TRAFFIC SIGNAL
KRUTHIKA R N
U11GT21C0387
I Year B.Com, Second Semester
Government First Grade College, Tumkur -572104
kruthikarn231@gmail.com Ph.no: 6361495806
Traffic lights, traffic signals, or stoplights – known also as robots in South Africa are signalling devices positioned at road intersections, pedestrian crossings, and other locations in order to control flows of traffic.
Traffic lights consist normally of three signals, transmitting meaningful information to drivers and riders through colours and symbols including arrows and bicycles. The regular traffic light colours are red, yellow, and green arranged vertically or horizontally in that order. Although this is internationally standardised, variations exist on national and local scales as to traffic light sequences and laws.
The method was first introduced in December 1868 on Parliament Square in London to reduce the need for police officers to control traffic. Since then, electricity and computerised control has advanced traffic light technology and increased intersection capacity. The system is also used for other purposes, for example, to control pedestrian movements, variable lane control (such as tidal flow systems or smart motorways), and railway level crossings.
HISTORY
The first system of traffic signals was installed as a way to replace police officer control of vehicular traffic outside the Houses of Parliament in London on 9 December 1868. In the first two decades of the 20th century, semaphore traffic signals like the one in London were in use all over the United States with each state having its own design of the device. In many cases, it was controlled by a traffic officer who would blow a whistle before changing the commands on this signal to help alert travellers of the change.
In 1912, the first electric traffic light was developed by Lester Wire, a policeman in Salt Lake City, Utah. It was installed by the American Traffic Signal Company on the corner of East 105th Street and Euclid Avenue in Cleveland, Ohio. The first four-way, three-colour traffic light was created by police officer William Potts in Detroit, Michigan in 1920. He was concerned about how police officers at four different light signals could not change their lights all at the same time. The answer was a third light that was coloured yellow, which was the same colour used on the railroad. In 1922 traffic towers were beginning to be controlled by automatic timers. The main advantage of the use of the timer was that it saved cities money by replacing traffic officers. The city of New York was able to reassign all but 500 of its 6,000 officers working on the traffic squad; this saved the city $12,500,000.
The control of traffic lights made a big turn with the rise of computers in America in the 1950s. One of the best historical examples of computerized control of lights was in Denver in 1952. In 1967, the city of Toronto was the first to use more advanced computers that were better at vehicle detection. The computers maintained control over 159 signals in the cities through telephone lines.
TRAFFIC SIGNAL CYCLES
Generally, at least one direction of traffic at an intersection has a green light (green aspect) at any moment in the cycle. In some jurisdictions, for a brief time, all signals at an intersection show red at the same time, to clear any traffic in the intersection. The delay can depend on traffic, road conditions, the physical layout of the intersection, and legal requirements. Thus modern signals are built to allow the "all red" in an intersection, even if the feature is not used.
Some signals have no "all red" phase: the light turns green for cross traffic the instant the other light turns red.
Another variant in some locations is the pedestrian scramble, where all the traffic lights for vehicles become red, and pedestrians are allowed to walk freely, even diagonally, across the intersection. Use of the Pedestrian signals (see below) will alter the traffic signal cycle. Variations
A traffic signal in Halifax, Nova Scotia, with specially shaped lights to assist people with colour blindness
In the Canadian province of Quebec and the Maritime provinces, lights are often arranged horizontally, but each aspect is a different shape: red is a square (larger than the normal circle) and usually in pairs at either end of the fixture, yellow is a diamond, and green is a circle. In many southern and southwestern U.S. states, most traffic signals are similarly horizontal in order to ease wind resistance during storms and hurricanes.
Japanese traffic signals mostly follow the same rule except that the "go" signals are referred to as 青 (blue), which they historically were in fact, but this caused complications with the international "green for go" rule, so in 1973 a decree was issued that the "go" light should be changed to the bluest possible hue of green, thus making it factually greener without having to change the name from blue to green.
Red – Stop, do not proceed
Red and Yellow - Get ready to proceed, but do not proceed yet
Green – Proceed if the intersection or crossing is clear, vehicles are not allowed to block the intersection or crossing
Yellow - Stop, unless it is unsafe to do so.
A speed sign is a special traffic light, variable traffic sign, or variable-message sign giving drivers a recommended speed to approach the next traffic light in its green phase and avoid a stop due to reaching the intersection when lights are red.
A traffic signal is used as an instructing device that indicates the road user to act according to the displayed sign. Following the traffic signal ensures road safety and to make things simple to understand, these signals have been using a universal colour code.
The road rules make certain the saving of lives through desirable modes of behavior on the road. The prime rules are as follows:
SIGNIFICANCE OF TRAFFIC RULES
Traffic rules are not made by the government for earning money out of them. It is for the protection of the drivers. Driving tests are also conducted to fulfill the same purpose. Knowledge of the traffic signs (the sign of speed limit, no entry, and stop signs) is necessary.
These help in maintaining a moderate speed, not entering the prohibited places and stopping by lowering the speed of the vehicle respectively. Following the rules of the road provide our experience. Thus, it assists in avoiding accidents.
Another important cause to follow traffic rules is that we can protect several other lives too by our responsible driving. The number of cattle dying because of road accidents can be decreased. Also, we will inculcate healthy habits in ourselves. Giving up drinking of alcohol also adds to the measure for safe driving.
CONCLUSION
We observe a number of accidents taking place each day because of irresponsible driving. Just for saving a little amount of time we don’t even care for our valuable lives. Also, we are prepared to place the life of others in danger too!! Such irresponsible behavior needs to be changed. Traffic Rules teach us to become good and accountable citizens of the motherland.
There is a popular saying” Slow and steady wins the race.” Thus, drive cautiously and reach your destination safely. Only when you will reach safe, you can win time for your family and for the service of the nation at large!!