DIY 3D Interface: Tic Tac Toe from Kyle McDonald on Vimeo.

The Theremin, not too far off from its one hundredth birthday (start planning now), was a breakthrough in enabling a touch-free gestural control in space. Using the same principle that allows the Theremin to sense hand position, Kyle McDonald has created a 3D interface, and posted the process on Instructables. CDM gave him some of the inspiration:

Your recent post, "Theremin as AV Controller", inspired me to finish an idea that’s been living in my sketchbook. It operates on the same capacitive sensing idea as the Theremin, but in 3D — using just an Arduino, aluminum foil, and six resistors. I’m planning on using it as an instrument, interfacing with a wave terrain synthesis system. In the meantime, I put together a demo video and an instructable so other people interested in alternative controllers can experiment with it. The code is in Arduino outputs coordinates via serial, and the example code is done in Processing, so it’s only minutes from interfacing with your audio/visual tool of choice.

In the spirit of sharing, Kyle says he’d be happy for people to improve on the design: “If you think you can build one that is simpler and equally accurate, or slightly more complex and more accurate, share in the comments!”

DIY 3D Controller @ Instructables: “Make a 3D interface using an six resistors, aluminum foil, and an Arduino. Take that, Wii.”

Here’s the original post, which came from our friend Sarah Angliss, who’s been using the Theremin as a controller for A/V sets in Max/MSP/Jitter:

Theremin as AV Controller: Technical Details from Spacedog

Updated: Kyle writes with some additional details on what he’s doing musically, and from where he draws some of his inspiration:

I developed this as part of a wave terrain synthesis system. First, you would initiate a virtual 3D space with a "pressure field", so if you traced a path through the space the result would be an audio signal. Imagine instantaneously freezing the air in a noisy room, and moving your ear through the room in various paths at the speed of sound. If you moved towards a sound source, you’d hear the sound like normal, if you moved away it’d be in reverse, assuming it is radiating omnidirectionally you could move in a circle around it and not hear the sound at all. Something like "aural bullet time"? The interface is for tracing, selecting, and modifying these paths. Separate gestures are used for looping the paths, controlling their rate, etc.

[1] http://www.lovid.org/synths/syncarmonica.htm
[2] http://www.turbulence.org/Works/arcangel/
[3] http://www.oskarfischinger.org/Sounding.htm
[4] http://www.seeingwithsound.com/
[5] http://ccrma.stanford.edu/~woony/software/sonart/
[6] http://webcenter.ru/~vsoft/BitmapPlayer.htm
[7] http://www.nicolasfournel.com/audiopaint.htm

Look forward to hearing comments from readers, or (especially) related ideas!