DTMF Cell Phone Based Door Opener
The main objective of this project is to unlock a garage door by a mobile phone using a unique password entered through the keypad of the phone. Opening and closing of garage doors involves human labor. In this proposed system, the opening and closing of a garage door is achieved by using a mobile phone. The owner can call to a mobile phone interfaced to the system which in turn is connected to the garage door that can open/close the door by entering the password. This method is very convenient as one doesn’t have to get down of his car to open/close the door physically.
This project is based on the concept of DTMF (dual tone multi – frequency). Every numeric button on the keypad of a mobile phone generates a unique frequency when pressed. These frequencies are decoded by the DTMF decoder IC at the receiving end which is fed to the microcontroller. If this decoded values (password entered by the user) matches with the password stored in the microcontroller, then the microcontroller initiates a mechanism to open the door through a motor driver interface.
Further this project can be incorporated with an EEPROM i.e., a non-volatile memory so that the password can be changed by the owner.