基于隧道效应振动梁式陀螺仪自检电极设计

在微机电系统内建立自检系统是提高系统运行可靠性、安全性的重要手段之一。陀螺仪中的Coriolis力和其他惯性力存在一定的差别,即使在恒定的角速度输入下,Coriolis力也是一种动态变化的力。通过一对平板电极,其中,一个平板电极的边缘按照一定的函数变化,当陀螺仪的悬臂梁振动时,其平板间的静电力的变化能很好地模拟陀螺仪中的Coriolis力,有限元分析结果也表明:应用该方法完全能实现陀螺的自检和测试。     

线振动MEMS陀螺结构振动非线性特性研究

针对一种线振动微机电系统(MEMS)陀螺结构的振动非线性开展研究,利用理论方法推导、有限元仿真和扫频数据拟合得到了陀螺结构的非线性系数,根据达芬方程推导计算出非线性迟滞效应消失的临界激励以及对应的振幅阈值,为陀螺结构设计提供了理论指导.实验结果表明:非线性迟滞效应消失点和理论值相吻合.     

A method to simulate the vibrating characters of the resonator for resonant MEMS gyroscope

This paper proposes one study method of resonant MEMS gyroscope based on the circuit in order to solve problems such as long verification cycle and high cost of the MEMS gyroscope structure design. Firstly, on the basis of Euler–Bernoulli beam theory, this study establishes resonant beam vibration equation, obtains semi-Mathieu equation after normalization, namely parameter excitation characteristic equation of the frequency micro gyroscope, then deduces the characteristic equation in consideration of the damping condition, and uses the parameter perturbation method to study the output characteristic of gyroscope under ideal and damping states. Then, the analog circuit is innovatively used to obtain the characteristic equation of gyroscope under ideal and damping states, subsequently, the characteristic equation is normalized. It is realized that the dynamics equation is equivalent to the analog circuit. Finally, the experimental study is carried out, and experimental device for the frequency micro gyroscope harmonic oscillator parameter excitation characteristic is produced. Meanwhile, the analog circuit output waveform and frequency change correctness are verified by using the Runge–Kutta method and the parameter perturbation method, respectively. The experimental results show that the experiment device can be used to study the nonlinear vibration characteristics of the gyroscope.     

MEMS multi-vibrating ring gyroscope for space applications

Microsystem Technologies - This paper presents the design of a novel multi-ring vibratory gyroscope. The design incorporates two sets of rings, inner and outer, separated by a set of perforated...     

单轴系陀螺仪组测量系统

由ARM Cortex-M3单片机通过USB-HID接口和计算机(笔记本电脑)构成的上下位机模式的陀螺仪测试系统,实现了单轴系陀螺仪组的各种静态参数和动态参数测试.由上位计算机通过USB-HID端口发出各种控制状态,操纵下位机使得陀螺仪组模拟出实际的工作状态,完成了单轴系陀螺仪组的动态响应测试.     

A liquid rate gyroscope using electro-conjugate fluid

We propose a novel liquid rate gyroscope using an electro-conjugate fluid (ECF). The electro-conjugate fluid is a dielectric fluid that works as a smart fluid, generating a powerful jet flow (ECF jet) when subjected to a high DC voltage. In this study, we introduce this functional fluid into gyroscopes. Although the sensing principle for angular rate is based on that of a conventional gas rate sensor, the proposed gyroscope has a much higher sensitivity because the density of the liquid is generally higher than that of a gas. In addition, the gyroscope is small in size because the ECF jet is generated only with a pair of tiny electrodes. In other words, the pumping part of the proposed gyroscope does not need mechanical moving parts, resulting in an ECF gyroscope more suitable for micro-applications than a gas rate sensor, which requires a pumping mechanism inside. We fabricated a prototype of the liquid rate gyroscope (40 mm × 60 mm × t7 mm) and confirmed its characteristics by experiments. The experimental results confirm the effectiveness of the proposed liquid rate gyroscope. The prototype has a scale factor of ?29 mV/(°/s) with an applied voltage of 4.5 kV, which is 2.2 times more sensitive than the conventional gas rate gyroscope.     

A simple fabrication process for polysilicon side-drive micromotors

A simple fabrication process for rapid prototyping of side-drive polysilicon micromotors has been developed. This process uses three low-pressure chemical vapor depositions and three photolithography steps, and it enables fabrication of new micromotors and flange bearing designs. An important feature of this process is that the rotor, stator, and rotor/stator gap pattern definition is the first photolithography step and is performed over a flat surface. As a result, excellent linewidth resolution is possible for defining the rotor/stator gaps. Conventional wobble and salient-pole micromotors fabricated with this process have been operated for months after release, For wobble micromotors with 3-μm-thick rotor/stator polysilicon films, minimum operating voltages have been 25 V across 1.5-μm rotor/stator gaps; maximum operating speeds have been 1000 rpm. limited by the power supply. Corresponding salient-pole micromotors have had minimum operating voltages of 50 V; their maximum operating speeds have been near 5000 rpm     

A new hybrid robust control of MEMS gyroscope

To control microelectromechanical systems (MEMS) gyroscope axis, we propose and investigate a new robust sliding mode controller (NRSMC). The sliding surface in the phase space converges to the equilibrium point within a finite period from any initial state. However, the main drawback of this control system is the chattering phenomenon, which is undesirable for the MEMS system. To solve this problem, we suggest a novel hybrid control system which improves trajectory tracking and eliminates the chattering. The dynamic stability of NRSMC against external disturbances is proved by applying the Lyapunov theory. The effectiveness of the proposed control method is verified by numerical simulation with a random noise applied to demonstrate the robustness of the proposed control system.

     

耐高温多晶硅应变计

介绍了一种适用于特殊环境进行高温测量的多晶硅应变计的原理、设计、制作工艺及粘贴方法。它的特点是耐高温 (可用在温度达 2 5 0℃的环境中 )、体积小、安装方便。该种应变计已用于检测电站锅炉焊缝的牢固程度 ,在实际应用中性能较好     

High aspect-ratio combined poly and single-crystal silicon (HARPSS)MEMS technology

This paper presents a single-wafer high aspect-ratio micromachining technology capable of simultaneously producing tens to hundreds of micrometers thick electrically isolated poly and single-crystal silicon microstructures. High aspect-ratio polysilicon structures are created by refilling hundreds of micrometers deep trenches with polysilicon deposited over a sacrificial oxide layer. Thick single-crystal silicon structures are released from the substrate through the front side of the wafer by means of a combined directional and isotropic silicon dry etch and are protected on the sides by refilled trenches. This process is capable of producing electrically isolated polysilicon and silicon electrodes as tall as the main body structure with various size capacitive air gaps ranging from submicrometer to tens of micrometers. Using bent-beam strain sensors, residual stress in 80-μm-thick 4-μm-wide trench-refilled vertical polysilicon beams fabricated in this technology has been measured to be virtually zero. 300-μm-long 80-μm-thick polysilicon clamped-clamped beam micromechanical resonators have shown quality factors as high as 85 000 in vacuum. The all-silicon feature of this technology improves long-term stability and temperature sensitivity, while fabrication of large-area vertical pickoff electrodes with submicrometer gap spacing will increase the sensitivity of micro-electromechanical devices by orders of magnitude     

A rate gyroscope based on interaction of sonic waves

A new form of rate gyroscope based on interaction between standing sonic waves in solid media is described. One form of the device, using a solid, ring-shaped medium, is analyzed in order to establish the relationship between the modes of the two waves that must exist to produce sensitivity to angular rate. In addition, the analysis establishes estimates for the angular-rate sensitivity in terms of the basic instrument parameters. The theoretical feasibility of the proposed instrument has been confirmed by experiments conducted on a simple laboratory model. The results indicate that strain-induced and mass unbalance cross-coupling between the driving and sensing waves can produce uncertainty in the instrument output signal. These unwanted cross-coupling effects are the practical limitation on the instrument performance at the present time. Methods for their reduction and cancellation are discussed for the ring-shaped transducer. The problem of unwanted cross-coupling seems to be present in sonic gyroscopes, in general, and is not unique to solid media alone. In particular, some preliminary experiments with fluid devices show them to have similar cross-coupling problems. In conclusion, the major advantages over conventional rate gyroscopes of instruments based on interaction of sonic waves appear to be: low power consumption, long life, (potentially) high reliability, ruggedness, and low cost. These advantages must be weighed against the primary disadvantage of the lower precision that is available at the present state of the development.     

A MEMS piezoelectric solid disk gyroscope with improved sensitivity

Microsystem Technologies - This paper introduces a MEMS piezoelectric solid disk gyroscope. The gyroscope operates in an in-plane elliptic bulk acoustic wave mode with a frequency of...     

一种新的陀螺振子及工作方式的研究

本文提出了一种新形式的陀螺振子结构,介绍了其工作原理。当陀螺振子在驱动模态谐振时,检测与驱动正交振动位置的振动情况,推导出了两模态振动公式。利用有限元软件建模,对新振子能否满足驱动与检测模态频率相等的灵敏度要求进行仿真验证。     

MEMS-SAW陀螺仪研究

采用耦合模(COM)理论对声表面波(SAW)谐振器进行数字模拟,并采用梅森(Mason)正交场模型对陀螺仪和传感器进行模拟设计,最后对SAW谐振器和SAW传感器进行实验评价.这种陀螺仪具有额外的能力,可以作为无线陀螺仪和集成在SAW加速度传感器上.     

A multi-objective vibrating particle system algorithm for data clustering

Pattern Analysis and Applications - Clustering is an important data mining technique described as unsupervised learning. Till date, many single-objective clustering algorithms have been developed...     

基于MEMS陀螺仪的微惯性测量系统的实现

微机电(MEMS)惯性传感器应用日益广泛,本文给出了一种基于新型MEMS陀螺仪的微惯性测量系统的实现.系统采用了ANALOG DIVICES公司的AIDS16255陀螺仪,其精度较高,并增加了校准功能,能够在内部对敏感度和偏差因子进行补偿.系统具有体积小、重量轻、可扩展性好等特点.本文给出了系统的原理图和软件流程的关键内容.     

A new adaptive fractional sliding mode control of a MEMS gyroscope

Microsystem Technologies - The Micro-Electro-Mechanical System (MEMS) gyroscope is a well-known device, which has been widely used in medicine due to its small size. In this study, a new adaptive...     

Magnetic microactuation of polysilicon flexure structures

A microactuator technology that combines magnetic thin films with polysilicon flexural structures is described. Devices are constructed in a batch-fabrication process that combines electroplating with conventional lithography, materials, and equipment. A microactuator consisting of a 400×(47-40)×7 μm³ rectangular plate of NiFe attached to a 400×(0.9-1.4)×2.25 μm³ polysilicon cantilever beam has been displaced over 1.2 mm, rotated over 180°, and actuated with over 0.185 nNm of torque. The microactuator is capable of motion both in and out of the wafer plane and has been operated in a conductive fluid environment. Theoretical expressions for the displacement and torque are developed and compared to experimental results     

Thermal conductivity of doped polysilicon layers

The thermal conductivities of doped polysilicon layers depend on grain size and on the concentration and type of dopant atoms. Previous studies showed that layer processing conditions strongly influence the thermal conductivity, but the effects of grain size and dopant concentration were not investigated in detail. The current study provides thermal conductivity measurements for low-pressure chemical-vapor deposition (LPCVD) polysilicon layers of thickness near 1 μm doped with boron and phosphorus at concentrations between 2.0×10¹⁸ cm^-3 and 4.1×10¹⁹ cm^-3 for temperatures from 20 K to 320 K. The data show strongly reduced thermal conductivity values at all temperatures compared to similarly doped single-crystal silicon layers, which indicates that grain boundary scattering dominates the thermal resistance. A thermal conductivity model based on the Boltzmann transport equation reveals that phonon transmission through the grains is high, which accounts for the large phonon mean free paths at low temperatures. Algebraic expressions relating thermal conductivity to grain size and dopant concentration are provided for room temperature. The present results are important for the design of MEMS devices in which heat transfer in polysilicon is important     

Controlled stepwise motion in polysilicon microstructures

This paper presents a polysilicon slider and a rotor capable of stepwise motion. These devices were fabricated on a silicon wafer with surface micromachine technology. The proportional relation between the velocity of motion and the frequency of the applied pulse was experimentally confirmed. The peak value of the applied pulse determines the step length. The step values observed were in the range of 10-30 nm for a bushing height of 1.0 μm and of 40-80 nm for a bushing height of 2.0 μm depending on the peak voltage of the applied pulse