A Project Synopsis

On

Spy-Bot

in partial fulfillment for the award of the degree

of

B. Tech. in Electronics and Communication

Submitted to: Submitted By:

Arun Chopra Deepika Pareek (10EUDEC031)

Head of Department Alankar Anand (10EUDEC011)

Electronics and Communication Gifty G. Thomas(10EUDEC037)

EC A, 7th Sem

DEPARTMENT OF ELECTRONICS AND COMMUNICATION

JECRC UDML COLLEGE OF ENGINEERING

July 2013

SPY-BOT

Summary

In this project, the robot is controlled by a mobile phone that makes a call to the mobile phone attached to the robot. In

the course of a call, if any button is pressed, a tone corresponding to the button pressed is heard at the other end of the

call. This tone is called ‘dual-tone multiple-frequency’ (DTMF) tone.

The robot perceives this DTMF tone with the help of the phone stacked in the robot. The received tone is processed by

the ATmega16 microcontroller with the help of DTMF decoder MT8870.

The decoder decodes the DTMF tone into its equivalent binary digit and this binary number is sent to the

microcontroller. The microcontroller is pre-programmed to take a decision for any given input and outputs its decision

to motor drivers in order to drive the motors for forward or backward motion or a turn.

The mobile that makes a call to the mobile phone stacked in the robot acts as a remote. So this simple robotic project

does not require the construction of receiver and transmitter units.

DTMF signalling is used for telephone signalling over the line in the voice-frequency band to the call switching

centre. The version of DTMF used for telephone tone dialling is known as Touch-Tone.

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.

Technical Details

This project can be sub divided into 3 parts

1. The input (DTMF decoder IC-CM8870)

2. Controller (atmega8 microcontroller)

3. Output (The motor driver IC and motors)

1. Input: (DTMF decoder circuit)

When we press the digit 1 on the keypad, we generate the tones 1209 Hz and 697 Hz. Pressing the digit 2 will generate

the tones 1336 Hz and 697 Hz.

Sure, the tone 697 is the same for both digits, but it take two tones to make a digit and the decoding equipment knows

the difference between the 1209 Hz that would complete the digit 1, and a 1336 Hz that completes a digit 2.

Thus each key in the keypad gives different 4 bit binary number in the output (pin no 14, 13, 12, 11).This binary no is

processed by the microcontroller to give specific output to the motor.

2. Motor Driver:-L293D

L293D is a dual H-bridge motor driver integrated circuit (IC). The current from the microcontroller is only of the order

of 1µA which is not sufficient to drive the motors. Therefore motor drivers are used which act as current amplifiers

since they take a low-current control signal and provide a higher-current signal which is used to drive the motors.

3. Control with MCUs

The AtMega16 microcontroller used in this project has 16Kb of flash memory with 40 general purpose pins. These

input/output pins can be used to receive input from the DTMF Decoder as well as to send output signals to control the

motors. However the MCUs PORT outputs are not powerful enough to drive DC motors directly, we need some kind

of drivers to facilitate this. A very easy and safe is to use popular L293D ICs. It is a 16 PIN chip. The pin

configuration is as follows. This chip is designed to control 2 DC motors.

Origin of the proposal

The idea of controlling the robot was originated when we realised that when someone calls the customer care number

from their cell phone. Later on, when we studied the tone-based command system in an engineering subject, the

concept of remote control through tones was very much clear.

This led to the conclusion that any mechanical device can be operated to move through the cell phone.

Definition of the problem

The robot is in form of a vehicle mounted with a web cam, which acquires and sends video to a 3G mobile phone or

PC. We can’t forget 26/11 when people lost their lives and many people were injured in the worst terror attack seen in

country. Our idea is to make a robot to tackle the hostage situation & the worst conditions which cannot be handled by

human being. Humans are moved out from direct exposure to potentially dangerous situations. Robotic system can

perform many security and surveillance functions more effectively than humans. For instance, at one place it can be

used by bomb disposal squad, while at another instance it can be used for handling mines. While another application

can be to provided up to date information in hostage situation. The robot is made for purpose by military operation for

navigation in forest.

Objective

Main aim of our project is to study development of the 3G mobile operated robot which can be remotely controlled.

Here, we are showing the method of using the DTMF to operate robot because the robot is operated by mobile so the

range of robot communication is not limited.

Work Plan in stages

Stage 1: Literature review of the Project.

Stage 2: Procurement of Components.

Stage 3: Analysis of the circuit, Mounting, Assembling, Soldering of components, testing of bot.

Stage 4: Final testing, Preparation of Report, Publishing in Journals, magazines.

Utilization of the outcome of project

Scientific

Military and law enforcement

Search and rescue

Recreation and hobby