bauhausinteraction writes "A team from the Bauhaus-University and Native Instruments Developers built and programmed a fully functional interactive Lego Sequencer / Tangible Groove Machine that sends control data to the Maschine drum sequencer to make music. The thing was built within 24 hours as an unofficial weekend collaboration between bauhausinteraction and NI at the MidiHack 2014 in Stockholm. A standard webcam is mounted underneath the baseplate. The image is processed by a Python Script using the OpenCV Library to track the bricks. The tricky bit was to not track the user's hand, but we succeeded at that as well.
The information about brick color, position, and orientation is derived from the image and then converted into OpenSoundControl (OSC) messages. Those are sent over a network connection to a computer running Native Instruments Maschine to play back the sounds. Of course, this would work with other sound generators as well, since the whole thing simply spits out OSC-Messages and MIDI — but hey: if the guys from Native are there, you'd better use their Maschine stuff. Being real Masterbuilders, of course we used only unmodified, standard Lego Parts and no Kragle* for the construction. (*see the Lego Movie for reference.)"