A conceptual framework for motion based music applications

Imaginary projections are the core of the framework for motion based music applications presented in this paper. Their design depends on the space covered by the motion tracking device, but also on the musical feature involved in the application. They can be considered a very powerful tool because they allow not only to project in the virtual environment the image of a traditional acoustic instrument, but also to express any spatially defined abstract concept. The system pipeline starts from the musical content and, through a geometrical interpretation, arrives to its projection in the physical space. Three case studies involving different motion tracking devices and different musical concepts will be analyzed. The three examined applications have been programmed and already tested by the authors. They aim respectively at musical expressive interaction (Disembodied Voices), tonal music knowledge (Harmonic Walk) and XX century music composition (Hand Composer).