OBSTACLE AVOIDACE ROBOT USING ARDUINO UNO AND ULTRASONIC SENSOR

NAL REPORT
1)Jeevan Prakash H A
–20BRS1259 (Leader)
Ashvant N.-20BEC1292
HE HAS LEFT THE COLLEGE.ALL ARE DONE BY MYSELF

ECE 1006
NANOSCIENCE AND
NANOTECHNOLOGY

NANOSCIENCE AND NANOTECHNOLOGY
A project report submitted to
Dr. ARIVARASI A
SCHOOL OF ELECTRONICS ENGINEERING
in partial fulfilment of the requirements for the course of
ECE 1006 NANOSCIENCE AND NANOTECHNOLOGY
In
B. Tech School of Computer Science and Engineering
Kelambakkam - Vandalur Rd, Rajan Nagar,
Chennai, Tamil Nadu 600127

TITLE OF THE PROJECT
OBSTACLE-AVOIDING ROBOT
BY
JEEVAN PRAKASH HA-20BRS1259

BONAFIDE CERTIFICATE
Certified that this project report entitled “OBSTACLE-AVOIDING ROBOT ” has
Bonafede worker JEEVAN PRAKASH HA 20BRS1259 who carried out the
Project work for ECE 1006 NANOSCIENCE AND NANOTECHNOLOGY
.
Dr. ARIVARASI
Associate Professor
School of Electronics
Engineering,
VIT University, Chennai
Chennai –600 127.

ACKNOWLEDGEMENT
We wish to express our sincere thanks and deep sense of gratitude to our project guide, Dr. ARIVARASI A,
Associate Professor, School of Electronics Engineering, for her consistent encouragement and valuable
guidance offered to us in a pleasant manner throughout the course of the project work.
We are extremely grateful to Dr. JAGADEESH KANNAN R, Dean of School of Computer Science and
Engineering, VIT Chennai, for extending the facilities of the School towards our project and for his unstinting
support.
We express our thanks to our Head of the Department Dr. REKHA D for his support throughout the course
of this project.
We also take this opportunity to thank all the faculty of the School for their support and their wisdom
imparted to us throughout the course.
We thank our parents, family, and friends for bearing with us throughout the course of our project and for the
opportunity they provided us in undergoing this course in such a prestigious institution.
NAME WITH SIGNATURE NAME WITH SIGNATURE

CONTENTS
1. INTRODUCTION
2. ARDUINO
3. INFRARED SENSORS
4. MICROCONTROLLER
5. L298D Motor Driver Shield
6. SG-90 Servo Motor
7. DC Motor – Overview
8. CODING
9. APPLICATION OF OBSTACE AVOIDANCE ROBOT
10.SIMULATION
11.CONCLUSION AND RESULT

Abstract
Obstacle avoiding robot was designed, constructed and programmed
which may be potentially used for educational and research purposes.
The developed robot will move in a particular direction once the infrared
(IR) and the PIR passive infrared (PIR) sensors sense a signal while
avoiding the obstacles in its path. The robot can also perform desired
tasks in unstructured environments without continuous human
guidance. The hardware was integrated in one application board as
embedded system design. The software was developed using C++ and
compiled by Arduino IDE 1.6.5. The main objective of this project is to
provide simple guidelines to the polytechnic students and beginners
who are interested in this type of research. It is hoped that this robot
could benefit students who wish to carry out research on IR and PIR
sensors.

The project provides a guideline to the students who are new in the world of
Arduino and help them to understand about embedded system, IR sensors,
microcontroller and how to make a robot using Arduino. The thesis will make
students learn more about basic knowledge and skills regarding servo, program
and mathematics to calculate program values. New students will learn how to
program the BOE-Bot to perform basic maneuvers and gradual acceleration and
deceleration of the robot to get robot out of maneuvers and also students will
learn to write subroutines to perform basic maneuvers.
Robotics is the branch of technology that deals with the design, construction,
operation, and application of robots. A machine capable of carrying out a complex
series of actions automatically, esp. one programmable by a computers is defined
as a robot. And, Obstacle avoidance refers to the ability of a robot to detect
obstacles in its way if there are any and thus make its own obstacle free path.
INTRODUCTION

MOTOR DRIVE MODULE (L298D)
SERVO MOTOR JUMPER WIRE
BREADBOARD DC motors
WHEELS

17
Arduino
Arduino is an open-source electronics platform based on hardware and software. Arduino has done
more than thousand of projects. It has uses for notification, emergency beam etc.
Arduino was designed at the Ivrea Interaction Design Institute(2005) as an easy tool for fast prototyping,
can be used for students without a background in electronics and programming.
Parallax Basic Stamp, Net media's BX-24, Phidgets, MIT's Handy board, and many others offer similar
functionality. But Arduino was preferred by developers due to
Inexpensive
Cross-platform
Simple, clear programming environment
Open source and extensible software
Open source and extensible hardware

18
Arduino UNO
Arduino Board-Arduino Uno
Voltage Processor-5V 16MhzATmega328
Memory- 2KB SRAM,32KB flash
Digital I/O-14
Analogue I/O-6 inputs, 0 output
32 KB of flash memory
Arduino Uno differs from other preceding boards due to its features which include
ATmega8U2 that is programmed as a USB-to-serial. Arduino Uno may be powered either
through the USB connection or using an external power supply.
Arduino Uno has been named to mark the new Arduino 1.0 where version 1 and Uno will
be the reference model for the Arduino platform.
Arduino UNO
Vin Voltage from Ext. Power jack
5V-5V output from on-board Voltage regulator chip
3.3V-3.3V output from on-board Voltage regulator chip
Gnd-3 pins
IOREF-Tied to 5V, tells Arduino shields voltage level from which Arduino board operates
Reset-From Reset pin on MCU, tied to VCC through 10K resistor, pull to GND to reset

19
Ultrasonic Sensor
ULTRA = BEYOND
SONIC = SOUND The sound beyond human hearing range(20000Hz) is known as ultrasonic.
An Ultrasonic sensor is a device that can measure the distance to an object by using sound
waves. It measures distance by sending out a sound wave at a specific frequency and
listening for that sound wave to bounce back. By recording the elapsed time between the
sound wave being generated and the sound wave bouncing back, it is possible to calculate the
distance between the sonar sensor and the object.
The HC-SR04 ultrasonic sensor uses sonar to determine distance to an object like bats do. It
offers excellent non-contact range detection with high accuracy and stable readings in an
easy-to-use package. From 2cm to 400 cm or 1” to 13 feet. Its operation is not affected by
sunlight or black material like sharp rangefinder. It comes complete with ultrasonic transmitter and
receiver module.
Sound travels through air at about 344 m/s , you can take the time for the sound wave to return and
multiply it by 344 meters (or 1129 feet) to find the total round-trip distance of the sound wave.
Round-trip means that the sound wave traveled 2 times the distance to the object before it was
detected by the sensor; it includes the trip from the sonar sensor to the object and the trip from the
object to the Ultrasonic sensor. To find the distance to the object, simply divide the round-trip
distance in half.

20
DISTANCE=SPEED OF SOUND*TIME TAKEN/2
VCC-The VCC pin powers the sensor, typically with +5V
Trigger-Trigger pin is an Input pin. This pin has to be kept high for 10us to initialize measurement by
sending US wave.
Echo-Echo pin is an Output pin. This pin goes high for a period of time which will be equal to the time
taken for the us wave to return back to the sensor.
Ground-This pin is connected to the Ground of the system
The ultrasonic sensor emits the short and high frequency signal. These propagate in the air at the
velocity of sound. If they hit any object, then they reflect back echo signal to the sensor. The
ultrasonic sensor consists of a multi vibrator, fixed to the base. The multi vibrator is combination of
a resonator and vibrator. The resonator delivers ultrasonic wave generated by the vibration. The
ultrasonic sensor actually consists of two parts; the emitter which produces a 40kHz sound wave
and detector detects 40kHz sound wave and sends electrical signal back to the microcontroller.

21
HC-SR04 Ultrasonic Sensor - Applications
➢ Used to avoid and detect obstacles with robots like biped robot, obstacle avoider
robot, path finding robot etc.
➢ Used to measure the distance within a wide range of 2cm to 400cm
➢ Can be used to map the objects surrounding the sensor by rotating it
➢ Depth of certain places like wells, pits etc. can be measured since the waves can
penetrate through water

22
L298D Motor Driver Shield
L293D is a monolithic integrated, high voltage, high current, 4-channel driver. Basically, this
means using this chip we can drive DC motors with power supplier up to 36 Volts, and the
chip can supply a maximum current of 600mA per channel. L293D chip is also known as a
type of H-Bridge. The H-Bridge is typically an electrical circuit that enables a voltage to be
applied across a load in either direction to an output. E.g. motor.
L298D Motor Driver Shield – Features
➢ 2 connections for 5V 'hobby' servos connected to the Arduino's high-resolution
dedicated timer - no jitter
➢ Up to 4 bi-directional DC motors with individual 8-bit speed selection
➢ Up to 2 stepper motors with single coil, double coil, interleaved or micro-stepping.
L298D Motor Driver Shield – Application
➢ It is used in Robotics projects requiring stepper motor interface.
➢ Multiple DIY projects.

23
SG-90 Servo Motor
A servo motor is an electrical device which can push or rotate an object with great precision.
If we want to rotate and object at some specific angles or distance, then we use servo motor. It
is just made up of simple motor which run through servo mechanism. If motor is used is DC
powered then it is called DC servo motor, and if it is AC powered motor then it is called AC
servo motor. We can get a very high torque servo motor in a small and light weight packages.
Doe to these features they are being used in many applications like toy car, RC helicopters and
planes, Robotics, Machine etc. The position of a servo motor is decided by electrical pulse and
its circuitry is placed beside the motor.
Servo Motors – Controlling
Servo motor is controlled by PWM (Pulse width Modulation) which is provided by the control
wires. There is a minimum pulse, a maximum pulse and a repetition rate. Servo motor can
turn 90 degrees from either direction form its neutral position. The servo motor expects to see
a pulse every 20 milliseconds and the length of the pulse will determine how far the motor turns. For
example a 1.5ms pulse will make the motor turn to the 90° position, such as if pulse is shorter than
1.5ms shaft moves to 0° and if it is longer than 1.5ms than it will turn the servo to 180°. Servo motor
works on PWM (Pulse width modulation) principle, means its angle of rotation is controlled by the
duration of applied pulse to its Control PIN.

24
Servo Motors – Applications
➢ Robotics
➢ Animatronics
➢ Radio Control Cars/Boats/Planes
Servo Motors – Advantages
➢ Low cost - Smaller sized servos can be purchased for just a few dollars.
➢ Variety - There is a wide range of sizes and torque ratings
➢ Simple to control - using logic level pulses from a microcontroller or a dedicated servo controller
DC Motor – Overview
A Direct Current (DC) motor is a rotating electrical device that converts direct current, of
electrical energy, into mechanical energy. An Inductor inside the DC motor produces a
magnetic field that creates rotary motion as DC voltage is applied to its terminal. Inside the
motor is an iron shaft, wrapped in a coil of wire. This shaft contains two fixed, North and
South, magnets on both sides which causes both a repulsive and attractive force, in turn,
producing torque.

25
CONTROL
The servos rotate in one direction when the power is supplied to its terminal. If the power is
supplied into the reverse polarity, the robot will move to the opposite direction
The driving system in the project is differential driving system. In this system, the wheels are
rotated at different speeds resulting in the robot rotating right or left. That is why it is called
Differential Drive. For example, the robot will turn right if the left wheel rotates faster than right
wheel.
MOTION RIGHT Wheel Left Wheel
FORWARD Clockwise Counter Clockwise
BACKWARD Counter Clockwise Clockwise
Rotate RIGHT Counter Clockwise Counter Clockwise
Rotate LEFT Clockwise Clockwise
So moving and steering the Robot is just a matter of controlling the two direct current (DC)
motors of the robot

26
Motor A
Clock Wise(CW) : Input A = High and Input B is Low
Counter Clock Wise(CCW) : Input A = Low and Input B is High
Stop: Input A= High and Input B is High
Stop: Input B=Low and Input B is Low
Motor B
Clock Wise(CW) : Input C= High and Input D is Low
Counter Clock Wise(CCW) : Input C = Low and Input D is High
Stop: Input C= High and Input D is High
Stop: Input C=Low and Input D is Low

27
Robot working principle
The robot uses the Ultrasonic distance sensor to measure the distance in front of it. When this
distance reduces to a particular level, the robot interprets it to mean the presence of an
obstacle in its path. When the robot detects an obstacle in its path, it stops, goes backward for
a few cm, looks around (right and left) then turn towards the direction that shows more free
space in front of it.
STEP 1:
Connect the motor and wheels to the chassis.
• To complete this step, we start by soldering the thick red and black wires to the positive and negative
terminals of the motors
• Attach the front wheel
• Attach the rear wheels to the chassis
STEP 2:
Prepare the Switch and connect the Power Source
We add a switch to the battery holder so that we will be able to turn the robot on or off. The switch is
connected according to the schematics shown below and attached to the case using a hot glue. The Battery
case is attached to the chassis using a double-sided tape to ensure everything sticks together.

28
Step 3.
Installation the others parts of the robot
This step is to mount other parts of the robot before we start connecting their wires. The
motor shield is stacked on the Arduino and it is mounted on the chassis using a double-sided
tape. The current requirements of the motors are often higher than what the Arduino can
provide, that is why it’s important to use the motor shield as it is equipped with additional
circuitry to provide up to 600mA current to each of the motors. This shield provides power to
the motors and the servo motor and ultrasonic sensor and makes it much easier. The
Ultrasonic sensor is also mounted on the top of the servo motor which is then mounted on the
chassis using some screws.
Step 4.
Wire up the components
Wire up the components together.

29
Ultrasonic Sensor -Motor Shield(connection)
• VCC - 5v
• Gnd - Gnd
• Trig -A4
• Echo - A5
Servo - Motor Shield (Servo 2 port)
• Signal (yellow wire) - S
• Vcc(Red wire) - +
• Gnd(Blow wire) --
DC motors - Motor Shield
• Left Motor -M1
• Right Motor -M2
CONNECTIONS

30
The controller board is used to communicate with the PC using serial communicator (USB
connection). The data is transferred between them bit by bit. An adaptor is used to supply
power to the controller board and a USB programmer is used to burn the hardware program
into the Arduino board. The Arduino integrated development environment (IDE) is a cross-platform
application (for Windows, macOS, Linux) that is written in the programming language Java.
PROGRAMMING THE ROBOT
Servo System Coding
Sensor System Coding
Arduino coding
USED ADURINO IDE APP(SKETCH) FOR CODING TO ADURINO.
AVAILABLE FREE IN MISCROSOFT STORE

34
The piezoelectric element is a crystal that changes its shape slightly when voltage is applied
and upon the high and low voltage applied at a rapid rate, piezoelectric crystal changes
rapidly in shape with vibration resulting in the production of the sound due to the vibration of
the air caused by piezo speaker

38
APPLICATION OF OBSTACE AVOIDANCE ROBOT
Obstacle avoiding robots can be used in almost all mobile robot navigation
systems.
They can be used for household work like automatic vacuum cleaning.
They can also be used in dangerous environments, where human penetration
could be fatal.

40
Block Diagram of Hardware
Sensor
Power Supply
Arduino Uno
Motor Driver
Power Supply
Left DC
Motor
Right DC
Motor
Servo Motor

43
SENT PULSE(ping)
RECEIVED PULSE(Echo)
TRIG-Toggle to start ECHO-Pulse high until returns

44
20ms
1.5ms
2ms
1ms
0 Degree
90 Degree
180 Degree
Position of motor shaft when PWM is generated

46
METHODOLOGY ON FLOWCHAT THAT HOW IT WORKS

RESULT
The outcome of the thesis is a simple, PC-controlled robot controlled which moves around detecting
the obstacles on its way and thus making its way through the free space avoiding all the obstacles it
encounters. After the completion of the robot, the robot can now emit IR ray through the IR emitter,
and the IR receiver will detect receive the bounced IR ray that strikes the obstacles if there are any. If
there are any obstacles and IR collides with them, then brain of the robot (micro controller) will
calculate the distance.
The robot is made activated after the switch on the activity board is turned on. If there seems to have
any obstacle with in the distance set to it, it will move to the opposite direction of the obstacle
detected. That is, if the right sensor detects the object on its way, it will turn left and start moving
straight again and if left sensor detects an obstacle, it will turn right and continue moving. Additionally,
if there seems to be obstacle all around the robot within the detection distance, robot will keep on
rotating 360°.
After the project, students can design alternative technical solutions based on existing requirement
specifications. They can independently and proactively analyze and solve complex technical
challenges, as well as to study and evaluate the solution proposals of others which will develop
knowledge, skills and attitudes

CONCLUSION
Today we are in the world of robotics. Knowingly or unknowingly, we have been using different types of
robots in our daily life. The aim of the thesis is to evaluate what students can learn about the fields of
engineering, mechatronics, and software development as they design, construct, and program an
autonomous robot. This will to provide a guideline to the students who are new in the world of Arduino and
help them to understand about embedded system, IR sensors, microcontroller and how to make a robot
using Arduino.
The above Arduino controller and ultrasonic sensor were studied and the HcSR-04 ultrasonic sensor was
selected, as the controlling result are satisfying for its use in the automobile prototype system bring
developed. It was used to sense the obstacle and avoidance them. On successful implementation of
obstacle avoidance algorithm was successfully carried out too with minimal errors, by coding the algorithm
in python. Obstacle avoidance is a very good application to be used in vehicle preventing many accidents
and loss of life.

ALL SIMULATION,PRESENTATION HARDWARE COMPONENTS ARE DONE BY ME DUE TO MY PARTNER’S
ABSENT(DUE TO DISCONTINUATION OF COLLEGE).
ALL THE EXPERIMENT,SIMULATIONS AND READINGS HAS BEEN DONE IN THIS PROJECT MAM

OBSTACLE AVOIDACE ROBOT USING ARDUINO UNO AND ULTRASONIC SENSOR

More Related Content

What's hot

Similar to OBSTACLE AVOIDACE ROBOT USING ARDUINO UNO AND ULTRASONIC SENSOR

Recently uploaded

OBSTACLE AVOIDACE ROBOT USING ARDUINO UNO AND ULTRASONIC SENSOR