Making grains tangible: microtouch for microsound

TL;DR

This paper introduces microtouch, a novel tactile interface for granular synthesis that provides real-time, multidimensional physical feedback corresponding to sonic grains, enhancing tangible interaction with digital sound.

Contribution

It proposes a new force pulse-based approach for tactile display of granular synthesis, filling a gap in tangible musical interfaces with real-time, multidimensional feedback.

Findings

Force pulse approach enables perceivable multidimensional tactile feedback.

Real-time tactile display aligns with sonic grain generation timescale.

Initial psychophysics experiment shows potential for tangible manipulation of grains.

Abstract

This paper proposes a new research direction for the large family of instrumental musical interfaces where sound is generated using digital granular synthesis, and where interaction and control involve the (fine) operation of stiff, flat contact surfaces. First, within a historical context, a general absence of, and clear need for, tangible output that is dynamically instantiated by the grain-generating process itself is identified. Second, to fill this gap, a concrete general approach is proposed based on the careful construction of non-vibratory and vibratory force pulses, in a one-to-one relationship with sonic grains. An informal pilot psychophysics experiment initiating the approach was conducted, which took into account the two main cases for applying forces to the human skin: perpendicular, and lateral. Initial results indicate that the force pulse approach can enable perceivably multidimensional, tangible display of the ongoing grain-generating process. Moreover, it was found that this can be made to meaningfully happen (in real time) in the same timescale of basic sonic grain generation. This is not a trivial property, and provides an important and positive fundament for further developing this type of enhanced display. It also leads to the exciting prospect of making arbitrary sonic grains actual physical manipulanda.