A fingernail-mounted tactile display for augmented reality systems

There have been many efforts to present skin tactile information to the fingertips. In these studies, however, the tactile stimulus has been presented to the pad side of the finger. In that approach, it is difficult to superimpose virtual tactile information on the tactile information of the real world. Consequently, this paper proposes a tactile display device in which vibration is applied to the fingernail side, not to the pad side of the finger, so that a virtual undulating sensation can be superimposed on the real-world sensations obtained during the scanning action of the finger. The proposed device is based on the phenomenon that when a vibration is applied while the finger is scanning an object, a perception of undulation rather than of vibration is produced. This study measures the pressure change produced on the pad side of the finger in such a scanning operation and investigates the mechanism that causes the perception. The vibration timing required to present an arbitrary virtual convex width is determined by a psychophysical experiment.