Program for the control of a traffic light system at a street junction with pedestrian crossing.
Figure :Traffic light at junction diagram
The requirements for the timing cycles for the traffic lights are the following:
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Initially the main road vehicles will have a green light.
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Pedestrians can request a green light by pressing either pushbutton. The pedestrian green light should blink before going to red. Pedestrians should get a green light only if all road traffic lights are red. A POT is used to determine the time the pedestrian traffic light should stay green (for simulation purposes, a full scale POT value, 1024, should correspond to a time of 10 seconds).
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The coils buried in the side road next to the traffic light can detect whether one or more than one car is waiting in front of the traffic light. Note, a second POT is used in this traffic light model to emulate the function of the coils. A value of 512 simulates that a car is waiting. When cars coming out of the side road get a green light, main road light should be red.
The progrem is simulated using Tinkercad shown in the video below.
