Abstract: In this project, we present the controlling of a Robot using DTMF technique .The robot is controlled by a mobile phone that calls the other mobile phone attached to the robot. In the course of the call, if any button is pressed, the tone corresponding to the button pressed is heard at the other end. This tone is called “Dual Tone Multi Frequency tone (DTMF)”.Using DTMF code, direction of motion of the robot can be controlled by mobile phone. The above system can be used for military purpose as ‘bomb detector’ and as ‘spy robot’ and also for surveillance. 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 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 controls. 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 any button in DTMF will send a tone made by adding 1336 Hz and 770 Hz to the other end of the mobile.

Keywords: Dual Tone Multi Frequency tone (DTMF), Robot, Mobile Operated, Embedded System.