Seminar Topics & Project Ideas On Computer Science Electronics Electrical Mechanical Engineering Civil MBA Medicine Nursing Science Physics Mathematics Chemistry ppt pdf doc presentation downloads and Abstract

DTMF based Mobile Controlled Robot

[attachment=22076]

INTRODUCTION:
THE robot, integrated with a mobile phone, forms the crux of this project. This integrated architeture is controlled by a supplementary mobile phone, which initiates the call. Once the call is associated, any button pressed corresponds to a unique tone at the other end. The tone is termed as ‘Dual Tone Multiple Frequency’ (DTMF ) , which is perceived by the robot with the help of a cellular phone stacked in it. The received tone is fed into the DTMF decoder (CM8870), which decodes the DTMF tone into its equivalent binary. Binary output from the decoder is consequently administered by the microcontroller (P89V51RD2). 89V51RD2 is pre- programmed to take necessary decisions corresponding to the given set of binary inputs. Output from P89V51RD2 is provided to the drivers L293D and ULN2003. The former of which acts as a regulator to drive the DC motor while; the latter can be provided to drive the electrical appliances.
Cellular phone generating the call acts as a remote control obviating the need for construction of superfluous receiver and transmitter units and thus can be used for tele-control of electronic appliances.

WORKING :

As shown in the above block diagram, the first block is the cell phone. So, it acts as any DTMF generator with tone depending upon key pressed. DTMF decoder IC ,i.e., MT8870 decodes the received tones & gives binary equivalent of it to the microcontroller. The Microcontroller is programmed such that appropriate output given to the motor driver IC L293D which will drive the two DC Motors connected to it. The concept used for driving is “Differential Driver”. So ultimately the motors rotate according to the key pressed on the keypad of the cell phone.


In order to control the robot, you have to make a call to the cellphone attached to the robot from any phone.
now the phone is picked by the phone on the robot through autoanswer mode(which is in the phn, just enable it).
now when you press 2 the robot will move forward
when you press 4 the robot will move left
when you press 8 the robot will move backwards
when you press 6 the robot will move right
when you press 5 the robot will stop.



APPLICATION :

• Scientific.
• Military and law Enforcement.
• Search and Rescue.
• Recreation and Hobby.

FURTHER IMPROVEMENTS AND FUTURE SCOPE :
• IR Sensors.
• Password Protection.
• Alarm Phone Dialer.
• Adding a Camera

to get information about the topic " DTMF based Mobile controlled robot" full report ppt and related topic refer the link bellow

https://seminarproject.net/Thread-mobile...technology

https://seminarproject.net/Thread-dtmf-b...lled-robot

http://seminarprojectsshowthread.php?tid=29304&google_seo=cnCb++&pid=63774#pid63774

https://seminarproject.net/Thread-dtmf-b...ot-project

https://seminarproject.net/Thread-mobile...pplication

Mobile controlled DTMF ROBOT

[attachment=29819]

Introduction

What is a Mobile controlled DTMF ROBOT?

DTMF Mobile ROBO is a machine that can be controlled with a mobile . 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 on the robot. The received tone is processed by the microcontroller with the help of DTMF decoder. The microcontroller then transmits the signal to the motor driver ICs to operate the motors & our robot starts moving

Why build a DTMF ROBOT?

Conventionally, Wireless-controlled robots use rf circuits, which have the drawbacks of limited working range, limited frequency range and the limited control. Use of a mobile phone for robotic control can overcome these limitations. It provides the advantage of robust control, working range as large as the coverage area of the service provider, no interference with other controllers and up to twelve controlles.
Although the appearance and the capabilities of robots vary vastly, all robots share the feature of a mechanical, movable structure under some form of control. The Control of robot involves three distinct phases: perception, processing and action. Generally, the preceptors are sensors mounted on the robot , processing is done by the on-board microcontroller or processor, and the task is perfomed using motors or with some other actuators.

DTMF Decoder

The MT-8870 is a DTMF Receiver that integrates both band split filter and decoder functions into a single 18-pin DIP or SOIC package. It is manufactured using CMOS process technology. The MT-8870 offers low power consumption (35 mW max) and precise data handling.

Pin configuration of MT-8870

Its filter section uses switched capacitor technology for both the high and low group filters and for dial tone rejection. Its decoder uses digital counting techniques
to detect and decode all 16 DTMF tone pairs into a 4-bit code. External component count is minimized by provision of an on-chip differential input amplifier, clock generator, and latched tri-state interface bus. Minimal external components required includes a low-cost 3.579545 MHz color burst crystal, a timing resistor, and a timing capacitor.
The filter section is used for separation of the low-group and high group tones andit is achieved by applying the DTMF signal to the inputs of two sixth order switchedcapacitor band pass filters, the bandwidths of which corresponds to the low and high
group frequencies. The filter section also incorporates notches at 350 and 440 Hz forexceptional dial tone rejection. Each filter output is followed by a single orderswitched capacitor filter section which smoothes the signals prior to limiting. Limiting
is performed by high-gain comparators which are provided with hysteresis to preventdetection of unwanted low-level signals. The outputs of the comparators provide full
rail logic swings at the frequencies of the incoming DTMF signals.Following the filter section is a decoder employing digital counting techniques todetermine the frequencies of the incoming tones and to verify that they correspond tothe standard DTMF frequencies.

POWER SUPPLY UNIT (+5V)

Power supplies are designed to convert high voltage AC mains electricity to a suitable low voltage supply for electronics circuits and other devices. A power supply can by broken down into a series of blocks, each of which performs a particular function.

RECTIFIER:

A bridge rectifier can be made using four individual diodes, but it is also available in special packages containing the four diodes required. It is called a full-wave rectifier because it uses all the AC wave (both positive and negative sections). 1.4V is used up in the bridge rectifier because each diode uses 0.7V when conducting and there are always two diodes conducting, as shown in the diagram below. Bridge rectifiers are rated by the maximum current they can pass and the maximum reverse voltage they can withstand (this must be at least three times the supply RMS voltage so the rectifier can withstand the peak voltages). Please see the DIODES page for more details, including pictures of bridge rectifiers. In this alternate pairs of diodes conduct, changing over the connections so the alternating directions of AC are converted to the one direction of DC.

SMOOTHING:

Smoothing is performed by a large value electrolytic capacitor connected across the DC supply to act as a reservoir, supplying current to the output when the varying DC voltage from the rectifier is falling. The diagram shows the unsmoothed varying DC (dotted line) and the smoothed DC (solid line). The capacitor charges quickly near the peak of the varying DC, and then discharges as it supplies current to the output.

i need some more information to work on this project
or introduce sites for searching
thanks alot