Adaptive Traffic Light - Capacity Planning

CHAPTER 1: INTRODUCTION

 In this project we show the concept of adaptive logic traffic light. We have used the concept of adaptive logic on two sides with the help of infra red sensor. Adaptive logic is active in the green light. If no traffic is on road while green light is active then the timing of green light is reduced .When traffic is normal then counter shows a normal light timing. When traffic is dense then counter shows a double timing. For this purpose we use two counters.

In our country, India and most parts of the world traffic lights change after a period of fixed and predetermined time. This system does not take into account the vehicle density of the road. This is a major drawback of this system as this often leads to traffic jams and congestion.

The Project is aimed at developing Adaptive Traffic Light signal using Microcontroller. Nowadays congestion in traffic is a serious issue. The traffic congestion can also be caused by large Red light delays, etc. The delay of respective light is hard coded in the traffic light and it is not dependent on traffic. Therefore for simulating and optimizing traffic control to better accommodate this increasing demand arises. The system proposed changes the traffic  signal light based on the density of the traffic in the road. The proposed system will certainly help in reducing traffic by managing traffic better than the current system.

CHAPTER 2: MODE OF PROJECT

• To measure the traffic intensity: in this mode we use the IR sensor pair for checking the intensity of traffic light.

            There are three levels of traffic:

1. Normal level:  In this level system automatically increase the counter value or timing of green light according to requirement.
2. Middle level: In this level system automatically increase the counter value or timing of green light according to requirement.
3. High density level: In this level system automatically increase the counter value or timing of green light according to requirement.

For indication in control room: With the help of led indication we demonstrate the level of traffic light. When there is no vehicle between both the sensors, it will be low level mode and green light timing will be low. When there are vehicles between one of the two sensors then it will be medium level mode and green light timing increases. If both the sensors detect vehicle then it is High mode and green light timing is maximum.
If both the roads show high vehicle density then the green light is given for maximum time at the both the traffic light signals.

Chapter 2.1: Various System Diagrams

[pic 1]

220V AC

.

[pic 2]

Fig 1: Block Diagram

[pic 3]

FIG.2 Overview of the System

Circuit diagram

[pic 4]

FIG.3 Circuit Diagram

Chapter 2.2: POWER SUPPLY

In this project firstly we use one step down transformer. Step down transformer steps down the voltage from 220 volt Ac to 12 volt Ac. This Ac voltage is further converted into DC with the help of rectifier circuit. In rectifier circuit we use two diodes. All the diodes are arranged as a bridge rectifier circuit. Output of this rectifier is pulsating Dc. To convert this pulsating DC into smooth dc we use one capacitor as a filter component. Capacitor converts the pulsating Dc into smooth DC with the help of its charging and discharging effect.

Output of the rectifier is now regulated with the help of IC regulator circuit. In this project we use positive voltage regulator circuit. Here we use three pin regulator. Output of this regulator is regulated voltage. If we use 7805 regulator then its means it is 5 volt regulator and if we use 7808 regulator then its means that it is 8 volt regulator circuit. In this project we use 5 volt dc regulated power supply for the complete circuit. Separate 9 volt dc power supply is used for the relay coil.

[pic 5]

Fig 4 Power Supply Circuit

Chapter 3: Hardware

List of Components Used:

1. Step Down Transformer
   
2. Diode (IN4007)
   
3. Voltage Regulator (7805)
   
4. LED
   
5. Resistors
   
6. Capacitors ( Electrolytic & Ceramic)
   
7. Crystal Oscillator( 11.0592 Mhz)
   
8. Resistor Array
   
9. LM-339 (Comparator)
   
10. Seven Segment Display

Chapter 3.1: Step Down Transformer

It is designed to reduce the voltage from the primary winding to the secondary winding. This kind of transformer “steps down” the voltage applied to it.

As a step-down unit, the transformer converts high-voltage, low-current power into low-voltage, high-current power. The larger-gauge wire used in the secondary winding is necessary due to the increase in current. The primary winding, which doesn’t have to conduct as much current, may be made of smaller-gauge wire.

[pic 6]

Fig 5 Step down transformer

The step down transformer used in this system is the 12-0-12 transformer or 500A.This means that it will convert the input 220 V to 12 V, that is it performs to step down action. The 12 V wires are connected to the full wave rectifier diodes and the ground wire is connected to the common ground of the PCB

Chapter 3.2: Diode (IN4007)

A diode is an electrical device allowing current to move through it in one direction with far greater ease than in the other. The most common kind of diode in modern circuit design is the semiconductor diode.