Design and fabrication of wearable male-type radio button-shaped vibrotactile actuators

Vibrotactile actuators have been studied in a variety of wearables that require actuation feedback because of their accurate and rapid feedback. To provide robust and reliable feedback to users, wearable vibration actuators must be seamlessly integrated into smart clothing to deliver vibrotactile stimulation of the appropriate intensity. In order to solve the vibration attenuation problem due to clothing fabric, and seamlessly integrate the actuator, wearable male-type radio button-shaped vibrotactile actuators (WMVAs) were designed and fabricated. The WMVAs were designed with a structure in which a linear resonant actuator was housed in a stud, and vibration was passed through the fabric and transferred to the skin through the cap. Three WMVAs were fabricated, one with a cap of standard size and thickness, the second with a thicker cap than the standard, and the third with a wider cap than the standard. In order to investigate the vibration transmission performance of the WMVA, vibration perception experiments were performed on various body parts of the subjects. As a result, the vibration perception of the WMVA was statistically significant in all tested body parts. Using the WMVA, the mean value of vibration perception was 2.743, while that without a cap and stud was 2.062. The mean value of the vibration perception of the actuator with a cap 2.78 times thicker is 2.736, compared with the standard actuator value of 2.512. The average value of vibration perception of an actuator with a 2.78 times larger cap than the standard size is 2.743.