4.1 Introduction

In this module, we will learn to make Light following robot.

Our basic requirement is to track the light and I have found LDR is the best solution for this. But we can’t connect the LDR resistor directly with the Arduino or the motor driver. We need to make a compatible circuit for that, and in this state, I have found my solution on LDR sensor Module which is very low in price and also very easy to connect with the Arduino board.

LDR is a Light dependent resistor, also known as photoresistor. This is the light sensitive device which is used to indicate the presence and absence of light or measure the intensity of light. LDR have a variable resistance that changes with the amount of light intensity fall on it. When the LDR is placed in dark means no light then the resistance will increase and when it is placed in light then the resistance will decrease.

So, in this project we will be using 3 LDR module for making the car move according to the light falling on the LDR module.When the light is falling in the middle LDR module then the car will move forward.Similarly for making the car move left or right we will use the rest of the 2 LDR module which is at the right and left side.