DTMF CONTROLLED WIRELESS CAR WITH VIDEO FEEDBACKPresented by:- Aritra Roy (Roll No.-07)

Nirban Goswami (Roll No.-08)

Subir Rakshit (Roll No.-17)

Sourav Biswas (Roll No.-19)

Piu Das (Roll No.-51)

Laboni Ghosh (Roll No.-55)

E.C.E. , 4th Year.

Guru Nanak Institute of Technology

APROJECT

ON

Introduction

Radio control is the use of radio signals to remotely control a device. It is used frequently to refer to the control of model vehicles from a hand-held radio transmitter. Industrial, military, and scientific research organizations make use of radio-controlled vehicles as well.

A remote control vehicle is any mobile device, controlled by a means that does not restrict its motion with an origin external to the device. This is often a radio control device or an infrared controller. A remote control vehicle (RCV) differs from a robot in that the it is always controlled by a human and takes no positive action autonomously.

HISTORY OF WIRELESS VEHICLES

The First Remote Control Vehicle / Precision Guided Weapon is propeller-driven radio controlled boat, built by Nikola Tesla in 1898.

The next evolution involved the fitting of a bomb to a glider airframe the GB-4 having a TV camera to assist the controller with targeting. The third class of guided weapon was the remote controlled B-17. Germany also deployed a number of more advanced guided strike weapons like the V-1 or V-2.

Theory

BLOCK DIAGRAM

WHAT IS DTMF ???????? Dual-Tone Multi-Frequency (DTMF)

Dual-tone multi-frequency (DTMF) signaling is used for telecommunication signaling over analog telephone lines in the voice-frequency band between telephone handsets and other communicating devices and the switching center. It is known by the trademarked term Touch-Tone.

A DTMF Telephone Keypad

DTMF CONTINUING………… DTMF assigns a specific frequency (consisting of two separate

tones) to each key s that it can easily be identified by the electronic circuit. The signal generated by the DTMF encoder is the direct algebraic submission, 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 mobile.

WHY DTMF????

Conventionally, wireless-controlled robots use RF circuits, which have the drawbacks of limited working range, limited frequency range, limited control and low bandwidth.

Use of a mobile phone (DTMF) for robotic control can overcome these limitations. It provides the advantages of robust control, working range as large as the coverage area of the service provider, no interference with other controllers and up to twelve controls.

Hardware Design &

Implementation

OVERVIEW

Here two mobile phones are used for controlling the car, one mobile in our hand and the other stacked on the car. The phone in our hand is transmitter of DTMF tone and mobile situate at the car is receiver. At first we will make a dedicated link or connection between this two mobile by calling. Now we will control the car using DTMF signal.

Receiving the tones the receiver section passes it to the DTMF decoder IC (CM 8870). The decoder then decodes the tones and sends the data to the micro controller chip. The micro controller accordingly guides the L293D h-bridge motor driver IC. According to the instruction from the micro controller the motor driver operates two motors of the car.

WORKING OF DTMF DECODER

CIRCUIT DIAGRAM

Software Design &

Implementation

FLOW CHART

1. Keil µ-Vision:

ROLE IN THE DESIGN:

µVision Keil provides IDE for 8051 programming & is very easy to use. When starting a new project, simply select the microcontroller you use from the Device Database and the µVision IDE sets all Compiler, Assembler, Linker, and Memory options. It’s device database is large which supports many ICs of the 8051 family. A HEX file can be created with the help of Keil which is required for burning onto chip. It has a powerful debugging tool which detects most of the errors in the program.

2. Xeltek SuperPro 580U Universal Programmer:

To burn the .hex file of the program into the microcontroller chip (ATMEGA 16), we used the Xeltek SuperPro 580U Universal Programmer and Logic IC Tester kit.

Outcome

OUTPUT FROM DTMF DECODER

OUTPUT OF THE MICROCONTROLLER

No. PressedO/P of DTMF Decoder

(CM8870)O/P of The

MicrocontrollerAction Performed

2 0x02 (0000 0010) 0x89 (1000 1001) Forward Motion

4 0x04 (0000 0100) 0x85 (1000 0101) Turn Left

6 0x06 (0000 0110) 0x8A (1000 1010) Turn Right

8 0x08 (0000 1000) 0x86 (1000 0110) Backward Motion

5 0x05 (0000 0101) 0x00 (0000 0000) Stop/ Break

Application

1) Scientific Application

Remote control vehicles have various scientific uses including hazardous environments, working in the deep ocean, and space exploration.

2) Military and Law Enforcement

  Military usage of remotely controlled military vehicles dates back to the first half of 20th century. Soviet Red Army used remotely controlled Teletanks during 1930s in the Winter War and early stage of World War II.

3) Search and Rescue

UAVs will likely play an increased role in search and rescue in the United States. This was demonstrated by the successful use of UAVs during the 2008 hurricanes that struck Louisiana and Texas.

4) In Future Weapons

The modern day weapons and armored vehicles, planes and water vehicles are mostly designed using wireless control so that they cam sneak into the enemy areas and attack more furiously and perfectly.

5) Recreation and Hobby

There are many types of radio controlled vehicles. These include on-road cars, off-road trucks, boats, airplanes, and even helicopters. The "robots" now popular in television shows such as Robot Wars, are a recent extension of this hobby.

Further Improvements

1. IR Sensors:

  IR sensors can be used to automatically detect & avoid obstacles if the robot goes beyond line of sight. This avoids damage to the vehicle if we are maneuvering it from a distant place.

2. Password Protection:

  Project can be modified in order to password protect the robot so that it can be operated only if correct password is entered.

3. Alarm Phone Dialer:

  By replacing DTMF Decoder IC CM8870 by a 'DTMF Transceiver IC’ CM8880, DTMF tones can be generated from the robot. So, a project called 'Alarm Phone Dialer' can be built which will generate necessary alarms for something that is desired to be monitored .

CONCLUSION

Finally the we can conclude that the cell phone can be used more efficiently is designing a wireless car using DTMF control than its counterpart RF signal.

But  it was not at all easy to construct such a car which actually runs with the help of a CELL PHONE. Initially it was near to infeasible as we never knew about the DTMF working as to how and where the wires-input is to be connected, the connection of the head phone and many more. We had many such problems, but with the help of our faculty members and of course with the related information that we managed to collect from the internet.

Thank you