Investigation on Roughness and Pleasantness Perceptual Descriptors Through Tactile Stimuli Delivered by a Vibrotactile Device Mimicking Periodic and Isotropic Textures

The sense of touch relies on mechanical stimuli that are generated between the finger and the surface during the tactile exploration. Among them, the vibrational stimuli are fundamental to perceiving the fine textures. A vibrotactile rendering device has been used to deliver vibrational stimuli to testers. The stimuli were inspired by Friction-Induced Vibrations (FIV) measured by scanning periodic and isotropic textures, having, respectively, narrow-band and broadband spectral distributions. The stimuli have been parametrized with different frequency bands and amplitude levels. Through sensory campaigns, volunteers assessed the roughness and the pleasantness of the textures they imagined to be associated with the tactile stimuli, provided by the tactile rendering device. Statistical analyses have been performed on the sensory campaign's results. Frequency and amplitude of the stimuli have been strongly correlated with the perception of roughness and pleasantness descriptors. The obtained results have both confirmed previous knowledge and revealed new important insights on the features of vibration stimuli responsible for texture perception.