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ROBOTICS
LINE FOLLOWER
HARI KISHAN TANDEY – ES12B1008
DILIP KONDAPARTHI – ES12B1010
SAI KARTIK – CE12B1015
Indian Institute of Technology
Hyderabad
MODEL
ROBOT
 A robot is a mechanical or virtual artificial agent, usually an
electro-mechanical machine which performs a variety of
tasks that is guided by a computer program or electronic
circuitry.
 Types- Stationary robot, Mobile robot.
 Constitution of robot- locomotive system, power supply,
actuators, sensory devices for feedback, control system.

Applications- Manufacturing industry, medical science,
robots in space, national defense, transportation, agriculture
etc…
WHY ROBOTICS ?
 Robotics inspires to make connections across several
disciplines rather than learning topics in isolation as it
combines mechanical, electronic, electrical and programming
skills.




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It gives visual grasp of math and science
It builds logical thinking
It brings out innovation and creativity
It enhances problem solving skills.
As technology becomes increasingly important in today's
world, it is invaluable to not only learn how to use technology,
but also to understand how to create it.
ATMEGA8

It is a low power CMOS(Complementary Metal Oxide
Semiconductor) 8 bit microcontroller based on the AVR architecture.

Microcontroller consists of a Microprocessor which is interfaced to
RAM and Flash memory.

Features:
It has
8 KB of flash memory
512 bytes of EEPROM
1 KB of SRAM
23 general purpose I/O lines
32 general purpose working registers
PROGRAMMING
 Program is written in C language.
 Code is written to give instructions to computer to
perform a particular task in a particular condition.
 Code is compiled to generate machine file.
 Computer only understand this machine file which is in
the language of 0 & 1.
 Now this file is been feed in the memory of the
microcontroller.
PORT
 PORT is usually a collection of 8 pins.
 Input Output functions are set by Three Registers for each
PORT.
 DDRX ----> Sets whether a pin is Input or Output of PORTX.
 PORTX ---> Sets the Output Value of PORTX.
 PINX -----> Reads the Value of PORTX.
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PORTB
PORTC
PORTD
Digital
- Analog + Digital Digital
-
Output
Input
Output
MOTOR
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Two motors have been used to rotate the two wheels
clockwise or anticlockwise. This provides motion to the robot.
Motors are arranged in a fashion called H-Bridge.

H-Bridge-It is an electronic circuit which enables a voltage
to be applied across a load in either direction.

It allows a circuit full control over a standard electric DC
motor. That is, with an H-bridge, a microcontroller, logic chip,
or remote control can electronically command the motor to go
forward, reverse, brake, and coast.
MOTOR

To power the motor, two switches are turned on that are
diagonally opposed in the H-Bridge.

The combination of switches that are on, decide the motion
of robot whether it will go forward, backward or take turn.

IR Analog Sensor:Transmitter- An infrared emitting diode.
Receiver- A phototransistor.
WORKING MODEL

The working model of a line follower consists of two motors,
one ATmega8 circuit board, two wheels, two IR sensors, LEDs,
wires and power supply.

The IR sensors get the input and according to the program the
LEDs glow depending on the input. The two motors rotate
together in one direction to go forward or backward. For taking a
right turn, the motor at right side stops and left side one
continues to rotate. This rotation depends on the program which
gives instructions to the motor depending on the input that
sensor gives.

IR sensors provide the input, motors give the output and the
wheels make the robot to follow a line.
WORKING MODEL

Follower robot is a mobile machine that can follow a path.
The path can be a visible black line on a white surface.

The IR sensors receive an analog signal that depends on
the intensity of light reflected by the black line of emitted
beam by the LEDs.

These signals are sent to the ADC comparator which
creates digital signals that are sent to Microcontroller.
 The microcontroller gives instructions to motor to perform
work.
.
REFERENCES
 www.wikipedia.org
 www.i3indya.com