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'Smart' traffic lights

 
Traffic lights are important components of the road systems of a town or city. Their importance becomes obvious when they stop working. When this happens, the junction at which they operate is then reduced to chaos as drivers curse and swear to try to get across.

Despite their importance, some traffic lights, especially older ones, are not 'smart', meaning they turn n or off at fixed predetermined intervals regardless of whether it is midday or midnight. It is fine at midday when the roads are packed and waiting for one minute at a red light is normal. However waiting for one minute at a red light at midnight when here are no vehicles around seems like forever. One is tempted to beat the lights.

Fortunately in my town, the planners have installed 'smart' traffic lights that change their lights according to the absence or presence of cars near the junction. This works very well, especially in the night. One does not have to wait forever for the lights to change.

The 'smart' traffic lights have detectors buried just under the road just behind the line where vehicles stop at the lights. The detectors are hardly visible but if one is observant, one can see a rectangular box on the road about the same width and length of a car behind every line. Each detector can detect any vehicle that stops on top of or passes over it. When this happens, it indicates to the control box to change the lights to green as soon as possible. So the lights stay red or green according to the traffic volume registered by the detectors. It is pleasing to arrive at an empty junction to see the lights quickly change to green when one stops behind the line. One does not have to wait long.

The only setback to this system is that many drivers are not aware of the detectors. Some stop beyond the stop line or before it and wonder why the lights do not change to green for them. The detector did not register their presence so the lights do not change quickly.

I suppose 'smart' traffic lights require smart drivers as well. My parents know the drill well. So we never have problems at the 'smart' traffic lights.

     
setback   something that happens that delays or prevents a process from developing
     
drill   an activity that involves repeating the same thing several times
 
 
 

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