Flexible piezoelectric sensor based on PVDF-TrFE/Nanoclay composite nanofibers for physiological micro-vibration signal sensing

•Introduce a term: physiological micro-vibration signals (PMVS), and use one type of sensor (PMVS sensor) to achieve PMVS detection.•Nanoclay was introduced into PVDF-TrFE to improve the piezoelectric performance.•Design the arc-spring PI substrate to improve further the sensitivity of the PMVS sensor.•Design a wireless data acquisition system for the PMVS sensor and an Android app to form a PMVS monitoring system. Vibrations of human organs and tissues contain lots of useful physiological information, and these physiological vibrations can be called physiological micro-vibration signals (PMVS). Here, we designed wearable piezoelectric sensors (PMVS sensors) based on poly (vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)/(Na, Ca)0.33(Al, Mg)2(Si4O10)(OH)2·nH2O (Nanoclay) electrospinning nanofibers, parallel-stripes electrode integrated with impedance matching circuit, and arc-spring polyimide (PI) substrate for PMVS monitoring. The PMVS sensors with a tailor-made data acquisition system and a purpose-designed Android APP made up the PMVS acquisition system to collect throat vibration, pulse, respiration, heartbeat, and gait signals. The acquired data was compared with that by Polysomnography (PSG), and the time–frequency information of the two was highly consistent. Separate from traditional physiological signal monitoring equipment (e.g., PSG), the PMVS monitoring system obtains more information with fewer constraints. In parallel, the proposed PMVS monitoring system can acquire, quantify, and remotely monitor the physical health data, establishing a promising platform for next-generation homecare.