Active Type Surface Acoustic Wave Tactile Display

摘要

Reproduction of human haptic sensation has lately attracted attention for various fields, such as virtual reality, remote control of robots, computer interfaces and so on. Previously, a novel method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A pulse modulated driving voltage excites temporal distribution of standing SAW on a stator transducer. The distribution generated fluctuating friction on the surface of SAW substrate. When the surface with burst SAW is explored by fingertip through a slider, the fluctuation can be transformed into vibration and perceived as tactile sensation at mechanoreceptors in our finger skin. A prototype of the SAW tactile display is fabricated according to the principle. Rubbing the substrate through the slider, we can feel tactile sensations under a control depending on the rubbing motion. A controller for the prototype is developed. For evaluation of slider steel ball vibration, steel ball velocity under the control is measured. Two sets of the control parameters are selected so that operators can discriminate two kinds of roughness sensation. Effectiveness of the selection is evaluated through an experiment with a large number of subjects.