Sensitive cushion based on hetero-core fiber optics for unconstraint sitting posture monitoring

Recently, sitting posture monitoring has been focused in the fields of health management in order to improve the quality of Sedentary Lifestyle. We propose an unconstraint sitting posture monitoring method using a sensitive cushion based on hetero-core fiber optics. The hetero-core fiber optic sensor has several advantages for unconstrained human behavior monitoring such as single-mode transmission usage, flexibility and light-weight. Therefore, the hetero-core sensors can be unobtrusively embedded inside the cushion, which enables the sitting posture to be monitored without conscious to the sensor. We designed a bending structure with a hetero-core portion and examined its force properties. We successfully demonstrated that the developed sensitive cushion could detect body moving of a subject on a chair. The proposed method could monitor body moving in the case that the subject sat down on several moving patterns on the chair.