Detection for human respiration and human heartbeat under non-contact conditions

In this study, we developed an effective technique for measuring human respiration and human heartbeat using a noncontact and nonattached electrode. The technique requires measurement of the current generated due to the difference in capacitance between a given electrode and the human body. The subpicoamperes electrostatic induction current flowing through the electrode when placed a few centimeters from the subject is detected. We propose a theoretical model for the electrostatic induction current generated by the change in the capacitance caused by the movement of the body surface while taking a breath. This model effectively describes the behavior of the current flowing through the measurement electrode.