User Exploratory Behaviour and Perception in Unconstrained Tactile Exploration Using Electrovibration

Abstract

Electrovibration offers potential to enrich virtual touch experiences with authentic tactile sensations on touchscreens. In controlled environments, responses to tactile stimuli may be anticipated, yet this predictability becomes uncertain in unconstrained settings due to dynamic factors like varied applied force, finger scanning speed, and sensory adaptation. To address this issue, we conducted a psychophysical study with 21 participants to investigate the effect of tactile
rendering parameters on user exploratory behaviour and perception during unconstrained exploration of artificial textures, aiming to discern a predominant tendency of interaction. Our results revealed, signal amplitude shapes human tactile
perception considerably during unconstrained exploration. We also observed, higher signal amplitudes were associated with lower finger scanning speeds, a trend tempered by significant individual differences, thereby affecting its practical effect. In contrast, the measured applied normal force and obtained finger movement pattern remained consistent and were not affected by different tactile rendering parameters. Notably, the rate of change of measured lateral force was found
to be a better metric for the perceived tactile dimensions than the lateral force magnitude. These findings enhance our understanding of perception and physics of such interactions, that could be vital for designing and delivering improved
haptic feedback on electrovibration-based tactile interfaces.