Flexible Inductive Coils for Wearable Cardiorespiratory Activity Monitoring

The implementation and utilization of flexible coils for monitoring cardiorespiratory activity is demonstrated in current paper. The equivalent parallel resonance impedance of single coil is measured, representing expectedly the cardiorespiratory activity induced volume changes in human body. Two chosen types of coils are researched in order to evaluate their difference in gaining access to cardiorespiratory activity: round shaped (O) coil and Figure-of-eight shaped (Fo8) coil. The Fo8 coils are found to provide better result in the case of monitoring cardiorespiratory activity than the O coils. However, the effect of concurrent movements is the highest for Fo8 coils. The immense influence of the choice of the position of coil, dependent on the shape, is concluded. The most suitable positions and configurations of coils are proposed.