Remote control of home appliances via bluetooth using Arduino

1. 1
Remote Control of Home Appliances using
Smartphone
By
SARBARI DAS (ROLL NO: 16900513039)
SHABNAM AFRIN (ROLL NO: 16900513042)
SHUBHAM BHATTACHARYA (ROLL NO: 16900513043)
SIDDHARTHA MISHRA (ROLL NO: 16900513044)
JINIA BISWAS (ROLL NO: 16905514039)
AYANBASU (ROLL NO: 16900512015)
Under the guidance of
PROF. SMARAJITMAITY
Department of Electronics and Instrumentation Engineering
Academy Of Technology, Adisaptagram
Project Report
Submitted in partial fulfillment of requirement for the Degree of
Bachelor of Technology
ACADEMY OF TECHNOLOGY,
AEDCONAGAR, HOOGHLY-712121
WEST BENGAL, INDIA

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ACKNOWLEDGEMENT
First and foremost, we would like to thank to our
supervisor of this project, Prof. SmarajitMaity for the
valuable guidance and advice. He inspired us greatly to
work in this project. His willingness to motivate us
contributed tremendously to our project. We also would
like to thank him for showing us some example that related
to the topic of our project. Besides, we would like to thank
the authority of Academy of Technology (AOT) for providing
us with a good environment and facilities to complete this
project. Finally, an honorable mention goes to our families
and friends for their understandings and supports on us in
completing this project. Without helps of the particular that
mentioned above, we would face many difficulties while
doing this.
SARBARI DAS SHABNAM AFRIN
SHUBHAM BHATTACHARYA SIDDHARTHA MISHRA
JINIA BISWAS AYAN BISWAS

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Department of Electronics and IntrumentationEngineering
Academy of Technology, Adisaptagram
CERTIFICATE
This is to certify that
SARBARI DAS (ROLL NO: 16900513039)
SHABNAM AFRIN (ROLL NO: 16900513042)
SHUBHAM BHATTACHARYA (ROLL NO: 16900513043)
SIDDHARTHA MISHRA (ROLL NO: 16900513044)
JINIA BISWAS (ROLL NO: 16905514039)
AYANBASU (ROLL NO: 16900512015)
have undergone the live project on Remote Control of Home Appliances using
Smartphones and have prepared this project report by virtue of their Diligence and
self-effort.
They have successfully completed every aspect of this project with a lot of sincerity
while abiding with the rules of the institution.
We wish them all success for their future
_______________________ ___________________________
Prof. Smarajit Maity Prof. Hiranmoy Mandal
(Project Guide) (Head of Dept.)

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Table of Contents
Chapter 1: Introduction………………………………………………………………..6
Chapter 2: Literature Survey…………………………………………………………9
2.1: GSM based home automation……………………………………………..9
2.2: IR remote controlled home automation………………………………..11
2.3: DTMF based home automation………………………………………….14
2.4: RF based home automation………………………………………………16
Chapter 3: Previous Project work……………………………………………18
3.1: Component specification………………………………………………….18
3.2: Hardware description……………………………………………………..20
3.3: Software description……………………………………………………….22
3.4: Implementation of arduino on breadboard…………………………..25
3.5: Checking our arduino circuit……………………………………………31
Chapter 4: Project Work…………………………………………………….35
4.1: Introduction………………………………………………………………….37
4.2: Block diagram………………………………………………………………38
4.3: Circuit diagram…………………………………………………………….39
4.4: Flowchart ……………………………………………………………………42
4.5: Program………………………………………………………………………43
Chapter 5: Result and Analysis…………………………………………..47
5.1: Truth table………………………………………………………………….47
5.2: Snapshot and screenshots of the project…………………………….48
5.3: Merits…………………………………………………………………………50
5.4: Demerits……………………………………………………………………..51
5.5: Future scope………………………………………………………………..51
Chapter 6: Reference………………………………………………………..53

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CHAPTER-1
INTRODUCTION

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CHAPTER-1
INTRODUCTION
In the past few years there are so many inventions in the
field of consumer electronics such as cellular phone, air
conditions, home security devices and home theaters. All
these appliances can be easily controlled by a single
controller, using personal area network in a home
environment. Busy environment and personal limitation
the market is going towards the home automation and
networking and Bluetooth is an ideal solution for this
purpose. In buildings, temperature and other electronic
devices can be easily controlled by home automation but
high degree of computer work is involved. This report
demonstrates a simple home automation system which
consists of remote mobile, host controller, and several
home appliances.
At home, we generally operate (switch on/off) all the
electrical and electronics appliances such as fan, light,
cooler, air conditioner, and so on through switches of the
regular switch board. This manual switching of any home
appliance is an inconvenient method for physically disabled
or elders or even for normal young guys when frequent
switching operation is required.
Thus, this conventional manual switching method has to
be overcome by an easier method of switching. This can be
done using an advanced switching method like a remote
control for electronic home appliances.

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We can use the unconventional remote control technology
for controlling the home appliances easily without using
the fixed wall switch boards. There are different types of
remote control technologies such as infrared or IR remote
technology, radio frequency or RF remote control
technology, android based remote control, GSM based
remote control, DTMF based remote control, Bluetooth
remote control technology, and so on using different
wireless communication systems.

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CHAPTER-2
LITERATURE SURVEY

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CHAPTER- 2
LITERATURE SURVEY
We discuss about a few real time embedded systems based
projects with which we can design and implement remote
control circuit for home appliances.
2.1: GSM Based Home Automation
Mobile phone is a revolutionary invention of the century. It
was primarily designed for making and receiving calls &
text messages, but it has become the whole world after the
Smart phone comes into the picture. In this project we are
building a home automation system, where one can control
the home appliances, using the simple GSM based phone,
just by sending SMS through his phone. In this project, no
Smart phone is needed, just the old GSM phone will work
to switch ON and OFF any home electronic appliances,
from anywhere.
2.1.1: Working Explanation
In this project, Arduino is used for controlling whole the
process. Here we have used GSM wireless communication
for controlling home appliances. We send some commands
like “#A.light on*”, “#A.light off*” and so on for controlling
AC home appliances. After receiving given commands by
Arduino through GSM, Arduino send signal to relays, to
switch ON or OFF the home appliances using a relay
driver.

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Here we have used a prefix in command string that is “#A.”.
This prefix is used to identify that the main command is
coming next to it and * at the end of string indicates that
message has been ended.
When we send SMS to GSM module by Mobile, then GSM
receives that SMS and sends it to Arduino. Now Arduino
reads this SMS and extract main command from the
received string and stores in a variable. After this, Arduino
compare this string with predefined string. If match
occurred then Arduino sends signal to relay via relay driver
for turning ON and OFF the home appliances.
2.1.2: BLOCK DIAGRAM
Fig. 2.1.2: Block diagram of GSM based home automation.

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2.2: IR Remote Controlled Home
Automation
In this project, we are using IR based wireless
communication for controlling home appliances. In this
project, Arduino is used for controlling whole the process.
We send some commands to the controlling system by
using IR TV/DVD/MP3 remote for controlling AC home
appliances. After receiving signal from IR remote, Arduino
sends related signal to relays which are responsible for
switching ON or OFF of the home appliances through a
relay driver.
2.2.1: Working Explanation:
Working of this project is easily understandable. When we
press any button of IR Remote then remote sends a code in
form of train of encoded pulses using 38Khz modulating
frequency. These pulses are received by TSOP1738 sensor
and read by Arduino and then Arduino decodes received
train of pulse into a hex value and compares that decoded
value with the predefined hex value of the pressed button.
If any match occurs then Arduino perform relative
operation and the corresponding result is also displayed on
16x2 LCD by using appropriate commands.

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2.2.2: BLOCK DIAGRAM
Fig. 2.2.2: Block diagram of IR remote controlled home automation.

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2.3: DTMF Based Home Automation
There are two types of communication that is we generally
use - one is wired and other one is wireless. In wireless
communication we transmits signal wirelessly, like using
radio frequency (RF) and in wired communication in which
we uses wires like copper wire. In this project “DTMF Based
Home Automation System” we are going to control our
home appliances wirelessly. Other important feature of this
project is, that we are not going to use any microcontroller
in it.
2.3.1: WORKING EXPLANATION
DTMF controlled home appliances project works over
mobile DTMF technology that exists in Dial tone. DTMF
stands for Dual Tone Multiple Frequency. There are some
frequencies that we used to create DTMF tone. In simple
words by adding or mixing two or more frequencies
generates DTMF tone
When one upper and one lower frequencies mixed then a
tone is created that tone we calls Dual Tone Multiple
Frequency. In this project we control ac appliances by
pressing dial pad keys like 1, 2, 3, 4, 5 and more.

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So we can control each of the appliances according to table
output given below.
Table 2.3.1: DTMFFrequency Key Table
2.3.2: BLOCK DIAGRAM
Fig. 2.3.2: Block diagram of DTMF based home automation

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2.4: RF BASED
HOMEAUTOMATION
Radio frequency or RF remote control technology based
home automation is another technique for implementing
remote controlled home appliances. It consists of RF
transmitter circuit and RF receiver circuit.
2.4.1: WORKING EXPLANATION
The RF transmitter circuit block diagram consists of 6V
battery that provides power supply to the RF remote. 8051
microcontroller to which the load switches or switches of
home appliances are interfaced. Based on the switch or
push button pressed, the microcontroller sends commands
signals to encoder block. This data is encoded and
transmitted through the antenna of the RF transmitter.
The receiver block diagram consists of the power supply
block, 8051 microcontroller, home appliances connected to
the microcontroller through Opto-Isolators and triacs, RF
receiver interfaced to the microcontroller through the
decoder. The data receiver from the transmitter is received
by the RF receiver, decoded by the decoder and then fed to
the microcontroller. Based on the data received, the
microcontroller sends command signals to turn on or turn
off the home appliances which are here represented as
lamp loads for demonstration purpose.

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2.4.2: BLOCK DIAGRAM
Fig. 2.4.2.1: Block diagram of encoder in RF based home automation
Fig. 2.4.2.2: Block diagram of decoder in RF based home automation

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CHAPTER- 3
PREVIOUS PROJECT WORK

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CHAPTER-3
PREVIOUS PROJECT WORK
3.1: COMPONENT SPECIFICATION
1. Android Smartphone
2. Atmega 328P-PU Microcontroller
3. Bluetooth Module (HC-05)
4. Relay Driver (UCN2003A)
5. Bulb (25 Watt)
6. AC Fan
7. Arduino IDE
8. SMPS(12V, 1A)
9. Bulb Holder
10. Terminal Block
11. Crystal Oscillator(16 MHz)
12. Ceramic Capacitor(22 pF)
13. Radial Capacitor(10 microF)
14. Resistor(100 ohm, 180 ohm,1 kohm,10 kohm)
15. LED’s
16. Switch Push Button
17. Breadboard
18. Relay Switches
19. Voltage Regulator (7805)
20. Lead wires

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3.2: Hardware Description:
3.2.1: Atmega328:
ATMEGA 328 microcontroller, which acts as a processor for
the arduino board. Nearly it consists of 28 pins. From these
28 pins, the inputs can be controlled by transmitting and
receiving the inputs to the external device. It also consists
of pulse width modulation (PWM). These PWM are used to
transmit the entire signal in a pulse modulation. Input
power supply such as Vcc and Gnd are used. These IC
mainly consists of analog and digital inputs. These analog
and digital inputs are used for the process of certain
applications. The operating volt ranges from 5v. The input
voltage recommended for arduino microcontroller is from
7v and the maximum of 12v. The DC input current given to
the arduino board is in the range of 40mA.
Fig. 3.2.1: Pin configuration of 328p

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3.2.2: Switching Relay:
A relay is an electrically operated switch. Many relays use
an electromagnet to mechanically operate a switch, but
other operating principles are also used, such as solid-state
relays. Relays are used where it is necessary to control a
circuit by a low-power signal (with complete electrical
isolation between control and controlled circuits), or where
several circuits must be controlled by one signal.
Fig. 3.2.2: Switching Relay
In this project the relay have been used to control the 230V
power supply of household when connected with the
Bluetooth app.
3.2.3: Bluetooth Module:
HC-05 module is an easy to use Bluetooth SPP (Serial Port
Protocol) module, designed for transparent wireless serial
connection setup. Serial port Bluetooth module is fully
qualified Bluetooth V2.0+EDR (Enhanced Data Rate)
3Mbps Modulation with complete 2.4GHz radio transceiver
and baseband. It uses CSR Blue core 04-External single
chip.
Fig. 3.2.3: Bluetooth Module

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3.2.4: Power Supply:
Fig. 3.2.4: Setup of power supply used

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3.3: Software Description:
3.3.1: Android Operating System:
Android is an open-source operating system which means
that any manufacturer can use it in their phones free of
charge. It was built to be truly open. Android is built on the
open Linux Kernel. Furthermore, it utilizes a custom JAVA
virtual machine that was designed to optimize memory and
hardware resources in a mobile environment.
Fig 3.3.1: Android Operating System
An android app is meant for phones with an android based
operating systems. They can be downloaded from the
android app Market which is pre-loaded on every android
phone. Blue control APP and Bluetooth Spp APP are some
examples.

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3.3.2:Arduino Integrated
Development Environment:
The open-source Arduino Software (IDE) makes it easy to
write code and upload it to the board. It runs on Windows,
Mac OS X, and Linux. The environment is written in Java
and based on Processing and other open-source software.
This software can be used with any Arduino board.It
contains a text editor for writing code, a message area, a
text console, a toolbar with buttons for common functions
and a series of menus. It connects to the Arduino and
Genuino hardware to upload programs and communicate
with them. Programs written using Arduino Software (IDE)
are called sketches. These sketches are written in the text
editor and are saved with the file extension .ino.
There are two special functions that are a part of
every Arduino sketch: setup() and loop() . The setup() is
called once, when the sketch starts. It's a good place to do
setup tasks like setting pin modes or initializing libraries.
The loop() function is called over and over and is heart of
most sketches.

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Fig. 3.3.2: Android Integrated Development Environment
We started this project in previous semester. Since then,
we have come a long way in completing the entire project.
Let us review the work done by us in previous semester.
To keep the project cost effective, we have implemented
Arduino Uno on breadboard.

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3.4: Implementation of Arduino Uno
on breadboard:
Fig. 3.4.1: Arduino Uno on breadboard
The steps mentioned below are to be followed to create the
set up shown above.
Step 1: Adding power and ground wires for where our
voltage regulator willbe.
Fig. 3.4.2: Add power and ground wire to voltage regulator

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Step 2:Adding power and ground wires at the bottom of our
board connecting each rail.
Fig. 3.4.3: Add power and ground wire to bottom of our board connecting each
rail.
Step 3:Adding the 7805 power regulator and the lines to
power the board. The regulator is a TO-220 package where
the Input from the external power supply goes input on the
left, ground is in the middle and the 5V output is on the
right (when facing the front of the regulator). Add power
OUT and ground wires that connect to the right and left
rails of the breadboard. Also a 10uF capacitor between the
IN of the regulator and the ground as well as a 10uF
capacitor on the right rail between power and ground. The
silver strip on the capacitor signifies the ground leg.
Fig. 3.4.4: Add 7805 power regulator and two 10uF capacitor

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Step 4:Adding an LED and a 220-ohm resistor on the left
side of your board across from the voltage regulator. An
LED attached to power like this is a great trouble shooting
trick. We'll always know when our board is being powered
as well as quickly know if your board is being shorted.
Fig. 3.4.5: Add LED and 220 ohm resistor
The red and black wires to the left of the voltage regulator
are where our power supply will be plugged in. The red wire
is for the power and the black wire is for the ground. We
only attach a power supply that is between 7-16V. Any
lower and you won't get 5V out of our regulator. Any higher
and our regulator may be damaged. A 9V battery, 9V DC
power supply, or 12V DC power supply is suitable.

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Step 5: Connecting a 10k ohm pull up resistor to +5V from
the reset pin in order to prevent the chip from resetting
itself during normal operation. The reset pin reboots the
chip when pulled down to ground. In later steps we will
show you how to add a reset switch that takes advantage of
this.
Fig. 3.4.6: Add 10k ohm resistor and Atmega 328p
The pins are connected as follows:
1. Pin 7 - Vcc - Digital Supply Voltage
2. Pin 8 - GND
3. Pin 22 - GND
4. Pin 21 - AREF - Analog reference pin for ADC
5. Pin 20 - AVcc - Supply voltage for the ADC converter.

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Step 6: Adding a 16 MHz external clock between pin 9 and
10, and add two 22 pF capacitors running to ground from
each of those pins.
Fig 3.4.7: Add 16 MHz clock and two 22 pF capacitors
Step 7: Adding the small tactile switch so that we can reset
the Arduino whenever we'd like and prepare the chip for
uploading a new program. A quick momentary press of this
switch will reset the chip when needed. Add the switch just
above the top of the Atmega chip crossing the gap in the
breadboard. Then, add a wire from the bottom left leg of the
switch to the RESET pin of the Atmega chip and a wire
from the top left leg of the switch to ground.
Fig. 3.4.8: Add tactical switch

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Step 8:Finally, adding the LED. The long leg or the anode
connects to the red wire and the short leg or the cathode
connects to the 220 ohm resistor going to ground.
Following all above steps we have made our own Arduino
UNO board shown below.
Fig. 3.4.9: Final implementation of Arduino Uno on breadboard

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3.5: Checking our Arduino Circuit:
Now to see whether our Arduino is working or not, we
upload a blinking LED program in it.It turns the LED on
and off after a delay of 250 ms. The code and flowchart of
the same is given below.
3.5.1: FLOWCHART
Fig. 3.5.1: Flowchart to check arduino circuit

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3.5.2: CODE:
intledPin = 10;
void setup() {
pinMode(ledPin, OUTPUT);
}
void loop() {
digitalWrite(ledPin, HIGH);
delay(250);
digitalWrite(ledPin, LOW);
delay(250);
}

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The response of the above program is shown below:
When green LED is on:
Fig. 3.5.2.1: Response of program when LED is on
When green LED is off:
Fig. 3.5.2.2: Response of program when LED is off

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CHAPTER- 4
PROJECT WORK

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CHAPTER- 4
4.1: INTRODUCTION
Although home automation today is not a new thing but
most advanced home automation systems in existence
today require a big and expensive change of infrastructure.
This means that it often is not feasible to install a home
automation system in an existing building.
“Homatic” is a wireless home automation application that
is supposed to be implemented in existing home
environments, without any changes in the existing
infrastructure.
“Homatic” lets the user to control his home from his or her
android smart phone. In the smart phone application the
user can select actions what should happen with electrical
and/or electronic devices in the network.
Mobile phone is a revolutionary invention of the century. It
was primarily designed for making and receiving calls &
text messages, but it has become the whole world after the
Smart phone comes into the picture. In this project we are
building a home automation system, where one can control
the home appliances, using the Bluetooth based
Smartphone, just by sending commands via Bluetooth from
an application designed for this project.

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4.2: BLOCK DIAGRAM
Fig. 4.2: Block diagram of the project
This application controls the various appliances connected
to your arduino and relays. When the toggle buttons on the
application are pressed, corresponding bluetooth signals
are sent from your android phone to he Bluetooth module
you have hooked up to your arduino. The arduino finds out
which signal was sent and compares it to the predefined
signals assigned for each appliance. When it identifies that
signal, then the arduino activates the relay hooked up to
its digital pin by passing 5V through it. Thus the relay is
switched ON and the corresponding appliance connected to
the relay is turned ON as well. To switch it OFF, arduino
passes a 0V or logic low to its digital pin.

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4.3: CIRCUIT DIAGRAM
Fig. 4.3.1: Circuit diagram of the project
This project consists of a microcontroller, two 6V relays, a
bulb, a fan and Bluetooth module. Here ATMEGA328p
microcontroller is used. It is an 8 bit microcontroller and it
requires supply voltage of 5V DC. Use 7805 power supply
circuit to provide 5V DC to the microcontroller. We can use
9V DC battery or 12V, 1A adapter to provide the supply to
the circuit. For the above circuit additionally you need to
connect reset circuit and crystal circuit to the controller to
work properly.
Bluetooth module TX and RX pins are connected to the
RXD and TXD pins of controller. Vcc pin is connected to
the 5V and GND pin is connected to ground.

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Controller communicates with Bluetooth module using
serial communication (UART protocol). Use a baud rate of
9600 to communicate with Bluetooth. To change the
Bluetooth name and password then you need to use
Bluetooth AT commands.
Below are the few Bluetooth AT commands:
AT — Responds OK. (Used to test the Bluetooth module)
AT+RESET — Responds OK. (Used to reset the module)
AT+NAME? — Responds with the module name.
AT+NAME = <name> — Responds OK. Name should be less
than or equal to 20 characters.
AT+PSWD? — Responds with the existing password.
AT+PSWD =<password> — Sets module pairing password.
Electrical loads (bulb and fan) are connected through the
relays. Here relays are used to switch AC loads using small
DC voltages. NPN transistors are used to drive the relays.
Remote Password Operated Home Appliances Control
Project Algorithm:
 Initialize UART protocol.
 Now read the data from Bluetooth module.
 Compare the received string with predefined strings
and accordingly switch the electrical loads.

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Now the steps for implementing the home automation
circuit are as follows:
The connection diagram for arduino is as shown. For
setting up this system, wiring connections have to be made
between the arduino and bluetooth module and also with
the relays.
Step I: Connecting Bluetooth
The bluetooth module’s Tx is connected to arduino Rx
(digital pin 0) and the module’s Rx to arduinoTx (digital
pin 1). 5V and GND of the module is connected to the
arduino’s 5V and GND.
Step II: Connecting Relay Driver
The relay driver chip consist of total 16 pins (8 pins both
side) where pin 1 to 7 are input from digital pins of
Arduino and pin 10 to 16 are for the output to the relay
switches. The pin 8 is connected to ground and pin 9 to
+12v supply. Here in our project, we are connecting digital
pin 7 and 8 (pin 13 and 14 of Atmel328) to the pin 1 and
2 of relay driver.
Step III: Connecting Relay Switches
The relay we’re using is SPDT, it has 5 pins on the
underside. As shown below, here pins 1 and 3 are the coil
pins. Pin 1 is connected to the pin 16 and 3 is connected
to arduino GND. Pin 2 is the common contact in the relay
to which you have to connect the power for our appliance
(AC 230V), and 4 is the pin to which you have to connect
our appliance wire.
Fig. 4.3.2: Relay pins

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Step IV:Connecting your appliance to the
relay
In a normal SPDT relay, whose pin out is shown in the
above step, pins 2 and 4 act identical to the two terminals
of a switch. When digital HIGH voltage is applied from the
arduino to the relay, switch turns ON, when the voltage is
withdrawn it turns OFF. We can attach this system you
made to a normal switchboard by extending the wires from
behind the switches in the board to your relay.
As seen in the connection diagram in the above step, you
have to connect a power AC line to the common terminal of
all the relays. Then, you have to extend the wires from
behind the switchboard of the corresponding lights/lamps
you wish to control. Each of these wires are connected to
the “NO”(Normally Open) terminal of the relays (pin no 4 in
step no 1’s relay pin out diagram).
Step v: Loading the arduino software
Here it checks the incoming bluetooth signal via the
bluetooth module and then compares (ASCII values) using
an “if” statement with previously defined values. If it
matches the value, relay is activated using
“digitalWrite(pin,HIGH)” command , which passes 5V to the
arduino digital pin.

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Step VI: Downloading the android
application and setting up Bluetooth
There are a lot of applications available in Google playstore
for home automation. We install any one of them.Once you
have installed the application, before opening it you need to
pair and connect with your bluetooth module. For this, you
need to power the arduino and bluetooth module and then
turn ON the bluetooth of your phone and make it visible to
other devices. After that, search for new devices in
bluetooth, select your bluetooth module from the list, enter
the pairing code when prompted ,it is usually ’1234′ or
’0000′ .Note the name of your device , in this case it is “HC-
05″.
After pairing with the system, go to the application and
enter the name of your bluetooth module you noted earlier
(case-sensitive) and click “OK”. After that the phone will get
connected to your system, and on clicking the respective
buttons, the appliances turn ON/OFF.

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4.4:FLOWCHART
Fig. 4.4: Flowchart of the program

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4.5: PROGRAM CODE
String voice;
int led1 = 2; //Connect LED 1 To Pin #2
int led2 = 3; //Connect LED 2 To Pin #3
//--------------------------Call A Function-------------------------
------//
voidallon(){
digitalWrite(led1, HIGH);
digitalWrite(led2, HIGH);
}
voidalloff(){
digitalWrite(led1, LOW);
digitalWrite(led2, LOW);
}
//----------------------------------------------------------------------
-//
void setup() {
Serial.begin(9600);
pinMode(led1, OUTPUT);
pinMode(led2, OUTPUT);
}
//----------------------------------------------------------------------
-//

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void loop() {
while (Serial.available()){ //Check if there is an available
byte to read
delay(10); //Delay added to make thing stable
char c = Serial.read(); //Conduct a serial read
if (c == '#') {break;} //Exit the loop when the # is detected
after the word
voice += c; //Shorthand for voice = voice + c
}
if (voice.length() > 0) {
Serial.println(voice);
//----------------------------------------------------------------------
-//
//----------Control Multiple Pins/ LEDs----------//
if(voice == "*all on") {allon();} //Turn Off All Pins (Call
Function)
else if(voice == "*all off"){alloff();} //Turn On All Pins (Call
Function)
//----------Turn On One-By-One----------//
else if(voice == "*light on") {digitalWrite(led1, HIGH);}
else if(voice == "*fan on") {digitalWrite(led2, HIGH);}
//----------Turn Off One-By-One----------//
else if(voice == "*light off") {digitalWrite(led1, LOW);}

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else if(voice == "*fan off") {digitalWrite(led2, LOW);}
//----------------------------------------------------------------------
-//
voice="";}} //Reset the variable after initiating

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CHAPTER- 5
RESULT AND ANALYSIS

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CHAPTER- 5
5.1: Truth Table
INPUT:1 OUTPUT:1 INPUT:2 OUTPUT:2
Manual
switch:
1
Relay
switch:
2
Light Manual
switch:
1
Relay
switch:
2
Fan
0 0 0 0 0 0
0 1 1 0 1 1
1 0 1 1 0 1
1 1 0 1 1 0
Table 5.1: Truth table of the project

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5.2: Snapshot and Screenshots of
the project
Fig 5.2.1: when both (Light and Fan) are off
Fig 5.2.2: when Light is on

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Fig 5.2.3: When Fan is on
Fig 5.2.4: When both (Light and Fan) are on

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5.3: MERITS
1. It is a robust and easy to use system.
2. There is no need for extra training of that person who
is using it.
3. All the control would be in your hands by using this
home automation system.
4. This project can provide the facility of monitoring all
the appliances within the communication range through
Bluetooth.
5. The schematic of Arduino is open source, for the
future enhancement of the project board can be extended
to add more hardware features.
6. The inefficiency of operation of conventional wall
switches can be overwhelmed using various home
automation systems (without using conventional switching
methods).
7. The loss of power can be reduced and manpower
required for home automation is very less compared to
conventional methods.
8. Provides safety from electrical power short circuits
while using conventional wall switches to operate loads.

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5.4:DEMERITS
1. Bluetooth is used in this home automation system,
which have a range of 10 to 20 meters so the control
cannot be achieved from outside this range.
2. Application is disconnected after disconnect of the
Bluetooth.
3. When the new users want to connect, first download
application software and then configuration must be done.
4. Security problem
5.5: FUTURE SCOPE:
This project can be further developed by integrating it with
the internet to monitor your home while sitting in a remote
area. By doing this, one can keep an eye on his or her
home through an internet connected to the user’s mobile
phone or PC or laptop. This will not only improve the
security of your home in this modern day world but will
also assist in conservation of energy like if you left any
home appliance switched on by mistake, then you can
check the status of the appliance on the graphical interface
made on your mobile and can switch it off using the net
connectivity.

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CHAPTER-6
REFERENCE

53. 53
CHAPTER-6
REFERENCE
[1] www.electronicshub.org
[2] www.engineersgarage.com
[3] www.atmel.com
[4] www.arduino.org
[5] Home Automation For Dummies by Dwight Spivey
[6] How to Get Started with Home Automation by Author
Mymitram
[7] Getting Started with Arduino by Massimo Banzi