i

MICROCONTROLLER BASED ULTRASONIC

STICK FOR VISUALLY IMPAIRED

AN INTERNSHIP REPORT

Submitted by

CALEB RUBIN S P (2016105022)

PRASANTH V (2016105059)

THEYANESHWARAN J (2016105075)

DIVAKAR M (2016105525)

in summer internship project

of

BACHELOR OF ENGINEERING

in

ELECTRONICS AND COMMUNICATION ENGINEERING

COLLEGE OF ENGINEERING GUINDY

ANNA UNIVERSITY :: CHENNAI 600 025

MAY 2018

ii

COLLEGE OF ENGINEERING GUINDY

ANNA UNIVERSITY :: CHENNAI 600 025

MAY 2018

INTERNSHIP CERTIFICATE

Certified that this internship report “MICROCONTROLLER BASED

ULTRASONIC STICK FOR VISUALLY IMPAIRED” is the work of

CALEB RUBIN S P (2016105022), PRASANTH V (2016105059),

THEYANESHWARAN J (2016105075) and DIVAKAR M (2016105525) who

carried out the internship project work under my supervision from 8th May, 2018

to 31st May, 2018.

DR. S. MUTTAN

HEAD OF THE DEPARTMENT

Professor

ECE Department

College of Engineering Guindy

Anna University, Chennai – 25.

DR. D. SRIDHARAN

CO-ORDINATOR

Professor

ECE Department

College of Engineering Guindy

Anna University Chennai - 25

DR. N.RAMADOSS

SUPERVISOR

Associate Professor

ECE Department

College of Engineering Guindy

Anna University Chennai - 25

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ACKNOWLEDGEMENT

The final outcome of this project required a lot of guidance and assistance from

many people and we are extremely privileged to have got this all along the

completion of this project. All that we have done is only due to such supervision

and assistance and we would not forget to thank them.

We respect and thank our Dean Dr. T.V.Geetha for providing us with this Summer

Internship opportunity as it was a great learning experience for all of us.

We respect and thank the Department of Electronics and Communication

Engineering and Dr.Muttan the HOD, Department of ECE, for providing us the

infrastructure for the completion of our internship project.

We thank Dr.D.Sridharan for co-ordinating us throughout the internship program

and for guiding us to optimize our project more efficiently.

We owe our deep gratitude to our project guide and coordinator Dr.N.Ramadass,

who took keen interest on our project work and guided us all along, till the

completion of our project work by providing all the necessary information for

developing a good system and without the Grace of God we would not have

completed this project successfully.

Caleb Rubin S P

Prasanth V

Theyaneshwaran J

Divakar M.

1

ABSTRACT

Visually impaired persons find themselves challenging to go out

independently. There are millions of visually impaired or blind people in this world

who are always in need of helping hands. In this technology controlled world,

where people strive to live independently, this project proposes an ultrasonic stick

for visually impaired people to help them gain personal independence. Since this is

economical and not bulky, one can make use of it easily. This project helps

visually challenged people to navigate with ease using advance technology. The

blind stick is integrated with ultrasonic sensors, Location Tracker using

NodeMCU, application software that would give the blind people’s location, RF

Transmitter, RF Receiver along with light and water sensing which are controlled

by microcontroller. The implementation is done and the entire setup functions

using the microcontroller.

2

TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT 1

TABLE OF CONTENTS 2

LIST OF FIGURES 5

1. OVERVIEW

1.1 Introduction 6

1.2 Objective of This Project 6

1.3 Literature Survey 7

2. ULTRASONIC SENSOR

2.1 Introduction 8

2.2 Ultrasonic Sensor Pin Configuration 9

2.3 Ultrasonic Sensor Pin Features 10

2.4 HC-SR04 Working Principle 10

2.5 HC-SR04 Procedure 11

2.6 Distance Calculation 11

3. MOISTURE SENSOR

3.1 Introduction 12

3.2 Moisture Sensor Pin Configuration 13

3.3 Moisture Sensor Pin Features 13

3.4 Hardware and Software Required 13

3

3.5 Moisture Sensor Working 14

3.6 Moisture Sensor Circuit Connection 15

4. STICK FINDER USING RF COMMUNICATION

4.1 Introduction 16

4.1.1 RF Module 17

4.1.2 RF Module Specifications 17

4.2 RF Transmitter 18

4.2.1 RF Transmitter Pin Description 18

4.2.2 RF Transmitter Features 18

4.3 RF Receiver 19

4.3.1 RF Receiver Pin Description 19

4.3.2 RF Receiver Features 19

4.4 Circuit Configuration 20

5. ANDROID STUDIO

5.1 Introduction 21

5.2 Creating App using Android Studio. 21

6 ARDUINO

6.1 Introduction 25

6.2 Arduino Nano 26

6.3 Arduino Nano Specifications 26

6.4 Arduino Nano Interfacing 27

7 NODEMCU

7.1 Introduction 28

7.2 NodeMCU Specifications 29

4

8 WEB HOSTING

8.1 Introduction 30

8.2 Website Viewing 30

8.3 000 Webhost 31

8.4 Steps required to create a Domain 31

8.5 Accessing Database through Public Url 32

8.6 Accessing Location through Android Studio 33

9 LOCATION TRACKING USING NODEMCU

9.1 Introduction 34

9.2 Working of Google Geolocation 34

9.3 Getting API key 35

10 RESULT & CONCLUSION

10.1 Result 36

10.2 Conclusion 37

REFERENCES 37

5

LIST OF FIGURES

Figure 2.1 Ultrasonic Working Principle

Figure 2.2 Ultrasonic Sensor HC-SR04

Figure 2.3 HC-SR04 Timing Diagram

Figure 3.1 Moisture Sensor

Figure 3.2 Moisture Sensor Connection with Arduino

Figure 4.1 RF Communication Block Diagram

Figure 4.2 RF Transmitter Pin Configuration

Figure 4.3 RF Receiver Pin Configuration

Figure 4.4 RF Transmitter Configuration

Figure 4.5 RF Receiver Configuration

Figure 5.1 “CLICKME” Button to activity main

Figure 5.2 App Created using Android Studio

Figure 6.1 Arduino Nano Pin out

Figure 6.2 Arduino Code for getting location

Figure 7.1 NodeMCU

Figure 7.2 NodeMCU Pin Configuration

Figure 8.1 Public URL Displaying Location

Figure 8.2 CLICKME Button pressed

Figure 9.1 Displaying API key

Figure 10.1 Final Completed Setup

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CHAPTER 1

OVERVIEW

1.1 INTRODUCTION

According to the World Health Organization (WHO) statistics, around

30 billion people are blind on the earth. This project proposes to design and

develop a portable unit (stick) for them for easy usage and navigation in public

places.

Our proposed project first uses NodeMCU to track blind people’s

location using Google’s Geolocation API and this data is communicated with

others by using a application software in smartphone created by using Android

Studio. Whenever blind people met with a obstacle it would alert them by

using vibration using ultrasonic sensors. The stick is interfaced with other

features like LDR, Moisture sensor. The system has one more advanced feature

integrated to help the blind find their stick if they forget where they kept it. A

wireless RF based remote is used for this purpose. In order to control all these

sensors we use the popular Arduino as microcontroller.

1.2 OBJECTIVE OF THIS PROJECT

The objective of this project is to develop a stick interfacing with

ultrasonic sensors, NodeMCU, Moisture sensor, RF Transmitter and

Receiver and LDR controlled using microcontroller and to create an

application software using Android Studio which tracks our location.

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1.3 LITERATURE SURVEY

1. S.Gangwar (2011) designed a smart stick for blind which can give early

warning of an obstacle using Infrared (IR) sensors. After identifying the

obstacles, the stick alerts the visually impaired people using vibration

signals. However the smart stick focused only for obstacle detection

but it is not assisting for emergency purposes needed by the blind.

And also the IR sensors are not really efficient enough because it can

detect only the nearest obstacle in short distance.

2. S.Chew (2012) proposed the smart white cane, called Blind spot that

combines GPS technology, social networking and ultrasonic sensors to

help visually impaired people to navigate public spaces. The GPS detects

the location of the obstacle and alerts the blind to avoid them hitting the

obstacle using ultra-sonic sensors. But GPS did not show the efficiency

in tracing the location of the obstacles since ultra-sonic tells the

distance of the obstacle.

All the studies show that, there are many techniques of making a smart stick for

blind people. However, the study conclusion shows that, using the ultrasonic

sensors would be an efficient solution to detect the obstacles with maximum

range of 7 meters and 45 degree coverage.

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CHAPTER 2

ULTRASONIC SENSOR

2.1 Introduction

The ultrasonic sensor works on the principle of SONAR and

RADAR system which is used to determine the distance to an object.An

ultrasonic sensor generates the high-frequency sound (ultrasound) waves.

When this ultrasound hits the object, it reflects as echo which is sensed by

the receiver. By measuring the time required for the echo to reach to the

receiver, we can calculate the distance.

Fig 2.1 Ultrasonic Working Principle.

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2.2 Ultrasonic Sensor Pin Configuration:

`

Fig 2.2 Ultrasonic Sensor HC-SR04

Pin

Number Pin Name Description

1 Vcc The Vcc pin powers the sensor, typically

with +5V

2 Trigger

Trigger pin is an Input pin. This pin has to

be kept high for 10us to initialize

measurement by sending US wave.

3 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.

4 Ground This pin is connected to the Ground of the

system

Table 2.1 Pin Description of Ultrasonic Sensor HC-SR04.

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2.3 Ultrasonic Sensor Pin Features:

1. Operating voltage : +5V

2. Theoretical Measuring Distance : 2cm to 450cm

3. Practical Measuring Distance : 2cm to 80cm

4. Accuracy : 3mm

5. Measuring angle covered : <15°

6. Operating Current : <15mA

7. Operating Frequency : 40Hz

2.4 HC-SR04 Working Principle:

HC-SR-04 has an ultrasonic transmitter, receiver and control circuit. In

ultrasonic module HCSR04, we have to give trigger pulse, so that it will generate

ultrasound of frequency 40 kHz. After generating ultrasound i.e. 8 pulses of 40

kHz, it makes echo pin high. Echo pin remains high until it does not get the echo

sound back. So the width of echo pin will be the time for sound to travel to the

object and return back. Once we get the time we can calculate distance, as we

know the speed of sound.

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2.5 HC-SR04 Procedure:

We need to transmit trigger pulse of at least 10 us to the HC-SR04 Trig Pin.

Then the HC-SR04 automatically sends Eight 40 kHz sound wave and wait for

rising edge output at Echo pin. When the rising edge capture occurs at Echo pin,

start the Timer and wait for falling edge on Echo pin. As soon as the falling edge is

captured at the Echo pin, read the count of the Timer. This time count is the time

required by the sensor to detect an object and return back from an object.

Fig 2.3 HC-SR04 Timing Diagram

2.6 Distance Calculation:

Distance = Speed x Time.

The speed of sound waves is 343 m/s.

So, Total Distance = (343 x Time of High(Echo) Pulse)/2

Total distance is divided by 2 because signal travels from HC-SR04 to

object and returns to the module HC-SR-04.

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CHAPTER 3

MOISTURE SENSOR

3.1 Introduction:

The Moisture sensor is used to measure the water content of soil. A

typical Soil Moisture Sensor consists of two components. A two legged Lead,

that goes into the soil or anywhere else where water content has to be measured.

This has two header pins which connect to an Amplifier/ A-D circuit which is

in turn connected to the Arduino. The Amplifier has a Vin, Gnd, Analog and

Digital Data Pins. This means that you can get the values in both Analog and

Digital forms.

Fig 3.1 Moisture Sensor

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3.2 Moisture Sensor Pin Configuration :

The soil Moisture sensor FC-28 has four pins

1. VCC : For power

2. A0 : Analog output

3. D0 : Digital output

4. GND : Ground

3.3 Moisture Sensor Pin Features:

The specifications of the soil moisture sensor FC-28 are as follows:

1. Input Voltage : 3.3-5V

2. Output Voltage : 0-4.2V

3. Input Current : 35mA

4. Output Signal : Both Analog and Digital.

3.4 Hardware and Software Required:

Moisture Sensor Module.

Arduino Uno.

Arduino IDE(1.0.6 Version).

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3.5 Moisture Sensor Working:

The soil moisture sensor consists of two probes which are used to

measure the volumetric content of water. The two probes allow the current to

pass through the soil and then it gets the resistance value to measure the

moisture value. When there is more water, the soil will conduct more electricity

which means that there will be less resistance. Therefore, the moisture level will

be higher. Dry soil conducts electricity poorly, so when there will be less water,

then the soil will conduct less electricity which means that there will be more

resistance. Therefore, the moisture level will be lower. This sensor can be

connected in two modes; Analog mode and digital mode. The Module contains

a potentiometer which will set the threshold value and then this threshold value

will be compared by the LM393 comparator. The output LED will light up and

down according to this threshold value.

To connect the soil moisture sensor FC-28 in the digital mode,

Connect the digital output of the sensor to the digital pin of the Arduino.

When the sensor value will be greater than the threshold value, then the

digital pin will give us 5V and the LED on the sensor will light up and when

the sensor.

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3.6 Moisture Sensor Circuit Connection:

The connections for connecting the soil moisture sensor FC-28 to the Arduino in

digital mode are as follows:

1. VCC of FC-28 - 5V of Arduino

2. GND of FC-28 - GND of Arduino

3. D0 of FC-28 - pin 12 of Arduino

4. Vibrator positive - pin 13 of Arduino

5. Vibrator negative - GND of Arduino

Fig 3.2 Moisture Sensor with Arduino

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CHAPTER 4

STICK FINDER USING RF COMMUNICATION

4.1 Introduction Wireless communication is among technology’s biggest

contributions to mankind. Wireless communication involves the transmission of

information over a distance without help of wires, cables or any other forms of

electrical conductors. The transmitted distance can be anywhere between a few

meters (for example, a television’s remote control) and thousands of kilometres

(for example, radio communication). In this technology, the information can be

transmitted through the air without requiring any cable or wires or other electronic

conductors, by using electromagnetic waves like IR, RF, satellite, etc.

Fig 4.1 RF Communication Block Diagram

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4.1.1 RF Module

The 433MHz wireless module is one of the cheap and easy to use

modules for all wireless projects. These modules can be used only in pairs and only

simplex communication is possible. Meaning the transmitter can only transmit

information and the receiver can only receive it. The module could cover a

minimum of 3 meters and with proper antenna a power supplies it can reach upto

100 meters.

The module itself cannot work on its own as it required some kind of

encoding before being transmitter and decoding after being received; so it has to be

used with an encoder or decoder IC or with any microcontroller on both ends. The

simplest way to use it is with the HT12E Encoder IC and HT12D Decoder IC. The

module uses ASK (Amplitude shift keying) and hence it’s easy to interface with

microcontrollers as well.

4.1.2 RF Module Specifications

1. Wireless (RF) Simplex Transmitter and Receiver

2. Transmitter Operating Voltage : +5V only

3. Transmitter Operating current : 9mA to 40mA

4. Operating frequency : 433 MHz

5. Modulating Technique : ASK (Amplitude shift keying)

6. Data Transmission speed : 10Kbps

7. Circuit type : Saw resonator

8. Low cost and small package.

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4.2 RF Transmitter

Fig 4.2 RF Transmitter Pin Configuration

4.2.1 RF Transmitter Pin Description

1. Data : Data to be transmitted is sent to this pin

2. Vcc : Power supply

3. Ground : Connected to the ground of the circuit

4. Antenna : Solder wire/antenna to improve range

4.2.2 RF Transmitter Features

The Vcc pin has a wide range input voltage from 3V to 12V. The

transmitter consumes a minimum current of 9mA and can go as high as 40mA

during transmission. The center pin is the data pin to with the signal to be

transmitted is sent. This signal is then modulated using the ASK (Amplitude Shift

Keying) and then sent on air at a frequency of 433MHz. The speed at which it can

transmit data is around 10Kbps.

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4.3 RF Receiver

Fig 4.3 RF Receiver Pin Configuration

4.3.1 RF Receiver Pin Description

1. Vcc : Power supply (3V to 12V)

2. Data : Data received can be obtained from this pin

3. Data : It serves the same purpose (any one can be used)

4. Ground : Connected to the ground of the circuit

5. Antenna : Solder wire/antenna to improve range

4.3.2 RF Receiver Features

The Vcc pin should be powered with a regulated 5V supply. The

operating current of this module is less than 5.5mA. The pins Dout and Linear out

is shorted together to receive the 433Mhz signal from air. This signal is then

demodulated to get the data and is sent out through the data pin.

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4.4 Circuit Configuration

The circuit is divided into transmitter and receiver sections. The

transmitter section consists of an RF Transmitter, HT12E encoder IC and push

button. A 680 KΩ resistor is connected between the oscillator terminals of encoder

IC. This is to enable the oscillator

Fig 4.4 RF Transmitter Configuration

The receiver section consists of RF Receiver, HT12D Decoder IC and

LED. An extra LED is connected to VT (Valid Transmission) pin of the decoder

IC. This is used to indicate a successful transmission of data. A 33 KΩ resistor is

connected between the oscillator pins of decoder IC.

Fig 4.5 RF Receiver Configuration

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CHAPTER 5

ANDROID STUDIO

5.1 Introduction

Android Studio is an integrated development environment (IDE)

from Google that provides developers with tools needed to build applications

for the Android OS platform.

Android Software Development Kit (SDK) is a toolset that enables

developers to create apps for Android OS. It includes the required libraries to

build Android apps, a debugger, an emulator, Application Programming

Interfaces (APIs) and sample projects with source code, so you can have

everything you need to start making your own apps.

The Android Virtual Device Manager provides a graphical user

interface to test your app on a virtual device.

5.2 Creating App using Android Studio

Step 1: Install Android Studio

1. Go to http://developer.android.com/sdk/index.html to download Android

Studio.

2. Use the installer to install Android Studio.

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Step 2: Open a New Project

1. Open Android Studio.

2. Under the "Quick Start" menu, select "Start a new Android Studio

project."

3. On the "Create New Project" window that opens, name your project .

4. Click "Next."

5. Make sure on that "Phone and Tablet" is the only box that is checked.

6. If you are planning to test the app on your phone, make sure the

minimum SDK is below your phone's operating system level.

7. Click "Next."

8. Select "Blank Activity."

9. Click "Next."

10. Leave all of the Activity name fields as they are.

11. Click "Finish."

Step 3: Add a Button to the Main Activity

1. Navigate to the Design tab of the activity_main.xml display.

2. In the Palette menu to the left of the phone display, find Button (under

the heading Widgets).

3. Click and drag Button to be centered underneath your welcome message.

4. Make sure your button is still selected.

5. In the Properties menu (on the right side of the window), scroll down to

find the field for "text."

6. Change the text from "New Button" to "Clickme."

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Step 4: Access Location from Database

1. Get the location from database when the database receives latitude and

longitude.

Fig 5.1 “CLICKME” Button to activity_main.

Step 5: Write the Button’s “onClick” method

1. Once the location received press the “CLICKME” button to

navigate the person to the blind one.

Fig 5.2 App Created using Android Studio.

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Step 6: Build and run app.

1. In Android Studio, click the Run menu option (or the play button

icon) to run app.

2. When prompted to choose a device, choose one of the following

options:

3. Select the Android device that is connected to computer via USB.

4. Alternatively, select the LAUNCH EMULATOR button and

choose virtual device that is previously configured.

5. Click ok.

Android Studio will invoke Gradle to build app, and the display the

results on the device or on the emulator. It could take a couple of

minutes before the app opens.

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CHAPTER 6

ARDUINO

6.1 Introduction

Arduino is an open-source platform used for building electronics

projects. Arduino consists of both a physical programmable circuit board (often

referred to as a microcontroller) and a piece of software, or IDE (Integrated

Development Environment) that runs on your computer, used to write and

upload computer code to the physical board.

The Arduino platform has become quite popular with people just

starting out with electronics, and for good reason. Additionally, the Arduino

IDE uses a simplified version of C++, making it easier to learn to program.

What you will need:

1. A computer (Windows, Mac, or Linux)

2. An Arduino-compatible microcontroller

3. A USB A-to-B cable, or another appropriate way to connect your

Arduino-compatible microcontroller to your computer.

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6.2 Arduino Nano

Fig 6.1 Arduino Nano Pinout

The Arduino Nano, as the name suggests is a compact, complete and

bread-board friendly microcontroller board.

6.2 Arduino Nano Specifications:

Microcontroller : ATmega328P

Architecture : AVR

Operating Voltage : 5 Volts

Flash Memory : 32 KB of which 2 KB used by BootLoader

Clock Speed : 16 MHz

Analog I/O Pins : 8

EEPROM : 1 KB

Input Voltage : 7-12 Volts.

27

6.4 Arduino Nano Interfacing

Step 1: Install Arduino Software

1. Go to https://www.arduino.cc/en/Main/Software to download Arduino

Software.

2. Use the installer to install Arduino Software.

Step 2: Install Drivers for Arduino.

Step 3: Upload Code in Arduino.

Fig 6.2 Arduino Code for getting location.

1. Once arduino IDE is installed on the computer, connect the board with

computer using USB cable.

2. Now open the arduino IDE and choose the correct board by selecting

Tools>Boards>Arduino/Nano,

3. Choose the correct Port by selecting Tools>Port.

4. Once the code is loaded into your IDE, click on the ‘upload’ button given on

the top bar.

28

CHAPTER 7

NODEMCU

7.1 Introduction

NodeMCU is an open source IoT platform. It includes firmware which

runs on the ESP8266 Wi-Fi SoC from Espressif Systems, and hardware which is based

on the ESP-12 module. The term "NodeMCU" by default refers to the firmware rather

than the development kits.

It is an Open source, Interactive, Programmable, Low cost , WiFi enabled ,

USB-TTL included System on Chip.

Fig 7.1 NodeMCU

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7.2 NodeMCU Specifications

1. Wi-Fi Module – ESP-12E module similar to ESP-12 module but with 6

extra GPIOs.

2. USB – micro USB port for power, programming and debugging

3. Headers – 2x 2.54mm 15-pin header with access to GPIOs, SPI, UART,

ADC, and power pins

4. Power – 5V via micro USB port

5. Dimensions – 49 x 24.5 x 13mm

6. Memory: 128kb

7. Storage: 4Mb

8. Type: Single Board Microcontroller

Fig 7.2 NodeMCU Pin Configuration

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CHAPTER 8

WEB HOSTING

8.1 Introduction

Web hosting is a service that enables individuals and companies to

make their website available and accessible to the whole world via World Wide

Web. It is a kind of internet hosting service whereby a web hosting company grants

its users space on ‘servers’ and provides internet connectivity. Thus, through the

use of webhost services, web pages consisting of contents, data, images etc. can be

viewed on the internet through varied technologies and services.

8.2 Website viewing

The only thing required to make your website accessible to internet

users is to have a domain for your website. The moment any internet user types

your domain or website address, the computer would automatically detect it and

would connect to your server. Consequently, the web pages would be delivered to

them through the browser.

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8.3 000 Webhost

000Webhost is a website hosting service provider that helps

to host your own website and create a domain. 000Webhost, provides you

with Free Website hosting. It is one of the oldest; free web hosting providers in the

industry. Featured with distinctive features, this web host provides its users with an

opportunity to initiate something amazing via accessing web pages online. It’s

great for the start-up holders. It still continues to be a good source for bringing

ideas into reality.

8.4 Steps required to create a Domain.

1. Enter www.000webhost.com

2. Sign in with account.

3. Enter website name as blindstick.com

4. Click Manage database and click New database.

5. Enter database name, Username, Password

6. Click phpMyAdmin.

7. Enter table name = geolocationfinal,

No. of Columns = 3 (Id, Latitudegeo, Longitudegeo)

8. Open new file in notepad++, save as web1.php.

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9. To find whether database is created or not,

i. Enter $mysql host = ‘local host’

ii. User = id5878428-testing.

iii. Password = testing.

iv. Data base name =id5878428-testing

10. Now create web2.php such that it gets Latitude and Longitude from our

database

11. Make the values in json format save as web3.php.

8.5 Accessing Database through Public URL.

1. Login to 000webhost.com

2. Click File Manager.

3. Create New Folder as api.

4. Upload the files of web1.php, web2.php, web3.php in api.

5. If we click and view web3.php, it would open as,

Blindstick.000webhostapp.com/api/web3.php

Fig 8.1 Public URL Displaying Location

6. It is public accessible URL, wherever we type this URL, we would get

updated database values

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8.6 Accessing Location through Android Studio.

1. Now Open Android Studio.

2. Change json_url=http://blindstick.000webhostapp.com/api/web3.php

3. Run the app on our phone,

4. On pressing CLICKME button, it would display the contents of json_url

5. This app is made as public accessible by everyone on any networks.

Fig 8.2 CLICKME Button pressed.

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CHAPTER 9

LOCATION TRACKING USING NODEMCU

9.1 Introduction

Yes it’s possible to get the location with just our tiny little ESP8266

board. We don’t need anything other than ESP board not even GPS module to get our

live co-ordinates. Yes but we do require one screen to display the co-ordinates. So how is

Geolocation using ESP8266 possible?

This is possible with Google’s Geolocation API.

9.2 Working of Google Geolocation

As you know google takes the input of our nearby WiFi routers and in

response gives us the coordinates. For that, google provides API and in that API

we need to provide some inputs like details of nearby wifi routers, detail of nearby

cell towers etc. Before using that API you need to get your API key working.

35

9.3 Getting API key

1. Go to http://developers.google.com/maps/documentation/geolocation/get-

api key

2. Enter project name as ESP8266.

3. Get API key which will be necessary to get location.

Fig 9.1 Displaying API key

4. Add the API key to the application.

https://www.googleapis.com/geolocation/v1/geolocate?key = API key.

5. In order to display the location, install the libraries “WiFiClientSource”,

“Arduino Json”, “Esp8266WiFi”.

6. In order to request URL, we need internet connection, connect with mobile’s

hotspot for that enter our hotspot name, password in code.

7. When WiFi is connected, it gets our nearby WiFi, routers, cell towers Mac

Address using NodeMCU.

8. When the URL is requested, it gives the latitude and longitude of our

location.

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CHAPTER 10

RESULT &CONCLUSION

10.1 Results

The stick is successfully integrated to detect obstacles using ultrasonic

sensor, water sensing using moisture sensor, stick finder using RF transmitter and

RF Receiver, Location tracking using NodeMCU and a application software is

created using Android Studio to access the blind people’s location.

Fig 10.1 Final Completed Setup

37

10.2 Conclusion

The goal of the ultrasonic walking stick for visually impaired is to reduce

the difficulty faced by the visually impaired while maintaining its affordable price.

Blind person’s location can be tracked whenever needed which will ensure

additional safety.

REFERENCES

[1] Microprocessor Architeture, Programming and Applications with 8085 –

Ramesh S Gaonkar

[2] Microprocessor and Interfacing, Programming and Hardware – Douglas V

Hall

[3] The 8051 Microcontroller and Embedded Systems – Muhammad Ali Mazidi

[4] Arduino : 101 Beginners Guide – Erik Savasgard

[5] https://circuitdigest.com/electronic-circuits/rf-transmitter-and

[6] http://www.instructables.com/id/How-To-Create-An-Android-App-With-

[7] https://howtomechatronics.com/tutorials/arduino/ultrasonic-sensor-hc- sr

[8] http://www.instructables.com/id/Arduino-Soil-Moisture-Sensor/

[9] https://electronicsforu.com/electronics-projects/gps-geolocation-using-

esp8266-projects