PROJECTREPORTON
“speed And Direction control of dc motor using
android mobile application “
Submitted in partialfulfilment of requirement for the award
of degree of B.TECH. in ELECTRICAL ENGINEERING
Submitted by : Chandan Kumar (1501001D)
Arjun Kumar Singh (1401040)
Vivekanand Sardar (1501020D)
Prakash Dey (1401041)
Rahul kumar (1401036)
under the guidance of
prof -REKHA JHA MAM
Dept of ELECTRICAL ENGG. BIT SINDRI DHANBAD 828123

CERTIFICATE
This is certify that the project “speed And Direction control of dc
motor using android mobile application “
has been submitted by
1. Chandan Kumar (1501001D)
2. Arjun Kumar Singh (1401040)
3. Vivekanand Sardar (1501009D)
4. Prakash Dey (1401041)
5. Rahul kumar (1401036)
Partial fulfillment of award of B.Tech (7th
sem) in
Electrical Engineering Vinoba Bhave University
Hazaribag is a bonafied work carried out by them
under my guidance.
Prof. Rekha Jha Mam Prof. Pankaj Rai
(supervisor) Head of Department
Electrical Engg. BIT SINDRI
Examined and approved
External examiner

ACKNOWLEDGEMENT
I sincerely take this opportunity to express my thanks and deep gratitude to all
who extended hearted co-operation opinion and gracious hospitality to me in
completing this work. It is my immense pleasure to be work under the guidance
of Prof. Rekha Jha Mam, Dept. of Electrical Engineering, B.I.T.SINDRI. I am
very grateful to her for being incredible supportive throughout the project work
and her exhaustive guidance and patience she had while listening my approaches.
I owe my greatest debt to Prof. (Dr.) Pankaj rai, (Head of the EE Dept.) B.I.T.
SINDRI for his advice and for providing necessary facility for my work.
I thank to all Electrical engineering faculty members, my group members,
Librarian including my friends for their encouragement, cooperation and needful
support at different times during this work.
I gratefully acknowledge my sincere thanks to my family members, specially my
parents for their inspirational impetus and moral supportduring the courseof this
work and whole tenure of my stay in B.I.T. SINDRI.
Lastly, I want to thank all those who helped me directly or indirectly in the
completion of my dissertation work.
NAME ROLL NO.
1. Chandan Kumar (1501001D)
2. Arjun Kumar Singh (1401040)
3. Vivekanand Sardar (1501020D)
4. Prakash Dey (1401041)
5. Rahul kumar (1401036)
Place:
Date:

CONTENTS
Sr.No. Title Page no.
1. Abstract
2. Introduction
3. Block Diagram
4. systemArchitecture
5. Working
6. Software Simulation
7. Android Studio
8. Arduino UNO
9. BluetoothModule
10. L298 MotorDiver IC Circuit
11. DC Motor
12. Advantage
13. Application
14. Projectprogress report
15. References
1.
1
.

1.ABSTRACT
Today most widely used systems are wireless because these systems
are less in cost and more efficient than wired systems. In wireless
systems we do not use wires so these systems are light in weight and
free from line losses i.e. losses due to current flowing in the wires.
Wires are easily affected by environmental conditions, so wired
systems are not so good. In wireless systems, the data transmitted
through the Electromagnetic Waves and these waves are not affected
by the environmental conditions. Also the environment is not affected
by these waves. Hence this is an eco-friendly method. Today motors
are everywhere. In every industry motors are playing a great role. In
home appliances motors are playing a common role. So the us e of this
project will reduce a number of wires which are being used daily.
2
3.

Moreover, the reduction in number of wires will reduce the electrical
losses.
The Android-is the most popular mobile platform, which is very useful
in creating much real time application which is useful in our day to day
life. The DC motors are widely used for variable speed drive system in
industrial applications such as industrial automation, electric traction,
aircraft, military equipment, hard disk drives because of their high
efficiency, silent operation, compact, reliability and low maintenance.
Due to the advancement of wireless technology, there are several
connections introduced such as GSM, Wi-Fi, ZIGBEE and Bluetooth.
Each of the connection has their own unique specifications and
applications. Among these wireless connections, Bluetooth technology
is often implemented. The speed control was implemented using
Bluetooth technology to provide communication access from smart
phone. On the other hand we have ARDUINO UNO platform that we
can use to quickly prototype electronic systems. Android mobile act as
a transmitter and the received by Bluetooth receiver interfaced to
Arduino which send data to the Bluetooth module and which in-turn
run the motor
Keywords: ARDUINO, Android mobile, DC Motor, Bluetooth
module

2.INTRODUCTION
This project is all about the wireless operation of a DC Motor. In this project, we will
control the speed of a DC Motor. Direction of the rotation will also be controlled.
Wireless facility is provided with the help of Bluetooth connectivity. An android
handset is required to control the operation. As the name suggests that “Speed and
Direction Control of DC Motor using Android Mobile Application” is controlling
the speed of a DC motor with any mobile phone containing some medium of
connectivity such as Bluetooth. Various terms related to this project can be discussed
as follows. Since we are concern with the wireless application that is why we are using
here a mobile phone to control the whole process. Now the question is why should we
use a mobile phone? Which is the most suitable mobile phone? So the answer is that
mobile is used only for a Bluetooth connection. We need not to carry an extra device
for transmitting the data. This transmitter is already inbuilt in a mobile phone. Now
come with the question of most suitable mobile phone, so it can be observed that
Android phones are the most widely used phones. Android phones are very easy from
the operating point of view. I-phones and windows phones are not as popular as the
Android phones. So the Android phone will be used here.
Today most of the industries use DC motors. So, speed controlling of DC motors plays
a very vital role. Therefore, our paper concentrates on monitoring and controlling the
speed of DC motor using Android mobile application, with the help of Bluetooth
technology. Smart phones have in-1built Bluetooth technology, so and external
Bluetooth module is interfaced with the microcontroller unit (ARDUINO) for wireless
communication. The Bluetooth module receives command from the mobile phone
android application. So, according to the input signal, with the help of arduino,
MOSFET can be used to vary the voltage as well as the speed of the DC motor using
PWM technique. Direction of the DC motor can also be varied with the help of relay
circuit or H-Bridge network.
4.

3.BLOCK DIAGRAM
Fig. Block Diagram
5.

4. SYSTEM ARCHITECTURE
Fig. IILSYSTEM ARCHITECTURE
6.

5.WORKING
Signal from Android device will be sent through Bluetooth. This
signal will be communicated with Arduino with the help of
transmitter and receiver of both the devices. This signal will be
represented by a single letter which denotes the speed and
direction of the motor. There are three different direction of
rotation: clockwise, anti-clockwise and stopping of the motor and
these will be represented by different letters. This letter will vary
the speed with reference to the Arduino code. For forward
direction the transistor Q1 and Q4 will be ON and for the reverse
direction Q2 and Q3 will ON. Q1 and Q2 are PNP transistors
which becomes ON when low signal is sent and Q3 and Q4 are
NPN transistors which becomes ON when high signal. PWM pins
5 and 6 are used to control the speed of the in both directions, they
use the concept of varying the duty cycle (PWM Technique).
Duty cycle varies from 0 - 225. So by choosing different duty
cycle speed can be varied. Direction is controlled with the concept
of having H-Bridge.
7.

6.SOFTWARE SIMULATION
The android application in the mobile phone is developed with the
help of Android Studio Software.
6.1 ANDROID STUDIO
Android Studio is a free integrated development environment (IDE)
from Google and official development environment for Android.
Android Studio is based on IntelliJ IDEA. In addition to the features
that are already implemented in IntelliJ IDEA, furthermore, the
following functions are available: Support for the development of
Android, Android Wear and Android TV Apps Android Studio uses a
build management automation tool, the on Griddle is based. The
system gives the developer the opportunity for different device types
such. B. Tablets to create optimized versions of the app. Theme editor
Android Lint It is possible to configure Google services like Google
Cloud Messaging within the IDE and apply it directly to the app.
Support for Pro-Guard and automatic app signing The source code of
Android studio is freely available
8.

The major elements of block diagram are:
 Arduino UNO
 Bluetooth Module
 DC motor
 L298 motor driver IC cicuit
6.2ARDUINO UNO
The Uno is a microcontroller board based on the ATmega328P. It has 14 digital input/output
pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz quartz crystal, a
USB connection, a power jack, an ICSP header and a reset button. The ATmega328 on the Uno
comes pre-programmed with a boot loader that allows you to upload new code to it without the
use of an external hardware programmer.
TECH SPECS:
Microcontroller ATmega328P
9
.

Operating Voltage 5V
Input Voltage (recommended) 7-12V
Input Voltage (limit) 6-20V
Digital I/O Pins 14 (of which 6 provide PWM output)
PWM Digital I/O Pins 6
Analog Input Pins 6
DC Current per I/O Pin 20 mA
DC Current for 3.3V Pin 50 mA
Flash Memory 32 KB (ATmega328P) of which 0.5 KB used by bootloader
SRAM 2 KB (ATmega328P)
EEPROM 1 KB (ATmega328P)
Clock Speed 16 MHz
LED_BUILTIN 13
Length 68.6 mm
Width 53.4 mm
Weight 25 g
Fig. Arduino Uno
10.

BLUETOOTHMODULE
Bluetooth serial communication module has two work modes: order-response work mode and
automatic connection work mode. And there are three work roles at the automatic connection
work mode. When the module is at the automatic connection work mode, it will follow the
default way set lastly to transmit the data automatically. When the module is at the order
response work mode, user can send the AT command to the module to set the control
parameters and sent control order. The work mode of this Module can be switched by
controlling the module PIN (PIO11) input level. In this project Bluetooth module is used to
send signals from the ARDUINO UNO.
Fig. Bluetooth module. Fig. Bluetooth serial communication with Ardunio uno
DC MOTOR
Electrical motors are everywhere around us. Almost all the electro-mechanical movements we
see around us are caused either by a AC or a DC motor. Here we will be exploring DC motors.
This is a device that converts DC electrical energy to a mechanical energy.
13
..

PRINCIPLE OF DC MOTOR
This DC or direct current motor works on the principal, when a current carrying conductor is
placed in a magnetic field; it experiences a torque and has a tendency to move.
This is known as motoring action. If the direction of current in the wire is reversed, the direction
of rotation also reverses. When magnetic field and electric fild interact they produce a
mechanical force, and based the working principle.
The direction of rotation of a this motor is given by Fleming’s left hand rule, which states that if
the index finger, middle finger and thumb of your left hand are extended mutually
perpendicular to each other and if the index finger represents the direction of magnetic field,
middle finger indicates the direction of current, then the thumb represents the direction in which
force is experienced by the shaft of the DC motor.
Structurally and construction wise a direct current motor is exactly similar to a DC generator,
but electrically it is just the opposite. Here we unlike a generator we supply electrical energy
to the input port and derive mechanical energy from the output port. We can represent it by the
block diagram shown below;
14
.

Here in a
DC motor, the supply voltage E and current I is given to the electrical port or the input port and
we derive the mechanical output i.e. torque T and speed ω from the mechanical port or output
port.
The input and output port variables of the direct current motor are related by the parameter
K. So from the picture above we can well understand that motor is
just the opposite phenomena of a DC generator, and we can derive both motoring and
generating operation from the same machine by simply reversing the ports.
To understand the DC motor in details let’s consider the diagram shown below,
The direct current motor is represented by the circle in the centre, on which is mounted the
brushes, where we connect the external terminals, from where supply voltage is given. On the
mechanical terminal we have a shaft coming out of the Motor, and connected to the armature,
and the armature-shaft is coupled to the mechanical load. On the supply terminals we represent
the armature resistance Ra in series. Now, let the input voltage E, is applied across the brushes.
15.

Electric current which flows through the rotor armature via brushes, in presence of the magnetic
field, produces a torque Tg. Due to this torque Tg the dc motor armature rotates. As the armature
conductors are carrying currents and the armature rotates inside the stator magnetic field, it
also produces an emf Eb in the manner very similar to that of a generator. The generated Emf
Eb is directed opposite to the supplied voltage and is known as the back Emf.
SPEED CONTROL OF DC MOTOR
Speed control means intentional change of the drive speed to a value required for performing
the specific work process. Speed control is a different concept from speed regulation where
there is natural change in speed due change in load on the shaft. Speed control is either done
manually by the operator or by means of some automatic control device. One of the important
features of DC motor is that its speed can be controlled with relative ease. We know that the
emf equation of DC motor is given as,
Therefore, N = 60A E / PZØ
N = E / kØ
where, k = PZ/60A
N = V - Ia Ra / kØ
Therefore, speed (N) of 3 types of DC motor – SERIES, SHUNT and COMPOUND can be
controlled by changing the quantities on RHS of the expression. Therefore, speed can be varied
by changing
1. Terminal voltage of the armature V.
2. External resistance in armature circuit Ra.
3. Flux per pole φ.
16
..

The first two cases involve change that affects armature circuit and the third one involves
change in magnetic field.
Therefore, speed control of DC motor is classified as
1. Armature control methods
2. Field control methods.
Speed Control of DC Series Motor
Speed control of DC series motor can be done either by armature control or by field control.
Armature Control of DC Series Motor:
Speedadjustment of DC series motor by armature controlmay be done by any
one of the methods that follow,
Armature Resistance Control Method:
This is the most common method employed. Here the controlling resistance is connected
directly in series with the supply of the motor as shown in the fig.
The power loss in the control resistance of DC series motor can be neglected because this
control method is utilized for a large portion of time for reducing the speed under light load
condition. This method of speed control is most economical for constant torque. This
method of speed control is employed for DC series motor driving cranes, hoists, trains etc.
17
.

Shunted Armature Control:
The combination of a rheostat shunting the armature and a rheostat in series with the
armature is involved in this method of speed control. The voltage applied to the armature is
varies by varying series rheostat R1. The exciting current can be varied by varying the
armature shunting resistance R2. This method of speed control is not economical due to
considerable power losses in speed controlling resistances. Here speed control is obtained
over wide range but below normal speed.
Armature Terminal Voltage Control:
The speedcontrol of DC series motor can be accomplished by supplying the power to
the motor from a separate variable voltage supply. This method involves high cost so it
rarely used.
Field Control of DC Series Motor:
The speed of DC motor can be controlled by this method by any one of the
following ways –
1. Field Diverter Method:
This method uses a diverter. Here the field flux can be reduced by shunting a portion of
18.

motor current around the series field. Lesser the diverter resistance less is the field current,
less flux therefore more speed. This method gives speed above normal and the method is
used in electric drives in which speed should rise sharply as soon as load is decreased.
2. Tapped Field Control:
This is another method of increasing the speed by reducing the flux and it is done by
lowering number of turns of field winding through which current flows. In this method a
number of tapping from field winding are brought outside. This method is employed in
electric traction.
19.

ADVANTAGES
1. Bluetooth consumes less power than other devices.
2. Android application is user-friendly.
3. Technically expert persons are not required.
4. Wireless communication is enhanced.
5. Programming is simpler.
APPLICATIONS
1. Can be used in simple robotic application to control direction and
speed of signal motor.
2. Many industrial applications require adjustable speed drive and
constant speed for improving the quality product.
3. The circuit shown here control a signal dc motor but can be
extended to control two motors with independent speed and
direction controls.
4. Home automation
20.

PROJECT PROGRESS REPORT
We have studied this latest technology of speed and direction
control of DC Motor and also gone through the various
equipment needed to implement in this project .We also came
to know that we can control the speed and direction control of
DC Motor using Android Application .We also studied about
the programing for Arduino and we found that this system for
controlling of DC Motor finds application in home automation,
Many industrial applications require adjustable speed drive,
Intensity of light can also be controlled with the help of android
app. We have also studied the software simulation, Block
diagram, Architecturefor the speed and direction control of DC
Motor using Android application.
REFERENCES
[1]. Abhishek Gupta: Induction motor speed control using
android application.ISSN-2348-6988 International Journal of
Electrical and Electronic ResearchVolume 4 Issue 2 April-june
2016.
[2]. Salivahanan , S.Suresh, and Vallavaraj,- A. “Electronic
Devices and Circuit”, Fourth Edition, Tada Seventh Edition,
2000, McGraw-Hill Publishing Company Limited.
[3]. Youtube –nevon project
[4]. Rekha jha mam
L298N motor driver IC circuit :
21.
22
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11

Most of the microcontrollers operate on very low voltage (5v) and current while
the motors require higher voltages and current So, the microcontrollers cannot
provide them such higher current. For this purpose, we use motor driver ICs.
Motor driver is a little current amplifier. It takes a low current signal and gives
out a high current signal, which can drive a motor. It can also controlthe direction
of motor. Motor drives are of many kind depending upon the maximum supply
voltage, maximum output current, rated power dissipation, load voltage and
number outputs etc. Here we are going to discuss motor driver L298N. It is used
in dc motor speed control project and you can interface dc motor easy with
microcontroller using this motor driver.
Features of L298 motor driver:
L298N is an integrated circuit multi watt 15 package and capable of giving high
voltage. It is a high current dual full-bridge driver, which is designed as to accept
standard TTL logic levels. It can drive inductive loads e.g. relays, solenoids,
motors (DC and stepping motor) etc.
Its basic features are:
 Maximum supply voltage 46V
 Maximum output DC current 4A
 Low saturation voltage
 Over temperature protection
 Logical “0” Input Voltage up to 1.5 V

PIN DIAGRAM of L298N motor driver:
The pin diagram in top view for L298N is given below:
L298N motor driver internal circuit:
12.
2.
13.

PIN DESCRIPTION of L298N motor driver:
L298N consists of four independent power amplifiers. Two of them form H-bridge A while
other two form H-bridge B. One H bridge is used to switch the polarity in controlling direction
of DC motor. Pair of H Bridge is used to control a bi-polar stepper motor.
 Amp A1 and A2 => H Bridge A
 Amp B1 and B2 => H Bridge B
Basically L298N is used to drive inductive or magnetic loads, so there can come voltage spikes
in output. To avoid that voltage spikes there should be some internal parasitic or Flywheel
diodes. But it lacks them. We use externally these flywheel diodes. They can be 1N5819
schottky diodes or 1N4001 rectifier diodes.
Each bridge is provided with enable pins (ENA, ENB) and current sense pins (CSA, CSB).
Current sense pins can be tied to ground but we can also insert low value resistor and its voltage
reading is proportional to current. Both enable pins can be used at the same time which makes
all for outputs active at the same time. All the four inputs and Enable pins work on 5v TTL
logic which makes the connection easy with microcontrollers.
14.
.

 ENA=5v, High logic (Amplifier A1 and A2 on)
 ENA=0v, Low logic (Amplifier A1 and A2 off)
 ENB=5v, High logic (Amplifier B1 and B2 on)
 ENB=0v, Low logic (Amplifier B1 and B2 off)
Circuit diagram of L298N motor driver:

Motivation
As digitalisation is taking over the world. Everything is now
controlledwirelessly. Keeping thisthing inmind we decidedto
work on the ideaof drivinga dc motor using a PWM technique
and controlling it using the ANDROID platform.
After discussing this with our concerned mentors we found
that thisideaisa intiativetowardsthe home automationusing
mobile device which is very common thing now , as nearly
every hand bears the same and is cheap.
And now there are many apps(softwares) that are publiclyon
internet free of cost .