Fingers of a Hand Oscillate Together: Phase Syncronisation ofTremor in Hover Touch Sensing

When using non-contact finger tracking, fingers can be classified as to which hand they belong to by analysing the phase relation of physiological tremor. In this paper, we show how 3D capacitive sensors can pick up muscle tremor in fingers above a device. We develop a signal processing pipeline based on nonlinear phase synchronisation that can reliably group fingers to hands and experimentally validate our technique. This allows significant new gestural capabilities for 3D finger sensing without additional hardware