A Need to be Free

Kinect and custom-built fabric interface, Processing, and Symbolic Sound's Kyma

This piece began as an exploration in instrument interface design for the Kinect, a motion sensing input device for the Xbox entertainment system. Unsatisfied with the invisible nature of the Kinect interface on its own, I wanted to make something more tactile and physically responsive. The resulting flexible fabric screen brought a sense of restraint and confinement. The sounds produced by the performer’s actions of stretching and prodding the fabric interface embody this feeling, a need to be free.

I created a Processing program utilizing a modified software library developed for interpreting the proprietary formatted messages from the Kinect. This analyzes designated ranges of the Kinect’s visual field corresponding to the space occupied by the fabric.

A blob-detection algorithm in the Processing program analyzes for the x-, y-, and z-axis as well as the width and height of the first two blobs detected which breach a threshold of the z-axis of the visual field.A separate algorithm calculates the average three-dimensional position of any space breaching the z-axis threshold.

Data streams produced by this analysis are scaled and output as OSC messages via ethernet to Kyma where they are further scaled and mapped to appropriate ranges to effect musical parameters.