1

Acknowledgement

We would like to take this opportunity to express our thanks and gratitude to all the persons

who have directly or indirectly availed us in guiding our project.

The assiduous help presumed by our guide Mr. M J Sampath Kumar and our co-guide

Mr. S B Rudraswamy was an inevitable part of the successful consummation of our project.

We also thank all other seen as well as unseen members who made us available all the

hardware resources as well as other inevitable help for the successful completion of the

project.

We are also grateful to Mr. Yatisha L for giving his precious and valuable suggestions.

-Anup Ratnakar Raikar

-Manjunath K.

-Manoj Naik P.

-Mayur K.

2

Abstract

„Robotics‟-the word has a deep meaning. Robotics in turn takes the scale of development by

employing various branches, tools, and mechanisms and performs a wide variety of functions

for the benefit of mankind. From this whole ocean of robotics, we have intended to build a

basic robot-„Spy Robot‟.

Being the students of 6th

sem Electronics & Communication branch, the concept that emerged

in our mind was to develop a Robot that can be controlled using Radio Frequency, where in

the robot a video transmission module has been integrated, which sends real time video

signals. Many time soldiers need to venture into the enemy canopy just to track their

activities, which is often a very risky job. Such dangerous job could be done using small a

spy robot.

The project is comprised of basically three modules, which handles all the basic

functionalities of the robot. The modules which we have integrated in this project are:

1. The controller part

2. Robot

3. Video transmitter, receiver and the display unit

Developed by:

-Anup Ratnakar Raikar

-Manjunath K.

-Manoj Naik P.

-Mayur K.

3

JSS MAHAVIDYAPEETHA

S. J. COLLEGE OF ENGINEERING. (An Autonomous Institution)

Department of Electronics & communication

SJCE, Mysore-570 006

CERTIFICATE

This is to certify that the project report entitled ‘Spy Robot’ is prepared by

Anup Ratnakar Raikar (USN No: 4JC08EC017)

Manjunath K (USN No: 4JC08ECO51)

Manoj Naik P (USN No: 4JC08ECO53)

Mayur K (USN No: 4JC08EC054)

Students of 6thsem Electronics and Communication branch have

satisfactorily completed their work.

___________________ ___________________

Signature of Guide Signature of Co-Guide

4

LIST OF CONTENTS Page No.

Chapter 1: Introduction 6

1.1: Description of Project 7

1.2: Goals of Project 7

1.3: User requirements 7

Chapter 2: Analysis and Implementation 8

2.1: Decomposition of problem 9

2.2: Technology used 9

2.3: Proposed solution 11

2.4: Hardware components used 14

And their description

2.5: Circuit diagrams and their description 16

Chapter 3: Programming of Microcontroller 20

3.1: Flowchart 22

3.2: Source code 26

Chapter 4: Future developments and Applications 32

4.1: Applications 33

4.2: What new can be added?? 33

Chapter 5: Conclusion and references 34

5.1: Problems we faced 35

5.2: Inference 35

5.3: References 35

5

LIST OF FIGURES Page No.

Fig 2.1.1: Decomposition of problem 9

Fig 2.3.1: Block diagram of the robot part 12

Fig 2.3.2: Block diagram of the controller part 13

Fig 2.5.1: DTMF encoder circuit 16

Fig 2.5.2: DTMF decoder circuit diagram 17

Fig 2.5.3: FM transmitter circuit diagram 17

Fig 2.5.4: FM receiver circuit diagram 18

Fig 2.5.5: Motor driving connections using L293D 19

Fig 4.1.1: Spy robot 33

LIST OF TABLES Page No.

Table 2.2.1: Tones and assignments in a DTMF system 10

Table 2.5.1: Operations performed 19

Table 3.1.1: Actions performed by the microcontroller 21

corresponding to the keys pressed

6

CHAPTER 1

INTRODUCTION

7

1.1 Description of Project

Robot- an electromechanical device automates the work in many applications like

military application, industrial power plant etc. Robots are reliable means to bring objects, do

settings etc at places where human interventions is rather impossible or can cause hazardous

effect on human health i.e, at nuclear power plants, chemical factories etc.

Spy robot is a RF controlled robot. A camera mounted on the robot sends real time

video signals on to the user side, which can be seen on a display. Robot movements can be

monitored looking at the display.

1.2 Goals of Project

Wireless control mechanism

Real time video streaming

1.3 User requirements

Looking at the present scenario, we have proposed the idea of building robot that

Can be controlled by a controller from remote place based on the video sent from

robot

Should be a non-autonomous robot

Robot should be made from the basic cost effective materials like wireless TV

camera, Microcontroller, etc..

8

CHAPTER 2

ANALYSIS AND

IMPLEMENTATION

9

2.1 Decomposition of Problem

Fig 2.1.1: Decomposition of Problem

2.2 Technology used

DTMF (Dual Tone Multi-Frequency):

In this project, robot movements are controlled by the keypad. In the course, when

any button is pressed, tone corresponding to the button pressed will be received at the

receiver part. This received tone is called Dual Tone Multi-Frequency (DTMF) tone. The

received tone is processed by microcontroller AtMega16 with the help of DTMF decoder

CM8870. The decoder decodes the DTMF tone into its equivalent binary number and this

binary number is sent to the microcontroller. The microcontroller is programmed to take a

decision for any given input and outputs its decision to the motor driver in order to drive the

motors to control the movement of robot and the camera mounted on the robot.

DTMF assigns a specific frequency (consisting of two separate tones) to each key so

that it can easily be identified by the electronic circuit. The signal generated by the DTMF

encoder is a direct algebraic summation, in real time, of the amplitudes of two sine (cosine)

waves of different frequencies, i.e., pressing ‘5’ will send a tone made by adding 1336 Hz

and 770 Hz to the other end of the line. The tones and assignments in a DTMF system are

shown in Table.

Display

Unit

Robot Display

Unit

FM receiver

+

DTMF decoder

Stepper motor

control

10

Table 2.2.1: Tones and assignments in a DTMF system

Frequency Modulation:

The FM band covers 88-108 MHz. There are signals from many radio transmitters in

this band inducing signal voltages in the aerial. The RF amplifier selects and amplifies the

desired station from the many. It is adjustable so that the selection frequency can be altered.

This is called tuning.

FM is used in radio broadcasting, for the transmission of the sound signal in standard

(NTSC)TV, for private land-mobile radio systems, for direct-satellite broadcasting, and for

cordless and cellular telephone systems etc.

Frequency Demodulation:

The FM receiver is designed using the popular Sony chip CXA1619BS used for

AM/FM receiver circuits. The chip is a 30 pin dual-in–line package with the following

functional blocks

Front-end block (RF amplifier, mixer , oscillator)

IF stage

FM discriminator

AF Power amplifier

The signal from the antenna is fed to IC CXA1619BS, which suppresses adjacent

channels and allows only the selected high frequency signal.

11

2.3 Proposed solution

The system consists of three basic blocks, each performing important functions. They are

1. Robot

2. Display unit and

3. Controller.

Robot:

It consists chassis with mechanical components similar to normal car on which a

camera is placed to gather visual information about its surroundings.

It has the following sub-blocks with specific functions:

Antenna: It receives the control signals (FM modulated) transmitted from the

controller and gives it to the FM receiver.

FM Receiver: It receives the FM modulated control signals and demodulates it to

produce DTMF signals.

DTMF decoder: The DTMF signals from the FM receiver are decoded in this DTMF

decoder to produce digital control signals which is used by the microcontroller to

control the motion of the robot.

Microcontroller: It uses control signals from the DTMF decoder to generate signals to

drive the motors.

Driver IC: As the signal strength from the microcontroller is not enough to drive the

motor, microcontroller drives the motor with the help of the driver IC from optimum

current levels.

Motors: They are driven by the driver IC, is connected to the wheels for motion.

Camera and Video Transmission Module: It produces video signals which are given

to the video transmission module which transmits the video signals.

Power supply: A 12V DC rechargeable battery is used for all the components of the

robot.

12

Fig 2.3.1: Block diagram of the robot part

Display unit:

It consists of PC, interfacing module, receiver module for video reception, power

supply and an antenna. Video signals from the robot are received at the receiver module and

is given to the PC for display through the interfacing module which most of the times consists

of TV tuner card.

Controller:

It essentially consists of a keypad, a power supply, a DTMF encoder, a FM

transmitter and an antenna. Keypad consists of keys for controlling the robot’s movement.

Depending on the key pressed, the DTMF encoder generates DTMF signals which are

modulated by the FM transmitter at a frequency of 100 MHz and transmitted using an

antenna.

13

Fig 2.3.2: Block diagram of the controller part

14

2.4 Hardware components used and their description

1. AtMega16:

The ATmega16 is a low-power CMOS 8-bit microcontroller based on the AVR

enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the

ATmega16 achieves throughputs approaching 1 MIPS per MHz allowing the system designer

to optimize power consumption versus processing speed.

Features:

Operating voltages: 4.5 to 5.5 V

High endurance and non-volatile memory segments

16kB of In-System self-programmable flash program memory

512 bytes EEPROM

1kB internal SRAM

Write/Erase cycles: 10,000 flash/100,000 EEPROM

Data retention: 20 years at 85°C/100 years at 25°C

2. L293D:

The L293D is designed to provide bidirectional drive currents of up to 600-mA at

voltages from 4.5 V to 36 V.

Features:

Wide Supply-Voltage Range: 4.5 V to 36 V

Output current 600 mA

Peak output current 1.2 A per channel

3. CM8870:

The CM8870 is a full DTMF receiver that integrates both bandsplit filter and decoder

functions into a single 18-pin DIP package. The CM8870 decoder uses a digital counting

technique to determine the frequencies of the limited tones and to verify that these tones

correspond to standard DTMF frequencies.

Features:

Low power consumption

15

Inexpensive 3.8 MHz time base

Single 5 V power supply

Supply voltage: 6 V max

Current on any pin: 10 mA max

4. UM91214B/ UM91215B:

The UM91215 is a single chip, silicon gate, CMOS integrated circuit with an on-chip

oscillator for a 3.58 MHz crystal or ceramic resonator. It provides dialing pulse or dual tone

multi-frequency dialing.

Features:

Wide operating voltage range: 2 V to 5.5 V

Key-in beep tone output

Uses inexpensive ceramic resonator (3.8 MHz)

5. CXA1619BS:

CXA1619BS is a one-chip FM/AM radio IC designed for radio-cassette tape

recorders and headphone tape recorders.

Features:

Low current consumption (Vcc: 3 V)

For FM, ID: 5.8 mA (typically)

Supply voltage: 14 V max

6. Radio AV Receiver and Camera:

These two components were used for the purpose of video transmission and reception.

A monitor is used to display the received signals.

Features:

Wireless transmission and reception

Small size

Light weight

Low power consumption

High sensitivity

Easy installation

Easy to concea

16

2.5 Circuit diagrams

DTMF encoder:

+5V

3.2V

C1

C2

C3

R1

R2

R3

R4

TONE O/P

GND

Fig 2.5.1: DTMF encoder circuit

Circuit description:

The figure above shows the circuit diagram of the DTMF encoder which resembles

the telephone set. It uses DTMF encoder integrated circuit, Chip UM 91215B. This IC

produces DTMF signals. It contains four row frequencies & three column frequencies. The

pins of IC 91215B from 12 to 14 produces high frequency column group and pins from 15 to

18 produces the low frequency row group. By pressing any key in the keyboard

corresponding DTMF signal is available in its output pin at pin no.7. For producing the

appropriate signals it is necessary that a crystal oscillator of 3.58MHz is connected across its

pins 3 & 4 so that it makes a part of its internal oscillator.

By pressing the number 5 in the key pad the output tone is produced which is the

resultant of addition of two frequencies, at pin no. 13 & pin no.16 of the IC and respective

tone which represents number '5' in key pad is produced at pin no.7 of the IC .

6

1 U 12

2 M 13

9 14

3 1 15

2 16

4 1 17

5 18

B 7

5

XTA

L

3.8

MH

z

6

1 U 12

2 M 13

9 14

3 1 15

2 16

4 1 17

5 18

B 7

5

1 2 3

4 5 6

7 8 9

* 0 # *

17

DTMF decoder:

Fig 2.5.2: DTMF decoder circuit diagram

Circuit description:

Detecting DTMF tones requires the capability to detect and differentiate between the

8 DTMF frequencies. It is also important to have a technique of detecting and rejecting false

tones caused by noise (e.g., speech). The input fed at pin2 is compared for the frequencies

corresponding to the key pressed. Equivalent code for the key pressed is obtained from the

pins 11, 12, 13, 14.

FM transmitter:

Fig 2.5.3: FM transmitter circuit diagram

i/p

18

Circuit description:

This wireless microphone circuit uses only a single transistor, with few additional

passive components. This FM transmitter is very compact and need only a single cell 1.5Volt

battery. The transmission range could be between 30-50m radius in open air, and practically

depends on the surrounding transmission path and obstacles.

FM receiver:

Fig 2.5.4: FM receiver circuit diagram

Circuit description:

The signal from band pass filter is fed to FM RF IN pin 13 of the IC. The tuning of

the signal is done by selecting the RF frequency and the local oscillator frequency with the

help of L2-C2 and L3-C3 tank circuit respectively. Fine tuning is done through ganged

capacitors. The heterodyning is done in the FM FE block which generates the IF signal of

10.7 MHz. The signal through FM IF (pin 18) is now sent to the FM IF block inside the

chip .This is done only after it is passed through a 10.7 MHz Ceramic filter (CF2).

The FM IF selects and amplifies the IF signal and generates the AF signal using the

FM discriminator block .The output of the IF block is the audio signal that is delivered to

pin 22 and then to pin 25 (AF IN) through a coupling capacitor. The FM discriminator is

tuned to 10.7 MHz using the ceramic/crystal resonator (CF3). The AF signal (demodulated

output from IF block using the FM discriminator) is further amplified (to drive the ear

phones) by the AF power amplifier. The volume at the output (ear phone) is controlled by

using a variable resistor (potentiometer) of maximum 50kOhm resistor RV1.The audio

signal is then fed to earphone through pin 28 and capacitor C21.

19

L293D driver connections:

Fig 2.5.5: Motor driving connections using L293D

Table 2.5.1: Operations performed

Left Motor Right Motor Robot Movement

Forward

Forward

Backward

Backward

Forward

Reverse

Forward

Backward

Forward

Right

Left

Backward

20

CHAPTER 3

PROGRAMMING OF

MICROCONTROLLER

21

Table 3.1.1: Actions performed corresponding to the keys pressed

a

Number

Pressed

Output of

DTMF Decoder

Input to the

Microcontroller

Output of

Microcontroller

Action

Performed

1 0x01

00000001

0x02

00000010

0x03

00000011

0x04

00000100

0x05

00000101

0x06

00000110

0x07

00000111

0x08

00001000

0x09

00001001

0x0A

00001010

0x0B

00001011

0x0C

00001100

PORTB=

0b00001111

Lights ON

0x01

00000001

2 0x02

00000010

0x02

00000010

PORTC=

0b00000101

Forward

3

4

5

6

7

8

9

*

0

#

0x03

00000011

0x04

00000100

0x05

00000101

0x06

00000110

0x07

00000111

0x08

00001000

0x09

00001001

0x0A

00001010

0x0B

00001011

0x0C

00001100

0x03

00000011

0x04

00000100

0x05

00000101

0x06

00000110

0x07

00000111

0x08

00001000

0x09

00001001

0x0A

00001010

0x0B

00001011

0x0C

00001100

PORTC=

0b00001001

PORTB=

0b00000000

PORTC=

0b00000110

PORTB=

0b00000000

PORTC=

0b00001010

-

PORTC=

0b00000000

Camera Up

Left

Halt

Right

Lights OFF

Backward

Camera Down

Retrace

Future use

System Stop

1

22

3.1: Flowchart:

Start

Configure input and

output ports

Read

PORTD

Is

PORTD=

?

LEDs ON Back PORTD=1

PORTD=2

Move Forward Save

Is

Camangle <

max value

?

PORTD=3

yes Move Camera

Up

Back

back

no

Next1

23

Is

Camangle >

min value

?

Next1

Move Backward Save PORTD=4

Wheels stop

rotating Save

PORTD=5

Move Right Save PORTD=6

LEDs OFF Back PORTD=7

Move Backward Save PORTD=8

PORTD=9

Move Camera

Down

Back

Next2

yes

no

24

Is

Counter =

final value

?

yes

no

Next2

Read the

reverse code

Rotate wheels

Increment

counter

Clear the code from

memory

Back

Do nothing Back

PORTD=*

PORTD=0

Stop the

wheels

PORTD=#

Is

Camangle =

0

?

no

Back

Next2

Next3

Back

Back1

yes

25

Next3

Is

Camangle >

0

?

Move camera

down

yes

Move camera

up

no

Back1

Save

Save the reverse

code

Delete the first

wheel status

Back

Generate the

reverse code for

the present code

26

3.2: Source code

#include <avr/io.h>

#define F_CPU 1000000

#include <util/delay.h>

int main()

{ intA[60]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

int i, count, flag, temp;

int stpr[8]={1,3,2,66,64,192,128};

int stprcount;

int camangle;

DDRA= 0xff;

DDRB= 0xff;

DDRC= 0xff;

DDRD= 0x00;

PORTA= 0x00;

PORTB= 0x00;

PORTC= 0x00;

PORTD= 0xff;

count= 0;

flag= 0;

temp= 0;

27

stprcount= 0;

camangle= 0;

while(1)

{

switch(PIND)

{

case 64:

case 79: PORTC=5; //0b00000101; forward key 2

temp=10;

flag=1;break;

case 16:

case 31: PORTC=10; //0b00001010; backward key 8

temp=5;

flag=1;break;

case 32:

case 47: PORTC=9; //0b00001001; left key 4

temp=6;

flag=1;break;

case 96:

case 111: PORTC=6; //0b00000110; right key 6

temp=9;

flag=1;break;

28

case 160:

case 175: PORTC=0; //0b00000000; stop key 5

temp=0;

flag=1;break;

case 128:

case 143: PORTB=15; //0b00001111; LED ON key 1

flag=0;break;

case 224:

case 239: PORTB=0; //0b00000000; LED OFF key 7

flag=0;break;

case 192:

case 207: flag=0;

if(camangle<100) // Camara up key 3

{

PORTA=stpr[stprcount];

stprcount=stprcount+1;

_delay_ms(100);

camangle=camangle+1;

if(stprcount==8)

stprcount=0;

} break;

29

case 144:

case 159: flag=0;

if(camangle>-100) // Camara down key 9

{

PORTA=stpr[stprcount];

stprcount=stprcount-1;

_delay_ms(100);

camangle=camangle-1;

if(stprcount==-1)

stprcount=7;

}

break;

case 48:

case 63: PORTC=0; //0b00000000; Stop and Reset key 12

while(camangle!=0)

{

if(camangle<0)

{

camangle=camangle+1;

PORTA=stpr[stprcount];

stprcount=stprcount+1;

_delay_ms(100);

30

if(stprcount==8)

stprcount=0;

}

else

if(camangle>0)

{

camangle=camangle-1;

PORTA=stpr[stprcount];

stprcount=stprcount-1;

_delay_ms(100);

if(stprcount==-1)

stprcount=7;

}

} break;

case 80:

case 95: flag=0; // Retrace path key 10

for (i=0;i<60;i++)

{ PORTC= A[i];

_delay_ms(500);

A[i]= 0;

PORTC= 0;

_delay_ms(50);

31

} break;

default: PORTB= 0; //0b00000000; Do nothing

PORTC= 0;

flag= 0; break;

}

// Codes to store path trail

If (flag==1)

{ flag= 0;

_delay_ms(1);

count= count+1;

if (count==500)

{ count=0;

for(i=59;i>0;i--)

{A[i]=A[i-1];

}

A[0]=temp;

}

}

}

}

32

CHAPTER 4

FUTURE DEVELOPMENTS AND

APPLICATIONS

33

And finally….!!

Fig 4.1.1.: Spy robot

4.1: Applications

It can be used in spying purposes to get the confidential details of anybody from

remote area without making our life in danger.

The camera which has been installed can provide the live streaming of the places

where a human can’t reach (especially during natural calamities like earthquake).

It can be also used by our defense agency in many cases.

Wireless security and surveillance in hot spots

Search and rescue operation

Manoeuvring in hazardous environment

Caves exploration

34

4.2: What new can be added..??

GPS technology can be integrated

Image/ Video capture option

Locomotion of the robot on other terrains

360 degree rotation of the camera so that we can get complete view of the robot’s

environment

Voice controlled locomotion of robot instead of button control

(Key ‘0’ is reserved for the purpose of future use)

CHAPTER 5

35

CONCLUSION AND

REFERENCES

5.1: Problems we faced…..

Stepper motor interfacing

We thought of including angular rotation for the camera and enabling a focus of

about 180 degrees. Fortunately, we were able to write the source code for about 90

degree movements (algorithm similar to stepper motor programming using

microprocessor 8086).

Enabling all the PORTC pins of AtMega16

We were able to rectify this problem with the help of internet sources.

36

FM reception

Because of this we were not able to properly decode the received signals. So our

idea was to use a preset at the FM transmitter module. Our idea worked fairly well!!

Retrace program

We thought of including about 10 seconds retrace option in our program.

Present path details were stored in the flash memory of AtMega16 (similar to the

stack operation). Soon after calling the retrace option, path status was popped off the

stack.

5.2: Inference

The Robotics- the word has a deep meaning. Robotics in turn takes the scale of

development by employing various branches, tools, mechanism and performs a wide variety

of functions for the benefit of mankind. From this whole ocean of robotics, we have finally

built a basic robot- “Spy Robot” quite successfully.

But still this is not the end… It’s the beginning of the new era of robotics. Still we

have a long way to traverse in which we further decide to extend our robotic art to work out

for a specific application as well as increase its functionalities by proper deployment of

sensors and developing new architectures and designs even more accurately. Even this can

be extended to control the robot from the internet as well as by making an appropriate mobile

application too, even with lesser cost.

Thus the scope of further expansion of this project – “Spy Robot” is endless.

5.3: References

www.avrfreaks.com

www.wikipedia.org

www.alldatasheets.com

Google web search