Haptic feedback design for a virtual button along force-displacement curves

In this paper, we present a haptic feedback method for a virtual button based on the force-displacement curves of a physical button. The original feature of the proposed method is that it provides haptic feedback, not only for the "click" sensation but also for the moving sensation before and after transition points in a force-displacement curve. The haptic feedback is by vibrotactile stimulations only and does not require a force feedback mechanism. We conducted user experiments to show that the resultant haptic feedback is realistic and distinctive. Participants were able to distinguish among six different virtual buttons, with 94.1% accuracy even in a noisy environment. In addition, participants were able to associate four virtual buttons with their physical counterparts, with a correct answer rate of 79.2%.