Wireless Battery‐Free Flexible Sensing System for Continuous Wearable Health Monitoring

Abstract

With the spread of infectious diseases around the world, health monitoring is gaining importance as a key technology for disease prevention. Contact health monitoring inevitably causes a potential for disease transmission between patient and physician. Hence, the research on contactless health monitoring between patients and medical workers leads to increased attention. Current systems provide various wireless monitoring solutions, but two dilemmas need to be solved urgently. The first is replacing the rigid substrate with an all‐flexible structure. The second is the ability to wireless multiple parameters detecting. Herein, a wireless battery‐free flexible sensing system for continuous and contactless wearable health monitoring. The system consists of three sensing modules integrated with inductance‐capacitance resonators for monitoring temperature, humidity, and pressure while the sensitivity reaches 710.1 kHz %RH−1, 19.2 kHz Pa−1, and 630.1 kHz °C−1, respectively. All‐flexible structure satisfies the wearable requirements for contactless health monitoring. The continuous monitoring of daily activities demonstrates the potential of the wireless battery‐free sensing system for obtaining physiological status in epidemic prevention and control.

Wireless Technologies in Flexible and Wearable Sensing: From Materials Design, System Integration to Applications

“…Other monolithically integrated wireless sensing systems include organic conductive nanocomposite‐based RFID sensor tag (Figure 10d), [ 177 ] polypyrrole nanoparticles‐based RFID wireless sensor system (Figure 10e), [ 178 ] and graphene oxide‐based inductance–capacitance resonators. [ 179 ]…”

Single-Line Multi-Channel Flexible Stress Sensor Arrays

“…RLC resonant sensing has wide applications in areas such as wireless communication, biomedical, and environmental monitoring. In wireless sensor networks, it enables wireless monitoring and data transmission of various physical parameters [ 31 ] (temperature, humidity, etc.). In bio-sensors, it can be used to monitor physiological parameters [ 5 ] and disease indicators within the human body.…”

“…To address this challenge, the single-line multi-channel (SLMC) signal measurement has been developed, enabling simultaneous detection of multiple sensor signals through one or two signal wires [ 15 , 16 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 ]. By utilizing SLMC technology, the flexible stress sensor array can measure the magnitude and location of the stress by one or two signal lines.…”

“…This approach effectively reduces the number of signal wires, enhancing stability, deformability, and reliability, and facilitating the application of flexible stress sensor arrays in bionic robots and rehabilitation medicine. Existing research has successfully implemented various mechanisms including RLC series resonant sensing, transmission line sensing, ionic conductor sensing, triboelectric sensing, piezoresistive sensing, and distributed fiber optic sensing [ 15 , 16 , 28 , 31 , 32 , 33 , 34 , 36 , 41 , 42 , 43 , 44 , 45 , 46 ]. These advancements have demonstrated promising potential in the domains of bionic robots, medical rehabilitation, and other related fields, as depicted in Figure 1 .…”

High‐Resolution Intaglio Transfer Printing of Silver Nanowires for Wearable Electrophysiological Sensors

“…Flexible electronic skin (E-skin) can detect and interpret various physiological signals upon contact with the human body, [1][2][3][4][5][6] which plays a crucial role in human-machine interface devices, [7,8] healthcare monitoring systems, [9][10][11] soft robotics, [12,13] intelligent prosthetics, [14,15] virtual reality, and augmented reality. [16,17] In particular, non-invasive E-skin is well suited for monitoring personal physiological signals during daily activities by continuously detecting and interpreting physiological signals upon contact with the human body.…”