Effect of Auditory Feedback on Tactile Intensity Perception in a Touchscreen Application

This article presents the effect of auditory feedback on tactile intensity perception, which may be of interest to haptic or audiotactile interaction engineers. An experimental setup consisted of a touchscreen, an electrodynamic shaker, and a closed-back headphone for a subject to interact with the touchscreen and to feel audiotactile feedback. In the experiment, participants were asked to judge perceived tactile intensity, using the magnitude estimation method, in the absence and presence of simultaneous auditory feedback. All data collected from the subjects were analyzed statistically, and then the effect of auditory feedback was investigated focusing on the following aspects: whether the presence of auditory feedback changes perceived tactile intensity, whether the frequency component of auditory feedback affects tactile intensity perception, and whether the coincidence of tactile and auditory frequencies influences on tactile intensity perception. Besides, changes in Stevens's exponent were analyzed to discuss how tactile intensity perception varies due to the auditory feedback. Finally, an equal intensity contour, in the domain of sensation level and frequency of tactile stimulation, was drawn. It can be applied to adjust the level of tactile stimuli for haptic feedback designers to provide a constant perceived tactile intensity considering the presence of auditory feedback.