Realism of Tactile Texture Playback: A Combination of Stretch and Vibration

Abstract

This study investigates the effects of two stimulation modalities (stretch and vibration) on natural touch sensation on the volar forearm. The skin-textile interaction was implemented by scanning three textures across the left forearm. The resulting skin displacements were recorded by the digital image correlation technique to capture the information imparted by the textures. The texture recordings were used to create three playback modes (stretch, vibration, and both), which were reproduced on the right forearm. Two psychophysical experiments compared the texture scans to rendered texture playbacks. The first experiment used a matching task and found that to maximize perceptual realism, i.e., similarity to a physical reference, subjects preferred the rendered texture to have a playback intensity of 1X – 2X higher on DC components (stretch), and 1X – 3.5X higher on AC components (vibration), varying across textures. The second experiment elicited similarity ratings between the texture scans and playbacks and showed that a combination of stretch and vibration was required to create differentiated texture sensations. However, the intensity amplification and use of two stimuli were still insufficient to create fully realistic texture sensations. We conclude that mechanisms beyond single-site uniaxial stimuli are needed to reproduce realistic textural sensations.