WO2018188382A1 - 基于谐振器同步振荡的频率检测方法及倾角传感器 - Google Patents

基于谐振器同步振荡的频率检测方法及倾角传感器 Download PDF

Info

Publication number
WO2018188382A1
WO2018188382A1 PCT/CN2017/120360 CN2017120360W WO2018188382A1 WO 2018188382 A1 WO2018188382 A1 WO 2018188382A1 CN 2017120360 W CN2017120360 W CN 2017120360W WO 2018188382 A1 WO2018188382 A1 WO 2018188382A1
Authority
WO
WIPO (PCT)
Prior art keywords
synchronous
detecting
oscillation
capacitor
tilt sensor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2017/120360
Other languages
English (en)
French (fr)
Inventor
韦学勇
翁寅生
王曙东
浦东
蒋庄德
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xian Jiaotong University
Original Assignee
Xian Jiaotong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xian Jiaotong University filed Critical Xian Jiaotong University
Priority to US16/465,576 priority Critical patent/US20190293421A1/en
Publication of WO2018188382A1 publication Critical patent/WO2018188382A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/24—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/30—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring angles or tapers; for testing the alignment of axes
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C9/00—Measuring inclination, e.g. by clinometers, by levels
    • G01C9/02—Details
    • G01C9/06—Electric or photoelectric indication or reading means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/125—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by capacitive pick-up
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/18—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration in two or more dimensions

Definitions

  • the invention relates to the technical field of inclination sensors, in particular to a frequency detection method based on synchronous oscillation of a resonator and an inclination sensor thereof.
  • the importance of the tilt sensor, especially the high-precision full-range tilt sensor, is self-evident.
  • Premier Li Keqiang put forward the "Made in China 2025" grand plan, clarified the strategic task of building a manufacturing power, and pointed out nine strategic priorities, including high-end CNC machine tools and robots, aerospace equipment, and high-performance medical equipment.
  • the field is closely related to sensors, especially high-precision tilt sensors. It can be said that the realization of high-precision full-range tilt sensor is one of the important conditions for building and manufacturing a strong country.
  • the resonant MEMS tilt sensor As a high-precision sensor, the resonant MEMS tilt sensor has been favored and valued by researchers all over the world. It is generally composed of a sensitive component, a resonant component, and a signal processing circuit.
  • the sensitive component of the sensor is used to sense the in-plane gravity acceleration.
  • the gravity signal is converted into a frequency signal by the resonant component, and then processed by the signal processing circuit to invert the angle value.
  • the measurement accuracy is affected by the topology of the sensor's sensitive components, the processing technology, the driving and detection principle, and the oscillator frequency stability.
  • the object of the present invention is to provide a frequency detection method based on synchronous oscillation of a resonator and a tilt angle sensor thereof, which realize full-scale and ultra-high-precision measurement of the plane in-tilt angle.
  • a MEMS full-scale tilt sensor based on synchronous oscillation frequency detection comprising a mass for sensing gravitational acceleration, a magnifying beam, a detecting element and a synchronizing element arranged around the mass; the gravitational acceleration that the mass will feel The conversion to pressure or tension is applied to the magnifying beam, which is transmitted through the magnifying beam and amplified to be applied to the detecting element, changing the stiffness and natural frequency of the three detecting elements.
  • the main body of the detecting component is a detecting harmonic oscillator, and two sides of the detecting harmonic oscillator are respectively arranged with a first capacitive flat plate and a second capacitive flat plate, and two ends of the detecting harmonic oscillator are respectively connected to the amplifying beam and the first fixed end, and the first fixed a first metal electrode layer is sputtered on the end; a third capacitor plate is disposed on the opposite side of the first capacitor plate, the first capacitor plate and the third capacitor plate constitute a first plate capacitor, and the third capacitor plate is fixed to the second On the fixed end, a second metal electrode layer is sputtered on the second fixed end.
  • the main body of the synchronizing element is a synchronous resonator, and a fourth capacitive flat plate and a fifth capacitive flat plate are respectively arranged on both sides, and a third fixed end and a fifth fixed end are respectively arranged on the top and the bottom, and the third fixed end is sputtered on the third fixed end.
  • a three-metal electrode layer; a sixth capacitor plate is disposed on the opposite side of the fourth capacitor plate, the fourth capacitor plate and the sixth capacitor plate form a second plate capacitor, and the sixth capacitor plate is fixed on the fourth fixed end, and the fourth A second metal electrode layer is sputtered on the fixed end, and the fifth capacitor plate is opposite to the second capacitor plate and constitutes a third plate capacitor.
  • the oscillating circuit with automatic gain control includes a feedthrough current canceling circuit, an amplifier, a band pass filter, a phase shift circuit, a comparator and an amplitude adjustment circuit, which are sequentially connected, wherein the feedthrough current cancel circuit and the first metal electrode layer or The three metal electrode layers are connected, and the amplitude adjusting circuit is connected to the second metal electrode layer or the fourth metal electrode layer.
  • the sensor comprises a single crystal silicon substrate, an insulating layer grown on the single crystal silicon substrate, and a single crystal silicon structural layer grown on the insulating layer, the mass, the amplifying beam, the detecting element and the synchronizing element are all located in the single crystal silicon On the structural layer, the single crystal silicon substrate plays a supporting role, ensuring that the single crystal silicon structural layer is suspended and free to vibrate.
  • the amplifying beam, the detecting element and the synchronizing element are integrated and radially distributed uniformly around the mass.
  • the capacitance plate has a pitch of 0.1 ⁇ m to 2 ⁇ m.
  • An angle measuring method for a MEMS full-scale tilt sensor based on synchronous oscillation frequency detection in which a mass generates a pressure or a tensile force on an enlarged beam while receiving an in-plane gravity acceleration, and the force is amplified by an amplification beam and applied to the detecting element.
  • a mass generates a pressure or a tensile force on an enlarged beam while receiving an in-plane gravity acceleration
  • the force is amplified by an amplification beam and applied to the detecting element.
  • Synchronous vibration of the two oscillators is realized by electrostatic coupling of the third plate capacitor to greatly reduce the noise floor of the oscillator and improve the frequency stability of the detecting element; when the self-oscillation frequency of the first oscillation circuit and the second oscillation circuit When it is 1:1, 1:3 or 1:9, synchronous amplification of the frequency change of the detecting element is realized, and the detection sensitivity of the detecting element is improved.
  • the present invention is provided with a synchronizing element which is electrostatically coupled to the detecting element while providing the detecting element.
  • a synchronizing element which is electrostatically coupled to the detecting element while providing the detecting element.
  • the tilt angle of the entire device can be calculated.
  • the silicon microresonator-based oscillator has stable frequency, low noise and easy integration.
  • the tilt sensor designed according to this has small volume, high sensitivity and large measuring range.
  • the frequency detection method based on synchronous oscillation of the resonator can achieve lower noise floor. And higher frequency stability for ultra-precise tilt measurement.
  • Figure 1 is a schematic view of the structure of the present invention.
  • FIG. 2 is a plan view of a single crystal silicon structural layer of the present invention.
  • Figure 3 is a schematic diagram of the measuring circuit of the present invention.
  • Figure 4 is a schematic diagram of an improved measurement circuit of the present invention.
  • a MEMS full-scale tilt sensor based on synchronous oscillation frequency detection comprising a single crystal silicon substrate 01 having a thickness ranging from 400 um to 1000 um, a silicon oxide insulating layer 02 grown on a single crystal silicon substrate 01, and a thickness range of growth For 2-3 um, the silicon oxide insulating layer 02 is provided with a single crystal silicon structural layer 03 having a thickness ranging from 10 to 25 um.
  • the single crystal silicon structural layer 03 is a core portion of the sensor, and is composed of four modules of a mass 1, an amplifying beam 2, a detecting element 3, and a synchronizing element 4.
  • the function of the mass 1 is to feel the in-plane gravitational acceleration and convert the acceleration into a pressure or tension applied to the magnifying beam 2.
  • the magnifying beam 2, the detecting element 3 and the synchronizing element 4 are integrally formed and radially distributed uniformly around the hexagonal mass 1 .
  • the magnifying beam 2, the detecting element 3 and the synchronizing element 4 are integrally formed in six.
  • the hexagonal mass 1 is suspended and supported only by the magnifying beam 2, and the other end of the magnifying beam 2 is connected to the detecting element 3.
  • the magnifying beam 2 comprises an input beam 2-1, a lever 2-2, a fulcrum 2-3 and an output beam 2-4, and the input beam 2-1 is connected to the hexagonal mass 1 and serves as an input end of the force.
  • the magnification of the lever 2-2 and the fulcrum 2-3 is applied to the output beam 2-4, the other end of the output beam 2-4 is connected to the detecting harmonic oscillator 3-1, and the thinner portion of the fulcrum 2-3 is suspended (the fulcrum is finer)
  • the part refers to the portion where the fulcrum 2-3 is connected to the lever 2-2), functions as a fulcrum, and the thicker portion is in contact with the single crystal silicon substrate 01, and functions as a fixing point, that is, a fixed point of the fulcrum 2-3.
  • the input beam 2-1 is a pair, respectively connected to the mass 6 and located at one end of one side of the mass, and the lever 2-2 is respectively extended from the input beam toward the middle.
  • the output beams 2-4 are also a pair, connected to respective respective levers 2-2 and fulcrums 2-3. That is, one end of the lever 2-3 is connected to the input beam 2-1, and the other end is connected to the output beam 2-4.
  • the main body of the detecting component 3 is a detecting resonator 3-1, and a first capacitor flat plate 3-2 and a second capacitor flat plate 3-3 are disposed on both sides thereof, and a first fixed end 3-5 is disposed at the top, A first metal electrode layer 3-4 is sputtered on a fixed end 3-5, and a third capacitor flat plate 3-8 is disposed on a side of the first capacitor flat plate 3-2, and the first capacitor plate 3-2 and the third The capacitor plate 3-8 constitutes a first plate capacitor, the third capacitor plate 3-8 is fixed to the second fixed end 3-7, and the second fixed electrode 3-6 is sputtered with a second metal electrode layer 3-6.
  • the synchronizing element 4 is similar in structure to the detecting element 3.
  • the main body is a synchronous resonator 4-1, and a fourth capacitive flat plate 4-2 and a fifth capacitive flat plate 4-3 are provided on both sides.
  • a third fixed end 4-5 is disposed, a third metal electrode layer 4-4 is sputtered on the third fixed end 4-5, and a sixth capacitive flat plate 4-8 is disposed on the opposite side of the fourth capacitive flat plate 4-2.
  • the fourth capacitor plate 4-2 and the sixth capacitor plate 4-8 constitute a second plate capacitor, the sixth capacitor plate 4-8 is fixed on the fourth fixed end 4-7, and the fourth fixed end 4-7 is splashed.
  • the fourth metal electrode layer 4-6 is incident, and the fifth capacitor plate 4-3 is opposite to the second capacitor plate 3-3 and constitutes a third plate capacitor, and the synchronization signal is transmitted therefrom, and the bottom of the synchronous resonator 4-1 is provided.
  • the five fixed ends 4-9, the thinner portions of the fifth fixed end 4-9 are connected (ie, the fifth fixed end 4-9 is connected to the synchronous resonator 4-1 through a thinner beam) and are suspended, relatively thick
  • the part is connected to the single crystal silicon base 01 and functions as a fixing.
  • the first to fourth fixed ends are all square, and the side length ranges from 180 ⁇ m to 600 ⁇ m, and the fifth fixed end is polygonal.
  • the metal electrode plates are squares slightly smaller than the fixed end, and the side length ranges from 150 ⁇ m - 250 ⁇ m, the length of the capacitor plate ranges from 50 ⁇ m to 200 ⁇ m, and the spacing of two corresponding capacitor plates is 0.1 ⁇ m - 2 ⁇ m.
  • a typical resonator for tilt measurement is a double-ended fixed resonant tuning fork, but for the present invention, any suitable beam resonator or bulk modal resonator can be employed.
  • the resonant element 3 and the synchronizing element 4 are respectively placed in a first oscillating circuit and a second oscillating circuit having automatic gain control, and the oscillating circuit includes a feedthrough current canceling circuit 5-1, an amplifier 5-2, Band pass filter 5-3, phase shifting circuit 5-4, comparator 5-5, and amplitude adjusting circuit 5-6, under specific circuit parameters, the resonant element 3 and the synchronizing element 4 are respectively formed from the oscillating circuit
  • the oscillation is excited, and the oscillation frequency is the natural frequency of the resonator, which can be read by the frequency measuring device 5-7.
  • phase-lock loop PLL
  • the phase-locked loop includes a Phase Discriminator (PD) 5-8, a Loop Filter (LF), and a Voltage Controlled Oscillator (VCO) 5-10.
  • the bandpass filter with high Q value can replace the bandpass filter 5-3, which makes the noise floor smaller and the frequency stability higher.
  • the working principle of the invention is:
  • the mass 1 When the mass 1 receives the in-plane gravitational acceleration, it simultaneously generates pressure or tension on the three pairs of the magnifying beams 2, and the force is transmitted through the magnifying beam 2 and amplified and applied to the detecting element 3, changing the natural frequency of the detecting harmonic oscillator 3-1. Since three detecting harmonic oscillators and three synchronous resonant devices are respectively placed in three synchronous oscillating circuits with automatic gain control, synchronous self-oscillation is formed, and the oscillation frequency and its variation of three synchronous self-oscillation circuits are detected. , you can reverse the tilt value of the entire device.
  • the hexagonal mass 1, the magnifying beam 2, the detecting element 3 and the first oscillating circuit can constitute a complete tilting test system, but due to the noise existing in the silicon micro-oscillator and the external environment The drift caused by the test is limited (see patent CN 105737811 A).
  • the synchronizing element 4 When the synchronizing element 4 is operated, its self-oscillation will also be generated in the closed-loop circuit at the natural frequency of the synchronous resonator 4-1, and since the synchronizing element 4 and the detecting element 3 are electrostatically coupled, the two will form a synchronous self-oscillation.
  • the synchronization effect is best, and the oscillator frequency composed of the detecting harmonic oscillator 3-1 is at this time.
  • the stability will be greatly improved, and the signal-to-noise ratio of the frequency signal read by the frequency measuring device 5-7 will also be greatly improved, thereby improving the test accuracy of the tilt sensor.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Micromachines (AREA)
  • Gyroscopes (AREA)

Abstract

一种基于谐振器同步振荡的频率检测方法及倾角传感器，包括检测元件(3)和同步元件(4)，分别置于第一振荡电路和第二振荡电路中并形成两个自激振荡器，检测元件(3)和同步元件(4)通过平板电容静电耦合，微弱的同步电流得以穿过，影响并降低检测元件(3)振荡器的相位噪声，大幅提升其频率稳定性，其固有频率可通过频率计数器读取。三个检测元件(3)分别通过放大梁(2)围绕一个六边形质量块(1)均匀分布，质量块(1)用于感受重力加速度并施加拉压力于放大梁(2)上，放大梁(2)放大并传递该力于检测元件(3)，改变其自激振荡频率，形成同步自激振荡，通过检测三个同步自激振荡电路的振荡频率及其变化，反演出整个器件所受加速度大小及方向。

Description

一种基于谐振器同步振荡的频率检测方法及其倾角传感器 【技术领域】
本发明涉及倾角传感器技术领域，特别涉及一种基于谐振器同步振荡的频率检测方法及其倾角传感器。
【背景技术】
倾角传感器，尤其是高精度全量程倾角传感器的重要性是不言而喻的。2015年，国务院总理李克强提出了“中国制造2025”宏大计划，明确了建设制造强国的战略任务，指出了9项战略重点，其中高档数控机床和机器人、航空航天装备、高性能医疗器械这三个领域都与传感器，尤其是高精度倾角传感器密切相关，可以说，实现高精度全量程倾角传感器是建设制造强国的重要条件之一。
谐振式MEMS倾角传感器作为一种高精度传感器一直受到各国研究者的青睐和重视。其一般由敏感元件、谐振元件及信号处理电路组成，传感器的敏感元件被用以感受面内重力加速度，该重力信号由谐振元件转化为频率信号，再由信号处理电路处理并反演角度值。对于谐振式倾角传感器，其测量精度受到传感器敏感元件的拓扑结构、加工工艺、驱动与检测原理以及振荡器频率稳定性等因素的影响。在绝大数情况下，微弱的重力加速度变化引起的谐振频率变化淹没在闭环振荡器的本底噪声中，从而导致无法精确的测量微重力变化。因此，近十年来各国研究者在努力提高加速度传感器标度因数的同时，也在不断探索新的方法来降低振荡器的本底噪声。
2013年，本专利申请人及其剑桥大学的合作者分别在不同拓扑结构下发现了模态耦合和非线性幅值饱和效应对于提高硅微振荡器频率稳定性的作用，同年，本专利申请人的合作者设计了通过静电力相互作用的两个微音叉梁振荡器，并首次观察到了MEMS中的同步现象，同时发现了同步引起振荡器频率稳定性提高、本底噪声降低的现象。
基于现有公开专利CN 105737811 A，本专利申请人进行了理论和实践上的优化和改进，并将同步测量原理引入倾角传感器的设计、加工和测试，构建了新一代全量程倾角传感器，该传感器能够在之前的测量精度基础上提升两个数量级，实现分辨率为10 5度(170ng)的角度(重力加速度)测量。
【发明内容】
为进一步提升现有技术的测量精度，本发明的目的是提供一种基于谐振器同步振荡的频率检测方法及其倾角传感器，实现平面内倾角的全量程、超高精度测量。
为达到上述目的，本发明所采用的技术方案是：
一种基于同步振荡频率检测的MEMS全量程倾角传感器，包括用于感受重力加速度的质量块，该质量块的四周布置有放大梁、检测元件和同步元件；所述质量块将感受到的重力加速度转换为压力或拉力施加于放大梁上，该力经过放大梁传递并放大施加于检测元件，改变三个检测元件的刚度及固有频率。
所述检测元件的主体为检测谐振子，该检测谐振子的两侧分别布置有第一电容平板和第二电容平板，检测谐振子的两端分别连接放大梁和第一固定端，第一固定端上溅射有第一金属电极层；在第一电容平板的对侧设有第三电容平板，第一电容平板和第三电容平板构成第一平板电容，第三电容平板被固定于第二固定端上，第二固定端上溅射有第二金属电极层。
所述同步元件的主体为同步谐振子，两侧分别布置第四电容平板和第五电容平板，顶部和底部分别布置有第三固定端和第五固定端，第三固定端上溅射有第三金属电极层；在第四电容平板的对侧设有第六电容平板，第四电容平板和第六电容平板构成第二平板电容，第六电容平板被固定于第四固定端上，第四固定端上溅射有第二金属电极层，第五电容平板与第二电容平板相对并构成第三平板电容。
具有自动增益控制的振荡电路包括依次连接的馈通电流消除电路、放大器、带通滤波、移相电路、比较器和幅值调节电路，其中，馈通电流消除电路与第一金属电极层或第三金属电极层连接，幅值调节电路与第二金属电极层或第四金属电极层连接。
该传感器包括单晶硅基底、生长在单晶硅基底上的绝缘层，以及生长在绝缘层上的单晶硅结构层，所述质量块、放大梁、检测元件和同步元件都位于单晶硅结构层上，单晶硅基底起到支撑作用，保证单晶硅结构层悬空并可以自由振动。
所述的放大梁、检测元件和同步元件成为一个整体并呈放射状均匀分布于质量块周围。
所述的电容平板的间距为0.1μm-2μm。
所述的检测谐振子与同步谐振子的固有频率比例为1:1、1:3或1:9时，振荡器稳定性提升效果最为显著。
一种基于同步振荡频率检测的MEMS全量程倾角传感器的角度测量方法，质量块在受到面内重力加速度时，同时对放大梁产生压力或拉力，该力经放大梁放大并施加于检测元件上，以改变检测谐振子的固有频率，由于三个检测元件和三个同步元件被置于具有自动增益控制的振荡电路中，形成同步自激振荡，通过检测三个同步自激振荡电路的振荡频率及其变化，即可反演出整个器件所受倾角值。
通过第三平板电容的静电耦合实现两个振荡器的同步振动，以大幅降低振荡器的本底噪声，提升检测元件的频率稳定性；当第一振荡电路与第二振荡电路的自激振荡频率为1:1、1:3或1:9时，实现检测元件频率变化的同步放大，提高检测元件的检测灵敏度。
与现有技术相比，本发明至少具有以下有益效果：本发明在设置检测元件的同时，还设置有同步元件，该同步元件与检测元件静电耦合。这样，当质量块在受到面内重力加速度时，对放大梁产生压力或拉力，该力经放大梁传递并放大施加于检测元件上，以改变检测谐振子的固有频率，由于检测谐振子和同步谐振子被置于具有自动增益控制的振荡电路中，因此形成同步 自激振荡，通过检测三个同步自激振荡的振荡频率及其变化，即可计算出整个器件所受倾角值。基于硅微谐振器的振荡器频率稳定、噪音低、易于集成，依此设计的倾角传感器体积小、灵敏度高、测量范围大；基于谐振器同步振荡的频率检测方法可以实现更低的本底噪声和更高的频率稳定性，从而实现超高精度的倾角测量。
【附图说明】
图1为本发明的结构示意图。
图2为本发明的单晶硅结构层的俯视图。
图3为本发明的测量电路原理图。
图4为本发明的改进的测量电路原理图。
【具体实施方式】
下面结合附图对本发明进一步详细描述。
参见图1，基于同步振荡频率检测的MEMS全量程倾角传感器，包括单晶硅基底01，其厚度范围为400um-1000um，单晶硅基底01上生长一层二氧化硅绝缘层02，生长厚度范围为2-3um，二氧化硅绝缘层02上设有单晶硅结构层03，其厚度范围为10-25um。
参见图2，所述的单晶硅结构层03是传感器的核心部分，由质量块1、放大梁2、检测元件3和同步元件4四个模块组成。质量块1的作用是感受面内重力加速度，并将加速度转换为压力或拉力施加于放大梁2上。放大梁2、检测元件3和同步元件4构成一个整体并呈放射状均匀分布于六边形的质量块1周围，具体地说，放大梁2、检测元件3和同步元件4形成的整体布置在六边形的质量块1的边上，六边形的质量块1悬空并仅靠放大梁2支撑，放大梁2的另一端与检测元件3相连。
放大梁2包括输入梁2-1、杠杆2-2、支点2-3和输出梁2-4，输入梁2-1与六边形质量块1相连接并作为力的输入端，该力经杠杆2-2和支点2-3的放大，施加于输出梁2-4上，输出 梁2-4另一端与检测谐振子3-1相连，支点2-3较细的部分悬空(支点较细的部分指支点2-3与杠杆2-2连接的部分)，起到支点的作用，较粗的部分与单晶硅基底01相接，起固定作用，即支点2-3的固定点。更具体地说，所述输入梁2-1为一对，分别与质量块6相连且位于质量块某一边的两端，所述杠杆2-2分别自输入梁朝向中间延伸而成。所述输出梁2-4也为一对，与各自相应的杠杆2-2和支点2-3连接。也就是说，杠杆2-3的一端连接输入梁2-1，另外一端连接输出梁2-4。
参见图2，检测元件3的主体为检测谐振子3-1，其两侧设有第一电容平板3-2和第二电容平板3-3，顶部设有第一固定端3-5，第一固定端3-5上溅射有第一金属电极层3-4，在第一电容平板3-2的对侧设有第三电容平板3-8，第一电容平板3-2和第三电容平板3-8构成第一平板电容，第三电容平板3-8被固定于第二固定端3-7上，第二固定端3-7上溅射有第二金属电极层3-6。
参见图2，所述同步元件4与所述检测元件3的结构类似，其主体为同步谐振子4-1，两侧设有第四电容平板4-2和第五电容平板4-3，顶部设有第三固定端4-5，第三固定端4-5上溅射有第三金属电极层4-4，在第四电容平板4-2的对侧设有第六电容平板4-8，第四电容平板4-2和第六电容平板4-8构成第二平板电容，第六电容平板4-8被固定于第四固定端4-7上，第四固定端4-7上溅射有第四金属电极层4-6，第五电容平板4-3与第二电容平板3-3相对并构成第三平板电容，同步信号由此传递，同步谐振子4-1底部设有第五固定端4-9，第五固定端4-9较细的部分起连接作用(即第五固定端4-9通过较细的梁与同步谐振子4-1连接)并悬空设置，较粗的部分与单晶硅基地01相连接，起固定作用。
参见图2，所述第一至第四固定端都为正方形，其边长范围为180μm-600μm，第五固定端呈多边形，所述金属电极板都为略小于固定端的正方形，边长范围为150μm-250μm，所述电容平板长度范围为50μm-200μm，两个对应的电容平板的间距为0.1μm-2μm。
参见图2，典型的用于倾角测量的谐振子为双端固定谐振音叉，但对于本发明，任何适用的梁式谐振器或体模态谐振器都可以被采用。
参见图3，所述谐振元件3和同步元件4分别被置于具有自动增益控制的第一振荡电路和第二振荡电路中，振荡电路包括馈通电流消除电路5-1、放大器5-2、带通滤波5-3、移相电路5-4、比较器5-5和幅值调节电路5-6，在特定的电路参数下，所述谐振元件3和同步元件4分别与振荡电路形成自激振荡，且振荡频率为谐振子的固有频率，该频率可通过频率测量装置5-7读取。
参见图4，在上述测试方法的基础上，加入锁相环(Phase-Lock Loop，PLL)。锁相环包括了鉴相器5-8(Phase Discriminator，PD)，环路滤波器5-9(Loop Filter，LF)和压控振荡器5-10(Voltage Controlled Oscillator，VCO)，其功能相当于高Q值的带通滤波器，可以替代带通滤波器5-3，使得本底噪声更小，频率稳定性更高。
本发明的工作原理为：
质量块1在受到面内重力加速度时，同时对三对放大梁2产生压力或拉力，该力经放大梁2传递并放大施加于检测元件3上，改变了检测谐振子3-1的固有频率；由于三个检测谐振子和三个同步谐振器件被分别置于三个具有自动增益控制的同步振荡电路中，形成同步自激振荡，通过检测三个同步自激振荡电路的振荡频率及其变化，即可反演出整个器件所受的倾角值。
当同步元件4不工作时，六边形质量块1、放大梁2、检测元件3和第一振荡电路可以构成一个完整的倾角测试系统，但是由于硅微振荡器本身存在的噪声及由外界环境带来的漂移，其测试精度受到一定限制(参见专利CN 105737811 A)。当同步元件4工作时，其闭环电路内也将以同步谐振子4-1的固有频率产生自激振荡，由于同步元件4和检测元件3静电耦合，二者将形成同步自激振荡。当同步谐振子4-1与检测谐振子3-1的固有频率呈1:1、3:1或9:1时，同步效果最好，此时由检测谐振子3-1构成的振荡器频率稳定性将大大提高，由频率测量装置 5-7读取的频率信号信噪比也将大大提升，从而提高了倾角传感器的测试精度。

Claims (10)

  1. 一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：包括用于感受重力加速度的质量块(1)，该质量块(1)的四周布置有放大梁(2)、检测元件(3)和同步元件(4)，所述的检测元件(3)和同步元件(4)耦合，所述的检测元件(3)和同步元件(4)均置于具有自动增益控制的振荡电路中，保证检测元件(3)和同步元件(4)分别与各自的振荡电路形成自激振荡；所述质量块(1)将感受到的重力加速度并转换为压力或拉力施加于放大梁(2)上，该力经过放大梁(2)传递并放大施加于检测元件(3)。
  2. 根据权利要求1所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：所述检测元件(3)的主体为检测谐振子(3-1)，该检测谐振子(3-1)的两侧分别布置有第一电容平板(3-2)和第二电容平板(3-3)，检测谐振子(3-1)的两端分别连接放大梁(2)和第一固定端(3-5)，第一固定端(3-5)上溅射有第一金属电极层(3-4)；在第一电容平板(3-2)的对侧设有第三电容平板(3-8)，第一电容平板(3-2)和第三电容平板(3-8)构成第一平板电容，第三电容平板(3-8)被固定于第二固定端(3-7)上，第二固定端(3-7)上溅射有第二金属电极层(3-6)。
  3. 根据权利要求2所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：所述同步元件(4)的主体为同步谐振子(4-1)，同步谐振子(4-1)的两侧分别布置第四电容平板(4-2)和第五电容平板(4-3)，顶部和底部分别布置有第三固定端(4-5)和第五固定端(4-9)，第三固定端(4-5)上溅射有第三金属电极层(4-4)；在第四电容平板(4-2)的对侧设有第六电容平板(4-8)，第四电容平板(4-2)和第六电容平板(4-8)构成第二平板电容，第六电容平板(4-8)被固定于第四固定端(4-7)上，第四固定端(4-7)上溅射有第四金属电极层(4-6)，第五电容平板(4-3)与第二电容平板(3-3)相对并构成第三平板电容。
  4. 根据权利要求1所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：具有自动增益控制的振荡电路包括依次连接的馈通电流消除电路(5-1)、放大器(5-2)、 带通滤波(5-3)或锁相环、移相电路(5-4)、比较器(5-5)和幅值调节电路(5-6)，其中，馈通电流消除电路(5-1)与第一金属电极层(3-4)或第三金属电极层(4-4)连接，幅值调节电路(5-6)与第二金属电极层(3-6)或第四金属电极层(4-6)连接。
  5. 根据权利要求1至4中任一项所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：该传感器包括单晶硅基底(01)、生长在单晶硅基底(01)上的绝缘层(02)，以及生长在绝缘层(02)上的单晶硅结构层(03)，所述质量块(1)、放大梁(2)、检测元件(3)和同步元件(4)都位于单晶硅结构层(03)上，单晶硅基底(01)起到支撑作用，保证单晶硅结构层(03)悬空并可以自由振动。
  6. 根据权利要求1至4中任一项所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：所述的放大梁(2)、检测元件(3)和同步元件(4)成为一个整体并呈放射状均匀分布于质量块(1)周围。
  7. 根据权利要求2至4中任一项所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器，其特征在于：所述的电容平板的间距为0.1μm-2μm。
  8. 一种基于权利要求3所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器同步振荡的频率检测方法，其特征在于：包括了两个具有自动增益控制的振荡电路，即第一振荡电路和第二振荡电路，检测元件(3)被置于第一振荡电路中，同步元件(4)被置于第二振荡电路中，两个电路分别以检测元件(3)和同步元件(4)的固有频率自激振荡。通过第三平板电容的静电耦合实现两个振荡器的同步振动，将大幅降低振荡器的本底噪声，提升检测元件(3)的频率稳定性。当第一振荡电路与第二振荡电路的自激振荡频率呈现一定比例时，可以实现检测元件(3)频率变化的同步放大，从而提高检测元件(3)的检测灵敏度。
  9. 一种基于权利要求1至8中任一项所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器的角度测量方法，其特征在于：质量块(1)在受到面内重力加速度时，同时对放大梁 (2)产生压力或拉力，该力经放大梁(2)放大并施加于检测元件(3)上，以改变检测谐振子(3-1)的固有频率，由于三个检测元件(3)和三个同步元件(4)被置于三个具有自动增益控制的同步振荡电路中，形成同步自激振荡，通过检测三个同步自激振荡电路的振荡频率及其变化，即可反演出整个器件所受倾角值。
  10. 根据权利要求9所述的一种基于同步振荡频率检测的MEMS全量程倾角传感器的频率检测方法，其特征在于：通过第三平板电容的静电耦合实现两个振荡器的同步振动，以大幅降低振荡器的本底噪声，提升检测元件(3)的频率稳定性；当第一振荡电路与第二振荡电路的自激振荡频率为1:1、1:3或1:9时，实现检测元件(3)频率变化的同步放大，提高检测元件(3)的检测灵敏度。
PCT/CN2017/120360 2017-04-10 2017-12-29 基于谐振器同步振荡的频率检测方法及倾角传感器 Ceased WO2018188382A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/465,576 US20190293421A1 (en) 2017-04-10 2017-12-29 Frequency detection method based on synchronous oscillation of resonators and tilt sensor using the frequency detection method

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710231210.5 2017-04-10
CN201710231210.5A CN107179046B (zh) 2017-04-10 2017-04-10 一种基于谐振器同步振荡的频率检测方法及其倾角传感器

Publications (1)

Publication Number Publication Date
WO2018188382A1 true WO2018188382A1 (zh) 2018-10-18

Family

ID=59830906

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/120360 Ceased WO2018188382A1 (zh) 2017-04-10 2017-12-29 基于谐振器同步振荡的频率检测方法及倾角传感器

Country Status (3)

Country Link
US (1) US20190293421A1 (zh)
CN (1) CN107179046B (zh)
WO (1) WO2018188382A1 (zh)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107179046B (zh) * 2017-04-10 2020-03-17 西安交通大学 一种基于谐振器同步振荡的频率检测方法及其倾角传感器
CN110260841A (zh) * 2019-06-10 2019-09-20 东南大学 倾角传感器
CN110260835B (zh) * 2019-06-21 2021-03-16 天津理工大学 一种利用固有频率测量可变夹角角度的方法及装置
CN111579054A (zh) * 2020-06-22 2020-08-25 北京卫星环境工程研究所 基于mems的振动传感器及振动频率的测量方法
US11703521B2 (en) * 2020-12-04 2023-07-18 Honeywell International Inc. MEMS vibrating beam accelerometer with built-in test actuators
CN112924015B (zh) * 2021-03-25 2022-02-11 西安交通大学 一种基于声子频率梳的低频信号检测系统
CN114323081B (zh) * 2021-12-27 2023-06-20 中国人民解放军国防科技大学 基于非线性域模态耦合的传感器灵敏度提升方法及系统
CN115333125A (zh) * 2022-08-29 2022-11-11 河海大学 基于深度q网络优化运行方式的次同步振荡抑制方法
CN115540735B (zh) * 2022-10-10 2025-09-19 中国人民解放军国防科技大学 一种半球谐振子内外球面同心度和厚度均匀性的在位测量方法
CN118584142B (zh) * 2024-06-28 2025-04-18 内蒙古大学 一种基于耦合梁式1比3内共振现象的加速度传感器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6151965A (en) * 1998-01-21 2000-11-28 Denso Corporation Structure of angular rate sensor for minimizing output noise
WO2014037695A2 (en) * 2012-09-04 2014-03-13 Cambridge Enterprise Limited Dual and triple axis inertial sensors and methods of inertial sensing
CN105737811A (zh) * 2016-04-19 2016-07-06 西安交通大学 一种谐振式mems全量程倾角传感器
CN107179046A (zh) * 2017-04-10 2017-09-19 西安交通大学 一种基于谐振器同步振荡的频率检测方法及其倾角传感器
CN107515311A (zh) * 2017-08-18 2017-12-26 西安交通大学 一种基于同步谐振频率检测的mems加速度计

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3696193B2 (ja) * 2002-09-30 2005-09-14 富士通メディアデバイス株式会社 可変キャパシタ及びその製造方法
CN101303365B (zh) * 2008-06-23 2010-11-03 中北大学 谐振式微加速度计
JP2014052282A (ja) * 2012-09-07 2014-03-20 Rohm Co Ltd 周波数測定回路
CN106525304B (zh) * 2016-12-12 2018-12-18 西安交通大学 一种线型微纳材料扭转性能测量用mems谐振式扭矩传感器

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6151965A (en) * 1998-01-21 2000-11-28 Denso Corporation Structure of angular rate sensor for minimizing output noise
WO2014037695A2 (en) * 2012-09-04 2014-03-13 Cambridge Enterprise Limited Dual and triple axis inertial sensors and methods of inertial sensing
CN105737811A (zh) * 2016-04-19 2016-07-06 西安交通大学 一种谐振式mems全量程倾角传感器
CN107179046A (zh) * 2017-04-10 2017-09-19 西安交通大学 一种基于谐振器同步振荡的频率检测方法及其倾角传感器
CN107515311A (zh) * 2017-08-18 2017-12-26 西安交通大学 一种基于同步谐振频率检测的mems加速度计

Also Published As

Publication number Publication date
CN107179046A (zh) 2017-09-19
CN107179046B (zh) 2020-03-17
US20190293421A1 (en) 2019-09-26

Similar Documents

Publication Publication Date Title
WO2018188382A1 (zh) 基于谐振器同步振荡的频率检测方法及倾角传感器
CN107515311A (zh) 一种基于同步谐振频率检测的mems加速度计
US5969249A (en) Resonant accelerometer with flexural lever leverage system
EP3835795B1 (en) Vibrating beam accelerometer with pressure damping
US11584635B2 (en) Dual-output microelectromechanical resonator and method of manufacture and operation thereof
CN104698222B (zh) 三轴单片集成谐振电容式硅微加速度计及其加工方法
Pandit et al. An ultra-high resolution resonant MEMS accelerometer
CN102147423B (zh) 双轴集成全解耦硅微谐振式加速度计
CN111812355B (zh) 一种低应力敏感度硅微谐振式加速度计结构
CN113740560B (zh) 一种弱耦合谐振式加速度传感器
CN103439529B (zh) 基于片式集成高精度测温结构的硅振梁加速度计
CN105737811A (zh) 一种谐振式mems全量程倾角传感器
CN111175540A (zh) 一种基于单向电同步的超谐同步谐振式加速度计
Ren et al. An in-run automatic mode-matching method with amplitude correction and phase compensation for MEMS disk resonator gyroscope
CN108008149A (zh) 对应力不敏感的自校准硅微谐振式加速度计
CN115265850A (zh) 一种差分刚度扰动模态局域化的高灵敏微压传感器
Li et al. A resonant sensor composed of quartz double ended tuning fork and silicon substrate for digital acceleration measurement
Ge et al. A novel MEMS quadruple mass gyroscope with superior overall performance via dual-umbrella-like driving architecture
CN112881753A (zh) 阻尼可调型硅微音叉谐振式加速度计结构
CN116953284A (zh) 一种基于多级差分输出的高精度硅基mems谐振加速度计
CN112782428A (zh) 具有压力阻尼的振梁加速度计
Gadola et al. 600 µdps/√ Hz, 1.2 mm2 MEMS pitch gyroscope
CN206132802U (zh) 一种加速度计探头及加速度计系统
RU2447403C1 (ru) Микромеханический гироскоп
CN118409108B (zh) 应力自隔离的石英谐振加速度计芯片及石英谐振加速度计

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17905520

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17905520

Country of ref document: EP

Kind code of ref document: A1