The Glockentar combines a glockenspiel with a guitar.
Each time a string is plucked a glockenspiel bell is struck with a solenoid, and a beam of light is projected across the length of the string.
The light follows a logarithmic curve in terms of it’s speed as it goes up and down the string. It starts fast, pauses for a moment then goes back down the string.
The lights are essentially rectangles made in openFrameworks, then sent to MadMapper via Syphon.
In MadMapper they are then mapped to the strings.
An Arduino is used to turn the strings into switches. Each string acts as a ground, and electricity is sent to the pick. When a string is plucked with the pick the switch is closed and the solenoids and projections are triggered.
Here is the Arduino code