新型摇摆质量微陀螺的设计与制作(英文)

首先介绍了两种结构完全对称的高灵敏度的摇摆质量陀螺.设计并制作了一种对角驱动的新型摇摆质量微陀螺.利用硅的各向异性湿法腐蚀等MEMS体加工技术,简化了该微陀螺的制作工艺.该微结构的对称性、一致性和加工精度有很大改善,尤其是振动梁、激励部件和敏感部件等关键部件.详细阐述了该微陀螺的工作原理和结构设计,完成了微陀螺关键部件的制作和样机组装.利用NF公司的FRA 5087频率响应分析仪测试了样机大气下的振动模态,其中驱动频率为5.563 2 kHz,检测频率为5.553 4 kHz,频差为9.8 Hz,小于0.2%.利用频谱分析的方法测试了样机的哥氏力.测试结果表明这种摇摆质量微陀螺的设计与制作方法是可行的.     

Design and Analysis of a Tri-Axis Gyroscope Micromachined by Surface Fabrication

This paper presents an innovative microgyroscope design. Solely by planar fabrication and wet etching, the proposed microgyroscope is capable to detect three-axis angular rates. The induced motion of individual seismic mass modules are designed to respond in the directions orthogonal to each other in order to decouple the obtained measures. In our work, three pairs of high-resolution differential capacitors with signal processing circuits are employed to measure the angular velocity components in three axes. On the other hand, the drive electrode comb is used to constantly vibrate the outer-ring in tangential direction by sinusoidal voltage. The signal bandwidth about the principle axis is increased by distributed translational proof masses, placed 90$^circ$ apart orderly around a circle. Each individual translational proof mass is designed to move in radial direction so that superior mode matching (i.e., resonance mode) can be easily, to some extent, achieved. The planar suspension flexures are particularly designed in geometry to resist acceleration in drive mode but increase the stroke of tilting angular displacement of the outer-ring such that the resolution of detected angular rate for the corresponding sense mode is upgraded. By considering the complicated geometry of the suspension flexures, finite-element method (FEM) is employed to examine the potential maximum induced mechanical stress. The dynamic equations of the proposed gyroscope are established are well so that the embedded gyroscopic effects are unveiled. More importantly, the efficacy of the drive and sense circuits modules is verified by commercial softwares Hspice and Multisim. By intensive computer simulations and preliminary experimental studies, the resolution, bandwidth and sensitivity of the tri-axis gyroscope are expected to be fairly enhanced if a certain degree of tradeoff is preset.      

微静电陀螺仪的结构设计与工艺实现

为了探索微机械陀螺突破精度极限的新途径,设计了一种基于环形转子、体硅加工工艺、转子5自由度悬浮的硅微静电陀螺仪.采用玻璃-硅-玻璃键合的三明治式微陀螺结构,提出了包括双边光刻、反应离子刻蚀(RIE)、电感耦合等离子体(ICP)刻蚀、玻-硅静电键合、硅片减薄、多层金属溅射等关键工艺的加工路线.在工艺设计中采用铝牺牲层对转子进行约束,在第2次玻-硅键合后再通过湿法去除牺牲层,以得到可自由活动的转子.基于提出的体硅工艺路线,成功加工出了微陀螺敏感结构,并完成了转子5自由度悬浮和加转实验,测试结果表明大气环境下转子转速可达73.3 r/min.     

陀螺稳定控制系统设计与仿真

针对现代伺服系统中,必须同时解决伺服跟踪和隔离载体扰动的问题,采用陀螺作为速度敏 感元件,根据陀螺稳定系统的组成特点,利用频域法设计出稳定控制系统,并对设计的系统进行仿真。从仿真结果可以看出,设计的系统满足主要的技术指标。     

电容式硅微机械陀螺仪结构设计及仿真

通过对微机械陀螺的调研分析,提出了一种新型微机械陀螺仪,并对陀螺进行了结构设计.该结构采用静电梳齿驱动、栅结构电容检测,使陀螺具有较高灵敏度.驱动模态和检测模态均为滑膜阻尼,能够实现较高的Q值,且具有一定的解耦特性.文中通过仿真分析得到了结构的各阶频率,使陀螺驱动模态和检测模态固有频率匹配,验证了结构的合理性.结合现有...     

三自由度水平轴硅微机械陀螺结构设计与仿真

为了兼顾测量带宽和灵敏度的要求，提出了一种三自由度水平轴硅微陀螺系统，此系统由3个质量块组成。质量块2与质量块3组合后与质量块1构成了一个二自由度驱动方向的谐振器，再利用该谐振器进行动力学放大，得到非谐振状态下的大驱动振幅．陀螺驱动频率响应曲线有两个谐振尖峰，在两峰值之间存在一个较平坦的区域，当陀螺驱动工作在频率响应曲线的平坦区域时，机械增益虽然比工作在谐振尖峰处小，但机械增益受频率变化的影响减小，驱动频率的工作带宽增加，使得对驱动的控制要求相对宽松．文中给出了动力学放大原理及所设计的陀螺结构的理论计算和仿真值．     

一种全对称微机械陀螺的双级解耦机构特性

为了实现微机械陀螺的频率匹配和双级解耦,提出了一种全对称双级解耦结构体硅微机械陀螺.该陀螺结构完全对称,容易实现驱动和检测模态谐振频率的匹配,提高系统灵敏度.驱动和检测方向的主要阻尼均为滑膜阻尼,在常压下工作也可以获得较高的品质因子,避免了器件的真空封装.利用4组十字折梁,实现了结构的双级解耦.仿真结果表明,模态之间的耦合系数小于0.17%.采用体硅微机械加工技术制作了样品,关键工艺有硅-玻璃阳极键合和DRIE技术.基于计算机图像技术对微机械陀螺进行了测试,验证了陀螺的解耦功能,在常压条件下测得该陀螺的品质因子为195,灵敏度为8.031 mV/（（°）.s^-1）.     

具有栅结构与静电梳齿驱动的电容式微机械陀螺的仿真、设计与测试

电容式陀螺仪是一种振动式陀螺仪,由于加工的特殊性使其具有了传统的陀螺无法比拟的优点,从而拓宽了其应用领域.为了提高陀螺仪的检测精度,本文提出了一种静电梳齿驱动、栅结构的电容式检测的微机械陀螺仪的设计方法,并分析了其工作原理.运用ANSYS软件对陀螺结构进行了仿真和模态分析,仿真结果与理论计算结果相接近.所设计的陀螺结构采用体硅标准工艺方法进行了设计,并对其进行了流片加工和封装,最终得到了电容式微机械陀螺仪.实验测试的结果表明,陀螺驱动模态的固有频率为4.06kHz,灵敏度为0.027 9 v/((°)s-1).     

Convective instability of a free-convection vortex

The stability of free-convection vortex formations obtained in the laboratory is compared with natural tropical cyclones.Nomenclature r radius - density of air - P pressure drop between the center of a vortex and its edge - latitude of the location of a natural tropical cyclone Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 58, No. 3, pp. 416–419, March, 1990.     

微机械振动式陀螺仪灵敏度分析

微机械振动式陀螺仪在飞机、轮船的惯性导航系统中有重要应用。介绍微机械振动式陀螺仪的工作原理。给出其运动微分方程。推导谐振幅值相对于转动角速度的灵敏度表达式。分析表明：谐振状态下哥氏力与静电力成正比,与驱动模态频率成反比。减小检测质量块的刚度可提高陀螺仪的灵敏度。     

某陀螺地平仪自检测系统设计

针对某陀螺地平仪平均无故障时间较短,故障率高,且外部检测困难的问题,设计了某陀螺地平仪的机内自检测系统.分析了某陀螺地平仪的功能结构及其故障模式,提出了其自检测方案.采用ADUC 812单片机、数码管等,设计了集成化、嵌入式的自检测系统硬件电路,并利用汇编语言编程实现了机内自检测软件.通过试验验证了系统的有效性.     

Frequency Response Characteristics of a Rate Gyroscope Using a Microsyn

The method of obtaining a frequency response of a rate gyroscope, as described in this article, is applicable to any gyroscope which is equipped with a variable reluctance transformer (microsyn). The damping ratio of the gimbal system can be obtained under any environmental condition without mechanical rotation of the gyroscope and without breaking the electrical connections to it. The microsyn is electrically excited to exert upon the gimbal a sinusoidally varying-in-time torque of constant amplitude and of controllable frequency, and at the same time is used to indicate the resulting displacement of the gimbal.     

X射线光刻掩模加工过程中的形变研究

对以SiNx为衬基的X射线光刻掩模在背面刻蚀过程中的形变进行数值仿真,研究了Si片和衬基的各种参数对掩模最大平面内形变和非平面形变的影响.结果表明,参数的变化明显影响最大非平面形变量.当Si片的厚度和直径增大,衬基的厚度和初始应力减小时,最大平面内形变与非平面形变减小,而衬基的材料对两者的影响不明显.     

Design,Fabrication, Characterization and Simulation of PIP-SiC/SiC Composites

Continuous SiC fiber reinforced SiC matrix composites (SiC/SiC) have been studied and developed for high temperature and fusion applications. Polymer impregnation and pyrolysis (PIP) is a conventional technique for fabricating SiC/SiC composites. In this research, KD-1 SiC fibers were employed as reinforcements, a series of coatings such as pyrocarbon (PyC), SiC and carbon nanotubes (CNTs) were synthesized as interphases, PCS and LPVCS were used as precursors and SiC/SiC composites were prepared via the PIP method. The mechanical properties of the SiC/SiC composites were characterized. Relationship between the interphase shear strength and the fracture toughness of the composites was established. X-ray tomographic scans of the SiC/SiC composites were performed and the closed porosities of the composites were calculated. The compatibility of the SiC/SiC composites with liquid LiPb at 800 °C and 1000 °C was investigated. High-resolution synchrotron X-ray tomography was applied to the SiC/SiC composite and digital volume correlation was employed for Hertzian indentation testing of the SiC/SiC composite. A Cellular Automata integrated with Finite Elements (CAFE) method was developed to account for the effect of microstructure on the fracture behavior of the SiC/SiC composite.     

氮化硅-铼嬗变模拟靶材的制造和性能研究

采用无压烧结的方法(在1550℃保温3小时)添加5wt.％MgO,5wt.％Y2Oa和不同含量的Re制造出了Si3N4-Re嬗变模拟靶材.研究了Re含量的不同对嬗变靶材致密度和抗弯强度的影响,并通过物相分析,显微组织和断口形貌观察对相关机理进行了分析.     

Symmetric and Asymmetric Convective Oscillations in a Multilayer System

The nonlinear development of oscillatory instability under the joint action of buoyant and thermocapillary effects in a multilayer system, is investigated. The nonlinear convective regimes are studied by the finite difference method. The rigid heat-insulated lateral walls, are considered. Transitions between the motions with different spatial structures are investigated. Specific types of flows, symmetric and asymmetric oscillations, have been found. It is shown that the oscillatory motion takes place in an interval of the Grashof number values bounded both from below—by the mechanical equilibrium, and from above—by the steady state.     

Convective coherent structures in a Hele-Shaw cell

Convective processes related to the onset of chaotic flows in a Hele-Shaw cell have been theoretically and experimentally studied. The properties of various modifications of a specific pulsation regime, in which certain characteristics exhibit chaotization with increasing Rayleigh number while the flow pattern remains statistically reproducible and retains a regular character, have been determined for the cavities with various ratios of the dimensions of wide sides. An analogy is established that allows pulsating vortices in the flow to be treated as simple coherent structures of a convective nature.