Professor

Mechanical Engineering, POSTECH

Recent advances in skin-integrated vibrotactile haptic devices offer the capability of realizing a sense of touch, not only at the fingertips but across all regions of the body in virtual settings. However, many challenges lie ahead for creating realistic tactile interactions, owing to the complexity and lack of understanding of our somatosensory system and associated skin-actuator interactions. Here, we experimentally explored nearly all types of off-the-shelf vibrotactile sensors including an eccentric rotating mass (ERM), linear resonant actuator (LRA), tactor, and piezoelectric actuator interfacing directly to the skin surface and skin-like materials. Non-intrusive optical methods, including 3D Digital Image Correlation (DIC), Particle Tracking Velocimetry (PTV) and Eulerian Video Magnification (EVM), were implemented to decipher important continuum mechanic properties relevant to mechanoreception, including strain and acceleration at different depths in a skin phantom. Additional parameters, such as contact area, power input, frequency, and viscoelasticity, as well as customized perception tests, are considered to further correlate skin-actuator interactions and tactile perception. These findings will provide reference data for model validations and optimal strategies for developing next generation haptic devices.