User Manual

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The TCRT5000 infrared photoelectric switch adopts a high transmit power infrared photodiode and
a highly sensitive phototransistor. It works by applying the principle of objects' reflecting IR light –
the light is emitted, then reflected, and sensed by the synchronous circuit. Then it determines
whether there exists an object or not by the light intensity. It can easily identify black and white
lines.
In other words, the different conduction levels of the phototransistor when it passes over black and
white lines can generate different output voltages. Therefore, all we need to do is to collect data
by the AD converter on the Atmega328 and then send the data to the master control board via
I2C communication.
This module is an infrared tracking sensor one that uses 5 TRT5000 sensors. The blue LED of TRT5000
is the emission tube and after electrified it emits infrared light invisible to human eye. The black
part of the sensor is for receiving; the resistance of the resistor inside changes with the infrared light
received.
Light Follower Module
Phototransistor, or photo triode, is a photoelectric conversion component that senses the light
intensity. The stronger light, the larger currents, and better conductivity of the triode.
Based on this principle, we use it for light following. It works by converting the conductivity to
voltage output, which means the stronger light shone on it, the smaller voltage output. Then