Design And Construction Of A Solar Powered Intelligent Vehicular Four-Way Traffic Light Controller

ABSTRACT

The steady supply of public power has always been a challenge in third world countries. The proposed solar based smart four-way junction traffic light is to work independent of public power supply using abundant renewable energy (solar). The solar traffic light is powered by battery which is charged during the day with solar PV and the battery continues working during the night. Managing traffic at a four way junction by humans can be a very complex and daunting job. A Four-way traffic light can be used to solve this problem. The traffic lights on each lane controlled by a micro controller and the four micro controllers are interconnected. The system displays the time allowed for passing and for waiting for each of the four lanes using a seven segment display. Ambulances are given special preferences and therefore have a Radio Frequency Transmitter; their corresponding radio frequency Receiver is connected to one of the micro controllers. This enables the system to activate the red LED on all lanes to enable the ambulance to have the right of way. The system was designed and simulated using Proteus, and then the hardware was implemented. The Circuit can be used to control traffic at four way junctions.

CHAPTER ONE

   1.1                                                   INTRODUCTION

Solar energy can be used to generate power in two-ways; solar thermal conversion and solar electric (photovoltaic) conversion. Solar thermal is employed in heating of fluids to produce steam to drive turbines for large scale centralized generation while solar electric (photovoltaic) which is considered in this paper, is the direct conversion of sunlight into electricity through photocells. A charge controller is an essential part of nearly all power systems that charge batteries, whether the power source is PV, wind, hydro e.tc [1]. A PV system consists of a PV array which converts sunlight to direct – current electricity, a control system which regulates the battery charging and operation of the load, energy storage in the form of secondary batteries and loads. The main function of a charge controller in a PV system is to keep batteries properly charged and safe for the long term, and to protect it from deep discharging [1], without a charge controller, the battery will overcharge. Absence of charge controller in PV system results in high maintenance cost including frequent battery replacement. Hence, a charge controller is important to prevent battery overcharging excessively, over discharging, reverse current flow at night and to prolong the life of the batteries in a PV system [1].

Traffic monitoring and controlling is a difficult task. The flow of the traffic constantly changes depending on the time of the day, day of the week and time of the year. At times, road construction and accidents further influence the complexity. Even for single junctions there might be no obvious solution and the problem becomes even more complex for the multiple junctions, as the state of one light in one junction directly influences the flow of traffic towards many other lights. With the ever increasing vehicles on the road and the number of road users, the limited resources provided by current infrastructure leads to ever increasing travelling times. Hence, intelligent control of traffic is an important issue to be considered. The services of our traffic wardens as well as that of the policemen can no longer adequately contain the situation; they cannot carry out a twenty-four hour duty. One way to improve the traffic flow and safety of the current transportation system is to apply automation and intelligent control methods to roadside infrastructure and vehicles. There are several models for traffic simulation. In our research, we intend to develop a cost effective system using Radio frequency (RF) technology, switches and latest high speed microcontroller [2] to achieve the desired results. The primary objective of this project is to identify the road emergency vehicle such as ambulances and police cars and give them the right of way. Traffic jams may arise due to large red light delays which are hard coded and is independent of traffic [3]; in order to solve this problem an attempt will be made to design, and construct a four- way traffic light control system. Traffic lights alternate the right of way accorded to road users by displaying lights of a standard colour (red, amber, and green) following a universal colour-code and the whole system being powered by solar/battery. In the typical sequence of colour phases:

• The green light allows traffic to proceed in the direction denoted, if it is safe to do so
• The yellow/amber light denotes prepare to stop short of the intersection, if it is safe to do so
• The red signal prohibits any traffic from proceeding

 1.1                                                                                                 OBJECTIVE OF THE PROJECT

The main objective of this work is to control an intelligent signaling devices powered by solar panels Positioned at road intersections to control the flows of traffic.

    1.2                                                     PURPOSE OF THE PROJECT

The purpose of this work is to control the flows of traffic using solar energy and intelligent signaling device.

    1.3                                                                                      SIGNIFICANCE OF THE PROJECT

Timed Colored Petri Net (TCPN) formalism [4] was used to design and simulate a model for a multi-phase traffic light controlled intersection with an associated fixed signal timing plan using +-type junction, while [5] proposed a system which can 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.

1.4                                              SCOPE OF THE PROJECT

The system is based on a micro controller, IR (infrared) sensors and Radio Frequency Identification (RFID) technology. In [6] the proposal was a multiple traffic light control and monitoring system using micro-controller 89V51RD2 (MCS-51 family based) with IR transmitter and IR receiver which are mounted on the either sides of roads respectively to count vehicle and the count is recorded. This data is then sent to a central control room where an administrator can make decisions to reduce traffic congestion. The  major disadvantage of this system is that it requires major human input and this defeats the use of automation. The system designed in [7] focused on emergency vehicles, once a signal is received from an emergency vehicle, the sequence of right of road use is changed and once the vehicle passes the junction, the normal sequence is restored. It makes use of Radio frequency and PIC16F877A. Transmission through RF is better than IR due to the following reasons. First, signals through RF can travel through larger distances making it suitable for long range applications. Also, while IR mostly operates in line-of-sight mode, RF signals can travel even when there is an obstruction between transmitter and receiver. RF transmission is stronger and more reliable than IR transmission. RF communication uses a specific frequency unlike IR signals which are affected by other IR emitting sources. Conventional technologies for identifying the emergency vehicle use some image processing systems. But these image processing systems are affected by the bad weather conditions like wind, rain, fog, etc., during the bad weather conditions, the image received by the camera is distorted by noise and it is not clear for the system to identify the vehicle. Thus, we propose a system using RF transmitter and receiver. The advantage of RF is that it is a cost effective system and it provides uninterrupted communication even in bad weather conditions.

1.5                                              ADVANTAGES OF THE PROJECT

1. Solar traffic lights are self-sufficient as they do not require external power sources.

1. They are easy to set up and operate.
2. They require very little to no maintenance as they have no moving parts.

1.6                                                   PROBLEM OF THE PROJECT

1. Risk of theft is higher as equipment costs are comparatively higher.
2. Snow or dust, combined with moisture can accumulate on horizontal P-panels and reduce or even stop energy production.

• Rechargeable batteries will need to be replaced several times over the lifetime of the fixtures adding to the total lifetime cost of the light. The charge and discharge cycles of the battery are important considering the overall cost of the project.

    1.7                                      APPLICATION OF THE PROJECT

1. This device is used in a + – junction to control vehicular traffic.
2. Solar traffic lights can also be used during periods following natural disasters, when the existing street lights may not function due to power outages and the traffic is uncontrollable. Street lights used in such scenarios are designed to be portable enough to be carried and operated by police and relief workers wherever traffic needs to be regulated

1.8                                        PROJECT WORK ORGANIZATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to this study. In this chapter, the background, significance, objective, purpose, limitation and problem of this work was discussed.

Chapter two is on literature review of a variable dc motor drive. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.