Abstract
A microcontroller-based Versatile Traffic Light Control System/Trainer
has been designed and implemented in the course of this project. The
system can control traffic lights in all types of y- and cross-junctions.
Two major aspects of the system are the hardware subsystem and the
software subsystem. Each subsystem was first broken down into simpler
parts or modules and each module was designed from first principles to
get the required functional behavior. The entire system was then
integrated into one functional unit and tested using a carefully laiddown test plan. The versatility of the system was made possible by the
use of a microcontroller which enabled the researcher to use software to
achieve a versatile, flexible and cost-effective solution. The system can
double up as a training kit for undergraduates that are interested in
learning traffic light control system design and operation.
1.1 Background
Most roads in Nigeria urban areas are usually congested, some all-day,
others during rush hours. It was found that larger part of this problem is
that due to congestion at road intersections. However, traffic light systems
have long been invented to control this problem. Most of these traffic
light control systems are imported thereby making them expensive.
Traditional traffic light control systems are designed to function at only a
particular type of traffic intersection. For example, a control system that
was designed for a cross-junction may not serve at T-junction.
This project work deals with a microcontroller-based traffic light
control system that has the ability to control any type of y- and crosstraffic intersections. It is indigenous as well as versatile in its control
functions as regards y- and cross-junctions. This has the effect of
drastically reducing the design cost.
1.2 Aim and Objectives
This project aims at developing an 8051 microcontroller-based versatile
y- and cross- traffic light control system which can be deployed at road
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intersections for traffic control. It can be used as a teaching aid in schools
for various road users. The purpose of this project work is to develop a
versatile system that can control any type of cross- and y-traffic junctions
to assist and to educate the general public on automobile-automobile and
automobile-pedestal interactions at road intersections.
1.3 Justification
Since this work is indigenous, it can serve to replace the imported ones. It
can also reduce the cost of design and implementation since addition of
few instruction lines to the control program will make the control system
function at any type of road intersection. The software program for this
system can be modified to incorporate more functionality. This
system/trainer also serves as a learning aid.
1.4 Scope of the Work
This versatile traffic light control system is intended to control a wide
range of y- and cross- road intersections. In this work, we limit ourselves
to the control of the following types of traffic junctions:
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? Automobile-automobile cross-junction
? Automobile pedestrian cross-junction
? Automobile-automobile Y-junction using LEDs
? Automobile-automobile Y-junction using lamps via dc relays
This project work is flexible in that the control program can be modified
to incorporate other types of traffic junction control.
1.5 Block Diagram OverviewFig. 1: Block Diagram Overview
As indicated in Fig. 1 above, the input subsystem comprises a switch
panel that passes input signals to the control system which in turn invokes
control algorithm from the system’s memory for its control operations.
The input signal is used to configure the system to behave as a particular
type of traffic junction controller. The user can select one out of
INPUT
SUBSYSTEM
CONTROL
SUBSYSTEM
OUTPUT
SUBSYSTEM
CONTROL
ALGORITHM
(IN MEMORY)
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the four types of junction controls at the time of configuration prior to
installation of the panel. When used as a trainer, selection is also made in
a similar manner.
The timing signals are used to control the sequencing of light. The light
change cycles through GREEN, AMBER and RED in response to the
timing requirements of the system.
1.6 Project Outline
This project work is organized as follows: chapter one is on introduction
while chapter two deals with a review of some related literature.
Methodology and systems analysis is the subject of chapter three while
chapter four covers hardware and software design details. Chapter five is
concerned with system implementation and testing while summary and
conclusion is the subject of chapter six.