“A photoresistor is a light-controlled variable resistor.The resistance of a photoresistor decreases with increasing incident light intensity; in other words, it exhibits photoconductivity. A photoresistor can be applied in light-sensitive detector circuits, and light- and dark-activated switching circuits.This tutorial will use four photoresistors (light dependent resistors) and Evive to control the motion of a robot. Any common robot chassis can be used for the robot. The light sensors will be mounted on the left side, right side , front and back of the robot. When light of sufficient intensity falls on a sensor, the robot will respond with a left turn, right turn, forward or about turn (i.e. 180°) movement, corresponding to the location of the sensor that is activated.”
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