HapticWave: directional surface vibrations using wave-field synthesis.

Recent advances in haptic technology have focused on delivering haptic vibrations to the user's hand, either through touched physical surfaces (or objects) with embedded haptic devices or through worn (or held) haptic feedback devices such as a gloves or controllers. In most of these devices, the sensation of touch is controlled by modulating either the intensity or frequency of the haptic actuation. One missing piece is a sense of direction. Our hands perceive haptic actuation over an area rather than at a single point; by using the subtle phase and amplitude differences in the vibrations felt over an extended surface, humans can detect the direction of haptic vibrations, in addition to their intensity and frequency. This added dimension of directional vibration has not received significant attention in the haptic literature.