November 9th, 2021—
The classic MP3 player was a truly innovative device for its time, however with the advent of modern smartphones and other do-it-all gadgets, they have largely fallen by the wayside. In order to add a new twist, Norbert Zare decided to implement an MP3 player that not only responds to user inputs by moving the volume knob and tilting some notes to signal the next track, but can also be controlled simply by waving a finger in front of it.
Gesture control was achieved using the PAJ7620U2 sensor, which can quickly detect movements within a 3D space and output its findings over the I2C bus to a host microcontroller. Zare set up his Arduino Uno’s program to continually check for a new gesture, and based on the one being read, perform a certain action. For example, making a clockwise circle with a single finger will increase the volume, turn the servo attached to the volume knob, and change the text on the attached LCD to match. Other functions include skipping tracks and resuming/pausing.
When a motion has been picked up by the Uno, it also sends a signal to an attached and partially disassembled MP3 player’s button pad that controls the actual music being played as well as its volume. You can read more about this project here on Hackaday.io and check out Zare’s video below.