A new design of haptic texture display - Texture Display2 - and its preliminary evaluation

The authors describe a new design of haptic texture display consisting of fifty vibratory pins that evoke a virtual touch sensation of textured surfaces contacted to the user's fingerpad. A pin drive mechanism was fabricated by adjusting a natural frequency to expand the displacement of a piezoelectric actuator efficiently. An improved control system enabled fine amplitude changes in 200 steps. Sensation intensity was scaled and indicated by a power function of pin amplitude. As a fundamental evaluation data, we measured the difference threshold of an object's spatial frequency presented on the display, regarding four intensity waveforms. Moreover, matching tests between real and virtual textures were performed to evaluate the quality of presentation.