PVDF压电薄膜在结构监测中的应用初探

本研究对采秀ＰＶＤＦ压电薄膜监测结构的基本特性进行了较为系统的研究，分别做了ＰＶＤＦ压电薄膜监测结构的静态和动态响应实验，实验结果表明，ＰＶＤＦ压电薄膜监测结构应变的灵敏度提高，其静态响应的线性度好很好，而其动态响应同则有非线性和迟滞现象，对于用ＰＶＤＦ压电薄膜监测结构的冲击载荷也进行了初步的研究，实验结果表明采用ＰＶＤＦ压电薄膜可以实时监测结构所受的冲击载荷，并能及时反应出结构所受到的冲击损伤。     

采用共位配置的分布式压电敏感器和致动器的挠性结构的振动控制

本文研究采用共位配置的分布式压电敏感器和致动器的挠性悬臂梁的振动控制问题，其中敏感器由压电聚乙二烯氟化物薄膜（ＰＶＤＦ）制成，致动器由压电陶瓷（ＰＺＴ）或ＰＶＤＦ制成。本文首先建立系统的模型，设计了一种线性反馈控制方案，并应用无穷维空间的ＬａＳａｌｌｅ不变原理，证明了相应闭环系统的渐近稳定性。     

高频摆镜测试系统

以压电陶瓷（ＰＺＴ）为材料制成的摆镜处于较高频率的工作状态下,对其转动角、俯仰角和轴向位移量进行准确的实时非接触测试是必要的;本文介绍了利用二维连续分布式光电位置探测器ＰＳＤ作为敏感元件的测量高频摆镜动态性能的高速数据采集系统。利用“Ｍ”型光路实现了摆镜二维转角和轴向位移的同时测试;给出了一种二维ＰＳＤ的非线性快速修正方法,并利用１６ 通道的Ａ／Ｄ卡实现了４ 路模拟信号的ＤＭＡ 传送。     

高分子功能材料及在传感器中的应用——力学量传感器（边 五）

首先介绍了高分子压电材料ＰＶＤＦ的晶体结构及性能，在此基础上又介绍了高分子音频用传感器、超声波传感器、机器人用传感器等的应用情况。     

光物理研究中的薄膜热释电探测器

报告ＰＶＤＦ薄膜热释电探测器及其在非线性光学、激光等离子体物理等项研究中作为激光和其它辐射强度测量系统的设计和应用。     

PVDF及其共聚物的压电性和制备

分析了ＰＶＤＦ及其共聚物的压电机理，指出这些高聚物的压电性来自铁电体相的存在。在此基础上，探讨了提高聚合物压电性的制备方法。     

Visual Foxpro5.0与其他软件间的资源共享

本文介绍了 Ｖｉｓｕａｌ Ｆｏｘｐｒｏ提供的 ＯＬＥ技术及其应用方法,并引用了多个实例详细介绍 ＶＦＰ与 ＤＥＬＰＨＩ,ＥＸＣＥＬ,ＷＯＲＤ,ＶＢ,ＩＥ等应用程序间的相互联系。     

2D—SROP—1测量仪的相移装置设计与实现

介绍采用参考压电振动干涉法研制开发的高精表面粗糙度光学轮廓仪（２Ｄ－ＳＲＯＰ—１）。本文在阐述其工作原理之后。叙述了压电振动相移器ＰＺＴ及其驱动器的设计与实现。     

面向对象的中文PDF阅读器的设计与实现

本文介绍了面向对象的中文ＰＤＦ（ＰｏｒｔａｂｌｅＤｏｃｕｍｅｎｔＦｏｍａｎｔ）阅读器的设计与实现原理,首先对ＰＤＦ进行了简单介绍并指出开发中文ＰＤＦ阅读器的必要性,其次介绍了ＰＤＦ的结构并提出与之相适应的阅读器设计及实现方案。     

基于Virtex 系列FPGA的可编程嵌入式信号处理背板的开发设计

介绍了基于Ｖｉｒｔｅｘ系列ＦＰＧＡ和ＴＭＳ３２０Ｃ４０ＤＳＰ的可编程通用信号处理背板的设计和制作;并对Ｖｉｒｔｅｘ系列ＦＰＧＡ的性能和特点进行了分析;同时还叙述了可编程通用信号处理背板的调试;最后给出了背板应用开发实例。     

基于柔性基底的压电能量收集器的设计

以PDMS为柔性基底设计的PVDF压电薄膜新型压电能量收集器压电性能良好,柔韧性强,可适应复杂的振动环境,具有广阔的应用前景.首先设计了具有柔性基底的压电能量收集器的结构;其次,用PVDF颗粒采用静电纺丝法制备了PVDF压电薄膜;最后,实验表明设计的压电能量收集器在振动频率为25 Hz,振动幅度为2 mm的激励下,开路输出峰值电压为8.38 V,输出功率密度为6.32 μW/cm2;经Ansys有限元分析,发现增大激励源的振动幅度,可以提高压电能量收集器的开路输出电压和输出功率.     

A digital piezoelectric accelerometer with sigma-delta servo technique

This paper presents the design and performance of a direct digital accelerometer using oversampling sigma-delta servo electronics. The measuring system, also called an ‘electromechanical sigma-delta modulator’, is based on a piezoelectric measuring cell integrated inside the first stage of a second-order sigma-delta modulator. The piezoelectric measuring cell has a new structure in order to realize the acceleration sensing and the servo-loop summer. The active material used in an inexpensive and versatile piezoelectric polymer, polyvinylidene fluoride (PVDF). The accelerometer aims at a working range of ± 1 g and eight-bit resolution. It is suited for vibration measurement.     

基于PVDF压电传感器的车辆动态称重信号的研究

聚偏二氟乙烯(PVDF)是一种高性能压电材料,非常适合应用于车辆动态称重的环境。针对PVDF传感器的特点,提出用阻尼振动模型分析PVDF传感器产生称重信号的过程,给出称重信号的频谱特点,并在自主设计的实验平台基础上对该信号进行测量。实验结果显示:相对于低频噪声,称重信号主要分布在高频段,该特点为滤除系统噪声提供了依据。根据该特点设计称重系统可以有效地减少算法设计的复杂度,提高系统的测量精确性。     

基于PVDF的三维机器人触觉传感器有限元分析

为了解决压电层合板层间应力连续性问题,从而更为准确地预测传感器的实际输出,利用COMSOL Multiphysics对基于PVDF压电薄膜的三维机器人触觉传感器进行有限元建模。利用三维线性理论建立了压电层半解析轴对称有限元模型,得出分别沿三个方向施加单向力时触觉传感器各压电薄膜的电压响应。仿真结果与标定值之间的误差小于6%,验证了设计的合理性和可行性。     

测量多振动参数的PVDF传感器的设计

传统测量振动参数多采用压电式加速度传感器。设计了正弦和余弦形状PVDF传感器,可以测量位移、角位移、弯矩、剪力和功率流等多个振动参数。并以测量位移和功率流为例,对其结果进行了比较,结果表明:PVDF传感器测量更方便、数据更精确,功能更齐全、应用更广泛。     

基于PVDF的振弦式次声波传感器设计

针对当前用于次声波检测的次声波传感器存在的一些不足,设计一种基于PVDF的振弦式次声波传感器,建立了振弦、弹性元件、压电薄膜的数学模型,设计了调理电路,并对该传感器进行测试和验证。结果表明:该传感器具有能对次声波进行全方位接收、量程可调、灵敏度高、误差小等优点。     

Exact solutions for dynamic analysis of composite plates with distributed piezoelectric layers

Exact solutions are presented for analyzing dynamics of composite plates with piezoelectric layers bonded at the top and the bottom surfaces. The expressions for mechanical displacements, stresses, electric displacements and potential are derived from constitutive relations and field equations for the piezoelectric medium under applied surface traction and electric potential. The procedure is illustrated with a simply supported symmetric cross-ply (0°/90°/0°) graphite–epoxy composite plate covered with piezoelectric material polyvinylidene fluoride (PVDF). Results are in good agreement with those obtained from finite element model.     

通过PVDF阵列测量体积位移的实验研究

针对目前PVDF体积位移传感器的研究主要集中在经典边界条件(如简支、固定、自由等)、需要预知精确的边界条件等不足,提出通过伪逆方法结合Tikhonov正则化方法设计振动梁在任意未知边界条件下的压电式体积位移传感器的通用设计模型。以一未知边界条件的振动梁为例,用一组PVDF阵列测量其体积位移。在该梁表面均匀粘贴一组相同形状的矩形PVDF薄膜,然后通过所提出的新方法设计这组PVDF输出信号的加权系数,从而得到体积位移。实验结果表明这种传感器设计方法是可行的,并且不需要预知振动梁的边界条件或模态信息。     

Modeling of single and multilayer polyvinylidene fluoride film for micro pump actuation

Micro pumps are essential components of micro devices such as drug delivery systems. Large numbers of pumps have been proposed based on different actuating principles. Piezoelectric actuation offers advantages such as reliability and energy efficiency. Lead zirconate titanate (PZT) based piezoelectric actuation for micro pumps is predominantly explored despite its disadvantages such as brittle nature, low straining and difficulties in processing. Polymer piezoelectric materials like polyvinylidene fluoride (PVDF) could be promising replacements for PZT owing to their availability in form of films and good strain coefficients. Very limited literature on micro pump with PVDF as an actuator is available. In this paper, finite element analysis (FEA) model of a micro pump actuator using single and multilayer PVDF for actuation is developed in ANSYS^?. The model takes into account the influence of driving voltage and actuator geometry. The central deflection of the pump diaphragm which is instrumental in defining the pump performance is studied for driving voltages of 100?C200?V. The deflection of the pump diaphragm for single layer and multilayer actuation are determined from the model. It could be inferred from the initial part of the study that pump performance depends on driving voltage and actuator film thickness. In order to reduce driving voltage requirement multilayer stacked actuator is tried with four different configurations of the layers. It is concluded that stacking configuration of parallel energized straight polarity PVDF layers yielded best central deflection. An attempt is made to compare the performance of multilayer actuator with an equivalent single thick layer actuator. It is noticed that the multilayer actuator performance was better by about 101% when number of layers is doubled.