The MIDI format has long been used to create some banging electronic music, so it’s refreshing to see how [John P. Miller] applied the standard in his decidedly analog self-playing robotic xylophone.
Framed inside a fetching Red Oak enclosure, the 25-key instrument uses individual solenoids for each key, meaning that it has no problem striking multiple bars simultaneously. This extra fidelity really helps in reproducing the familiar melodies via the MIDI format. The tracks themselves can be loaded onto the device via SD card, and selected for playback with character LCD and rotary knob.
The software transposes the full MIDI music spectrum of a particular track into a 25-note version compatible with the xylophone. Considering that a piano typically has 88 keys, some musical concessions are needed to produce a recognizable playback, but overall it’s an enjoyable musical experience.
Perhaps most remarkable about this project is the documentation. If you want to build your own, everything you need to know is available online, and the no-solder approach makes this project very accessible. Most of the write-up happened some years ago, and we’re really interested to see what improvements have been made since.
The robotic xylophone is reminiscent of these automatic tubular bells from some time ago. These musical hacks can be particularly inspiring, and we can’t wait to see more.
[Thanks Assad Ebrahim for the great tip.]
Too bad the clacking of the solenoids or wood on wood hitting takes away from the xylophone sound. Maybe some other solenoids or dampers would help. Otherwise cool build
This.
The solenoid noise detracts greatly from the music. We need a standard silent solenoid hack for these projects.
2 kg solenoids aren’t the best choice when you need 10 g of force.
In my Robot Glockenspiel I replace solenoids with 8 servos. It eliminated the clicking noises however introduced some light buzzing sounds from the servos.
https://www.youtube.com/watch?v=69pGYTYSEug
wow!
Cool project and it’s actually enjoyable to listen to. The sound bars are metal which would make this a glockenspiel not a xylophone. The literal translation of xylophone is wood sound, xylophones have wooden sound bars.
Having just put in a piano playing system and have another one in waiting. I can say it’s impossible to get silence out of solenoids. However the best design uses push when energized, not pull. It strikes from below, with gravity not springs for return. Also in any silent mechanism there can be no slop in linkages and bearings. Traditionally woven felt called bushing cloth lines each bearing point. The mallet shanks are too heavy.
Cool build, I like the tune selection (plus the large array of available tunes) the humble looks of an old music box and the ability of volume control.