UbiPoint: towards non-intrusive mid-air interaction for hardware constrained smart glasses

Throughout the past decade, numerous interaction techniques have been designed for mobile and wearable devices. Among these devices, smartglasses mostly rely on hardware interfaces such as touchpad and buttons, which are often cumbersome and counterintuitive to use. Furthermore, smartglasses feature cheap and low-power hardware preventing the use of advanced pointing techniques. To overcome these issues, we introduce UbiPoint, a freehand mid-air interaction technique. UbiPoint uses the monocular camera embedded in smartglasses to detect the user's hand without relying on gloves, markers, or sensors, enabling intuitive and non-intrusive interaction. We introduce a computationally fast and light-weight algorithm for fingertip detection, which is especially suited for the limited hardware specifications and the short battery life of smartglasses. UbiPoint processes pictures at a rate of 20 frames per second with high detection accuracy - no more than 6 pixels deviation. Our evaluation shows that UbiPoint, as a mid-air non-intrusive interface, delivers a better experience for users and smart glasses interactions, with users completing typical tasks 1.82 times faster than when using the original hardware.