磁敏Z元件位移传感器的研究

研制出一种新型磁敏Z元件位移传感器。并对磁敏Z元件的伏安特性和磁敏特性进行研究,给出了实验结果。设计了由信号采集、数据处理以及数字显示等电路构成的系统,实现了位移量的测量。由于Z元件的特殊性质,其应用电路较为简单。     

Z-半导体敏感元件原理与应用——(4)光敏、磁敏Z-元件及其应用

本文重点介绍光敏Z－元件、磁敏Z－元件的特性、典型应用电路、设计方法和应用示例,供广大用户利用光、磁敏Z－元件进行应用开发时参考。     

基于InSb磁敏电阻器的齿轮转速传感器

分析了InSb磁敏电阻器的工作原理和温度特性,讨论了利用偏置磁场作用于半桥磁敏电阻构成齿轮转速传感器的测试原理;针对半导体材料对温度十分敏感的特点,提出了利用浮动零点跟踪技术测试齿轮转速的方法,很好地克服了环境温度及磁场变化对磁敏电阻的影响.实验表明:其响应频率为0.5Hz～12kHz.     

强磁性金属薄膜磁敏电阻的特点与应用

一、前言强磁性金属薄膜磁敏电阻是一种磁敏传感元件.该元件不仅对磁场强度敏感,而且对磁场方向也非常敏感.这种磁敏传感元件具有灵敏度高、温度特性好、坚固耐用、应用范围广等优点.强磁性金属薄膜磁敏电阻,在国际上还是70年代中期刚刚问世的     

基于USB的气敏元件测试系统的设计

本文介绍了一种基于USB的气敏元件测试系统,给出了系统的硬件设计,阐述了用VC6.0实现数据采集和处理的软件设计.此系统可同时对多路气敏元件进行测试,并可对气敏元件的测试数据实时显示,具有绘制特性参数曲线、数据统计和分档等功能,实现了对气敏元件性能参数的高效测试.     

三维磁敏传感器的设计及误差分析

采用三维磁敏传感器有助于降低磁场测量系统的复杂性和提高磁场测量速度.介绍了基于霍尔元件的三维磁敏传感器的设计方法,分析了霍尔元件的粘贴角度偏差、传感器的体积对测量精度的影响,并对传感器的总体误差进行了估算,其分析结果对三维集成磁敏传感器的设计具有指导意义.     

新型InSb-In薄膜磁阻式振动传感器的设计

介绍了一种用InSb-In共晶体薄膜磁敏元件制成的准全方位振动传感器.它由两对对称轴方向互相垂直的InSb-In磁敏元件构成,可将检测方位范围由一维扩展到现在的二维平面,并用单片机P87LPC760对传感器信号进行处理,应用中可提高检测信号的准确性.经实测, 在机械振动的中低频率检测范围内,传感器的有效频带不窄于4～760Hz,其通频带内信噪比为30～32dB,经换算得灵敏度为16mV/gn.同时,得到传感器振动强度大小与磁敏电阻器输出信号关系曲线.     

光敏Z元件角速度传感器研究

为了对转动装置的转速进行实时检测,研制出一种光敏Z元件角速度传感器。对光敏Z元件的特性进行了测试,其伏安特性曲线呈"L"型;随着光照度增加,阈值点向左上方移动。运用半导体理论对光敏Z元件的特殊性质进行了分析。利用光敏Z元件作为光电转换器,并用红外光源和信号处理电路设计一种光电式角速度传感器,其分辨力能达到0.4 rad/s,并能实现将转速量转换为数字脉冲信号输出的功能。由于光敏Z元件的特殊性质,该传感器具有电路简单、响应速度快、光谱响应范围宽的特点。     

基于InSb磁敏电阻器的脉冲涡流信号处理方法研究

脉冲涡流检测方法是涡流检测技术的一个新兴分支。分析了InSb磁敏电阻器作为脉冲涡流检测元件的工作原理。应用InSb磁敏电阻器的涡流探头检测金属裂纹特征的信息提取方法。对采集的信号首先通过同步累加法处理后再经多项式拟合、小波变换实现对信号的滤波与平滑,最终选用小波变换提取裂纹的特征。实验表明:采用InSb磁敏电阻器作为脉冲涡流检测敏感元件,具有较高的裂纹灵敏度,且可以较好地反映裂纹的深度。     

ZnSnO_3-乙醇气敏元件特性及其可靠性研究

本文报导了ZnSnO_3气敏材料电导率随温度变化的测试结果.以它为基体材料制备乙醇气敏元件,对其电阻随乙醇气浓度变化的特性进行了讨论.元件的强制失效实验分析表明,该类元件在正常工作条件下,处于高浓度检测气体气氛中不发生“中毒”和失效;还给出了一些对生产工艺较有意义的数据.     

InSb磁阻元件与传感器的进展

InSb磁敏电阻及传感器是磁敏元件与传感器的主要品种之一。对这类元件及传感器的工作原理、结构和性能等分别作了简要介绍。其中有分立型磁敏元件,磁敏无接触电位器、旋转传感器、精密小角度角位移传感器、直线位移传感器、压力传感器和图形识别传感器等。除介绍主要技术性能之外,还简要介绍了它们的应用实例。     

基于Z元件的数字化智能传感器的设计与实现

根据Z元件的特性,使Z元件与单片机相结合,并用最小二乘法对其输出电压与温度之间仔在非线性关系进行拟合,最终得到了一种集数字信号处理和通讯为一体的数字传感器.实验证明该传感器的性能稳定、信号传输误差小,是具有自整定、自寻址功能的智能传感器.     

力敏Z元件的研究及在触觉传感器上的应用

介绍一种新型力敏元件Z元件的制备、机理和特性。并阐述了用力敏Z元件研究触觉传感器的前景和特点     

基于显微视觉的微小型零件跟踪系统

微装配过程中的运动目标跟踪是一个新兴的研究方向。构建了一个由CCD相机、显微镜头、电控云台和图像处理模块组建的、针对微小型零件的显微视觉跟踪系统。为克服显微视场范围小的局限性,提出一种基于SIFT特征点的模板匹配和Kalman预测相结合的跟踪算法,通过Kalman预测实现在局部范围内的模板匹配,利用SIFT特征对模板匹配的结果进行校正和更新。实验结果表明：提出的跟踪算法能得到稳定的目标局部特征,并准确地跟踪到目标,对亮度变化、成像模糊等影响因素有较强的适应能力。     

Lattice Boltzmann method for microfluidics: models and applications

The lattice Boltzmann method (LBM) has experienced tremendous advances and has been well accepted as a useful method to simulate various fluid behaviors. For computational microfluidics, LBM may present some advantages, including the physical representation of microscopic interactions, the uniform algorithm for multiphase flows, and the easiness in dealing with complex boundary. In addition, LBM-like algorithms have been developed to solve microfluidics-related processes and phenomena, such as heat transfer, electric/magnetic field, and diffusion. This article provides a practical overview of these LBM models and implementation details for external force, initial condition, and boundary condition. Moreover, recent LBM applications in various microfluidic situations have been reviewed, including microscopic gaseous flows, surface wettability and solid–liquid interfacial slip, multiphase flows in microchannels, electrokinetic flows, interface deformation in electric/magnetic field, flows through porous structures, and biological microflows. These simulations show some examples of the capability and efficiency of LBM in computational microfluidics.     

Numerical model of a nanoelectric line from a graphene component

The paper discusses the numerical model and provides the analysis of a graphene coaxial line suitable for sub-micron sensors and other applications utilized especially in biomedicine. In the wider perspective, the areas and disciplines targeted by the presented concept include biology, medicine, prosthetics, and microscopic solutions for modern actuators or SMART elements. The proposed hybrid numerical model is based on analyzing a periodic structure with high repeatability, and it exploits the conception of a graphene polymer having its basic dimension in nanometers. The model simulates both the transient analysis and the actual random motion of an electric charge in the structure as the source of spurious signals, and it also considers the harmonic signal propagation along the structure; moreover, the model examines whether and how the signal will be distorted at the beginning of the modeled electric line, given the various termination versions. The results of the analysis are necessary for further use of the designed sensing devices based on graphene structures.     

High-Voltage Dielectrophoretic and Magnetophoretic Hybrid Integrated Circuit/Microfluidic Chip

A hybrid integrated circuit (IC)/microfluidic chip is presented that independently and simultaneously traps and moves microscopic objects suspended in fluid using both electric and magnetic fields. This hybrid chip controls the location of dielectric objects, such as living cells and drops of fluid, on a 60 $times$ 61 array of pixels that are $30 times 38 mu hbox{m}^{2}$ in size, each of which can be individually addressed with a 50-V peak-to-peak dc-to-10-MHz radio-frequency voltage. These high-voltage pixels produce electric fields above the chip's surface with a magnitude $vert vec{E}vert approx 1 hbox{V}/muhbox{m}$ , resulting in strong dielectrophoresis (DEP) forces $vert vec{F}_{ rm DEP}vert approx 1 hbox{nN}$. Underneath the array of DEP pixels, there is a magnetic matrix that consists of two perpendicular sets of 60 metal wires running across the chip. Each wire can be sourced with 120 mA to trap and move magnetically susceptible objects using magnetophoresis. The DEP pixel array and magnetic matrix can be used simultaneously to apply forces to microscopic objects, such as living cells or lipid vesicles, that are tagged with magnetic nanoparticles. The capabilities of the hybrid IC/microfluidic chip demonstrated in this paper provide important building blocks for a platform for biological and chemical applications. $hfill$[2009-0142]      

Dynamic moment analysis of the extracellular electric field of a biologically realistic spiking neuron

Based on the membrane currents generated by an action potential in a biologically realistic model of a pyramidal, hippocampal cell within rat CA1, we perform a moment expansion of the extracellular field potential. We decompose the potential into both inverse and classical moments and show that this method is a rapid and efficient way to calculate the extracellular field both near and far from the cell body. The action potential gives rise to a large quadrupole moment that contributes to the extracellular field up to distances of almost 1 cm. This method will serve as a starting point in connecting the microscopic generation of electric fields at the level of neurons to macroscopic observables such as the local field potential.