Flexible piezoelectret film sensor for noncontact mechanical signal capture by multiple transmission media  

作　　者：Xingchen Ma Qianqian Hu Lian Zhou Xinhao Xiang Yi Qin Ke Zhang Pengfei He Ying Dai Wenxin Niu Xiaoqing Zhang 

机构地区：[1]Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China [2]Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center),School of Medicine,Tongji University,Shanghai 201619,China [3]Department of Rehabilitation Sciences,Tongji University School of Medicine,Shanghai 200092,China [4]School of Aerospace Engineering and Applied Mechanics,Tongji University,Shanghai 200092,China

出　　处：《Nano Research》2024年第8期7643-7657,共15页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(NSFC,Nos.62201392,12174061 and 12374451).

摘　　要：Mechanical signal capture without physical contact has emerged as a highly promising research field and attracted tremendous attention due to its prosperous applications in household medical care,lifestyle monitoring and remote operation,offering users high level of safety,convenience and comfort.Moreover,noncontact sensing is ideal to maximize the immersive user experience in the human–machine interaction(HMI),eliminating interference to human activities and mechanical fatigue to the sensor,simultaneously.Herein,we report a self-powered flexible sensor integrated with irradiation cross-linked polypropylene(IXPP)piezoelectret film for noncontact sensing,featuring multi-functions to detect mechanical signals transmitted through solid,liquid and gaseous media and would facilitate their versatile practical applications.The folded-structure configuration of the sensor facilitates the improvement of the noncontact sensing sensitivity.For solid media,such as the rectangular wooden stick used in this study,the sensor can detect mechanical stimulus exerted at a distance of 100 cm.A system detection sensitivity up to 57 pC/kPa with a low detection limit of 0.6 kPa is achieved at a noncontact distance of 10 cm.Even when partly or completely immersed in water,the sensor effectively traces movement signals of human bodies underwater,demonstrating great advantages for non-inductive aquatic fitness training monitoring.Furthermore,due to the low acoustic impedance of piezoelectret film,speech recognition through gaseous medium is also achieved.We further introduce application demonstrations of the developed film sensors to monitor exercise postures and physiological signals without direct contact between human body and the sensor,displaying great potential to be incorporated into future smart electronics.This study commendably expands the application scope of piezoelectret materials,which will have profound implications for exploring novel intelligent human–machine interactions.

关 键 词：noncontact sensing piezoelectret multiple transmission media mechanical signal capture 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]