Toward multi-finger haptic interaction: Presenting vibrotactile stimuli from proximal phalanges to fingertips

Multiple contacts with fingers have potentials to enhance the perceived haptic information both quantitatively and qualitatively. Although it is crucial to mount a multi-finger vibrator device on the fingers, it may restrict direct touch interaction with the user's hands. In this study, we propose a new approach to stimulating a fingertip with a vibrator attached on the dorsal side of the proximal phalanx. The objective of the paper is to investigate the propagation mechanism of that phenomenon and find requirements to design an effective device. The experimental results showed that the lateral clamp condition increased the fingertip vibration by 4.3 times compared to the vertical clamp. We also developed a prototype of the multi-finger vibrotactile display based on the hypothesized mechanism. Finger posture effects and the isolation capability were confirmed.