Coupling Effect and the Structural Schematic Design of Decoupled Micromachined Vibrated Gyroscope

微机械振动陀螺是近几年发展起来的新型惯性元件 ,其误差源主要有微机械结构的 Brown-ian噪声、电路噪声、机械耦合误差及电子机械耦合误差等 ,这些误差严重影响陀螺仪的精度 .本文提出了单级隔离耦合和双级隔离耦合的结构方案 ,有效减小机械耦合误差 ,提高精度 .Silicon micromachined gyroscope is a new type of inertial sensor developed in recent years, whose error resource often comes from brownian noise, electronic noise, mechanical coupling effects and electromechanical crosstalk , etc. These errors would affect the precision of gyroscope greatly.The structural schemes of the single decoupled and double decoupled were proposed in this paper. The mechanical coupling error could be reduced greatly and be made more precise by applying these types of structure

Structural design and performance analysis on cantilever beam micromachined tunneling gyroscope

介绍了电子隧道效应在微机械陀螺仪中的应用,根据电子隧道效应的特点与要求提出了隧道陀螺仪的结构方案,利用ANSYS进行系统模态分析、静电-结构的耦合场分析及系统的性能分析。讨论了系统的机械灵敏度及隧道电流与隧道电极间隙的关系。Application of electron tunneling effect in micromachined gyroscope is described.According to the prerequisite and characteristic of tunneling effect,a scheme of gyroscope structure is presented.Modal analysis and electrostatic-structure coupling analysis and performance analysis are described by using ANSYS software.Mechanical sensitivity and relation between the tunneling current and the distance of electrode are discussed.福建省自然科学基金资助项目(A0110003);; 福建省教育厅B类科研项目(JB03283

The fabrication technology of silicon tip

隧道硅尖的制备是微机械隧道传感器制作的一个重要组成部分 ,通过对ICP刻蚀和湿法各向异性刻蚀工艺制备硅尖实验的研究 ,得到了合适的工艺条件以及较理想的硅尖The fabrication technology of silicon tip is an important constituent of micro tunneling sensor. Through studying the process of ICP and anisotropic etching associate with bonding technology, ideal silicon tips and suitable process conditions were obtained

Analysis of The ICF Surface Cracks Evolution

低周疲劳表面裂纹演化可能具有非线性动力学特征。对 1Cr18Ni9Ti光滑试样进行了低周疲劳实验 ,在对裂纹进行分类的基础上 ,将裂纹演化划分为多裂纹相互作用和局域主裂纹控制两个阶段。从非线性动力学角度给出了短裂纹的新的定义。指出裂纹演化两个阶段对材料疲劳损伤破坏过程的贡献。There may be non linear dynamic characteristics during the evolution of the surface Low Cycle Fatigue(LCF)cracks system.After the LCF experiment on the smooth sample of 1Cr18Ni9Ti done,the viewpoint that the process of fatigue cracks evolution is composed of two phases is proposed.The two phases are named as the Multi cracks Interaction(MI)and the Local Dominant cracks Controlling(LDC).It can be seen from the statistical investigation that the traditional short crack evolution phase is essentially the MI,and is in disorder.It is the growth and coalescence of the local dominant cracks that induce the broken of material.The two phases in the fatigue cracks evolution are essentially the result of the non equilibrium bifurcation of the system.It is a transition from discorder to order.国家自然科学基金!资助项目 (195 72 0 5 1

Electrospun Aligned Polyethylene Oxide Nanofibers

采用一种新颖的纺丝工艺制备定向聚氧化乙烯纳米纤维.该工艺就是将两个平行的接地金属导体置于收集板的两侧,电镜图实验结果表明采用该一步法可以制得200~490nm左右的PEO定向纳米纤维,而且随着电极之间距离的增大,在拉伸的充分性和电场的共同作用下,纳米纤维先减小后增大.实验还证实定向纤维是电场而非结构作用的结果.An novel and facile electrospinning method, in which two parallel grounded metallic conductors are introduced to change electric field as auxilliary electrodes besides collector, is used to prepare oriented polyethylene oxide (PEO) nanofibers. SEMs of experiment results show that aligned nanofibers which diameters are around 200~490 nm can be achieved by this one-step method, and the diameters of nanofibers decrease at first when the distance is smaller than 2 mm, then increase if the distance is larger than 2 mm with the increasing distance between two parallel conductors as the combination of strectching sufficiency and decreasing electric field strength. It also can be verified that the aligned nanofibers mainly caused by changed electrostatic field and not by structure.海归学者科学研究基金资助;; 厦门大学创新项目研究基金项目资

基于AGC闭环控制的谐振式压力传感器驱动仿真及接口电路设计

谐振式压力传感器利用正反馈原理,构成包括机械谐振子在内的机电一体的高品质闭环谐振系统,闭环拓扑结构对保持机械谐振器振荡的稳定性和可靠性起着重要作用。本文针对一种典型结构的静电驱动电容检测谐振式压力传感器,在分析工作原理的基础上,构建了其行为级闭环自激仿真模型,在MATlAb中对自激回路的起振情况进行了仿真;最后设计了基于AgC的闭环控制电路。he theory of positive feedback is used by resonant pressure sensor to form highquality mechanical and electrical integration close-loop resonant system including mechanical harmonic oscillator,closed loop topology structure plays an important role to keep the stability and reliability of the mechanical resonator oscillation.In this paper,a kind of typical structure of the electrostatic drive and capacitance detection resonant pressure sensor is analyzed.The behavior model of the closed-loop simulation of self-excitation is constructed based on analyzing the working principle,excitation circuit of the oscillation starting are simulated using MATLAB.Finally,the closed-loop control circuit based on AGC is designed

Design of 13.56 MHz RFID Tag Antenna and Analysis of Fabrication by Screen Printing

阐述了基于13.56 MHz射频印刷标签天线具体的设计方法和制造工艺。以ICOdE芯片为例,描述了整个标签天线结构设计方法,设计并印刷出天线。通过对印刷天线的分析,进而得出印刷天线电感及电容的获得主要取决于设计结构的结论,而对印刷工艺而言,印刷工艺的优化目标之一则是获得较低的天线阻值,从而得到较高的天线品质因子Q,获得理想的天线综合性能,满足感应距离的需要。A design method and manufacturing process of 13.56 MHz RFID tag antenna by screen printing is described.A test structure is designed and screen printed taking the ICODE chip as example.The conclusion is that the inductance and capacitance of a printed tag antenna are dependent mainly on the structure of design.For the printing process,one of the optimization objectives is to acquire a lower antenna resistance,a higher quality factor Q and desired properties to meet the needs of remote sensors

Air filtration performance of nanofibrous membranes electrospuned with different nanofiber diameters

使用静电纺丝的方法,制造出不同直径的纳米纤维薄膜,在低风速下进行空气过滤实验,建立初步分析模型,分析了纤维直径和过滤性能间的关系。实验表明,纳米纤维的直径和过滤效率并不是正比关系,而是在某个纤径尺寸范围存在这一个最优值。对于PM10颗粒,纤维直径分布在400~600nm范围内的纳米纤维薄膜的过滤效果较好。分析模型的建立将促进纳米纤维薄膜空气过滤研究。Nanofibrous membranes of different nanofiber diameters are manufactured from electrospinning for the air filtration experiments,which are set in a mode of low wind velocity.A tentative model of experiment analysis is built up to analyze the relationship between filtration performance and nanofiber diameter.The experiments show that the filtration efficiency is not in direct proportion to the nanofiber diameter,which will be the best when the nanofiber diameter is in a special range.Better filtration performance for PM10 particles will be achieved when the nanofiber diameter is within the range between 400nm and 600nm.This experiment model will certainly further the researches on air filtration performance of nanofibrous membranes.国家自然科学基金资助项目(No.50675184);; 广东工业大学校青年基金资助项目(No.062042

The development of the monitor system of electronic control LPG engine

对电控LPG发动机监控系统的硬件配置、软件功能及实现和可视化操作界面进行了设计。台架试验证明本监控系统具有良好的数据采集、数据实时显示、参数在线调整、数据保存和打印、报警等功能和友好的人机交互式界面 ,可以实现对发动机的运行状况进行实时的监控The hardware configuration, soft function together with its implementation and interface of the monitor system of the electronic control LPG engine are designed in this paper. The test results demonstrate that the monitor system processes with perfect functions such as data acquiring, data displaying real time, parameter regulating online, data saving and printing, alarming and so on and friendly interface between the workman and system. So it can monitor the running state of engine real time