Novel measurement method for physical activity based on electrostatic induction technique

Abstract

We here present a novel method for measuring human physical activity, which is based on detecting the electrostatic induction current generated by the walking motion under non-contact and non-attached conditions. This method involves measuring the electrostatic induction current flowing through a measurement electrode. A theoretical model for the electrostatic induction current generated because of a change in the electric potential of the human body is also proposed. By comparing the numerical integration value of the electrostatic induction current with the plantar surface area, it becomes obvious that this model effectively explains the behavior of the waveform of the electrostatic induction current flowing through the electrode. The normal walking motions of daily living are recorded using three measurement electrodes located in an ordinary house. The obtained results show that detailed information regarding physical activity such as a walking cycle can be estimated using our proposed technique. This suggests that the proposed technique, which is based on the detection of the walking signal, can be successfully applied to the estimation of human physical activity.