Development of Adhesive and Suction Vibrators for Enabling Easy Fixation in Distantly-Presented Bone-Conducted...

Ultrasound can be perceived via bone conduction. This "bone-conducted ultrasound (BCU)" can be perceived even on distal body parts like the neck, chest, and upper limbs. Previous studies have suggested that "distantly-presented BCU" is expected to be applied to novel audio devices. However, in earlier studies on distantly-presented BCU, vibrators were pressed onto the body using an elastic band, which made the wearing process complicated and impractical. In this study, we proposed an adhesive vibrator that fixes using double-sided tape and a suction vibrator that attaches using the suction cup. We also evaluated their performance by estimating hearing thresholds. The results showed that BCU was perceptible at all sites where the vibrator could be fixed. In an adhesive vibrator, lower hearing thresholds were obtained by increasing the contact area and optimizing protrusion height of the vibrating surface, and detection thresholds comparable to conventional methods were obtained under the best condition. The suction vibrators were also able to be attached to the clavicle, where the adhesive vibrator could not fix. These findings provide valuable insights for the development of practical vibrator fixation methods.Clinical Relevance- These results indicate the potential to improve the wearability of vibrators, which has been one of the issues in audio devices using bone-conducted ultrasound, including hearing aids for the profoundly hearing impaired.