Morio Iwai, Kouya Sasaki, Naoki Honma, Koichiro Kobayashi
Vol. 12 (2023) p. 117-123

Recently, the number of health-related car accidents in Japan has been increasing. Most health conditions leading to traffic accidents are detectable by analyzing the fluctuation in blood pressure. In addition, cardiopulmonary arrest is an important condition that is linked to car accidents and should be studied along with respiration. Therefore, this study proposes a noncontact measurement system for cardiac dynamics and respiration using a coupled capacitance electrode. The measurement principle of the coupled capacitance electrode utilizes capacitive coupling with the human body. The human body, in particular the heart and the lung, is regarded as a dielectric. The displacement and fluctuation of the dielectric are indicated by capacitance changes in the coupled capacitance electrode. To validate the proposed system, we conducted measurements with the proposed system concurrent with chest circumference measurement using a strain gauge and electrocardiographic recording as references. The results revealed that the proposed system is capable of measuring respiration and cardiac dynamics.