CAREER: Making Tactile Waves: Somatosensation as Elastic Wave Propagation

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

Our sense of touch is far less understood than vision or hearing, and remains an under-utilized modality in computing systems. This is partly due to our limited understanding of the physical processes that relate the mechanics of touching an object to perception and movement. Recent research has shown that even lightly touching an object with a finger often excites elastic waves that travel throughout the hand and elicit responses in the sensory nervous system that evoke the conscious experience of touch contact in the brain, but the biomechanics that mediate this process are as yet unclear. The goals of this project are to elucidate aspects of the sense of touch that are affected by mechanical waves propagating in the body, to investigate the range of tactile sensations that accompany natural interactions with the hands, and to design new hardware technologies and algorithms for providing touch feedback in virtual reality. The work will quantitatively explore mechanisms of touch elicited wave propagation in order to catalyze advances in technologies for haptic sensing and feedback. Project outcomes will have broad impact by establishing a unique approach to teaching concepts from engineering and neuroscience to students at all levels, by using the sense of touch as a focal point and arena for creative hands-on learning, by enabling science outreach to the public through a radio show hosted by the PI, and by contributing to new technologies for aiding individuals with complex sensory impairments affecting the sense of touch. This project unites theoretical and empirical studies of touch-related viscoelastic waves with the engineering of new technologies for haptic sensing and display. To elucidate the mechanisms of human touch sensing and to realize technologies that can accurately address the haptic sense, a quantitative account of the mechanical signals involved is needed. Building on recent findings about touch-related elastic wave propagation in the hand, the viscoelastic waves produced during touch interactions with objects and surfaces, and the information they carry, will be measured and analyzed in order to: (1) Reveal the mechanics and information content of contact-elicited waves; (2) Create sensing methods that will be used to characterize tactile information in real world environments; and (3) Design haptic display technologies and rendering techniques to provide evocative haptic effects to the hand. The research will address a major gap in our understanding of tactile function by clarifying the biomechanical processes that link remote touch contact to neural processing and conscious perception. It will also aid efforts to explain specializations in the peripheral nervous system, such as the distribution, properties, and function of populations of vibration sensitive tactile receptors. Furthermore, it will yield unique wearable technologies for capturing and reproducing tactile sensations in the whole hand. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.