基于压电俘能器的自供电步态检测系统设计

Design of Self-Powered Gait Detection System Based on Piezoelectric Energy Harvester

鉴于压电元件既能感测压力动态变化,又能实现能量转换,采用两种压电模块设计了一款低成本、可穿戴、可自供电的步态检测系统。以矩形双晶陶瓷压电片作为压电俘能器能量转化单元,将人体运动机械能转换成电能,并利用其为步态检测系统供电;以柔性PVDF压电薄膜作为足底压力检测单元,完成人体站立、行走、跑步、跌倒等基本步态信息的检测。实验测试结果表明:人体在穿戴上述装置正常步行条件下,压电俘能器单位小时内提供0.731 J电能,可保障步态检测系统间隔423 s工作一次,且系统能够对人体的基本步态实现有效检测。

Considering that the piezoelectric element can not only sense the dynamic change of pressure,but also realize energy conversion,a low-cost,wearable,and self-powered gait detection system is designed by using two piezoelectric modules.The rectangular bicrystalline ceramic piezoelectric sheet is used as the energy conversion unit of the piezoelectric energy harvester,which converts the mechanical energy of human body motion into electrical energy,and it is employed to power the gait detection system.The flexible PVDF piezoelectric films are applied as the plantar pressure detection unit to realize the detection of basic gait information such as standing,walking,running,and falling of the human body.The experimental results show that the piezoelectric energy harvester can provide 0.731 J of electrical energy per hour when the human body wears the above device under normal walking conditions,which can ensure that the gait detection system works once at an interval of 423 s,and the system can effectively detect the basic gait of the human body.