Knock pattern based door lock with smart phone application

Current digital door locks have a risk of being broken because they are exposed outside and damaged by the electric shock. In order to increase safety, this work proposes an unexposed door lock, which removes the keypad in the outside. Instead of the keypad, it recognizes knock pattern. Users can setup the password using the knock pattern, and by knocking the same pattern, the door is open. The door lock can communicate with the smart phone application, also. Users can open the door by inputting the knock pattern to the smart phone, and it further increases safety because it removes the knocking sound and the possibility of being overheard.