Affiliations: [a] Department of Bioengineering and Robotics, Graduate
School of Engineering, Tohoku University, Aoba-ku, Sendai, Japan | [b] Graduate School of Biomedical Engineering, Tohoku
University, Aoba-ku, Sendai, Japan | Université Laval, Canada | Tohoku University, Japan
Abstract: This study describes the development of a sensor system for
measuring human scratching motion. In order to measure the scratching motion,
we focus on the mechanical vibration between the nail and the skin that is
scratched. Scratching sounds, induced by the vibration, change according to the
scratching intensity or the skin condition. Therefore, the information on the
scratching sounds can help us to evaluate the characteristics of scratching. In
this study, a nail-mounted compact microphone sensor for measuring human
scratching sounds is designed and fabricated. First, the ability of the
proposed sensor to measure scratching sounds is investigated. The feasibility
of this sensor has been verified. Next, the power spectrum density is
calculated from the sensor output to investigate the characteristics of the
scratching sounds according to the scratching intensity. It was found that
frequency components increased with an increase in the contact force during
scratching. The results suggest that it is possible to evaluate the scratching
intensity by using the proposed sensor system.
