WO2020002381A1 - Composant micromécanique et procédé de fonctionnement d'un composant micromécanique - Google Patents

Composant micromécanique et procédé de fonctionnement d'un composant micromécanique Download PDF

Info

Publication number
WO2020002381A1
WO2020002381A1 PCT/EP2019/066917 EP2019066917W WO2020002381A1 WO 2020002381 A1 WO2020002381 A1 WO 2020002381A1 EP 2019066917 W EP2019066917 W EP 2019066917W WO 2020002381 A1 WO2020002381 A1 WO 2020002381A1
Authority
WO
WIPO (PCT)
Prior art keywords
frequency
drive
vibration
micromechanical component
mass oscillator
Prior art date
Application number
PCT/EP2019/066917
Other languages
German (de)
English (en)
Inventor
Reinhard Neul
Andreas Lassl
Niels Bode
Matthias Kuehnel
Michael Curcic
Nils Felix Kuhlmann
Peter Degenfeld-Schonburg
Original Assignee
Robert Bosch Gmbh
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 Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Publication of WO2020002381A1 publication Critical patent/WO2020002381A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
    • G01C19/56—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
    • G01C19/5719—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using planar vibrating masses driven in a translation vibration along an axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
    • B81B3/0035—Constitution or structural means for controlling the movement of the flexible or deformable elements
    • B81B3/004—Angular deflection
    • B81B3/0045—Improve properties related to angular swinging, e.g. control resonance frequency
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
    • G01C19/56—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
    • G01C19/5719—Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using planar vibrating masses driven in a translation vibration along an axis
    • G01C19/5726—Signal processing

Definitions

  • the invention is based on a method according to the preamble of
  • Micromechanical components of this type (microelectromechanical systems, MEMS) with vibratable structures are known from the prior art in a variety of embodiments.
  • MEMS microelectromechanical systems
  • One of the areas of application for such components is, for example, use as rotation rate sensors in
  • micromechanical structures are used in the control of micromirrors
  • Micro projectors and microscanners used. All of these applications use vibrating micromechanical structures that are appropriate
  • the detection structures then detect rotational speeds by measuring the Coriolis accelerations that occur with the aid of detection modes that are excited by these accelerations.
  • Micromirrors use certain vibration modes to deflect the mirrors as intended.
  • Structures are electrostatic or piezoelectric, but also other physical principles are possible, such as magnetic or electrodynamic drives.
  • feed-forward electrodes take up additional space and the voltages must be kept in the application-specific integrated circuit (ASIC), so that additional costs and increased power consumption compared to open-loop systems arise.
  • ASIC application-specific integrated circuit
  • micromechanical structures such as those used in the systems mentioned, in principle have many other vibration modes, some of which can lead to undesirable and disadvantageous effects. So show
  • Offset behavior e.g. so-called offset jumps.
  • Vibration modes are excited, which lead to disturbances in the detection signals due to their waveforms.
  • micromirrors it is possible that, under certain circumstances, larger deflections of the mirrors cannot be achieved because the drive energy is parasitic
  • Vibration modes flow and are therefore not available for the desired deflections. Under certain circumstances, these vibrations can even lead to undesired mechanical stops and, in the worst case, to
  • Drive mode can be set to a target frequency that matches the frequency of the detection mode and has the least possible coupling with parasitic vibration modes.
  • the frequency of modes (in particular the drive mode) can be set specifically, the
  • Components in the ASIC can be saved.
  • the noise caused by the positive feedback electrodes can be prevented.
  • the frequencies of the detection modes can also change as a function of the drive amplitude.
  • the frequencies of the detection modes can also change as a function of the drive amplitude.
  • Shift of the drive mode can be set specifically so that it does not meet any of the above-mentioned frequency conditions for exciting parasitic modes.
  • the targeted shift according to the invention of individual vibration frequencies as a function of the drive amplitude is achieved by using a
  • This effect can be modeled using the Duffing equation.
  • This is the equation of motion for a system capable of oscillation, which, in addition to the usual linear relationship between amplitude and restoring force, has another term, the one
  • the influence of this nonlinear term and thus the strength of the mechanical nonlinearity is characterized by a parameter ß 0 and depends on the spring structures used in the design of the component.
  • the frequency / oscillation of a duffing oscillator is no longer independent of the deflection compared to the linear case, but becomes as follows with increasing deflection a compared to the base frequency f 0 (ie the frequency with small deflections where the non-linearity is negligibly small) Moved way:
  • the shift is therefore proportional to the strength ß 0 of the non-linearity and increases quadratically with the deflection a.
  • the nonlinearity parameter ⁇ 0 can be positive or negative.
  • the case ß o> 0 corresponds to a restoring force that increases more than linearly with larger deflections ("stiffening" of the spring), while the case ß o ⁇ 0 corresponds to a restoring force that with larger ones
  • the mass oscillator is perpendicular to the drive vibration
  • Vibration modes often form the basis of a number of inertial sensors, in particular rotation rate sensors.
  • the drive vibration is from of the drive structure, while the detection vibration is excited by external forces, for example by the Coriolis force, and a measurement of these external influences is thereby made possible.
  • the frequencies of the drive vibration and the detection vibration coincide as exactly as possible.
  • the method according to the invention can advantageously be used to compensate for a discrepancy between the two frequencies.
  • the structure capable of oscillation is preferably such that the base frequency of the drive oscillation is specifically offset relative to the detection frequency and the offset together with the production-related fluctuations is compensated for by the displacement of the drive frequency according to the invention.
  • the offset is preferably chosen to be negative, ie the base frequency is originally smaller than the detection frequency and is shifted towards the detection frequency by increasing the amplitude.
  • the offset is preferably positive in the case of a nonlinearity with ⁇ o ⁇ 0, so that the offset is compensated for by increasing the frequency with large amplitudes.
  • the micromechanical component has a positive feedback electrode, the positive feedback electrode reducing the frequency of the detection oscillation by electrostatic coupling to the mass oscillator.
  • Mitkoppelelektroden for influencing the detection frequency are basically known from the prior art.
  • a frequency comparison between the drive frequency and the detection frequency can advantageously be carried out in such a way that the positive feedback electrode lowers the detection frequency to a certain extent, so that the drive frequency and the detection frequency move closer together.
  • the method according to the invention can now additionally increase the
  • the positive feedback electrode only takes over part of the compensation, the corresponding structures (i.e. the electrode itself and the associated control loops) can advantageously be smaller and the voltage at the voltage necessary for the compensation
  • Coupling electrode can advantageously be reduced.
  • the target frequency is selected such that the drive oscillation has minimal coupling with parasitic oscillation modes.
  • Frequency spectrum of the structure capable of oscillation contains in addition to the
  • Natural frequency usually other frequencies that are positioned at integer multiples of the natural frequency (harmonics or higher).
  • the drive mode and its higher harmonics in the frequency spectrum have as little overlap as possible with the parasitic modes, or are spaced as far apart from them.
  • the shift of the frequency of the drive mode according to the invention can advantageously be set up in such a way that this distance is maximized and the resulting coupling with the parasitic modes is minimized.
  • the adjustment to the target frequency is carried out by increasing the amplitude of the drive vibration.
  • Another object of the present invention is a micromechanical component according to claim 5.
  • the mass oscillator and the associated suspension are such that the vibration behavior has a non-linear characteristic, that is to say the restoring force and the deflection are related in a non-linear manner.
  • the resulting amplitude dependence of the frequency can either be positive (ß o > 0) and cause an increase in the frequency with large amplitudes, or correspondingly negative (ß o ⁇ 0), so that an increase in the amplitude leads to a reduction in the frequency.
  • This effect is used according to the invention to shift the drive frequency by adjusting the amplitude so that it matches a desired target frequency.
  • the mass oscillator is excited by the drive structure to deflections that lie outside the linear range (ie outside the range in which the restoring force and deflection are essentially proportional to one another).
  • the drive structure can have, for example, a control unit that adjusts or regulates the strength of the drive in such a way that the Amplitude of the mass oscillator the desired drive frequency is generated.
  • the mass oscillator is elastically supported by at least one spring, the spring being designed in such a way that the amplitude of the drive oscillation increases to one
  • Stiffness or softening of the spring leads. Stiffening here means that the ratio of restoring force and deflection increases with increasing deflection (ß o > 0), while softening corresponds to a decrease in this ratio (ß o ⁇ 0).
  • all spring structures have such a stiffening or softening if they are deflected beyond the range in which the ratio of the restoring force and deflection is approximately proportional.
  • this mechanical non-linearity is preferably influenced in a targeted manner via the design of the springs. For example, the shape or cross-section of the springs or the choice of material can be used to influence this.
  • the component has a central coupling electrode which is electrostatically coupled to the mass oscillator, the electrostatic coupling being designed in such a way that the frequency of the detection oscillation is reduced. This advantageously ensures that the frequency comparison is generated by the interaction of two different mechanisms. For one thing, there will be a shift in
  • the detection frequency is lowered by the action of the positive feedback electrode. This interaction allows
  • Figure 1 shows a schematic representation of an embodiment of a mass oscillator with a non-linear elastic mounting.
  • Figure 2 shows a schematic representation of a further embodiment of a mass oscillator with a non-linear elastic mounting.
  • FIG. 3 shows a schematic representation of a method for adapting the frequency of the detection oscillation according to the prior art.
  • Figures 4a to 4c show a schematic representation of various embodiments of the method according to the invention.
  • a movable structure 1 is connected to the substrate via springs 2 at anchor points 3 and can preferably move parallel to the y-axis 6.
  • a compression force acts in the x direction 5 on the spring bar 2, so that the properties of the spring 2 change depending on the drive amplitude. In particular, this changes the frequency as a function of
  • This non-linearity and thus the frequency shift can be set by a suitable choice of the stiffness of the spring 2.
  • FIG. 2 shows another possible embodiment of a non-linear one
  • the springs 2 have an additional one
  • FIG. 3 schematically shows the procedure for frequency adjustment between the drive and detection modes according to the prior art.
  • the horizontal axis 7 corresponds to the frequency and the vertical axis 8 to the amplitude.
  • the case shown here corresponds to a linear behavior of the drive mode, ie the frequency of the drive mode is independent of the amplitude and therefore has the
  • the resonance frequency 9 of the detection mode is designed so that it is a few hundred Hertz above the frequency 10 of the drive mode.
  • the stiffness of the detection mode is reduced until the resulting frequency shift 11 matches the two frequencies.
  • FIGS. 4a-c show the frequency adjustment according to the invention via the mechanical non-linearities.
  • FIG. 4a shows the procedure for springs in which the drive mode has a mechanical non-linearity with ⁇ o > 0.
  • the frequency of the drive mode essentially corresponds to the base frequency 13, which in this case is lower than the desired target frequency 9.
  • the frequency of the drive mode is shifted towards higher frequencies following the curve 12 shown. In this case, the amplitude of the drive mode is increased until the frequency reaches the desired target frequency 9.
  • Frequency adjustment advantageously requires no additional feed-through electrodes or further control loops in the ASIC.
  • the mechanical non-linearity can be used to lower the required voltage at the feedforward electrode by increasing the resonance frequency of the drive mode to such an extent that the voltage required for the frequency reduction 11 turns out to be significantly lower, which advantageously means a cheaper ASIC Process allowed.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Signal Processing (AREA)
  • Gyroscopes (AREA)

Abstract

L'invention concerne un procédé de fonctionnement d'un composant micromécanique, le composant micromécanique présentant un oscillateur à masse et une structure d'entraînement, la structure d'entraînement étant configurée pour exciter une oscillation d'entraînement non linéaire de l'oscillateur à masse. L'oscillation d'entraînement présente une fréquence de base pour de petites amplitudes, et, pour de plus grandes amplitudes, présente une fréquence qui est décalée par rapport à la fréquence de base, l'adaptation de l'amplitude de l'oscillation d'entraînement permettant de régler la fréquence de l'oscillation d'entraînement sur une fréquence cible, la fréquence cible étant supérieure ou inférieure à la fréquence de base. L'invention concerne en outre un composant micromécanique, présentant un oscillateur à masse et une structure d'entraînement, la structure d'entraînement étant configurée pour exciter une oscillation d'entraînement non linéaire de l'oscillateur à masse.
PCT/EP2019/066917 2018-06-27 2019-06-25 Composant micromécanique et procédé de fonctionnement d'un composant micromécanique WO2020002381A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102018210478.6 2018-06-27
DE102018210478.6A DE102018210478A1 (de) 2018-06-27 2018-06-27 Mikromechanisches Bauelement und Verfahren zum Betrieb eines mikromechanischen Bauelements

Publications (1)

Publication Number Publication Date
WO2020002381A1 true WO2020002381A1 (fr) 2020-01-02

Family

ID=67107430

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2019/066917 WO2020002381A1 (fr) 2018-06-27 2019-06-25 Composant micromécanique et procédé de fonctionnement d'un composant micromécanique

Country Status (2)

Country Link
DE (1) DE102018210478A1 (fr)
WO (1) WO2020002381A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10320725A1 (de) * 2003-05-08 2004-11-25 Robert Bosch Gmbh Mikromechanischer Bewegungssensor
WO2005083356A1 (fr) * 2004-02-23 2005-09-09 Halliburton Energy Services, Inc. Masses couplees sensibles au mouvement
DE102013212059A1 (de) * 2013-06-25 2015-01-08 Robert Bosch Gmbh Mikromechanischer Inertialsensor und Verfahren zum Betrieb eines Inertialsensors

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10320725A1 (de) * 2003-05-08 2004-11-25 Robert Bosch Gmbh Mikromechanischer Bewegungssensor
WO2005083356A1 (fr) * 2004-02-23 2005-09-09 Halliburton Energy Services, Inc. Masses couplees sensibles au mouvement
DE102013212059A1 (de) * 2013-06-25 2015-01-08 Robert Bosch Gmbh Mikromechanischer Inertialsensor und Verfahren zum Betrieb eines Inertialsensors

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SCHWARZELBACH O: "New approach for resonant frequency matching of tuning fork gyroscopes by using a non-linear drive concept", TRANSDUCERS '01/EUROSENSORS XV : DIGEST OF TECHNICAL PAPERS / THE 11TH INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS AND ACTUATORS, JUNE 10 - 14, 2001, MUNICH, GERMANY, BERLIN [U.A.] : SPRINGER, DE, vol. 1, 10 June 2001 (2001-06-10), pages 464 - 467, XP008122254 *

Also Published As

Publication number Publication date
DE102018210478A1 (de) 2020-01-02

Similar Documents

Publication Publication Date Title
DE102009000606A1 (de) Mikromechanische Strukturen
DE19739877C2 (de) Mechanischer Resonator mit variabler Resonanzfrequenz
EP1373831B1 (fr) Detecteur de vitesse de rotation
EP1478902B1 (fr) Capteur de vitesse de rotation
DE10107327B4 (de) Zur Verhinderung einer unnötigen Oszillation geeigneter Winkelgeschwindigkeitssensor
DE102010006584B4 (de) Corioliskreisel mit Korrektureinheiten und Verfahren zur Reduktion des Quadraturbias
WO1995029383A1 (fr) Oscillateur micromecanique pour gyrometre a oscillations
EP3250931B9 (fr) Capteur d'accélération à compensation de la force de ressort
WO2002066929A1 (fr) Detecteur de vitesse de rotation
DE102008049647A1 (de) Mikromechanisches Element und Sensor zur Überwachung eines mikromechanischen Elements
DE102012219660B4 (de) Mechanisches Bauteil
DE102012004808A1 (de) Vorrichtung zur Beeinflussung der Schwingungsübertragung zwischen zwei Einheiten
DE102008041310A1 (de) Optisches Element
DE102009009562A1 (de) Kombinierter Bewegungssensor zum Einsatz in Feedback-Regelsystemen zur Schwingungsisolation
DE102007051820A1 (de) Mikromechanisches Bauelement mit erhöhter Steifigkeit
DE102017217653A1 (de) Mikromechanisches Bauteil, Herstellungsverfahren für ein mikromechanisches Bauteil und Verfahren zum Anregen einer Bewegung eines verstellbaren Teils um eine Rotationsachse
EP2993372A1 (fr) Groupe electrogene ayant une masse inertielle formee par un composant electronique et commutateur de commande associe
DE102012219650B4 (de) Mechanisches Bauteil, mechanisches System und Verfahren zum Betreiben eines mechanischen Bauteils
DE102008054749A1 (de) Drehratensensor und Verfahren zum Betrieb eines Drehratensensors
WO2017012748A1 (fr) Capteur de lacet à mouvements perturbateurs minimisés en mode d'entraînement
DE102009000475A1 (de) Verfahren zur Quadraturkompensation
DE102008038293A1 (de) Verfahren und Vorrichtung zum Erzeugen von elektrischer Energie aus einer mechanischen Anregungsschwingung
DE102011006453A1 (de) Verfahren zum Betrieb eines Drehratensensors
WO2020002381A1 (fr) Composant micromécanique et procédé de fonctionnement d'un composant micromécanique
DE10320725A1 (de) Mikromechanischer Bewegungssensor

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: 19734354

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: 19734354

Country of ref document: EP

Kind code of ref document: A1