Ultrasound Rendering of Tactile Interaction with Fluids

When we interact with fluid media, e.g., with our hands, we experience a spatially and temporally varying pressure field on our skin, which depends on the density and viscosity of the fluid, as well as the relative motion between our hands and the surrounding flow. Ultrasound phased arrays stimulate skin in mid air by controlling pressure waves at particular spatial locations. In this work, we explore the connection between the pressure-based stimulation of ultrasound haptics and the actual pressure field experienced when interacting with fluid media, to devise a novel algorithm for ultrasound-based rendering of tactile interaction with fluids. Our algorithm extracts the target pressure field on a virtual hand from an interactive fluid simulation, and formulates the computation of the rendered pressure as an optimization problem. We have designed an efficient solver for this optimization problem, and we show results of interactive experiments with several fluid simulations.