Consonance of vibrotactile chords.

This paper is concerned with the perception of complex vibrotactile stimuli in which a few sinusoidal vibrations with different frequencies are superimposed. We begin with an observation that such vibrotactile signals are analogous to musical chords in which multiple notes are played simultaneously. A set of so-called "vibrotactile chords" are designed on the basis of musical chords, and their degrees of consonance (harmony) that participants perceive are evaluated through a perceptual experiment. Experimental results indicate that participants can reliably rate the degrees of consonance of vibrotactile chords and establish a well-defined function that relates the degree of consonance to the base and chordal frequency of a vibrotactile chord. These findings have direct implications for the design of complex vibrotactile signals that can be produced by current wideband actuators such as voice-coil, piezoelectric, and electroactive polymer actuators.