitted, which the receiver uses to determine the current heart rate. This

signal can be a simple radio pulse or a unique coded signal from the chest

strap (such as Bluetooth, ANT, or other low-power radio link); the latter

prevents one user's receiver from using signals from other nearby

transmitters (known as cross-talk interference).

In recent years smart phone applications have been developed that

measure the heart beat rate by tracking the acceleration at your chest (Sports

Heart Rate Monitor) or by tracking color changes in the light that passes

through your finger (Instant Heart Rate).

` Newer versions include a microprocessor which is continuously

monitoring the EKG and calculating the heart rate, and other parameters.

These may include accelerometers which can detect speed and distance

eliminating the need for foot worn devices.

There are a wide number of receiver designs, with various features.

These include average heart rate over exercise period, time in a specific

heart rate zone, calories burned, breathing rate, built-in speed and distance,

and detailed logging that can be downloaded to a computer.

55

9.1.3 TEMPERATURE SENSOR

The LM35 series are precision integrated-circuit temperature sensors,

whose output voltage is linearly proportional to the Celsius (Centigrade)

temperature. The LM35 thus has an advantage over linear temperature

sensors calibrated in ˚ Kelvin, as the user is not required to subtract a large

constant voltage from its output to obtain convenient Centigrade scaling.

The LM35 does not require any external calibration or trimming to provide

typical accuracies of ±1 ⁄4˚C at room temperature and ±3 ⁄4˚C over a full

−55 to +150˚C temperature range. Low cost is assured by trimming and

calibration at the wafer level.

The LM35’s low output impedance, linear output, and precise inherent

calibration make interfacing to readout or control circuitry especially easy.

It can be used with single power supplies, or with plus and minus supplies.

As it draws only 60 µA from its supply, it has very low self-heating, less

than 0.1˚C in still air. The LM35 is rated to operate over a −55˚ to +150˚C

temperature range, while the LM35C is rated for a −40˚ to +110˚C range

(−10˚ with improved accuracy). The LM35 series is available packaged in

hermetic TO-46 transistor packages, while the LM35C, LM35CA, and

LM35D are also available in the plastic TO-92 transistor package. The

LM35D is also available in an 8-lead surface mount small outline package

and a plastic TO-220 package.

9.1.3.1 FEATURE

Calibrated directly in ˚ Celsius (Centigrade)

Linear + 10.0 mV/˚C scale factor

0.5˚C accuracy guaranteable (at +25˚C)

Rated for full −55˚ to +150˚C range

56

Suitable for remote applications

Low cost due to wafer-level trimming

Operates from 4 to 30 volts

Less than 60 µA current drain

Low self-heating, 0.08˚C in still air

Nonlinearity only ±1⁄4˚C typical

Low impedance output, 0.1 Ω for 1 mA load

57

10 OUTPUT SCREEN SHOTS

10.1 TRAFFIC LIGHT CONTROL UNIT

Figure 10.1 Traffic Control Unit

58

10.2 AMBULANCE SECTION

Figure 10.2 Ambulance Section

59

12 REFRENCES

1. Albagul, A., Hrairi, M., Wabyudi, and Hidayatullah, M.F .. "Design

and Development of Sensor Based Traffic Light". Science

Publications 2006. American Journal of Applied Science, 3 (3), pp

1745-1749.

2. Altiok, T. and Melamed, B. "Simulation Modeling and Analysis

with Arena". Elsevier, UK. 2007.

3. Bham, G.H. and Benekohal, R.F. "A high fidelity traffic simulation

model bas sed on cellular automata and car-following concepts."

Transportation Research Part C, 1-32 Elsevier. 2004.

4. Caristi, J. 1988. "The Simulation Language SIMAN on

Microcomputer and Mainframe". Journal of Applied Mathematics

and Simulation Vol I Number 3 1988.

5. Coleri, S., Cheung, and S.Y., Varaiya, P. "Sensor Networks For

Monitoring Control". Department of Electrical Engineering and

Computer Science, University of California, Berkeley. 2004.

6. Furstenberg, K., Hipp, 1. and Liebram, A. 2003. "A Laser Scanner

For Detailed Traffic Data Collection and Data Control". 7th World

Congress on Intelligent Transport System

7. Gonzalez-Calleros, lM., Martinez-Carballido, l Muoz-

Arteaga, J. and Guerrero-Garcia, l, "An Iterative Method To Desigu

Traffic Flow Models". Digital Society. 2009

60

8. Kelton, W.D., Sadowski, R.P. and Sturrock, D.T. 2007. "Simulation

With Arena". McGraw Hill, New York. NY. 2004.

9. Koskinen, K., Setala, N. and Kosonen, 1. "Fuzzy Sigual Control -

FUSICO". Laboratory of Transportation Engineering, Helsinki

University of Technology. 2007.

10. Rakha, H. and Crowther, B "Comparison and calibration of

FRESIM and INTEGRATION steady-state- car-following

behavior". Transportation Research Part A 1-27 Elsevier Science

Ltd. 2003

11. Smaldone, T. ''Traffic Light Simulation: A Study Into How Long It

Takes Vehicles Stopped at Red Lights To Go and To Cross the Light

After It Turns Green". Modeling and Simulation Independent Study

Course, Rutgers University, Camden, N.J. 2001.

12 Tan, K.K., Khalid, M. and Yusof, R. "Intelligent Traffic Light

Control by Fuzzy Logic". Malaysian Journal of Computer Science,

Vol. 9 No. 2, December 1996, pp. 29-35

13. Wiering, M., Veenen lV., Vreeken l and Koopman, A. "Intelligent

Traffic Light Control". Intelligent System Group, Institute of

Information and Computer Science, Utrecht University, Utrecht, The

Netherlands. 2004.

14. Yang,C.L. and Wen, W. "Solving the Traffic Problem Using a

Simulation Model". International Conference on Information

Resource Proceedings (CONF-IRM 2008)

61