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.