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Title: Psychophysical Validation of Interleaving Narrowband Tactile Stimuli to Achieve Broadband Effects
Current wearable haptic display technology is limited by the lack of broadband tactors capable of delivering rich haptic effects across the entire perceptible frequency range. Audio speakers are often used in laboratory studies as broadband tactors, but it is difficult to attach them to skin and maintain contact during movement. Commercially-available narrowband tactors are small, low in cost and power efficient. We investigate the idea of interleaving narrowband tactile stimuli to achieve broadband effects. Twelve participants performed pairwise discrimination of two stimulus alternatives using two broadband tactors. One alternative was a broadband vibration composed of the sum of a mid- and a high-frequency vibration, delivered by a single tactor. The other alternative consisted of the mid-frequency component delivered by one tactor and the high-frequency by the other. The upper arm was chosen for stimulation because the tactors can be placed within the two-point limen of the skin. The sensitivity index results were significantly below 1.0, the criterion for discrimination threshold, thereby confirming that broadband haptic effects can be achieved by placing narrowband tactors with mid and high resonant frequencies within the skin’s spatial resolution. We provide guidelines and examples of applying our findings to the design of wearable haptic displays.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
World Haptics Conference 2021
Page Range / eLocation ID:
709 to 714
Medium: X
Sponsoring Org:
National Science Foundation
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