ECE 4760 Final Project

Music Lockbox


Shryan Appalaraju (

Shuhan Wang (



our project video


"In this project, we designed and built a lockbox in which the password is in music consisting of sounds of an acoustic guitar." -Soundbite

The user enters the music password using a keypad in which each key corresponds to a different note on an acoustic guitar.  We use the karplus strong algorithm to simulate the sound of a string being plucked.  The user must enter the password twice to save a password, and the then the solenoid lock will be activated to lock the safe.  The user can then attempt to unlock the safe by entering the correct password.  A password consists of the notes played, as well as the rhythm at which the notes are played.

We created this device because it greatly increases the complexity of a password given a series of buttons to press because knowing the combinations of buttons pressed is not enough information to unlock the safe; you must also know the rhythm of the password, specifically the timing between the keys that are pressed.  Additionally, we feel that with ability to make a tune as a password, it is easier for a user to remember a melody than just a series of numbers pressed.  Therefore, with just a keypad, we can increase the complexity of a password while keeping the same simplicity of a user just pressing keys to create it.