Flexible Four-Mode Crosstalk-Suppressed Sensor for Health and Motion Monitoring

Flexible multimodal sensors play a crucial role in health monitoring, human motion detection, detection of soft robots, etc. Nevertheless, achieving a multifunctional sensor, low-crosstalk of various sensing signals, and high sensitivity remains a significant challenge. In this study, through a reasonable allocation of functional layers, a compact-multilayer-structured four-modal sensor has been developed, which employs four different electrical parameters to detect and indicate four corresponding physical parameters: pressure, proximity, humidity, and temperature. The change impedance (Δ<i>Z</i>) of the interdigital electrode on the NaCl-impregnated paper indicated the change of humidity. It senses the temperature with the change resistance (Δ<i>R</i>) of the printed spiral coil. For pressure sensing, it can sense a wide range of pressures by detecting the capacity (Δ<i>C</i>) between the top and bottom electrodes. The multifunctional sensor can detect the proximity and departure of objects with change inductance (Δ<i>H</i>). Due to its multiple functional combinations, the sensor has broad application prospects in the fields of health monitoring and environmental perception and will promote the further development of monitoring systems for IOT.