电磁驱动电容检测微机械陀螺的设计

介绍了一种电磁驱动电容检测微机械陀螺的结构和工作原理.该陀螺的突出优点在于驱动和检测采用了相互独立的折叠梁和振动质量,故驱动和检测间的耦合大大地减小.本文从理论上分析了折叠梁结构参数对振动模态频率的影响,并针对初步确定的结构尺寸,利用COVENTER WARE软件进行了静力学和动力学分析,对理论计算结果进行了验证.     

电磁驱动电容检测微机械陀螺的设计

介绍了一种电磁驱动电容检测微机械陀螺的结构和工作原理。该陀螺的突出优点在于驱动和检测采用了相互独立的折叠梁和振动质量 ,故驱动和检测间的耦合大大地减小。本文从理论上分析了折叠梁结构参数对振动模态频率的影响 ,并针对初步确定的结构尺寸 ,利用COVENTERWARE软件进行了静力学和动力学分析 ,对理论计算结果进行了验证     

无驱动结构硅微机械陀螺的信号处理

微机械陀螺因其微型化、低成本等优点,广泛用于微系统的姿态稳定与控制系统.研究了无驱动结构硅微机械陀螺的信号处理技术.通过硬件电路和软件算法及补偿技术,将旋转载体的滚动、俯仰和偏航的三维姿态角速度信号同时提取并输出.该陀螺可用于旋转载体的姿态测量和控制技术领域.     

微机械陀螺的闭环驱动电路的设计与实现

以北京微电子技术研究所自主研发的803微机械陀螺为研究对象,对陀螺的闭环驱动电路进行了分析和设计。闭环驱动电路实现方式主要有自激和锁相环驱动两种方式,对关键的C-V转换电路和AGC电路进行了设计实现。为以后微机械陀螺的驱动电路的研究设计提供依据。     

电容式z轴微机械陀螺的噪声抑制

将z轴微机械陀螺两个模态的机械噪声效应等效为各自在单位噪声力作用下的振动,根据陀螺的工作原理得到两个噪声力作用下陀螺敏感模态的机械输出噪声。建立了包含运放和电路板非理想因素在内的接口电路的噪声模型。结合机械噪声模型和接口电路模型噪声,建立了包括结构参数和电路最小检测电容量在内的陀螺的噪声等效输入角速度模型,为陀螺的设计优化提供了参考。分析了结构参数对陀螺等效输入角速度噪声影响,并采用两个参数不同的电容式z轴微机械陀螺进行了实验。结果表明,通过结构参数的调整,将电容式z轴微机械陀螺的输出噪声从414μV/Hz降低至235μV/Hz。     

旋转载体驱动的硅微机械陀螺误差研究

根据陀螺敏感元件的动力学方程,论证了导致陀螺误差的4个不稳定参数.其中,载体旋转角速度和气体阻尼系数不稳定是主要影响参数.实验结果表明,在低气体阻尼系数情况下,陀螺由于载体旋转角速度不稳定导致输出信号的相对误差高于30%.根据动力学方程建立的二元回归数学模型,得到的相对误差与实验结果相吻合,即理论论证和实验验证相一致.     

微机械结构的微静电驱动

本文讨论了微机械结构的微静电驱动技术的基本原理，同时结合硅微机械结构和材料特性，给出微静电驱动实现的考虑。     

静电驱动电容式微机械陀螺寄生Coriolis力的建模与分析

在静电驱动电容式微机械陀螺传感器结构的基础上,对寄生Coriolis力进行受力分析,建立了寄生Coriolis力的等效电学模型.比较分析了理想情况下微机械陀螺的等效电学模型以及包含寄生Coriolis力的等效电学模型,结果表明,对于静电驱动电容式微机械陀螺,寄生Coriolis力并不改变有用信号的频率及相位,对其峰峰值的衰减程度小于0.2‰.     

微机械音叉陀螺外围电路研究及仿真

介绍一种微机械音叉陀螺外围电路的基本结构及各组成部分的工作原理。针对机械敏感单元设计了陀螺的外围电路，通过系统分析，建立了数学模型，并利用Matlab对整个模型进行行为级仿真，验证所设计电路的可行性。仿真结果为电路的设计、调试提供了有利的分析方法和手段，具有一定指导意义。     

Design and fabrication of a micromachined resonant gyroscope

The micromachined gyroscope is rapidly gaining popularity as a rate sensor for application in areas such as automotive and aerospace systems, where low power consumption, high sensitivity, low temperature drift and good stability are prerequisites. In this paper, the overall design and fabrication process of a reactive ion-etched inertial resonant gyroscope based on the capacitive sensing principle is reported. The experimental results are also discussed.     

Design and noise analysis of a sigma-delta capacitive micromachined accelerometer

A single-loop fourth-order sigma-delta(ΣΔ) interface circuit for a closed-loop micromachined accelerometer is presented.Two additional electronic integrators are cascaded with the micromachined sensing element to form a fourth-order loop filter.The three main noise sources affecting the overall system resolution of aΣΔaccelerometer, mechanical noise,electronic noise and quantization noise,are analyzed in detail.Accurate mathematical formulas for electronic and quantization noise are established.The ASIC ...     

Design and noise analysis of a sigma-delta capacitive micromachined accelerometer

A single-loop fourth-order sigma-delta (∑△) interface circuit for a closed-loop micromachined accelerometer is presented.Two additional electronic integrators are cascaded with the micromachined sensing element to form a fourth-order loop filter.The three main noise sources affecting the overall system resolution of a ∑Δ accelerometer,mechanical noise,electronic noise and quantization noise,are analyzed in detail.Accurate mathematical formulas for electronic and quantization noise are established.The ASIC is fabricated in a 0.5 μm two-metal two-poly n-well CMOS process.The test results indicate that the mechanical noise and electronic noise are 1 μg(Hz) and 8 μV/(Hz)respectively,and the theoretical models of electronic and quantization noise agree well with the test and simulation results.     

一种基于倾斜悬臂梁的高性能硅微陀螺

This paper presents a novel structure for improving the stability and the mechanical noise of micromachined gyroscopes. Only one slanted cantilever is used for suspension in this gyroscope, so the asymmetry spring and the thermal stress, which most micromachined gyroscopes suffer from, are reduced. In order to reduce the mechanical noise, the proof masses are designed to be much larger than in most micromachined gyroscopes. The gyroscope chip is sealed at 0.001 Pa vacuum. A gyroscope sample and its read-out circuit are fabricated. The scale factor of this gyroscope is measured as 57.6 mV/（deg/sec） with a nonlinearity better than 0.12% in a measurement range of ±100 deg/sec. The short-term bias stability in 20 min is 60 deg/h.     

石英微机械振动陀螺振子的失效分析

微机械惯性器件是振动惯性技术和微电子技术相结合的产物，是振动惯性技术的延伸和发展，这就决定了该器件具有价格低、可靠性高、尺寸小和质量轻等突出特点。目前，它已成为经济发达国家研究的热点，也开始引起国内外惯性技术界的高度重视。     

High-performance micromachined gyroscope with a slanted suspension cantilever

This paper presents a novel structure for improving the stability and the mechanical noise of micromachined gyroscopes.Only one slanted cantilever is used for suspension in this gyroscope,so the asymmetry spring and the thermal stress,which most micromachined gyroscopes suffer from,are reduced.In order to reduce the mechanical noise,the proof masses are designed to be much larger than in most micromachined gyroscopes.The gyroscope chip is sealed at 0.00 1 Pa vacuum.A gyroscope sample and its read-out circuit are fabricated.The scale factor of this gyroscope is measured as 57.6 mV/(deg/sec) with a nonlinearity better than 0.12%in a measurement range of ±100 deg/sec.The short-term bias stability in 20 min is 60 deg/h.     

A silicon micromachined scanning thermal profiler with integratedelements for sensing and actuation

The thermal profiler is a scanning probe microscope with a miniature thermocouple (TC) at its tip which provides topographic and thermographic information by sensing heat conducted across a small air gap. The silicon micromachined thermal profilers (SMTPs) described in this paper are structurally comprised of a probe that can be longitudinally actuated by an integrated electrostatically driven suspension. A polysilicon-gold TC is located near the probe tip, which overhangs a glass substrate; a resistive heater is integrated with the base. An IC-compatible, 8-mask fabrication process has been developed and SMTPs with various types of frames and probes have been designed, fabricated, and thermally characterized. The maximum thermoelectric signal available from a 7-TC thermopile probe has been measured at 824 mV/W of input power to the heater, whereas from a simpler design it was 48 mV/W. Simple dithered and nondithered scans are presented to demonstrate the basic functionality of fabricated devices. The noise due to our test setup has been measured at ≈20 mK. For a 1 μm×0.5 μm tip and a 0.1 μm long air gap the spatial resolution and the device NETD have been theoretically estimated as ≈3.33 nm and ≈0.1 mK/√Hz, respectively     

Fibre gyroscope with passive quadrature detection

A novel configuration for the optical fibre gyroscope is described which utilises highly birefringent fibre and polarisation mode selection to achieve a stable ?/2 bias. By operating the system using a combination of both the unbiased and ?/2 biased Sagnac outputs, the possibility of wide dynamic range operation is realised.     

Fuzzy tuning PI control for initial levitation of micromachined electrostatically levitated gyroscope

A novel microgyroscope based on UV-LIGA technology is described, in which the wheel-like rotor is levitated and rotated by the electrostatic forces. A simple fuzzy logic scheme for online tuning of PI (proportional integral) controller parameters to improve system robustness of initial levitation is outlined. Experimental results indicate that, with fuzzy tuning, the overshoot is reduced to 17% compared with 27% of the conventional PI controller. The rise time for the two channels of the four is 3.6 ms and the settle time is nearly 25.6 ms, which shows a quick response time and good steady-state performance. From the experiment of 0.5 g pulse acceleration input, sensitivity along axial direction is 1 V g when it acts as an accelerometer.