Presentation Methods of Multilevel Sensation Intensity on a Tactile Display

摘要

Tactile sensation of surface textures is an indispensable clue in a touch feel design task using a virtual environment or in a remote object manipulation task. In this paper, we discuss two methods to present multilevel tactile sensations followed by the introduction of a vibratory tactile display developed by the authors. The first method is to produce a pseudo-multilevel intensity on the basis of a binary dithering, which permits a reduced control load of the display. The exponent value of Stevens'power law was determined through an experiment. Regarding the second method employing direct amplitude control of display pins, the sensation intensity was scaled in terms of vibration amplitude based on a JND method. To evaluate the validity of the obtained scale, curves of intensity were presented on the scale. The result of the discrimination experiment exhibited a sufficiently high ratio of correct answer that suggested the availability of the scale for displaying multilevel textures.