APPENDIX 1

An Intelligent Mobile Robot Navigation Technique

Using RFID Technology

A PROJECT REPORT

Submitted by

M.MANIKANDESHWAR(121021066)

J.MURALIDHARAN(121021076)

S.PRADEEP (121021089)

In partial fulfillment of the requirements

for the award of the degree

of

BACHELOR OF ENGINEERING

in

ELECTRONICS AND COMMUNICATION ENGINEERING

MONTH & YEAR

APRIL 2016

SRI KRISHNA COLLEGE OF

ENGINEERING AND TECHNOLOGY (An Autonomous Institution)

(Approved by AICTE and Affiliated to Anna University, Chennai)

ACCREDITED BY NAAC WITH “A” GRADE

APPENDIX 2

SRI KRISHNA COLLEGE OF ENGINEERING AND TECHNOLOGY (An Autonomous Institution)

(Approved by AICTE and Affiliated to Anna University, Chennai)

ACCREDITED BY NAAC WITH “A” GRADE

BONAFIDE CERTIFICATE

Certified that this project report “An Intelligent Mobile Robot Navigation

Technique Using RFID Technology”is the bona fide work of “S.PRADEEP

M.MANIKANDESHWAR AND J.MURALIDHARAN” who carried out the

project work under my supervision.

SIGNATURE

DR.H.MANGALAM.,PHD.,

PROFESSOR AND HEAD

DEPARTMENT OF ELECTRONIC

AND COMMUNICATION

ENGINEERING

SRI KRISHNA COLLEGE OF

ENGINEERING AND TECHNOLOGY

COIMBATORE

SIGNATURE

DR.S.SOPHIA.,PHD.,

SUPERVISOR

PROFESSOR

DEPARTMENT OF ELECTRONIC AND

COMMUNICATION ENGINEERING

SRI KRISHNA COLLEGE OF

ENGINEERING AND TECHNOLOGY

COIMBATORE

This project report submitted for the Autonomous Project Viva-voce examination

held on____________

INTERNAL EXAMINER EXTERNAL EXAMINER

Abstract

The new indoor navigation system we have proposed allows model user to

be guided to a desired location on his own, as long as the building itself is adopted

to the novel system. Unlike the state of the art, where no automation exists for

guiding a system in modern buildings, this allows the owner of the least

sophisticated design to explore public buildings with more ease than a normal

person. In this project we intend to implement a working prototype model based on

four RF ID tag with Line follower setup. The APR voice kit is used to record the

user voice and storing purpose. These prototypes are designed with the help of two

ardiuno uno board for transmitting and reception respectively.

APPENDIX 3

TABLE OF CONTENTS

CHAPTER NO

1

2

3

4

TITLE

ABSTRACT

LIST OF TABLES

LIST OF FIGURES

LIST OF SYMBOLS

INTRODUCTION

COMPONENTS OF THE SYSTEM

2.1 INTRODUCTION

2.2 TRANSMITTER BLOCK

2.3 POWER SUPPLY UNIT

2.4 APR33A3BVOICE RECORDER UNIT

2.4.1 FEATURES

2.5 RECEIVER BLOCK

RF MODULE

3.1 INTRODUCTION

3.2 HT12E-ENCODER

3.3 OSCILLATOR PINS

3.4 VT PINS

3.5 FEATURES

3.5.1 ENCODER

3.5.2 DECODER

3.5.3 APPLICATION

3.6 TYPES OF RF MODULES

3.7 HT12E(RF ENCODER)

3.8 HT12D(RF DECODER)

PIC CONTROLLER

4.1 INTRODUCTION

4.2 CHARACTERISTIC OF THE RISK

PAGE NO

iii

vi

vii

viii

1

2

2

2

3

4

5

7

9

9

11

14

15

15

15

16

16

16

17

19

22

22

22

5

6

7

4.2.1 THE FIRST FAMILY, PIC10

4.2.2 THE SECOND FAMILY,PIC12

4.2.3 THE THIRD FAMILY, PIC16

4.2.4 THE FOURTH FAMILY, PIC17/18

4.3 CHOOSING/SELECTING A PIC

MICROCONTROLLER

4.4 PIC MICROCONTROLLER

4.5 HISTORY

4.6 DEVELOPMENT

4.7 PIN DESCRIPTION

4.8 PROGRAMMING THE PIC

4.9 PROCEDURE T FOLLOW

LCD

5.1 LCD DISPLAY

CONCLUSION AND FUTURE WORK

LITERATURE SURVEY

7.1 LOW-COST 3D SCENE RECONSTRUCTION FOR

RESPONSE ROBOTS IN REAL TIME

7.2 VISUAL NAVIGATION FOR MOBILE ROBOTS:A

SURVEY

7.3 AN ENVIRONMENT VISUAL FEATURES BASED

NAVIGATION FOR MOBILE ROBOT IN A

CORRIDOR ENVIRONMENT.

7.4 ROBUST OMNIDIRECTIONAL MOBILE ROBOT

TOPOLOGICAL NAVIGATION SYSTEM USING

OMNI DIRECTIONAL VISION

7.5 INCREMENTAL TOPOLOGICAL MAPPING USING

OMNIDIRECTIONAL VISION

7.6 DESIGN OF A SPRING MOUNTED 3-D RANGE

SENSOR WITH APPLICATION TO MOBILE

MAPPING

REFERENCE

22

23

23

23

23

24

25

25

26

29

30

31

31

34

35

35

35

36

36

37

37

38

LIST OF TABLES

TABLE NO

2.1

3.1

3.2

5.1

TITLE

PIN CONFIGURATION (APR33A3)

RF TRANSMITTER

RF RECEIVER

LCD DISPLAY FUNCTION DESCRIPTION

PAGE NO

5

10

10

32

LIST OF FIGURES

FIGURE NO

2.1

2.2

2.3

2.4

2.5

3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.8

3.9

4.1

4.2

4.3

5.1

5.2

TITLE

ARDUINO UNO

NEW INTERFACE

OLD INTERFACE

MINIMUM ORDER DIAGRAM

SAMPLE PROGRAM

RF MODULE

RF TRANSMITTER

PIN DIAGRAM HT12E

HT12E(TRANSMISSION SIDE)

HT12D(RECEIVER SIDE)

TRANSMISSION TIMING FOR HT12E

FLOW CHART FOR HT12E

RECEPTION TIMING FOR HT12D

FLOW CHART FOR HT12D

10 PIC MICROCONTROLLER

PIN DIAGRAM 16F877A

PIC 16 F877A ARCHITECTURE

LCD DISPLAY

EXAMPLE MODEL

PAGE NO

5

7

8

9

11

9

11

12

13

14

17

18

20

21

24

27

28

32

33

LIST OF ABBREVATION

GPS

RF

PIC

LED

ADC

DAC

OPAMP

BJT

ASK

CMOS

LSI

CPU

RISK

AVR

USB

CAN

LCD

CRT

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

Global Positioning System

Radio frequency

Peripheral Interface Controllers /Peripheral

Interface Controllers (PIC)

Light emitting diode

Analog Digital Converter

Digital Analog Converter

Operational Amplifier

Bipolar Junction Transistor

Amplitude Shift Keying

Complementary Metal Oxide Semiconductor

Large Scale Integration

Central Processing Unit

Reduced Instruction Set Control

Advanced Virtual Risk

Universal Serial Bus

Controller Area Network

Liquid Crystal Display

Cathode Ray Tube

1

CHAPTER 1

INTRODUCTION

An indoor positioning system (IPS) is a system to locate objects or people inside a

building using radio waves, magnetic fields, acoustic signals, or other sensory information

collected by mobile devices.[1] There are several commercial systems on the market, but there is

no standard for an IPS system.

IPS systems use different technologies, including distance measurement to nearby anchor

nodes (nodes with known positions, e.g., WiFi access points), magnetic positioning, dead

reckoning. They either actively locate mobile devices and tags or provide ambient location or

environmental context for devices to get sensed. The localized nature of an IPS has resulted in

design fragmentation, with systems making use of various optical, radio, or

even acoustic technologies. System designs must take into account that at least three independent

measurements are needed to unambiguously find a location .For smoothing to compensate

for stochastic (unpredictable) errors there must be a sound method for reducing the error budget

significantly. The system might include information from other systems to cope for physical

ambiguity and to enable error compensation.

.

2

CHAPTER 2

ARDUINO

2.1 INTRODUCTION

The transmitter and the receiver section of PIC micro-controller is shown below. This

is very important for the functioning of the system as a whole. The transmitter and the receiver

section is used for the data transmission and reception using RF which is encoded and decoded

for secure data transmission.A step-down transformer is used to regulate the power supply.The

voice recorder unit is used for audio conversion and detection.

2.2 ARDUINO IDE

The Integrated Development Environment (IDE) we use the Arduino IDE on your

computer to create, open, and change sketches (Arduino calls programs “sketches”. We will use

the two words interchangeably in this book.). Sketches define what the board will do. You can

either use the buttons along the top of the IDE or the menu items. Open-source electronic

prototyping platform allowing to create interactive electronic objects. The popularity of Arduino

is steadily increasing and it is fast becoming the microcontroller of choice for students, hobbyists

and smaller companies. Many different electronics PCB manufacturing companies are jumping

on the bandwagon and producing their own variations of the boards, as well as “shields”

(additional circuits that fit directly on top of many Arduino boards to increase their functionality)

and accessories. The Arduino website offers free resources and tutorials as well as a language

reference to help you understand the code and syntax. In order to get started, you will at the very

minimum need an Arduino board. Note that all the Arduino (and most of the clone boards) can

use the Arduino software. If you are unsure what hardware to get, the Arduino USB is currently

the most popular model, and these 5 minute tutorials are based around it.

2.2.1 HISTORY

Started in 2005 as a project for students at the Interaction Design Institute

Ivrea in Ivrea, Italy

Developed because other micro-controllers were quite expensive.

3

The Arduino core team consisted of Massimo Banzi, David Cuartielles, Tom Igoe,

Gianluca Martino and David Mellis.

2.2.2 Parts of the IDE: (from left to right, top to bottom)

• Compile - Before your program “code” can be sent to the board, it needs

to be converted into instructions that the board understands. This process

is called compiling.

• Stop - This stops the compilation process. (I have never used this button

and you probably won’t have a need to either.)

• Create new Sketch - This opens a new window to create a new sketch.

• Open Existing Sketch - This loads a sketch from a file on your computer

2.2.2.1 Components Required

Step down transformer-1 (230V to 12V or 110V to 12V)

Diodes-4 (1N4007)

Capacitor-1 (470µF)

Led-1 (Red)

Resistor-1 (1K)

2.2.3 Advantages over other microcontrollers

Inexpensive

Arduino boards are relatively inexpensive compared to other microcontroller

platforms.

4

Cross-platform

The Arduino software runs on Windows, Macintosh OSX, and Linux operating

systems.

Simple, clear programming environment

The Arduino programming environment is easy-to-use for beginners, yet flexible

enough for advanced users to take advantage of as well.

Open source and extensible software

The Arduino software is published as open source tools. The language can be

expanded through C++ libraries, and people wanting to understand the technical

details can make the leap from Arduino to the AVR C programming language on

which it's based.

Open source and extensible hardware

2.3 Arduino UNO

2.3.1 Characteristics

The Arduino Uno is a microcontroller board based on the ATmega328

It has 14 digital input/output pins (of which 6 can be used as PWM

outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB

connection, a power jack, an ICSP header, and a reset button.

5

Simply connect it to a computer with a USB cable or power it with a AC-

to-DC adapter or battery to get started.

"Uno" means one in Italian and is named to mark the upcoming release of Arduino

1.0.

2.3.2 Details

The Arduino Uno can be powered via the USB connection or with an

external power supply. The power source is selected automatically.

The Arduino Uno has a number of facilities for communicating with a

computer, another Arduino, or other microcontrollers.

Figure 2.1 Arduino UNO

6

Therefore now we know that arduino is a free open source hardware and software developing

company that facilitates the people with its various microcontrollers that help an individual to

explore the world of electronics with just a little knowledge. In addition Arduino being cheap

is affordable. Similarly it works on various other platforms like Mac OS, Linux and

Windows obviously. So we can conclude that Arduino is the most reliable, efficient and

affordable microcontrollers for the beginners.

2.3.3 Downloading / Installing Arduino Software

1. Go to www.arduino.cc to download the latest version of the Arduino software (Direct

link: http://arduino.cc/en/Main/Software and select your operating system; in this case we

are using Windows)

2. Save the ZIP file to your desktop (you can move or delete it later)

3. It is convenient to create a new folder called “Arduino” under “Program Files”. To do

this, go to “My computer” -> “C:” (or the drive where the operating system is installed) -

> “Program Files”, then left click once on “program Files” folder, then select “New”-

>”Folder” from the main Explorer menu.

4. Extract the entire ZIP folder to this new “Arduino” folder

5. To run the Arduino software, open Windows Explorer by pressing the windows key

(usually between the Ctrl and Alt keys on your keyboard) and the ‘E’ character at the

same time (there are other ways to access explorer as well).

6. Go to “My computer” -> “C:” (or the drive where the operating system is installed) ->

“Program Files” -> “Arduino” In this folder you will see an executable file (blue colored

icon named “Arduino”), you can left click (once) and then right click and select “send to”

-> Desktop (create shortcut) to have Arduino more easily accessible.

7. Double click the icon on the desktop to start the software.

2.2.4 The Arduino Software Interface

The Arduino interface is pretty “bare-bones”. When you load the software, the first screen you

will see is a white window (shown below) with several different shades of blue and blue-green as

7

border. Arduino projects are called “sketches” and when you start a new sketch, several

additional files are also created.

2.3.4.1 “Newest: Arduino Interface (as of 2012)

The main headings are “File” “Edit” “Sketch” “Tools” “Help” and several shortcut icons beneath

“Verify”, “Upload”, “New”, “Open”, “Save”, and at the far right, the “Serial Monitor”. Note that

all these icons are also available from the main menus.

Figure 2.2 New Interface

8

2.3.4.2“Older” Arduino Interface

The main headings are “File” “Edit” “Sketch” “Tools” “Help” and several shortcut icons beneath

“Verify”, “Stop”, “New”, “Open”, “Save”, “Upload” and “Serial Monitor”. Note that all these

icons are also available from the main menus.

Figure 2.3 Older Interface

9

To connect to your board,

1. Launch the Arduino software by double-clicking the Arduino icon

2. Plug one end of the USB into the Arduino and the other end into your computer.

3. Your computer should detect the new device and tell you if it has installed correctly. At

this time, two things can happen; if you have an older board using an FTDI chip (ex.

Duemilanove based), Windows should detect it and you’re good to go to the next step. If

you have a board which uses an ATMega chip to convert USB to serial (for example the

UNO), you will need to install the drivers manually.

4. Take a look at your board’s main processor chip (usually found between the pin headers)

to see which you have. It will likely be the ATMega168, ATMega328, or a more

powerful ATMEga640. ATMega1280 etc

5. In the software, select “Tools” -> “Board” -> You will get a list of possible boards. If you

have a different board, select it from the drop-down list; if you have purchased a

compatible board, that manufacturer should indicate which board to choose.

6. In the software, select “Tools” -> “Serial Port” -> COM # (note that if you have several

COM ports, you will need to go to Device Manager to see which COM port is assigned to

your board.

The Arduino language is CASE SENSITIVE: a capital letter is not the same as a lower case

letter. The following code represents the minimum in order for a program to compile:

Fig 2.4 Minimum Order Diagram

10

The “void setup()” section is widely used to initialize variables, pin modes, set the serial baud

rate and related. The software only goes though the section once.

The “void loop()” section is the part of the code that loops back onto itself and is the main part

of the code. In the Arduino examples, this is called “Bare Minimum” under File-> Examples ->

Basics. Note that you are free to add subroutines using the same syntax:

void subroutinename() {}

Almost every line of code needs to end with a semicolon ‘;’ (there are a few exceptions which

we will see later). To write single line comments in the code, type two back slashes followed by

the text:

//comments are overlooked when compiling your program

To write multi-line comments, start the comment with /* and end with */

/* This is a multi-line comment and saves you having to always use double slashes at the

beginning of every line. Comments are used used to explain the code textually. Good code

always has a lot of comments.*/

2.3.5 Serial Communication

The Arduino board can communicate at various baud (“baud rates”). A baud is a measure of how

many times the hardware can send 0s and 1s in a second. The baud rate must be set properly for

the board to convert incoming and outgoing information to useful data. If your receiver is

expecting to communicate at a baud rate of 2400, but your transmitter is transmitting at a

different rate (for example 9600), the data you get will not make sense. To set the baud rate, use

the following code:

void setup() {

Serial.begin(9600);

}

11

9600 is a good baud rate to start with. Other standard baud rates available on most Arduino

modules include: 300, 1200, 2400, 4800, 9600, 14400, 19200, 28800, 38400, 57600, or 115200

and you are free to specify other baud rates. To output a value in the Arduino window, consider

the following program:

Fig 2.5 A Sample Program

Verify the program by pressing the “verify” button (looks like a “play” button in order

version or a check sign in Arduino 1.0); you should not get any errors at the bottom of the

12

screen. If you get errors, check that only the two numbers in the code are black, the rest of the

text should have been automatically recognized and assigned a color. If part of the text is black,

check the syntax (often copy/pasting text from another program can include unwanted

formatting) and capitalization.

Next, upload the sketch to the board using the “Upload to I/O Board” button (arrow pointing

right). Wait until the sketch has finished uploading. You will not see anything unless you then

select the “Serial Monitor” button (rectangle with a circle that looks like a TV in the old

software, or what looks like a magnifying glass in the new software). When you select the serial

monitor, make sure the baud rate selected is the same as in your program. If you want to save all

your programs, we suggest creating a new folder called “reference” and save this program as

Hello World.

13

CHAPTER 3

APR33A VOICE RECORDER

3.1 APR33A3 VOICE RECORDER UNIT

The APR33A series are powerful audio processor along with high performance audio

analog-to-digital converters (ADCs) and digital-to-analog converters (DACs). The aPR33A

series are a fully integrated solution offering high performance and unparalleled integration with

analog input, digital processing and analog output functionality. The aPR33A series incorporates

all the functionality required to perform demanding audio/voice applications. High quality

audio/voicesystems with lower bill-of-material costs can be implemented with the aPR33A series

because of its integrated analog data converters and full suite of quality-enhancing features such

as sample-rate convertor. The aPR33A series C2.0 is specially designed for simple key trigger,

user can record and playback the message averagely for 1, 2, 4 or 8 voice message(s) by switch,

It is suitable in simple interface or need to limit the length of single message, e.g. toys, leave

messages system, answering machine etc. Meanwhile, this mode provides the power-

management system. Users can let the chip enter power-down mode when unused. It can

effectively reduce electric current consuming to 15uA and increase the using time in any projects

powered by batteries.The PIN diagram configuration of APR33A3 is shown below in Fig.2.3.

along with the PIN configuration in Table 2.1

Figure 3.1 APR33A3 VOICE RECORDER KIT

14

Figure 3.2 PIN DIAGRAM

Pin Names Pin No TYPE Description

VDDP

VDD

VDDA

VDDL

8

10

18

24

Positive power supply.

VSSP

VSSL

VSSA

5

11

17

Power ground.

VLDO 25 Internal LDO output.

VCORE 16 Positive power supply for core.

VREF 19 Reference voltage.

VCM 20 Common mode voltage.

Rosc 26 INPUT Oscillator resistor input.

RSTB 27 INPUT Reset. (Low active)

APR33A3

15

SRSTB 28 INPUT System reset, pull-down a resistor to the VSSL.

MIC+

MIC-

21

22

INPUT

Microphone differential input.

MICG 23 OUTPUT Microphone ground.

VOUT1

7

INPUT PWM output to drive speaker directly.

DAC option.

VOUT2

6

INPUT PWM output to drive speaker directly.

DAC output.

/REC 12 INPUT Record Mode. (Low active)

M0 13 INPUT Message-0.

M1 14 INPUT Message-1.

M2 15 INPUT Message-2.

M3 9 INPUT Message-3.

M4 3 INPUT Message-4.

M5 4 INPUT Message-5.

M6 / MSEL0 1 INPUT Message-6, Message select 0.

M7 / MSEL1 2 INPUT Message-7, Message select 1.

Table 3.1 PIN CONFIGURATION

FIG 3.3 CIRCUIT DIAGRAM

16

3.2 Steps For Recording Voice

1. We can use 8 channels(M0 TO M7)each channel having 1.3minutes recording length.

Onboard MIC will automatically be used for recording.

2. Supply voltage:12v AC/DC.

3. Switch on the board power LED(LD1)will on.

4. Put the jumper in the board JP1(REC)Section.

5. While in record mode select J5(M0-M7) to select a channel to record the message.

6. Let us assume we want to record message in channel M0,Connect M0 to GND(IN Board

J3-VCC,GND).

Now whatever we Speak will be captured by MIC and recorded, status LED (LD2) will on in

record mode indicating that chip is currently recording. Once duration is full the LED (LD2) will

off means that segment is full. Now you can disconnect the GND Connection from M0,if before

the duration is this connection is removed, then that many seconds are recorded and rest duration

is kept empty.

3.3 To Playback recorder message

1.Connect the speaker to the board J4 Speaker section.

2.NOW let us check what we recorded.remove jumper from JP1(REC)section

now connect the MO(J5)to GND(J3)Section, status LED(LD2) will ON till the recorded sound

play in the speaker.

"This procedure same for the remaining channels also"

3.4 To use with Microcontroller

Better Do Voice Recording can be done Manually

To play back connect Controller I/Os to M0 to M7

When Output Goes Low For particular Pin Recorded message will play.

17

Fig 3.4 INTERFACED WITH A MICRO-CONTROLLER

FIGURE 3.5 BLOCK DIAGRAM -WORKING

18

3.5 FEATURES

Operating Voltage Range: 3V ~ 6.5V

Single Chip, High Quality Audio/Voice Recording & Playback Solution

No External ICs Required

Minimum External Components

User Friendly, Easy to Use Operation

Programming & Development Systems Not Required

170/ 340/ 680 sec. Voice Recording Length PR33A1/ aPR33A2

Powerful 16-Bits Digital Audio Processor.

Nonvolatile Flash Memory Technology

No Battery Backup Required

External Reset pin.

Powerful Power Management Unit

Very Low Standby Current: 1uA

Low Power-Down Current: 15uA

Supports Power-Down Mode for Power Saving

Built-in Audio-Recording Microphone Amplifier

No External OPAMP or BJT Required

Easy to PCB layout

Configurable analog interface

Differential-ended MIC pre-amp for Low Noise

High Quality Line Receiver

High Quality Analog to Digital and PWM module

Resolution up to 16-bits

Simple And Direct User Interface

19

CHAPTER 4

RADIO FREQUENCY IDENTIFICATION

4.1 INTRODUCTION

The RF module, as the name suggests, operates at Radio Frequency. The RF transmitter and

Receiver system is shown below in figure 3.1.The frequency range varies between 30 kHz & 300

GHz. In this RF system, the digital data is represented as variations in the amplitude of carrier

wave. This kind of modulation is known as Amplitude Shift Keying (ASK). The RF module we

will use comprises of an RF Transmitter and an RF Receiver. The transmitter/receiver (Tx/Rx)

pair operates at a frequency of 433 MHz and it has 4 output pins i.e. it can operate 4 peripherals

remotely. The RF module is often used along with a pair of encoder/decoder. The encoder is

used for encoding parallel data for transmission feed while reception is decoded by a decoder.

4.2 HISTORY

In 1974, bar codes were first used to read price tags on groceries in supermarkets. Today, billions

and billions of bar codes are scanned every day for a huge variety of uses beyond purchasing

products (Shih). Bar codes are used to record prices for purchases, track millions of pieces of

mail at the US Postal Service, identify patients in hospitals, manufacture goods, and more. Bar

codes are everywhere in our global economy, but will they be replaced with a system that uses

newer technologies? Radio Frequency Identification (RFID) tags use wireless technology and

offer some benefits over bar codes. “RFID uses a method of remotely storing and retrieving data

using a small object attached to or incorporated into a product.” RFID tags can store more

information than a bar code and do not need to be scanned. Both bar codes and RFID offer

benefits and drawbacks; time will tell whether they will continue to coexist together, or whether

one will win out over the other.

Any consumer knows what a bar code looks like. “A bar code is a series of parallel black bars

and white spaces, both of varying widths.” (Inman) A bar code can be decoded to provide a

unique reference number to particular item that can then be looked up by a computer. No other

information about the item is stored in the bar code; it contains only a unique reference number.

Any information about the product or item is stored elsewhere; not on the bar code itself.

20

A bar code must be scanned by a bar code reader. For instance, at the grocery store each grocery

item with a bar code must be swiped over a bar code reader until it is recognized, usually with a

beep sound. Until recently bar codes were used only in business or retail settings. Japan was the

first country where it was possible for consumers to use cameras on cell phones as bar code

scanners. As Louise Story reported in 2007 in The New York Times:

Consumers can already point their cellphones at the wrapping on their hamburgers and get

nutrition information on their screens. Users there can also point their phones at magazine ads to

receive insurance quotes, and board airplanes using their phones rather than paper tickets. And

film promoters can send their movie trailers from billboards.

Smart phone appsthat scan bar codes are widely used by consumers today. In 2009 ShopSavvy

released an application that allows iPhone users to point their iPhone cameras at a bar code, scan

it, and then display product information including product reviews and where to get the best deal

in your area. (Hertz) The San Francisco companyGoodGuide released the first application for the

iPhone that allows users to use their iPhone camera to capture bar codes to get rating information

on how eco-friendly a product is. (Moore)

One of the biggest benefits of bar codes is that they are inexpensive. Adding a bar code to a

product costs just a half a cent. (Shih)Another benefit to using bar codes is that they are in place

now and used virtually everywhere. (Inman)All the infrastructure to manufacture, read, and use

bar codes is in place now; switching to a new system, even one that has greater benefits, would

be costly.

RFID tags provide many advantages over bar codes. An RFID tag is a tiny device that emits a

signal, which is transmitted, read by an RFID reader, and then transmitted to a network for

processing. RFID can store much more information than bar codes. For instance, RFID tags can

store information about location, or detailed information about the contents of a product. RFID

tags do not need to be individually scanned (as bar codes do); hundreds of RFID tags can be read

at once. RFID tags can also store information that is unique to a particular item. (Inman)

RFID tags are used today for a variety of purposes. They can be used to manage inventory, track

the location of shipments, collect tolls at toll booths, or monitor the location of prisoners in

prisons. (Inman) The Federal government has recommended that RFID tags be used to track

livestock; doing so would enable speedy and efficient recalls of meat associated with a particular

21

diseased animal. (Eckholm) RFID tags are also frequently used to monitor medical devices in

hospitals.

The RFID Journal reports that Europe’s adoption of RFID technology is on the rise, even though

they are suffering difficult economic times. RFID is now seen as an immediate solution that can

boost productivity and increase cost savings. (Edwards)

Although there are benefits to using RFID tags, there are controversies and obstacles, too. First,

they are much more expensive than bar codes. While bar codes cost just a half a cent each, RFID

tags cost five cents or more. (Shih) Adopting the use of RFID tags would require updating

systems and infrastructure to allow for their use. There is also controversy about the use of RFID

tags in hospitals. Eric Nagourney writing for The New York Times reported that signals from

RFID tags are interfering with critical care equipment in hospitals. (Nagourney)

Privacy advocates are also concerned about the widespread use of RFID tags. RFID systems are

now being promoted to schools as a way to inventoried items such as books or equipment. Two

Middle schools in San Antonio, TX require students to wear RFID tag on their ID cards, for the

stated purpose of being able to track attendance and get more money from the state. (Sullivan)

However, the systems are a privacy threat because they could also be used to track students’

attendance as well as their movements. Tracking people using RFID is widely seen as

dehumanizing activity that violates people’s privacy and inhibits their freedom of speech.

(Rezmiersky, Judith McGeary and Griffin)

Bar codes are the most common system for tracking items used today. Now that consumers can

access information from a bar code using their cell phones, bar codes connect consumers with

information about products while they are on the go. Because bar codes are so inexpensive, they

are likely to remain in use for a while. RFID tags offer benefits that extend beyond those of bar

codes. Although the use of RFID tags will continue to growfor RFID tags might not replace bar

codes due to their high cost and privacy concerns.

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4.3 TRANSMITTER BLOCK

The transmitter unit is constructed by using a controller with a communication protocol

Universal serial Asynchronous Receiver and transmitter. The transmission Block Diagram is

shown is Fig 4.1

Figure 4.1: Transmitter block

23

Figure RF module

Table 4.1 RF Transmitter

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Figure 4.2 RF transmitter

The figure given above shows schematic diagram of transmitter using IC HT12E. As

shown in figure all the address lines A0-A7 are connected to ground. You can either connect all

the lines to Vcc or to ground but keep in mind that on the receiver side you have to do same. This

is to set same address both the sides. Resistor R1 (1.1Mohm) is connected between oscillator

pins (pin 15 & 16) to set transmitter frequency = 50×Receiver Frequency (see datasheet of

encoder and decoder). Data lines D0-D3 are connected with switches S0-S3. Data will be

transmitted only when the Transmit Enable pin (TE) is LOW. Operation:- Whenever you press

any key particular data line is grounded. Now we know when TE pin is low (TE-transmission

enable pin is low active) so the address and data are transmitted serially through DataOut pin

which is connected to data pin of the transmitter. If we press switch S0 then data word will be

1110 and address is of course 00000000

An RF module (radio frequency module) is a (usually) small electronic device used to

transmit and/or receive radio signals between two devices. In an embedded system it is often

desirable to communicate with another device wirelessly. This wireless communication may be

25

accomplished through optical communication or through radio frequency (RF) communication.

For many applications the medium of choice is RF since it does not require line of sight. RF

communications incorporate a transmitter and/or receiver.

4.4 RECEIVER BLOCK

The receiver block is made up of a RF receiver, a decoder circuit, a microcontroller along

with a voice built in with speaker and display unit. The RF receiver receives the signal which

is then decoded and passed onto the micro-controller. The micro-controller processes the

information and then transfers the message to the APR33A3 voice unit which states and

displays the message.

Figure 4.3 Receiver Block

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Table 4.2 RF Receiver

4.5 HT 12E Encoder

The HT 12E Encoder ICs are series of CMOS LSIs for Remote Control system

applications. They are capable of Encoding 12 bit of information which consists of N address

bits and 12-N data bits. Each address/data input is externally trinary programmable if bonded

out.

Figure 4.4 Pin diagram HT12E

The data could be anything like simple binary data (in the form of 1's and 0's) or it could

be an audio signal or it could be certain text. But here we are dealing with the encoding that is

used for binary signals. The wrapped data is called as a Packet. This packet is sent through a

medium (“Through wire or wireless”) to the decoder part where it gets unwrapped or decoded.

Yes, now what you are thinking is right, it is exactly similar to posting an envelope. Encoding is

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when you put the letter into envelope, the postman is medium to take the envelope to the

recipient and when recipient opens the envelope then it is called decoding.

Let’s first take the Encoding side. The encoder has four input lines. Theses lines are used

to give input which we want to encode. In encoding, we are wrapping up the data which means if

we want to send a binary signal ‘1001’ to other end, we have to make data pins as ‘1001’. Now,

to make data pin like this, what we need to do is to give high or 5 volts (which in digital means

‘1’) to pins ‘D0’ and ‘D3’ while we have to provide pins ‘D1’ and ‘D2’ with 0 volt. (Ground).

This altogether gives us ‘1001’ which is transmitted out from the ‘Data out’ pin of the HT12E.

The input given to data pin is in parallel form which is being transmitted into serial form from

the data output pin.

Figure 4.5 HT12E(Transmitter side)

Our data is now been encoded and will be transmitted. The transmission medium could

be anything, it could be our regular wire, or wireless. In this tutorial, we are going to use our

steady single core wire which we use to provide connections in breadboard (nothing fancy).The

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data flows in serial form through the wire and reaches the other end i.e. to the receiver. Receiver

now decodes this signal.

Figure 4.6 HT12D (Receiver side)

Now neglect all the pins for this moment and just concentrate on Din (Data in) pin and

the for Data lines pin. The encoded data which is coming from the transmitter side goes into the

Data in (Din) pin. The data which was in serial order gets decoded and the output is generated at

the for data line pins in same order as that on transmitter pin.

4.6 Oscillator Pins:

When we first hear the word oscillations, the first thing that comes in our mind is the to

and fro waving motion, yup as always you are correct. The role of oscillator in digital electronics

is to produce waves which are in Sine wave form or rectangular wave form. The device used to

generate this waveform is called ‘Oscillator’. The waveform generated by the oscillator is called

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as ‘Pulses’ (like our heart beat). So, in digital world the oscillator works identical to our Heart.

Unfortunately, we will not be able to see the oscillator device itself because in HT12D and

HT12E, the oscillator comes inbuilt, what we have to do is to put a resistor between the

oscillators pins. But, in our coming tutorial over microcontrollers, the need of oscillator is must,

so we will learn about it in that tutorials only.

4.7 VT Pin (Valid Transmission):

The valid transmission pin in decoder shows that the transmitter address and the receiver

address are same and is ready to receive the data from the encoder side.During implementation

of the circuit, we will see how to get notification about the valid transmission through this

pin.So, now we are loaded with all the essentials needed to implement Encoder-Decoder circuit.

Let’s start implementing one:

4.7.1 Components Required:

1. IC- HT12E/HT12D (generally comes in pair).

2. Breadboard with complete Power supply.

3. LEDs (5)

4. Resistors (Four 125 ohm for LEDs)

(750k ohm for oscillator of Encoder)

(27k ohm for oscillator of Decoder).

5. Reset Switch (4).

6. Battery (6-24 volts)

4.8 Features

4.8.1 Encoder

18 PIN DIP

Operating Voltage : 2.4V ~ 12V

Low Power and High Noice Immunity CMOS Technology

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Low Standby Current and Minimum Transmission Word

Built-in Oscillator needs only 5% Resistor

Easy Interface with and RF or an Infrared transmission medium

Minimal External Components

4.8.2 Decoder

18-pin DIP

Operating Voltage : 2.4V ~ 12.0V

Low Power and High Noise Immunity, CMOS Technology

Low Stand by Current : 0.1uA (typ.) at VDD=5V

Capable of Decoding 12 bits of Information

8 ~ 12 Address Pins and 0 ~ 4 Data Pins

4.8.3 Applications

Burglar Alarm, Smoke Alarm, Fire Alarm, Car Alarm, Security System

Garage Door and Car Door Controllers

Cordless telephone

Other Remote Control System

The HT 12D ICs are series of CMOS LSIs for remote control system applications. This

ICs are paired with each other. For proper operation a pair of encoder/decoder with the same

number of address and data format should be selected. The Decoder receive the serial address

and data from its corresponding decoder, transmitted by a carrier using an RF transmission

medium and gives output to the output pins after processing the data.

4.9 Types of RF modules

The term RF module can be applied to many different types, shapes and sizes of small

electronic sub assembly circuit board. It can also be applied to modules across a huge variation

of functionality and capability. RF modules typically incorporate a printed circuit board, transmit

or receive circuit, antenna, and serial interface for communication to the host processor.

Most standard, well known types are covered here:

Transmitter module

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Receiver module

Transceiver module

System on a chip module

4.10 HT12E (RF Encoder)

18-pin DIP

Operating Voltage : 2.4V ~ 12V

Low Power and High Noise Immunity, CMOS Technology

Low Standby Current : 0.1uA (typ.) at VDD=5V

Minimum Transmission Word = 4

Built-in Oscillator needs only 5% Resistor

Data code has positive polarity

Easy Interface with and RF or an Infrared transmission medium

Secure and robust protocol

Ideal for remote control and security applications

Compatible with the HT12D decoder IC

Minimal External Components

HT12E starts working with a low signal on the TE pin. After receiving a low signal the

HT12E starts the transmission of 4 data bits as shown in the timing diagram below. And the

output cycle will repeats based on the status of the TE pin in the IC. If the TE pin retains the low

signal the cycle repeats as long as the low signal in the TE pin exists. The encoder IC will be in

standby mode if the TE pin is disabled and thus the status of this pin was necessary for encoding

process. The address of these bits can be set through A0 – A7 and the same scheme should be

used in decoders to retrieve the signal bits.

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Figure 4.7 Transmission Timing for HT12E

Figure 4.8 Flow chart HT12E

33

3.10.1 Applications of Encoder

Burglar alarm system

Smoke and fire alarm system

Garage door controllers

Car door controllers

3.11 HT12D (RF Decoder)

18-pin DIP

Operating Voltage : 2.4V ~ 12.0V

Low Power and High Noise Immunity, CMOS Technology

Low Stand by Current : 0.1uA (typ.) at VDD=5V

Capable of Decoding 12 bits of Information

8 ~ 12 Address Pins and 0 ~ 4 Data Pins

Received Data are checked 3 times

Built in Oscillator needs only 5% resistor

VT goes high during a valid transmission

Easy Interface with an RF or an Infrared transmission medium

Secure and robust protocol

Ideal for remote control and security applications

Compatible with the HT12E encoder IC

Minimal External Components

HT12D decoder will be in standby mode initially ie, oscillator is disabled and a HIGH on DIN

pin activates the oscillator. Thus the oscillator will be active when the decoder receives data

transmitted by an encoder. The device starts decoding the input address and data. The decoder

matches the received address three times continuously with the local address given to pin A0 –

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A7. If all matches, data bits are decoded and output pins D8 – D11 are activated. This valid data

is indicated by making the pin VT (Valid Transmission) HIGH. This will continue till the

address code becomes incorrect or no signal is received.

Figure 4.9 Reception Timing for HT12D

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Figure 4.10 Reception Flow Chart for HT12D

36

CHAPTER 5

HM2007

5.1 INTRODUCTION:

Speech recognition will become the method of choice for controlling appliances, toys, tools and

computers. At its most basic level, speech controlled appliances and tools allow the user to

perform parallel tasks (i.e. hands and eyes are busy elsewhere) while working with the tool or

appliance. The heart of the circuit is the HM2007 speech recognition IC. The IC can recognize

20 words, each word a length of 1.92 seconds.

The onboard 3V battery is used to store the RAM content even after power off so if you store the

training words it remains after power off. Else you have to train board again after each power up.

Some people thing 3V battery powers the board but its not the case. You need to give external

voltage to power the board.

Fig 5.1 HM2007 BOARD

The speech recognition system is a completely assembled and easy to use programmable speech

recognition circuit. Programmable, in the sense that you train the words (or vocal utterances) you

37

want the circuit to recognize. This board allows you to experiment with many facets of speech

recognition technology. It has 8 bit data out which can be interfaced with any microcontroller for

further development.

Some of interfacing applications which can be made are controlling home appliances, robotics

movements, Speech Assisted technologies, Speech to text translation, and many more.

5.2 Working

The keypad and digital display are used to communicate with and program the HM2007 chip.

The keypad is made up of 12 normally open momentary contact switches. When the circuit is

turned on, “00” is on the digital display, the red LED (READY) is lit and the circuit waits for a

command.

Fig 5.2 HM2007 Board Schematic

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5.2.1 Training Words for Recognition

Press “1” (display will show “01” and the LED will turn off) on the keypad, then press the

TRAIN key ( the LED will turn on) to place circuit in training mode, for word one. Say the target

word into the onboard microphone (near LED) clearly. The circuit signals acceptance of the

voice input by blinking the LED off then on. The word (or utterance) is now identified as the

“01” word. If the LED did not flash, start over by pressing “1” and then “TRAIN” key.

You may continue training new words in the circuit. Press “2” then TRN to train the second

word and so on. The circuit will accept and recognize up to 20 words (numbers 1 through 20). It

is not necessary to train all word spaces. If you only require 10 target words that’s all you need to

train.

5.2.2 Testing Recognition:

Repeat a trained word into the microphone. The number of the word should be displayed on the

digital display. For instance, if the word “directory” was trained as word number 20, saying the

word “directory” into the microphone will cause the number 20 to be displayed.

5.2.3 Error Codes:

The chip provides the following error codes.

55 = word to long

66 = word to short

77 = no match

5.2.4 Clearing Memory

To erase all words in memory press “99” and then “CLR”. The numbers will quickly scroll by on

the digital display as the memory is erased.

5.2.5 Changing & Erasing Words

Trained words can easily be changed by overwriting the original word. For instances suppose

word six was the word “Capital” and you want to change it to the word “State”. Simply retrain

39

the word space by pressing “6” then the TRAIN key and saying the word “State” into the

microphone.

If one wishes to erase the word without replacing it with another word press the word number (in

this case six) then press the CLR key. Word six is now erased.

5.2.6 Simulated Independent Recognition

The speech recognition system is speaker dependant, meaning that the voice that trained the

system has the highest recognition accuracy. But you can simulate independent speech

recognition.

To make the recognition system simulate speaker independence one uses more than one word

space for each target word. Now we use four word spaces per target word. Therefore we obtain

four different enunciation’s of each target word. (speaker independent). The word spaces 01, 02,

03 and 04 are allocated to the first target word. We continue do this for the remaining word

space. For instance, the second target word will use the word spaces 05, 06, 07 and 08. We

continue in this manner until all the words are programmed.

If you are experimenting with speaker independence use different people when training a target

word. This will enable the system to recognize different voices, inflections and enunciation's of

the target word. The more system resources that are allocated for independent recognition the

more robust the circuit will become.

If you are experimenting with designing the most robust and accurate system possible, train

target words using one voice with different inflections and enunciation's of the target word.

5.2.6 Homonyms

Homonyms are words that sound alike. For instance the words cat, bat, sat and fat sound alike.

Because of their like sounding nature they can confuse the speech recognition circuit. When

choosing target words for your system do not use homonyms.

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5.2.7 The Voice with Stress & Excitement

Stress and excitement alters ones voice. This affects the accuracy of the circuit’s recognition. For

instance assume you are sitting at your workbench and you program the target words like fire,

left, right, forward, etc., into the circuit. Then you use the circuit to control a flight simulator

game, Doom

or Duke Nukem. Well, when you’re playing the game you’ll likely be yelling “FIRE! …Fire!

...FIRE!! ...LEFT …go RIGHT!”. In the heat of the action you’re voice will sound much

different than when you were sitting down relaxed and programming the circuit. To achieve a

higher accuracy word recognition one needs to mimic the excitement in ones voice when

programming the circuit.

These factors should be kept in mind to achieve the high accuracy possible from the circuit. This

becomes increasingly important when the speech recognition circuit is taken out of the lab and

put to work in the outside world.

5.2.8 Error Codes

When interfacing the external circuit through its data bus, The decoding circuit must recognize

the word numbers from error codes. So the circuit must be designed to recognize error codes 55,

66 and 77 and not confuse them with word spaces 5, 6 and 7.

5.2.9 Voice Security System

This circuit isn’t designed for a voice security system in a commercial application, but that

should not prevent anyone from experimenting with it for that purpose. A common approach is

to use three or four keywords that must be spoken and recognized in sequence in order to open a

lock or allow entry.

5.2.10 Aural Interfaces

It’s been found that mixing visual and aural information is not effective. Products that require

visual confirmation of an aural command grossly reduces efficiency. To create an effective AUI

products need to understand (recognize) commands given in an unstructured and efficient

methods. The way in which people typically communicate verbally.

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5.2.11 Learning to Listen

The ability to listen to one person speak among several at a party is beyond the capabilities of

today’s speech recognition systems. Speech recognition systems can not (as of yet) separate and

filter out what should be considered extraneous noise.

Speech recognition is not understanding speech. Understanding the meaning of words is a higher

intellectual function. Because a circuit can respond to a vocal command doesn’t mean it

understands the command spoken. In the future, voice recognition systems may have the ability

to distinguish nuances of speech and meanings of words, to “Do what I mean, not what I say!”

5.2.12 Speaker Dependent / Speaker Independent

Speech recognition is divided into two broad processing categories; speaker dependent and

speaker independent.

Speaker dependent systems are trained by the individual who will be using the system. These

systems are capable of achieving a high command count and better than 95% accuracy for word

recognition. The drawback to this approach is that the system only responds accurately only to

the individual who trained the system. This is the most common approach employed in software

for personal computers.

Speaker independent is a system trained to respond to a word regardless of who speaks.

Therefore the system must respond to a large variety of speech patterns, inflections and

enunciation's of the target word. The command word count is usually lower than the speaker

dependent however high accuracy can still be maintain within processing limits. Industrial

applications more often require speaker independent voice recognition systems.

5.2.13 Recognition Style

In addition to the speaker dependent/independent classification, speech recognition also contends

with the style of speech it can recognize. They are three styles of speech: isolated, connected and

continuous.

Isolated: Words are spoken separately or isolated. This is the most common speech recognition

system available today. The user must pause between each word or command spoken.

42

Connected: This is a half way point between isolated word and continuous speech recognition. It

permits users to speak multiple words. The HM2007 can be set up to identify words or phrases

1.92 seconds in length. This reduces the word recognition dictionary number to 20.

Continuous: This is the natural conversational speech we use to in everyday life. It is extremely

difficult for a recognizer to sift through the sound as the words tend to merge together. For

instance, "Hi, how are you doing?" to a computer sounds like "Hi,.howyadoin" Continuous

speech recognition systems are on the market and are under continual development.

5.3 More On The HM2007 Chip

The HM2007 is a CMOS voice recognition LSI (Large Scale Integration) circuit. The chip

contains an analog front end, voice analysis, regulation, and system control functions. The chip

may be used in a stand alone or CPU connected.

5.3.1 IC Features:

Single chip voice recognition CMOS LSI

Speaker dependent

External RAM support

Maximum 40 word recognition (.96 second)

Maximum word length 1.92 seconds (20 word)

Microphone support

Manual and CPU modes available

Response time less than 300 milliseconds

5V power supply

5.4 Applications

There are several areas for application of voice recognition technology.

Speech controlled appliances and toys

Speech assisted computer games

Speech assisted virtual reality

Telephone assistance systems

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Voice recognition security

CHAPTER 6

44

LCD

6.1 LCD Displays

A liquid-crystal display (LCD) is a flat panel display, electronic visual display, or video

display that uses the light modulating properties of liquid crystals.The PIN diagram of an LCD

display is shown in Fig 5.1. with its PIN configuration explained in Table 5.1. Liquid crystals do

not emit light directly. LCDs are available to display arbitrary images (as in a general-purpose

computer display) or fixed images with low information content which can be displayed or

hidden, such as preset words, digits, and 7-segment displays as in a digital clock. They use the

same basic technology, except that arbitrary images are made up of a large number of small

pixels, while other displays have larger elements.LCDs are used in a wide range of applications

including computer monitors, televisions, instrument panels, aircraft cockpit displays, and

signage. They are common in consumer devices such as DVD players, gaming devices, clocks,

watches, calculators, and telephones, and have replaced cathode ray tube (CRT) displays in

nearly all applications. They are available in a wider range of screen sizes than CRT and plasma

displays, and since they do not use phosphors, they do not suffer image burn-in. LCDs are,

however, susceptible to image persistence

The liquid-crystal display has the distinct advantage of having a low power consumption

than the LED. It is typically of the order of microwatts for the display in comparison to the some

order of milliwatts for LEDs. Low power consumption requirement has made it compatible with

MOS integrated logic circuit. Its other advantages are its low cost, and good contrast. The main

drawbacks of LCDs are additional requirement of light source, a limited temperature range of

operation (between 0 and 60° C), low reliability, short oper­ating life, poor visibility in low

ambient lighting, slow speed and the need for an ac drive.

5.2 Advantages of LCD display

Very compact and light.

Low power consumption.

Very little heat emitted during operation, due to low power consumption.

No geometric distortion.

45

Figure 6.1 LCD display

Table 6.1 LCD Display functional description

46

Figure 5.2 Example model

47

CHAPTER 7

CONCLUSION AND FUTURE WORK

The mobile robots are able to autonomously locate and navigate itself in the indoor

environment. Different from the outdoor environments where robots such as Google's

Autonomous Car can localize itself by GPS and navigate itself using the huge available

information like maps and vertices, in the indoor environments, the robot has to learn how to

localize and navigate itself without prior information. Indoor environments like office or

residential buildings generally consist of many rooms which are connected by corridors.

In this project the robot is localized and monitored by using RF antenna hence signal is

effectively monitoring and controlled by Arduino microcontroller. The main objective of this

project is to find the location of moveable unit with very low cost and there is no usage of GSM

or GPS.

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CHAPTER 8

LITERATURE SURVEY

8.1 Low-cost 3D scene reconstruction for response robots in real-time

Several methods for the creation of 3D models that can provide additional information to

robot operators in order to improve their situation awareness of the robot being teleoperated. We

derive the 3D models from spatial data gathered from an inexpensive, readily available, video

game sensor. In addition, the paper introduces a new method for feature extraction as part of

image registration in feature-sparse environments that operates in real-time. There are some

environments that are simply too dangerous for humans to work in. Typically such environments

are formed when catastrophic events create local conditions that are intolerable for humans.

Urban disasters often cause buildings to become unstable and quite dangerous. As work must

still be completed within these structures, emergency first responders have increasingly turned to

teleoperated response robots as effective tools. Response robots - controlled from a safe distance

- act as surrogates for humans. The effectiveness of this control is heavily dependent on the

remote operator’s perception and understanding of the situation that the robot is in when a

command is issued. It has been shown that establishing this perception and understanding is

typically a very challenging task.

8.2 Visual Navigation for Mobile Robots: a Survey

Mobile robot vision-based navigation has been the source of countless research

contributions, from the domains of both vision and control. Vision is becoming more and more

common in applications such as localization, automatic map construction, autonomous

navigation, path following, inspection, monitoring or risky situation detection. This survey

presents those pieces of work, from the nineties until nowadays, which constitute a wide progress

in visual navigation techniques for land, aerial and autonomous underwater vehicles. The paper

deals with two major approaches: map-based navigation and mapless navigation. Map-based

navigation has been in turn subdivided in metric map-based navigation and topological map-

based navigation. Our outline to mapless navigation includes reactive techniques based on

qualitative characteristics extraction, appearance-based localization, optical flow, features

49

tracking, plane ground detection/tracking, etc... The recent concept of visual sonar has also been

revised. Navigation can be roughly described as the process of determining a suitable and safe

path between a starting and a goal point for a robot travelling between them [18, 72]. Different

sensors have been used to this purpose, which has led to a varied spectrum of solutions. In

particular, in the last three decades, visual navigation for mobile robots has become a source of

countless research contributions since navigation strategies based on vision can increase the

scope of application of autonomous mobile vehicles. Among the different proposals, this paper

surveys the most recent ones. In many cases, the performance of a good navigation algorithm is

deeply joined to an accurate robot localization in the environment.

8.3 An environmental visual features based navigation for mobile robot in a corridor

environment

A navigation method that enables an autonomous mobile robot to localize itself and

identify its own orientation in order to follow a path in the environment. Both tasks use the same

recognition method. The method is based on features data provided through an image captured

by a single camera, which is trained by a neural network. No precise and accurate measurement

is used in the proposed navigation method, but the experiment results showed that the proposed

method is competent to work in actual environments.

8.4 Robust omnidirectional mobile robot topological navigation system using omni

directional vision

Robust topological navigation strategy for omnidirectional mobile robot using an

omnidirectional camera is described. The navigation system is composed of on-line and off-line

stages. During the off-line learning stage, the robot performs paths based on motion model about

omnidirectional motion structure and records a set of ordered key images from omnidirectional

camera. From this sequence a topological map is built based on the probabilistic technique and

the loop closure detection algorithm, which can deal with the perceptual aliasing problem in

mapping process. Each topological node provides a set of omnidirectional images characterized

by geometrical affine and scale invariant keypoints combined with GPU implementation. Given

a topological node as a target, the robot navigation mission is a concatenation of topological

node subsets. In the on-line navigation stage, the robot hierarchical localizes itself to the most

50

likely node through the robust probability distribution global localization algorithm, and

estimates the relative robot pose in topological node with an effective solution to the classical

five-point relative pose estimation algorithm. Then the robot is controlled by a vision based

control law adapted to omnidirectional cameras to follow the visual path.

8.5 Incremental Topological Mapping Using Omni-directional Vision

An algorithm that builds topological maps, using omnidirectional vision as the only

sensor modality. Local features are extracted from images obtained in sequence, and are used

both to cluster the images into nodes and to detect links between the nodes. The algorithm is

incremental, reducing the computational requirements of the corresponding batch algorithm.

Experimental results in a complex, indoor environment show that the algorithm produces

topologically correct maps, closing loops without suffering from perceptual aliasing or false

links. Robustness to lighting variations was further demonstrated by building correct maps from

combined multiple datasets collected over a period of 2 months.

8.6 Design of a Spring-Mounted 3-D Range Sensor with Application to Mobile Mapping

Three-dimensional perception is a key technology for many robotics applications,

including obstacle detection, mapping, and localization. There exist a number of sensors and

techniques for acquiring 3-D data, many of which have particular utility for various robotic tasks.

We introduce a new design for a 3-D sensor system, constructed from a 2-D range scanner

coupled with a passive linkage mechanism, such as a spring. By mounting the other end of the

passive linkage mechanism to a moving body, disturbances resulting from accelerations and

vibrations of the body propel the 2-D scanner in an irregular fashion, thereby extending the

device's field of view outside of its standard scanning plane. The proposed 3-D sensor system is

advantageous due to its mechanical simplicity, mobility, low weight, and relatively low cost. We

analyze a particular implementation of the proposed device, which we call Zebedee, consisting

of a 2-D time-of-flight laser range scanner rigidly coupled to an inertial measurement unit and

mounted on a spring. The unique configuration of the sensor system motivates unconventional

and specialized algorithms to be developed for data processing. As an example application, we

describe a novel 3-D simultaneous localization and mapping solution in which Zebedee is

51

mounted on a moving platform. Using a motion capture system, we have verified the positional

accuracy of the sensor trajectory.

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REFERENCES

[1] D. Fox, W. Burgard, and S. Thrun, “Markov localization for mobile robots in dynamic

environments,” J. Artif. Intell.Res., vol. 11, pp. 391–427, 1999.

[2] T. Rfer and M. Jngel, “Vision-based fast and reactive Monte-Carlo localization,” in Proc.

IEEE Int. Conf. Robot.Autom., 2003, pp. 856–861, IEEE.

[3] H. Du, P. Henry, X. Ren, M. Cheng, D. B. Goldman, S. M. Seitz, and D. Fox, “Interactive 3D

modeling of indoor environments with a consumer depth camera,” in Proc. 13th Int. Conf.

Ubiquitous Comput., New York, NY, USA, 2011, pp. 75–84.

[4] P. Henry, M. Krainin, E. Herbst, X. Ren, and D. Fox, “RGB-D mapping: Using kinect-style

depth cameras for dense 3D modeling of indoor environments,” Int. J. Robot. Res., vol. 31, pp.

647–663, 2012.

[5] F. Werner, J. Sitte, and F. Maire, “Topological map induction using neighbourhood

information of places,” Autonomous Robot., vol. 32, pp. 405–418, 2012.

[6] D. Marinakis and G. Dudek, “Pure topological mapping in mobile robotics,” IEEE Trans.

Robot., vol. 26, no. 6, pp. 1051–1064, Dec. 2012.

[7] S. Thrun, “Learning metric-topological maps for indoor mobile robot navigation,”

Artif.Intell., vol. 99, no. 1, pp. 21–71, 2012.

[8] G. N. DeSouza and A. C. Kak, “Vision for mobile robot navigation: A survey,” IEEE Trans.

Pattern Anal. Mach. Intell., vol. 24, no. 2, pp. 237–267, Feb. 2002.

[9] F. Bonin-Font, A. Ortiz, and G. Oliver, “Visual navigation for mobile robots: A survey,” J.

Intell. Robot.Syst., vol. 53, pp. 263–296, 2012.

[10] J. Tran, A. Ufkes, M. Fiala, and A. Ferworn, “Low-cost 3D scene reconstruction for

response robots in real-time,” Robotics, pp. 161–166, 2011.