Detection of human arm approaching direction based on electrostatic coupling in human body communication

A human body can be considered as a communication channel in which the electrical signal propagates through the body based on an electrostatic coupling mechanism when the frequency is sufficiently low. Since the human body approximately acts as a conductor in this case, we can detect the existence of the human body by measuring the corresponding electric filed variation in a close proximity of the human body. In this study, we aim to detect the approaching direction of a human arm based on this electrostatic coupling mechanism in human body communication for application to a user-machine interface. We first provide an appropriate explanation of this detection system based on the electrostatic coupling mechanism, and then conduct not only a computer simulation but also an experiment to validate the feasibility of the proposed detection system.