用于生物组织弹性模量检测的压电触觉传感器  

Design of piezoelectric tactile sensors for elastic modulus detection of biological tissues

作　　者：胡捷 刘仁鑫[1] 杨卫平[1] 段武茂[1] 文建萍[1] Hu Jie;Liu Renxing;Yang Weiping;Duan Wumao;Wen Jianping(College of Engineering,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]江西农业大学工学院,南昌330045

出　　处：《仪器仪表学报》2025年第2期325-334,共10页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金项目(31960683)资助。

摘　　要：在粘膜下肿瘤早期诊断中,使用内窥镜获得触觉反馈信息有助于提高生物组织的弹性模量检测精度,进而精准定位血管,确定生物组织的健康状况与类型,从而提高治疗质量。故设计了一种适用于安装在医用内窥镜上的微型压电触觉传感器(PTS,φ=2.0 mm),该器件主要由两个刚度不同的组件(内部和封装组件)及PVDF压电层构成。基于串联弹簧模型和压电传递方程,建立了PTS/生物组织接触传感数值模型,深入分析PTS的生物组织弹性模量传感规律;采用微机电系统(MEMS)制造工艺,制备了PTS样机,同时搭建PTS/生物组织动态载荷测试平台对猪胃中不同人工肿瘤软/硬特性测试和模型验证。计算结果表明,当PTS接触较硬的生物组织时,大部分的轴向载荷由内部组件-铜球传递,PDMS封装层的形变很小。相反,当PTS接触较软的生物组织时,PDMS封装层产生的形变较大。其次,PVDF层靠近内部组件(铜球)的接触区域产生的响应电压(V)与应力(σ)最大,其与封装层接触区域产生的V与σ较小;实验结果表明,内部组件与封装组件响应电压之比(V_(1)/V_(2))与生物组织弹性模量(E_(t))成线性关系,0.2~3.5 MPa内,随E_(t)增大,V_(1)/V_(2)增大,且与模型计算结果相吻合。因此,上述测量方法可有效提取生物组织的生物力学信息。In the early diagnosis of submucosal tumors,using endoscopy to obtain tactile feedback information can help improve the accuracy of elastic modulus detection of biological tissues,thereby accurately locating blood vessels,determining the health status and type of biological tissues,and improving the quality of treatment.In this paper,a novel micro piezoelectric tactile sensor(PTS,ϕ=2.0 mm)suitable for installation on an endoscope to detect the elastic modulus of biological tissue is designed.This device mainly consists of two components with different stiffness(internal and packaging components)and a polyvinylidene fluoride(PVDF)piezoelectric film.Simultaneously,based on the series spring model and piezoelectric transfer equation,a numerical model for PTS/biological tissue contact sensing has been established,and the sensing law of biological tissue elastic modulus and its energy conversion law of PTS have been deeply analyzed via the Comsol Multiphysics.Meanwhile,a PTS prototype was prepared using a MEMS manufacturing process,and a PTS/biological tissue dynamic load testing platform was conducted to test the soft/hard characteristics of different artificial tumors in the pig stomach for validating the above model.Moreover,the calculation results show that most of the axial load is transmitted by the internal components-copper balls,and the deformation of the PDMS encapsulation layer is minimal when PTS comes into contact with harder biological tissues.On the contrary,the PDMS encapsulation layer undergoes greater deformation when PTS comes into contact with softer biological tissues.The calculation results also indicate that the response voltage(V)and stress(σ)generated in the contact area of the PVDF layer near the internal component(copper ball)are significantly higher than those in the contact area with the packaging layer,which reveals the mechanical-electric field coupling and energy transfer process of PTS.Furthermore,the experimental and computational results confirm that the PTS device,with a 2.0 mm di

关 键 词：生物组织 触觉传感器 压电 弹性模量 

分 类 号：TH11[机械工程—机械设计及理论]