Consonance of Vibrotactile Chords

Like musical chords, people can distinguish "consonant" and "dissonant" superimposed vibrations. The evaluation criteria of vibrotactile consonance resemble those of musical chords.

We begin with an observation that superimposed vibrotactile stimuli are analogous to musical chords in which multiple notes are played simultaneously (see figure above). We designed a set of so-called “vibrotactile chords” based on musical chords. Then, we evaluated their degrees of consonance (harmony) that participants perceive through a perceptual experiment.

Experimental results indicate that participants can reliably rate the degrees of consonance of vibrotactile chords. We could establish a well-defined function that relates the degree of consonance to the base and chordal frequency of a vibrotactile chord.

The sensations described as “pleasant,” “smooth,” “even,” and “clear” were highly relevant to consonance, whereas those described as “jagged,” “bumpy,” “rough,” “sparse,” and “muddy” were closely associated with dissonance.

These findings have direct implications for the design of complex vibrotactile signals that can be produced by current wideband actuators.

Paper (ToH, 2014): link