Enhanced Haptic Perception of Virtual Protrusions Using a Focused Ultrasound-Driven Thin-Film Actuator

Focused ultrasound devices can provide haptic sensations in a non-contact manner without constraint or weight. However, the presentation power is relatively low compared to contact-type devices. This study proposes a haptic presentation actuator that enhances the perception of virtual protrusions generated by a focused ultrasound device. Skin deformation is important for perceiving protrusion shapes. An actuator was designed by the research team consisting of a thin film and a contact body that induces skin deformation. Finite element simulation analysis and psychophysical experiments were conducted to determine the shape factor of the actuator. Questionnaires were conducted with experimental participants to determine the device’s impact on the experience in a virtual reality. As a result, the proposed device enabled the presentation of pressure perception with static pressure as small as 3 mN without vibrotactile sensation, which was previously difficult. Furthermore, it was found that the protrusion shape can be presented, improving the reality of protrusion shapes in a virtual reality setting.