The document describes the design of a line follower robot using an Arduino kit. The robot uses IR sensors mounted on the front left and right to detect a black line on a light surface. When both sensors detect white, the robot moves forward. When one sensor detects black, the microcontroller stops the associated motor, causing the robot to turn in the direction of the line. Potential applications include use in industrial equipment transport, as automated vehicles, for domestic tasks like cleaning, and for guidance in public spaces.

1. CENTER FOR CONVERGING TECHNOLOGIES
University of Rajasthan
Line Follower
Robot
Submitted by-
Tushar Attar ,Saurabh Sahoo, Sanket Sachdeva, Vishal Joshi
Trilok Keswani, Roshan Sharma, Vinod Sharma, Shubham Shroti

2. 1
OBJECTIVE
To design a line follower using Arduino kit..
MATERIALS REQUIRED
Arduino kit, 9V batteries, black tape, USB wire, chassis,
connecting wires.
PRINCIPLE
What is Arduino?
Arduino is a tool for making computers that can sense and control
more of the physical world than a desktop computer. It's an open-
source physical computing platform based on a simple
microcontroller board, and a development environment for
writing software for the board.
This robot is designed to continuously follow a black line painted
on a bright surface or a white line on a dark surface and take the
turns along with the line automatically. For situations such as
cross over where the robot can have more than one path that can
be followed, predefined path must be followed by the robot.
.

3. 2
To make the robot follow the black line, IR sensors are employed
with the fact that black surface absorbs light and white surface
reflects light.
The sensors are mounted on left front end and right front end of
the robot keeping the black line lies in between them. Until
sensors are getting the reflected light, the comparator sends logic
1 to the microcontroller and the microcontroller in turn switches
ON the motor associated with the sensor and when any of the
sensors comes up on the black line the microcontroller stops the
motor associated with that sensors and make the robot to turn in
the direction of the black line.

4. 3
Fig. Working of IR Sensors
Fig. IR Sensors
A passive infrared sensor (PIR sensor) is an electronic sensor that
measures infrared (IR) light radiating from objects in its field of view.
They are most often used in PIR-based motion detectors.

5. 4
Connections:-
Truth table:-

6. 5
Line-Follower Concept
 When both left and right sensor are sensing white, means
black line is in between and bot goes forward.
 When Right sensor senses black means a Right Turn. Turn off
the Right Motor so that it turns Right until Right Sensor senses
white again.
 Similarly for Left turn.
 Line-Follower Robot.

7. 6
Program to run motor
int switchpin = 9; // switch input
int motor1pin1 = 3; // pin 2 on L293D
int motor1pin2 = 4; // pin 7 on L293D
void setup()
{
// set the switch as an input:
pinMode(switchpin, INPUT);
// set all the other pins you're using as outputs:
pinMode(motor1pin1, OUTPUT);
pinMode(motor1pin2, OUTPUT); }
void loop()
{
// if the switch is high, motor will turn on one direction:
if (digitalRead(switchpin) == HIGH)
{
digitalWrite(motor1pin1, HIGH); // set pin 2 on L293D high
digitalWrite(motor1pin2, LOW); // set pin 7 on L293D low
}
// if the switch is low, motor will turn in the opposite direction:
else
{
digitalWrite(motor1pin1, LOW); // set pin 2 on L293D low
digitalWrite(motor1pin2, HIGH); // set pin 7 on L293D high
}
}

8. 7
APPLICATIONS OF LINE FOLLOWER-:
o Industrial Applications: These robots can be used as automated
equipment carriers in industries replacing traditional conveyer
belts.
o Automobile applications: These robots can also be used as
automatic cars running on roads with embedded magnets.
o Domestic applications: These can also be used at homes for
domestic purposes like floor cleaning etc.
o Guidance applications: These can be used in public places like
shopping malls, museums etc to provide path guidance.