1.1 Introduction
Traffic lights, also known as traffic lamps, traffic signals, stoplight, stop-and-go lights semaphore or robots, are signaling devices positioned at pedestrian crossings, road intersections, and other locations to control competing flows of traffic. Traffic lights have installed in most cities around the world to control the flow of traffic. It assign the right of way to road users by the use of lights in standard colors (Red - Yellow - Green), using a universal color code (and a precise sequence, for color blind). Traffic lights are used at busy intersections to more evenly apportion delay to the various users. The increasing amount of traffic in the cities has a large impact on the congestion and the time it takes to reach a certain destination. The traffic light system is made up of all the components and circuits used to realize to lighting effect at the Output.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In the ever fast-growing world of business and technology today, there has become an increasing column of vehicles on every road in different place of the world. Traffic control light has become a very effective tool for sequential control of the teaming number of vehicles on the road to avert what would have been a recurrent saga of ghastly accidents at the junctions. There have been many ways of achieving this, uppermost among these being the employment of electronic monitoring circuits that which is controlled by presto clock.
In developed countries, the employment of traffic personnel who would be jumped up and down at the centres of the junction just for the motorists to acknowledge their rigorous signs has long come of age. In developing countries where 24 hours traffic flow is involved, many societies are adopting the usage of the traffic light control. The advantage offered by this method of traffic control cannot be over emphasized. For one, it offers a more advanced technology that is less prone to miscalculation and its regrettable occurrence. They stand out better at night, then offer illumination to the immediate surroundings which become important for security purpose and in general add to their entire aesthetic beauty of night life.
The technology behind the design may vary from place to place, but the fact remains that in all cases an electronic (logic) circuit is made to control a power circuit. The electronic logic circuit is normally composed of the basic digital components of electronic design which includes oscillators, timers, counters, decoders, microprocessors, etcetera, while the power circuit includes the lamps and the drivers circuits. The digital circuit is designed to give an output commensurate to the design choice. The power supply unit is designed to generate a steady supply voltage which is used to power the logic circuit.
Traffic lights are signaling devices that are positioned at road intersections, pedestrian crossings or two or more roadways to control the competing flows of vehicle and human traffic in an orderly manner without which the busy roads would be chaotic. This is achieved by providing a visual indication to drivers when to proceed, when to slow down, when to stop and at times when to take a turn. Traffic lights are installed in almost all the cities in the world to control the flow of traffic. They are used to assign the right of way to road users by the use of lights in standard colours (Red Amber Green). They are very useful at busy intersections which are used to evenly apportion delay to the various users on different lanes. These signals may be operated manually or by a simple timer which allows traffic to flow on one roadway for a fixed period of time, and then on the other road-way for another fixed period of time before repeating the cycle.
The output consists of a series of lamps which are expected to light in a particular sequence depending on the design. By the logic circuit design, the lamps are made to come up in a particular sequence depending on the design with each colour meaning different motional status of the vehicles in that column.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to Design and Construct a Four Way Traffic Light Control Circuit.
1.3 Statement of Problems
Investigation revealed that the need for traffic control started even before the invention of automobiles. Then the traffic consisted of wagons, horse carts, bicycles and pedestrians only, but this on its own caused problems at busy road intersections. To control the traffic, police officers were assigned at the intersections to control the flow of traffic.
1.4 Aim and Objectives of Study
The aim of the study is to Design and Construct a Four Way Traffic Light Control Circuit. In achieving this aim, the following specific objectives were laid out as follows:
- To construct a Four Way Traffic Light Control Circuit that will efficiently and effectively control the traffic light for twenty-four hours.
- To build a prototype four-way traffic light control circuitry.
- To design a system that will direct vehicles in order to illuminating the environment in the night
Going by the rapid advancement in technology all over the world, the need for better ways of solving a problem keep coming up every day. Necessity is the mother of invention. It has become imperative for societies, companies, industries, business ventures, clubs etc to offer 24 hour service, hence thereby has to be a way of controlling the teaming column of vehicles which convey both individuals and goods to different destinations of that type.
The most elegant way of directing the motorists is by the use of traffic light control. This type of control serves a dual purpose. In the day type it directs the vehicles, whereas it turns out to additionally illuminating the environment in the night, so that at very far distance, its effect is noticeably felt, conveying its message to an oncoming vehicle very far from the point.
1.5 Significance of Study
This study will be of immense benefit to Road Safety Officers, Engineering student and other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.6 Scope of Study
The scope of the research is focused on Design and Construction of Four Way Traffic Light Control Circuit.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection.
1.8 Methodology
Priority was given to the nature of the junction and how far away they are at different seasons of the year. A lot of design research was carried out on digital logic design and choice of digital families. Data books were consulted to make the most suitable choice of components at the most reasonable cost.
After the design, a market survey was conducted and some components used in the design were not obtainable in the market. Hence, alternative components had to be used and the circuit redesigned. The subsequent stage involves physically realizing the design work, constructing and packaging the entire circuitry on the frame. Finally, he work was given a fine finish and tested.
