18-05-2012, 01:32 PM
DENSITY BASED TRAFFIC LIGHT CONTROL
37669227-Density-Based-Traffic-Light-Control-System.pptx (Size: 283.11 KB / Downloads: 49)
OPERATION
Also we have a junction where three lights (green, amber and red) are arranged on all four sides. We have three pairs of sensors across the roads marking as low, medium and high density zones respectively.
There will be a infrared transmitter and infrared receiver opposite to each other. We will place sensors at some distance apart from another pair .
When vehicles are filled and cross the first pair of sensors, then there will be an obstacle between transmitter and receiver and this leads to a digital signal (low or high) and the microcontroller assumes that there is low density traffic.
Description:
LEDs are semiconductor devices. Like transistors, and other diodes, LEDs are made out of silicon. What makes an LED give off light there are the small amounts of chemical impurities that are added to the silicon, such as gallium, arsenide, indium, and nitride.
When current passes through the LED, it emits photons as a byproduct. Normal light bulbs produce light by heating a metal filament until it's white hot. Because LEDs produce photons directly and not via heat, they are far more efficient than incandescent bulbs.
Regulator:
A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. we are using LM7805 regulator in this project .it may be used to regulate one or more AC or DC voltages .
Sensors:
In this we are using infrared sensors namely infrared transmitter and infrared receiver .the IR transmitter sends light ray to IR receivers. If there is any obstacles occurring between these two then the data signal is send to microprocessor and its act upon a signal.