WO1998037380A1 - Tuning fork gyro with split electrode - Google Patents

Tuning fork gyro with split electrode Download PDF

Info

Publication number
WO1998037380A1
WO1998037380A1 PCT/US1998/003618 US9803618W WO9837380A1 WO 1998037380 A1 WO1998037380 A1 WO 1998037380A1 US 9803618 W US9803618 W US 9803618W WO 9837380 A1 WO9837380 A1 WO 9837380A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrodes
comb electrodes
proof mass
comb
center
Prior art date
Application number
PCT/US1998/003618
Other languages
French (fr)
Inventor
Paul A. Ward
Eric M. Hildebrant
Lance C. Niles
Marc S. Weinberg
Anthony S. Kourepenis
Original Assignee
The Charles Stark Draper Laboratory, Inc.
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 The Charles Stark Draper Laboratory, Inc. filed Critical The Charles Stark Draper Laboratory, Inc.
Priority to EP98906689A priority Critical patent/EP0970349B1/en
Priority to CA002282510A priority patent/CA2282510A1/en
Priority to DE69831143T priority patent/DE69831143T2/en
Priority to JP53699098A priority patent/JP4458441B2/en
Publication of WO1998037380A1 publication Critical patent/WO1998037380A1/en

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01CMEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C19/00Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
    • G01C19/56Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
    • G01C19/5719Turn-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

Definitions

  • Micromechanical tuning fork gyroscopes such as that shown in Fig. 1 are known.
  • the tuning fork gyroscope includes silicon proof masses which are suspended by support flexures above a glass substrate, and comb electrodes which are used for oscillating the proof masses.
  • Metallic sense electrodes are disposed on the glass substrate below the proof masses for detecting Coriolis motion by indicating out- of-plane capacitance changes. Because the tuning fork gyroscope operates in this manner, it is desirable that the amplitude of the oscillation be held at a predetermined constant in order to provide a more accurate output indicating rate.
  • the amplitude of the oscillating motor of tuning fork gyroscopes is typically controlled by a conventional servo loop connected to a single capacitive in-plane pick-off
  • center electrode In this technique motor position is converted to a proportional voltage by measuring charge variation on the center electrode which is biased with a DC voltage. The resulting motor position signal is amplified and detected by a full wave rectifier. The rectifier output is then filtered, and the filtered voltage compared against a reference voltage; the difference forming an error voltage. This error voltage is then used to control the motor drive amplitude using a loop controller to adjust motor amplitude to a predetermined constant.
  • this particular technique has a potential drawback.
  • the conventional servo loop technique may have some instability in the center electrode.
  • the sensitivity of the DC biased center electrode varies slowly over time due to a spurious charge accumulation on the glass substrate beneath the center electrode. As this charge accumulates on the glass, the sensitivity of the center electrode is modified.
  • the loop controller calls for modified drive force to compensate. The result is a motor amplitude transient wherein amplitude changes over time as substrate charge accumulates. This will result in lower accuracy than is otherwise possible because of the relationship between amplitude and Coriolis force in the system.
  • a tuning fork gyroscope includes a plurality of center and outer electrodes.
  • the total proof mass structure comprises two independent masses, a right and a left, connected by a series of beams and flexures .
  • Charge into the proof mass structure is the mechanism by which Coriolis Force is measured.
  • Center and outer motor plurality allows generation and detection of proof mass motion while minimizing charge injection into the total proof mass structure resulting from inequalities in the amplitude and/or phase of the relative proof masses.
  • each mass cancels the charge generated by its own motion, thereby reducing the in-phase bias errors and minimizing limitations on dynamic range. Because each proof mass interacts with independent split center and outer electrodes having equal and opposite potentials, the net charge generated in the total proof mass structure from amplitude mismatch errors is minimized. Splitting both the center and outer motor electrodes desensitizes the gyro to errors from charge injection into the proof mass from mismatch in the amplitude between the right and left proof masses. Charge injection results from each proof mass' interaction with the excitations used to provide both the electrostatic forcing and detection of proof mass motion.
  • a net charge injection occurs if the charge generated from the right proof mass and left proof mass are not equal and opposite, a prevailing condition if the oscillatory displacements of the right and left proof masses are mismatched in amplitude and/or phase.
  • the net current injected into the proof mass is the gyroscope output signal.
  • This current flows through the anchors into a transimpedence amplifier which converts charge (the integral of current) into an output voltage.
  • the transimpedence amplifier holds the proof mass at virtual ground. Maintaining electrical symmetry greatly reduces erroneous signals from in-plane motion, from common mode proof mass translation normal to the substrate, and from charge transients. With opposite biases on the sense electrodes, the desired gyroscope output is the differential vertical displacement.
  • Fig. 1 is a diagram of a prior art tuning fork gyroscope
  • Fig. 2 is a diagram of a tuning fork gyroscope with a plurality of center electrodes
  • Fig. 3 is an alternative configuration of the tuning fork gyroscope of Fig. 2;
  • Figs 4 and 5 illustrate circuits for applying motor bias
  • Fig. 6 is a diagram of the tuning fork gyroscope with a plurality of outer motor electrodes.
  • the tuning fork gyroscope includes first and second proof masses 3a, 3b, first and second motor electrodes 5a, 5b, first and second sense electrodes 7a, 7b, first and second center electrodes 9a, 9b, and a substrate 11.
  • the center electrodes, sense electrodes and motor electrodes are disposed on the substrate.
  • the proof masses are disposed over the sense electrodes, being supported by flexures 13a, 13b.
  • the flexures are attached to the substrate at anchor points 15 and permit movement of the proof masses relative to the sense electrodes.
  • Each proof mass includes combs extending outward from first and second sides thereof.
  • the center electrodes and motor electrodes also include combs.
  • the combs of motor electrode 5a are interleaved with the combs of proof mass 3a
  • the combs of center electrode 9a are interleaved with the combs of proof mass 3a
  • the combs of center electrode 9b are interleaved with the combs of proof mass 3b
  • the combs of motor electrode 5b are interleaved with the combs of proof mass 3b.
  • the operation of the tuning fork gyroscope is electromechanical.
  • Time varying drive signals 17a, 17b are provided to motor electrodes 5a, 5b, respectively.
  • the drive signals generate electrostatic coupling between interleaved combs 19a, 19b, 21a, 21b, attached to the motor electrodes 5a, 5b and proof masses 3a, 3b, respectively, and impart an oscillating force upon the proof masses along a motor drive axis 23.
  • the oscillating force causes the proof masses to oscillate in a plane of vibration 25.
  • an inertial input such as a rotational rate
  • the proof masses deflect out of the plane of vibration.
  • Sense biases +V g , -V g are applied to the sense electrodes 7a, 7b, respectively to establish a potential between the sense electrodes 7a, 7b and the proof masses 3a, 3b, respectively, so that changes in capacitance between the electrodes and the adjacent proof masses as a result of the deflection out of the plane of vibration can be measured.
  • Measurement of an inertial input with the tuning fork gyroscope is based upon the principal of Coriolis force.
  • F c 2m ⁇ XV (1)
  • V is the proof mass velocity
  • Mass and velocity are known for the tuning fork gyroscope. Hence, inertial input motion can be measured based upon charge variation between the proof masses and sense electrodes. However, in order to achieve accurate results it is important that the proof mass velocity remain constant.
  • An oscillator circuit 27 is employed to measure proof mass velocity from at least one of the center electrodes 9a, 9b and, in response thereto, vary the drive signals 17a, 17b to compensate for variations in velocity.
  • Bias potentials +V B , -V B are applied to the center electrodes 9a, 9b, respectively, in order to facilitate measurement of proof mass velocity through feedback signals 29a, 29b.
  • the bias signals +V B , -V B are coupled to the center electrodes 9a, 9b through resistors, 31a, 31b. Charge variations caused by displacement of the proof masses in the plane of vibration are then detected and employed as feedback.
  • the bias signals +V B , -V B may be DC voltage, AC voltage or a combination AC+DC voltage. Further, the bias signals are equal in magnitude and opposite in polarity. Circuits for applying the motor bias are shown in Figs. 4 and 5. In Fig. 4, the bias may only be DC, but in Fig. 5 AC or DC or AC+DC is suitable.
  • the changing proximity between the proof mass and the adjacent center electrode, which results in charge variations, is indicated through the electrostatic coupling of the interleaved combs.
  • the proof mass oscillates proximity changes over time. Consequently, the potential between the interleaved comb electrodes changes over time.
  • the rate of change of the potential of the feedback signals from the center electrodes are thus indicative of proof mass velocity.
  • the feedback signals are compared with reference signals and the result of the comparison is employed to adjust the drive signals .
  • the oppositely biased center electrodes reduce the effect of undesirable substrate charging by providing electrical symmetry between left and right sides of the tuning fork gyroscope. Symmetry exists where for each bias applied to the tuning fork gyroscope another bias of equal magnitude and opposite polarity exists and where the gyroscope can be bisected into two regions of equal and opposite electrical characteristics. Symmetry reduces the effects of charge transients and sensitivity to vertical translation because the oppositely biased signals applied to the center electrodes tend to cancel. For example, voltages induced in the gyroscope substrate by the bias potentials are equal and opposite, so that substrate charging effect on in- phase bias are reduced.
  • Fig. 3 illustrates an alternative center electrode configuration.
  • the center electrodes 9a, 9b each include first and second respective sets of comb electrodes 33a, 33b, 35a, 35b, which are interleaved with the comb electrodes 37, 39 of the proof masses 3a, 3b, respectively. That is, each center electrode interacts with both proof masses.
  • the center electrodes have bias potentials +V B , -V B , applied thereto, respectively, in order to facilitate measurement of proof mass velocity through feedback signals 41, 43.
  • the bias potentials may be DC voltage, AC voltage or a combination DC+AC voltage.
  • each center electrode provides a measurement of the velocity of both proof masses
  • a single feedback signal from one of the center electrodes may by utilized by the oscillator circuit to maintain a constant proof mass velocity.
  • a differential readout 45 may be employed with the feedback signals from each center electrode to provide an indication of proof mass velocity. Since each of the center electrodes interact with both the proof masses, currents injected into the proof masses through the center electrodes are equal and opposite, and thus effectively cancel .
  • FIG. 6 Another alternative embodiment is illustrated in Fig. 6.
  • the center electrodes 9a, 9b are split as described with respect to Fig. 3, above.
  • the gyro includes split left 38a, 38b and right 38c, 38d motor electrodes.
  • +VAC is applied to electrodes 38a, 38c
  • -VAC is applied to electrodes 38b, 38d.
  • Sensing oscillatory motion includes providing an even number of oscillatory motion sensing elements, biasing first and second groups of the oscillatory motion sensing elements with first and second bias potentials of opposite polarity, the first and second groups of oscillatory motion sensing elements being equal in number, and then sensing oscillatory motion with at least one of the oscillatory motion sensing elements.
  • Such injection is typically through interleaved comb electrodes, and arrangement of oscillatory motion sensing elements can be such that each element is coupled to only one oscillating mass, or such that each element is coupled to more than one oscillating mass.
  • arrangement of oscillatory motion sensing elements can be such that each element is coupled to only one oscillating mass, or such that each element is coupled to more than one oscillating mass.
  • the symmetry of the device will change as described above.
  • the technique of balancing the injected current through an even number of electrodes also applies to rotary vibrating gyroscopes.

Landscapes

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

Abstract

A micromechanical tuning fork gyro having two center electrodes (9a, 9b). The two center electrodes are excited with bias potentials of opposite polarity. The oppositely biased center electrodes provide electrical symmetry across the gyroscope and thereby reduce charge transients and sensitivity to vertical translation. Currents injected directly into the proof masses (3a, 3b) are equal and opposite and thus cancel. Motor lift forces acting on the proof masses and interleaved electrodes equal, hence the proof masses move in pure translation, thereby reducing in-phase bias. Further, any pure translation normal to the plane of the gyroscope does not effect sense axis output signals.

Description

TITLE OF THE INVENTION
"TUNING FORK GYRO WITH SPLIT ELECTRODE"
CROSS-REFERENCE TO RELATED APPLICATIONS Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable
BACKGROUND OF THE INVENTION
Micromechanical tuning fork gyroscopes such as that shown in Fig. 1 are known. The tuning fork gyroscope includes silicon proof masses which are suspended by support flexures above a glass substrate, and comb electrodes which are used for oscillating the proof masses. Metallic sense electrodes are disposed on the glass substrate below the proof masses for detecting Coriolis motion by indicating out- of-plane capacitance changes. Because the tuning fork gyroscope operates in this manner, it is desirable that the amplitude of the oscillation be held at a predetermined constant in order to provide a more accurate output indicating rate.
The amplitude of the oscillating motor of tuning fork gyroscopes is typically controlled by a conventional servo loop connected to a single capacitive in-plane pick-off
("center electrode") . In this technique motor position is converted to a proportional voltage by measuring charge variation on the center electrode which is biased with a DC voltage. The resulting motor position signal is amplified and detected by a full wave rectifier. The rectifier output is then filtered, and the filtered voltage compared against a reference voltage; the difference forming an error voltage. This error voltage is then used to control the motor drive amplitude using a loop controller to adjust motor amplitude to a predetermined constant. However, this particular technique has a potential drawback.
The conventional servo loop technique may have some instability in the center electrode. The sensitivity of the DC biased center electrode varies slowly over time due to a spurious charge accumulation on the glass substrate beneath the center electrode. As this charge accumulates on the glass, the sensitivity of the center electrode is modified. In response, the loop controller calls for modified drive force to compensate. The result is a motor amplitude transient wherein amplitude changes over time as substrate charge accumulates. This will result in lower accuracy than is otherwise possible because of the relationship between amplitude and Coriolis force in the system.
BRIEF SUMMARY OF THE INVENTION In accordance with the present invention, a tuning fork gyroscope includes a plurality of center and outer electrodes. The total proof mass structure comprises two independent masses, a right and a left, connected by a series of beams and flexures . Charge into the proof mass structure is the mechanism by which Coriolis Force is measured. Center and outer motor plurality allows generation and detection of proof mass motion while minimizing charge injection into the total proof mass structure resulting from inequalities in the amplitude and/or phase of the relative proof masses. By forming an electrode configuration that provides each of the masses with split center and outer motor electrodes, errors from mismatch in relative amplitude or phase can be rejected. By applying excitations of equal and opposite potentials to each set of independent center and outer motor electrodes, each mass cancels the charge generated by its own motion, thereby reducing the in-phase bias errors and minimizing limitations on dynamic range. Because each proof mass interacts with independent split center and outer electrodes having equal and opposite potentials, the net charge generated in the total proof mass structure from amplitude mismatch errors is minimized. Splitting both the center and outer motor electrodes desensitizes the gyro to errors from charge injection into the proof mass from mismatch in the amplitude between the right and left proof masses. Charge injection results from each proof mass' interaction with the excitations used to provide both the electrostatic forcing and detection of proof mass motion. A net charge injection occurs if the charge generated from the right proof mass and left proof mass are not equal and opposite, a prevailing condition if the oscillatory displacements of the right and left proof masses are mismatched in amplitude and/or phase. By splitting the center and outer motor electrodes evenly and applying excitations of opposing magnitude, each proof mass cancels the charge inherent in its own motion, thereby reducing in- phase bias errors and dynamic range limitations. The center electrodes reduce substrate charging effects and reduce undesirable motor lift forces by providing equal numbers of oppositely biased center electrodes. The center electrodes are arranged to provide electrical symmetry across the tuning fork gyroscope. Because of the symmetry, voltages induced in the substrate by the center electrodes are equal and opposite so that the effect of substrate charging on in- phase bias is reduced. Further, currents injected directly into the proof masses are equal and opposite, and therefore tend to cancel. As a result, motor lift forces are equal and the proof masses move in pure translation, thereby reducing in-phase bias. The net current injected into the proof mass is the gyroscope output signal. This current flows through the anchors into a transimpedence amplifier which converts charge (the integral of current) into an output voltage. The transimpedence amplifier holds the proof mass at virtual ground. Maintaining electrical symmetry greatly reduces erroneous signals from in-plane motion, from common mode proof mass translation normal to the substrate, and from charge transients. With opposite biases on the sense electrodes, the desired gyroscope output is the differential vertical displacement.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING The invention would be more fully understood in light of the following detailed description of the drawing in which:
Fig. 1 is a diagram of a prior art tuning fork gyroscope;
Fig. 2 is a diagram of a tuning fork gyroscope with a plurality of center electrodes;
Fig. 3 is an alternative configuration of the tuning fork gyroscope of Fig. 2;
Figs 4 and 5 illustrate circuits for applying motor bias; and Fig. 6 is a diagram of the tuning fork gyroscope with a plurality of outer motor electrodes.
DETAILED DESCRIPTION OF THE INVENTION A micromechanical tuning fork gyroscope is illustrated in Fig. 2. The tuning fork gyroscope includes first and second proof masses 3a, 3b, first and second motor electrodes 5a, 5b, first and second sense electrodes 7a, 7b, first and second center electrodes 9a, 9b, and a substrate 11. The center electrodes, sense electrodes and motor electrodes are disposed on the substrate. The proof masses are disposed over the sense electrodes, being supported by flexures 13a, 13b. The flexures are attached to the substrate at anchor points 15 and permit movement of the proof masses relative to the sense electrodes. Each proof mass includes combs extending outward from first and second sides thereof. The center electrodes and motor electrodes also include combs. The combs of motor electrode 5a are interleaved with the combs of proof mass 3a, the combs of center electrode 9a are interleaved with the combs of proof mass 3a, the combs of center electrode 9b are interleaved with the combs of proof mass 3b and the combs of motor electrode 5b are interleaved with the combs of proof mass 3b.
The operation of the tuning fork gyroscope is electromechanical. Time varying drive signals 17a, 17b are provided to motor electrodes 5a, 5b, respectively. The drive signals generate electrostatic coupling between interleaved combs 19a, 19b, 21a, 21b, attached to the motor electrodes 5a, 5b and proof masses 3a, 3b, respectively, and impart an oscillating force upon the proof masses along a motor drive axis 23. The oscillating force causes the proof masses to oscillate in a plane of vibration 25. In response to an inertial input such as a rotational rate, the proof masses deflect out of the plane of vibration. Sense biases +Vg, -Vg are applied to the sense electrodes 7a, 7b, respectively to establish a potential between the sense electrodes 7a, 7b and the proof masses 3a, 3b, respectively, so that changes in capacitance between the electrodes and the adjacent proof masses as a result of the deflection out of the plane of vibration can be measured. Measurement of an inertial input with the tuning fork gyroscope is based upon the principal of Coriolis force. Fc = 2mΩXV (1)
Where m is mass
V is the proof mass velocity and
Ω is the input rate
Mass and velocity are known for the tuning fork gyroscope. Hence, inertial input motion can be measured based upon charge variation between the proof masses and sense electrodes. However, in order to achieve accurate results it is important that the proof mass velocity remain constant.
An oscillator circuit 27 is employed to measure proof mass velocity from at least one of the center electrodes 9a, 9b and, in response thereto, vary the drive signals 17a, 17b to compensate for variations in velocity. Bias potentials +VB, -VB are applied to the center electrodes 9a, 9b, respectively, in order to facilitate measurement of proof mass velocity through feedback signals 29a, 29b. The bias signals +VB, -VB are coupled to the center electrodes 9a, 9b through resistors, 31a, 31b. Charge variations caused by displacement of the proof masses in the plane of vibration are then detected and employed as feedback. The bias signals +VB, -VB may be DC voltage, AC voltage or a combination AC+DC voltage. Further, the bias signals are equal in magnitude and opposite in polarity. Circuits for applying the motor bias are shown in Figs. 4 and 5. In Fig. 4, the bias may only be DC, but in Fig. 5 AC or DC or AC+DC is suitable.
The changing proximity between the proof mass and the adjacent center electrode, which results in charge variations, is indicated through the electrostatic coupling of the interleaved combs. As the proof mass oscillates, proximity changes over time. Consequently, the potential between the interleaved comb electrodes changes over time. The rate of change of the potential of the feedback signals from the center electrodes are thus indicative of proof mass velocity. In order to maintain constant proof mass velocity, the feedback signals are compared with reference signals and the result of the comparison is employed to adjust the drive signals .
The oppositely biased center electrodes reduce the effect of undesirable substrate charging by providing electrical symmetry between left and right sides of the tuning fork gyroscope. Symmetry exists where for each bias applied to the tuning fork gyroscope another bias of equal magnitude and opposite polarity exists and where the gyroscope can be bisected into two regions of equal and opposite electrical characteristics. Symmetry reduces the effects of charge transients and sensitivity to vertical translation because the oppositely biased signals applied to the center electrodes tend to cancel. For example, voltages induced in the gyroscope substrate by the bias potentials are equal and opposite, so that substrate charging effect on in- phase bias are reduced. Further, motor lift forces acting on the proof masses and interleaved comb electrodes are equal and hence the proof masses move in pure translation, thus reducing in-phase bias. Another benefit of symmetry is that pure translation normal to the plane of the gyroscope does not produce a sense axis output. Thus, the sense electrode output only reflects actual inertial motion. The net current injected into the proof mass is the gyroscope output signal. This current flows through the anchors into a transimpedence amplifier which converts charge (the integral of current) into an output voltage. The transimpedence amplifier holds the proof mass at virtual ground. Maintaining electrical symmetry greatly reduces erroneous signals from in-plane motion, from common mode proof mass translation normal to the substrate, and from charge transients. With opposite biases on the sense electrodes, the desired gyroscope output is the differential vertical displacement. For these reasons the center electrodes are disposed symmetrically upon the substrate .
Fig. 3 illustrates an alternative center electrode configuration. In the alternative embodiment, the center electrodes 9a, 9b each include first and second respective sets of comb electrodes 33a, 33b, 35a, 35b, which are interleaved with the comb electrodes 37, 39 of the proof masses 3a, 3b, respectively. That is, each center electrode interacts with both proof masses. As with the previously described embodiment, the center electrodes have bias potentials +VB, -VB, applied thereto, respectively, in order to facilitate measurement of proof mass velocity through feedback signals 41, 43. The bias potentials may be DC voltage, AC voltage or a combination DC+AC voltage. Because each center electrode provides a measurement of the velocity of both proof masses, a single feedback signal from one of the center electrodes may by utilized by the oscillator circuit to maintain a constant proof mass velocity. Alternatively, a differential readout 45 may be employed with the feedback signals from each center electrode to provide an indication of proof mass velocity. Since each of the center electrodes interact with both the proof masses, currents injected into the proof masses through the center electrodes are equal and opposite, and thus effectively cancel .
Another alternative embodiment is illustrated in Fig. 6. In this embodiment the center electrodes 9a, 9b are split as described with respect to Fig. 3, above. Additionally, the gyro includes split left 38a, 38b and right 38c, 38d motor electrodes. To achieve symmetry +VAC is applied to electrodes 38a, 38c, and -VAC is applied to electrodes 38b, 38d.
It will now be apparent in view of the above description that the present invention defines a method for sensing oscillatory motion of an oscillating mass. Sensing oscillatory motion includes providing an even number of oscillatory motion sensing elements, biasing first and second groups of the oscillatory motion sensing elements with first and second bias potentials of opposite polarity, the first and second groups of oscillatory motion sensing elements being equal in number, and then sensing oscillatory motion with at least one of the oscillatory motion sensing elements. By arranging the oscillatory motion sensing element in equal groups which are biased with signals of opposite polarity, stray current and voltage injection into other elements of the device tend to cancel. Such injection is typically through interleaved comb electrodes, and arrangement of oscillatory motion sensing elements can be such that each element is coupled to only one oscillating mass, or such that each element is coupled to more than one oscillating mass. Depending on the arrangement, the symmetry of the device will change as described above. Hence, the technique of balancing the injected current through an even number of electrodes also applies to rotary vibrating gyroscopes. It should be understood that various changes or modifications may be made from the embodiment being disclosed. Accordingly, the invention is not to be viewed as limited except by the scope and spirit of the appended claims .

Claims

CLAIMS What is claimed is: 1. An apparatus for detecting the position of an oscillating member comprising: a first sense electrode disposed on a substrate and being proximate to said member; a first bias potential applied to said first sense electrode; a second sense electrode disposed on said substrate; and a second bias potential applied to said second sense electrode, said second bias potential being equal to said first bias potential in magnitude and opposite thereto in polarity.
2. The apparatus of claim 1 wherein the member is a first proof mass having comb electrodes which are interleaved with comb electrodes on said first sense electrode.
3. The apparatus of claim 2 including a second proof mass having comb electrodes which are interleaved with comb electrodes on said second sense electrode.
4. The apparatus of claim 3 including a second proof mass having comb electrodes which are interleaved with comb electrodes on said first and second electrodes, the comb electrodes of said first proof mass also being interleaved with comb electrodes on said first and second electrodes.
5. The apparatus of claim 4 wherein said first and second bias potentials are AC, DC, or AC+DC.
6. The apparatus of claim 5 wherein said position detecting apparatus is electrically symmetrical on either side of an axis which bisects said position detecting apparatus into first and second parts, first part containing first center electrode and second part containing second center electrode.
7. The apparatus of claim 6 wherein DC potential at said motor electrodes is zero volts.
8. The apparatus of claim 1 including first and second split motor electrodes disposed on said substrate proximate said oscillating member.
9. A micromechanical tuning fork gyroscope for measuring an inertial input, comprising: a substrate; first and second sense electrodes disposed symmetrically on said substrate; at least first and second proof masses disposed over said first and second sense electrodes, respectively, said first and second proof masses having comb electrodes extended from respective inner and outer sides thereof; first and second motor electrodes disposed symmetrically on said substrate, said first and second motor electrodes having comb electrodes, said comb electrodes of said first and second motor electrodes interleaved with the outer side comb electrodes of said first and second proof masses, respectively; and first and second oppositely biased center electrodes disposed symmetrically on said substrate, at least one of said center electrodes being coupled to said first proof mass by interleaved comb electrodes and providing a feedback signal indicative of velocity of said first proof mass.
10. The tuning fork gyroscope of claim 9 wherein said comb electrodes of said first center electrode are interleaved with said comb electrodes of said first proof mass and said comb electrodes of said second center electrode are interleaved with said comb electrodes of said second proof mass .
11. The tuning fork gyroscope of claim 10 wherein said first center electrode includes comb electrodes interleaved with a portion of said comb electrodes of said second proof mass and said second center electrode includes comb electrodes interleaved with a portion of said comb electrodes of said first proof mass.
12. A method for sensing oscillatory motion of at least one oscillating mass on a device comprising the steps of: providing an even number of oscillatory motion sensing elements; biasing first and second groups of the oscillatory motion sensing elements with first and second potentials of opposite polarity, the first and second groups of oscillatory motion sensing elements being equal in number; and sensing oscillatory motion of at least one oscillating mass with at least one oscillatory motion sensing element.
13. The method of claim 12 including a further step of arranging the oscillatory motion sensing elements to provide electrical symmetry between first and second halves of the device .
14. The method of claim 13 wherein the device is a tuning fork gyroscope, the oscillating mass is a proof mass and said providing step includes the step of providing first and second center electrodes .
15. The method of claim 14 wherein the tuning fork gyroscope includes first and second proof masses with comb electrodes, the first and second center electrodes have comb electrodes, and said biasing step includes applying AC, DC or AC+DC voltage potentials to the first and second center electrodes.
16. The method of claim 15 wherein said arranging step includes interleaving the comb electrodes of the first center electrode with the comb electrodes of the first proof mass, and interleaving the comb electrodes of the second center electrode with the comb of the second proof mass .
17. The method of claim 15 wherein said arranging step includes interleaving a first half of the comb electrodes of the first center electrode with half of the comb electrodes of the first proof mass; interleaving a second half of the comb electrodes of the first center electrode with half of the comb electrodes of the second proof mass ; interleaving a first half of the comb electrodes of the second center electrode with half of the comb electrodes of the first proof mass; and interleaving a second half of the comb electrodes of the second center electrode with half of the comb electrodes of the second proof mass.
18. The method of claim 12 including the further step of imparting oscillatory motion to the at least one oscillating mass with at least one split electrode having at least first and second sub-parts.
19. The method of claim 18 including the further step of applying equal and opposite electrical potentials to the respective first and second sub-parts.
PCT/US1998/003618 1997-02-24 1998-02-24 Tuning fork gyro with split electrode WO1998037380A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP98906689A EP0970349B1 (en) 1997-02-24 1998-02-24 Tuning fork gyro with split electrode
CA002282510A CA2282510A1 (en) 1997-02-24 1998-02-24 Tuning fork gyro with split electrode
DE69831143T DE69831143T2 (en) 1997-02-24 1998-02-24 TUNING CRANK WITH SPLIT ELEPHANT
JP53699098A JP4458441B2 (en) 1997-02-24 1998-02-24 Tuning fork gyro with split electrodes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US08/805,013 US5911156A (en) 1997-02-24 1997-02-24 Split electrode to minimize charge transients, motor amplitude mismatch errors, and sensitivity to vertical translation in tuning fork gyros and other devices
US08/805,013 1997-02-24

Publications (1)

Publication Number Publication Date
WO1998037380A1 true WO1998037380A1 (en) 1998-08-27

Family

ID=25190493

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1998/003618 WO1998037380A1 (en) 1997-02-24 1998-02-24 Tuning fork gyro with split electrode

Country Status (6)

Country Link
US (1) US5911156A (en)
EP (1) EP0970349B1 (en)
JP (1) JP4458441B2 (en)
CA (1) CA2282510A1 (en)
DE (1) DE69831143T2 (en)
WO (1) WO1998037380A1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2338785A (en) * 1998-06-22 1999-12-29 Aisin Seiki Angular rate sensor
JP2001153659A (en) * 1999-11-29 2001-06-08 Murata Mfg Co Ltd Angular velocituy sensor
JP2010210640A (en) * 2010-05-26 2010-09-24 Murata Mfg Co Ltd Vibration gyro and electronic device using the same
US8331075B2 (en) 2006-03-01 2012-12-11 Tokimec Inc. Electro-static floating type gyro device
DE102005058965B4 (en) * 2004-12-10 2014-09-11 Denso Corporation gyro sensor
WO2014184033A1 (en) * 2013-05-13 2014-11-20 Robert Bosch Gmbh Sensing system for a micromechanical sensor device
WO2018197860A1 (en) * 2017-04-27 2018-11-01 Cambridge Enterprise Ltd High performance micro-electro-mechanical systems accelerometer with electrostatic control of proof mass
IT201700097531A1 (en) * 2017-08-30 2019-03-02 St Microelectronics Srl INERTIAL FM SENSOR AND FUNCTIONING METHOD OF THE INERTIAL FM SENSOR

Families Citing this family (45)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6230563B1 (en) 1998-06-09 2001-05-15 Integrated Micro Instruments, Inc. Dual-mass vibratory rate gyroscope with suppressed translational acceleration response and quadrature-error correction capability
DE60044782D1 (en) * 1999-09-17 2010-09-16 Kionix Inc ELECTRICALLY DECORATED MICRO-MADE CIRCLE
US6311555B1 (en) * 1999-11-17 2001-11-06 American Gnc Corporation Angular rate producer with microelectromechanical system technology
FR2809174B1 (en) * 2000-05-16 2002-07-12 Commissariat Energie Atomique VIBRATING STRUCTURE WITH TWO COUPLED OSCILLATORS, ESPECIALLY FOR A GYROMETER
SG103276A1 (en) * 2001-01-03 2004-04-29 Inst Materials Research & Eng Vibratory in-plane tunnelling gyroscope
US6598475B2 (en) * 2001-09-20 2003-07-29 Honeywell International Inc. Micromechanical inertial sensor having increased pickoff resonance damping
WO2003031912A2 (en) * 2001-10-05 2003-04-17 The Charles Stark Draper Laboratory, Inc. Tuning fork gyroscope
US6611168B1 (en) 2001-12-19 2003-08-26 Analog Devices, Inc. Differential parametric amplifier with physically-coupled electrically-isolated micromachined structures
DE10203515A1 (en) * 2002-01-30 2003-08-07 Bosch Gmbh Robert Micromechanical rotation rate sensor
US7089792B2 (en) * 2002-02-06 2006-08-15 Analod Devices, Inc. Micromachined apparatus utilizing box suspensions
EP2327959B1 (en) * 2002-02-06 2012-09-12 Analog Devices, Inc. Micromachined gyroscope
US6792802B2 (en) * 2002-03-07 2004-09-21 Honeywell International Inc. Noise source for starting MEMS gyroscope
US6769304B2 (en) * 2002-04-02 2004-08-03 Honeywell International Inc. Reduced start time for MEMS gyroscope
US6715353B2 (en) 2002-04-25 2004-04-06 Honeywell International, Inc. MEMS gyroscope with parametric gain
US6718823B2 (en) * 2002-04-30 2004-04-13 Honeywell International Inc. Pulse width modulation drive signal for a MEMS gyroscope
US6823733B2 (en) * 2002-11-04 2004-11-30 Matsushita Electric Industrial Co., Ltd. Z-axis vibration gyroscope
US6817244B2 (en) * 2003-01-06 2004-11-16 Honeywell International Inc. Methods and systems for actively controlling movement within MEMS structures
US6993969B2 (en) * 2003-03-27 2006-02-07 Denso Corporation Vibration type of micro gyro sensor
US20050062362A1 (en) * 2003-08-28 2005-03-24 Hongyuan Yang Oscillatory gyroscope
US7036372B2 (en) * 2003-09-25 2006-05-02 Kionix, Inc. Z-axis angular rate sensor
US20050066728A1 (en) * 2003-09-25 2005-03-31 Kionix, Inc. Z-axis angular rate micro electro-mechanical systems (MEMS) sensor
US7043985B2 (en) * 2004-01-13 2006-05-16 Georgia Tech Research Corporation High-resolution in-plane tuning fork gyroscope and methods of fabrication
CN1954193B (en) * 2004-04-14 2010-09-01 模拟设备公司 Coupling apparatus for inertial sensors
US7036373B2 (en) * 2004-06-29 2006-05-02 Honeywell International, Inc. MEMS gyroscope with horizontally oriented drive electrodes
US7478557B2 (en) * 2004-10-01 2009-01-20 Analog Devices, Inc. Common centroid micromachine driver
TWI245110B (en) * 2004-11-12 2005-12-11 Ind Tech Res Inst Apparatus of micro angular motion detector and fabrication method thereof
US7300814B2 (en) * 2004-12-16 2007-11-27 The Charles Stark Draper Laboratory, Inc. Method for fabricating micro-mechanical devices
US7302848B2 (en) 2005-03-10 2007-12-04 The Charles Stark Draper Laboratory, Inc. Force compensated comb drive
US7421897B2 (en) 2005-04-14 2008-09-09 Analog Devices, Inc. Cross-quad and vertically coupled inertial sensors
JP4830757B2 (en) * 2006-02-28 2011-12-07 株式会社デンソー Angular velocity sensor and manufacturing method thereof
US7401515B2 (en) * 2006-03-28 2008-07-22 Honeywell International Inc. Adaptive circuits and methods for reducing vibration or shock induced errors in inertial sensors
US7383729B2 (en) 2006-10-12 2008-06-10 Honeywell International, Inc. Tuning fork gyro with sense plate read-out
EP1959234A1 (en) * 2007-02-13 2008-08-20 STMicroelectronics S.r.l. Microelectromechanical gyroscope with suppression of capacitive coupling spurious signals and control method of a microelectromechanical gyroscope
US8061201B2 (en) 2007-07-13 2011-11-22 Georgia Tech Research Corporation Readout method and electronic bandwidth control for a silicon in-plane tuning fork gyroscope
US8187902B2 (en) 2008-07-09 2012-05-29 The Charles Stark Draper Laboratory, Inc. High performance sensors and methods for forming the same
US8664951B2 (en) * 2009-03-30 2014-03-04 Honeywell International Inc. MEMS gyroscope magnetic sensitivity reduction
CN101957201B (en) * 2009-07-13 2012-10-03 上海丽恒光微电子科技有限公司 Capacitive MEMS gyroscope and method of making the same
WO2011026100A1 (en) 2009-08-31 2011-03-03 Georgia Tech Research Corporation Bulk acoustic wave gyroscope with spoked structure
WO2013140488A1 (en) * 2012-03-19 2013-09-26 日立オートモティブシステムズ株式会社 Angular velocity sensor
US20140026659A1 (en) * 2012-07-27 2014-01-30 Biao Zhang Mems device and a method of using the same
WO2015190363A1 (en) * 2014-06-09 2015-12-17 株式会社村田製作所 Mems structure
US9562767B2 (en) 2014-08-12 2017-02-07 Honeywell International Inc. Systems and methods for improving MEMS gyroscope start time
CN108599738A (en) * 2018-03-22 2018-09-28 中国科学院上海微系统与信息技术研究所 A kind of closed-loop driving circuit suitable for MEMS resonant formula sensor
US11530917B2 (en) 2018-09-24 2022-12-20 The Charles Stark Draper Laboratory, Inc. Methods for fabricating silicon MEMS gyroscopes with upper and lower sense plates
EP3712560A3 (en) 2018-10-16 2020-12-16 The Charles Stark Draper Laboratory, Inc. Method and system for control and readout of tuning fork gyroscope

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5349855A (en) * 1992-04-07 1994-09-27 The Charles Stark Draper Laboratory, Inc. Comb drive micromechanical tuning fork gyro
US5604312A (en) * 1994-11-25 1997-02-18 Robert Bosch Gmbh Rate-of-rotation sensor
US5635638A (en) * 1995-06-06 1997-06-03 Analog Devices, Inc. Coupling for multiple masses in a micromachined device
US5728936A (en) * 1995-08-16 1998-03-17 Robert Bosch Gmbh Rotary speed sensor

Family Cites Families (115)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32931A (en) * 1861-07-30 Machine for tupvning tapering forms
US33479A (en) * 1861-10-15 Improved blacksmith s portable forge
CH359552A (en) * 1957-07-20 1962-01-15 Boelkow Entwicklungen Kg Measuring and control device for very low speeds
GB989101A (en) * 1961-07-11 1965-04-14 Mini Of Aviat London Improvements in gyroscope apparatus
US3370458A (en) * 1965-09-10 1968-02-27 W C Dillon & Company Inc Mechanical force gauge
US3696429A (en) * 1971-05-24 1972-10-03 Cutler Hammer Inc Signal cancellation system
US3913035A (en) * 1974-07-01 1975-10-14 Motorola Inc Negative resistance high-q-microwave oscillator
US4044305A (en) * 1975-03-17 1977-08-23 The Charles Stark Draper Laboratory, Inc. Apparatus for providing a displacement representative of the magnitude of a signal
JPS6025926B2 (en) * 1976-10-01 1985-06-21 シャープ株式会社 Crystal oscillator
US4155257A (en) * 1977-05-23 1979-05-22 The Singer Company Temperature compensated vibrating beam accelerometer
US4122448A (en) * 1977-07-21 1978-10-24 Westinghouse Electric Corp. Automatic phase and gain balance controller for a baseband processor
US4144764A (en) * 1978-05-11 1979-03-20 Schaevitz Engineering Servo amplifier for an electrically damped accelerometer
US4234666A (en) * 1978-07-26 1980-11-18 Western Electric Company, Inc. Carrier tapes for semiconductor devices
US4321500A (en) * 1979-12-17 1982-03-23 Paroscientific, Inc. Longitudinal isolation system for flexurally vibrating force transducers
US4336718A (en) * 1980-09-08 1982-06-29 Lear Siegler, Inc. Control circuit for accelerometer
US4342227A (en) * 1980-12-24 1982-08-03 International Business Machines Corporation Planar semiconductor three direction acceleration detecting device and method of fabrication
US4499778A (en) * 1981-02-03 1985-02-19 Northrop Corporation Flexure mount assembly for a dynamically tuned gyroscope and method of manufacturing same
US4381672A (en) * 1981-03-04 1983-05-03 The Bendix Corporation Vibrating beam rotation sensor
US4447753A (en) * 1981-03-25 1984-05-08 Seiko Instruments & Electronics Ltd. Miniature GT-cut quartz resonator
DE3112560C2 (en) * 1981-03-30 1983-01-27 M.A.N.- Roland Druckmaschinen AG, 6050 Offenbach Proximity switch which, by means of excitation and detection of a field, indicates the presence or absence of field-changing objects in a defined distance range from the proximity switch using a binary signal
US4406992A (en) * 1981-04-20 1983-09-27 Kulite Semiconductor Products, Inc. Semiconductor pressure transducer or other product employing layers of single crystal silicon
JPS57188121A (en) * 1981-05-15 1982-11-19 Seiko Instr & Electronics Ltd Frequency adjusting method of coupling oscillator
CH642461A5 (en) * 1981-07-02 1984-04-13 Centre Electron Horloger ACCELEROMETER.
US4495499A (en) * 1981-09-08 1985-01-22 David Richardson Integrated oscillator-duplexer-mixer
US4414852A (en) * 1981-09-14 1983-11-15 Gould Inc. Automatic zero balance circuit
US4654663A (en) * 1981-11-16 1987-03-31 Piezoelectric Technology Investors, Ltd. Angular rate sensor system
US4411741A (en) * 1982-01-12 1983-10-25 University Of Utah Apparatus and method for measuring the concentration of components in fluids
DE3213720C2 (en) * 1982-04-14 1985-09-05 Bodenseewerk Gerätetechnik GmbH, 7770 Überlingen Dynamically coordinated cardan suspension with two degrees of freedom
US4651564A (en) * 1982-09-30 1987-03-24 Honeywell Inc. Semiconductor device
US4478077A (en) * 1982-09-30 1984-10-23 Honeywell Inc. Flow sensor
US4478076A (en) * 1982-09-30 1984-10-23 Honeywell Inc. Flow sensor
US4621925A (en) * 1982-11-11 1986-11-11 Fujitsu Limited Fiber-optic gyro
US4596158A (en) * 1983-01-05 1986-06-24 Litton Systems, Inc. Tuned gyroscope with dynamic absorber
US4522072A (en) * 1983-04-22 1985-06-11 Insouth Microsystems, Inc. Electromechanical transducer strain sensor arrangement and construction
US4490772A (en) * 1983-06-13 1984-12-25 Blickstein Martin J Voltage and mechanically variable trimmer capacitor
US4619001A (en) * 1983-08-02 1986-10-21 Matsushita Electric Industrial Co., Ltd. Tuning systems on dielectric substrates
US4590801A (en) * 1983-09-02 1986-05-27 Sundstrand Data Control, Inc. Apparatus for measuring inertial specific force and angular rate of a moving body
US4585083A (en) * 1983-11-01 1986-04-29 Shinko Denshi Company Ltd. Mechanism for detecting load
US4628283A (en) * 1983-11-07 1986-12-09 The Narda Microwave Corporation Hermetically sealed oscillator with dielectric resonator tuned through dielectric window by adjusting screw
US4783237A (en) * 1983-12-01 1988-11-08 Harry E. Aine Solid state transducer and method of making same
US4600934A (en) * 1984-01-06 1986-07-15 Harry E. Aine Method of undercut anisotropic etching of semiconductor material
FR2558263B1 (en) * 1984-01-12 1986-04-25 Commissariat Energie Atomique DIRECTIVE ACCELEROMETER AND METHOD FOR MANUFACTURING IT WITH MICROLITHOGRAPHY
GB2158579B (en) 1984-01-23 1988-07-13 Piezoelectric Technology Inves Angular rate sensor system
US4899587A (en) * 1984-01-23 1990-02-13 Piezoelectric Technology Investors, Limited Method for sensing rotation using vibrating piezoelectric elements
USRE32931E (en) 1984-01-23 1989-05-30 Piezoelectric Technology Investors, Inc. Vibratory angular rate sensor system
US4538461A (en) * 1984-01-23 1985-09-03 Piezoelectric Technology Investors, Inc. Vibratory angular rate sensing system
US4524619A (en) * 1984-01-23 1985-06-25 Piezoelectric Technology Investors, Limited Vibratory angular rate sensor system
US4598585A (en) * 1984-03-19 1986-07-08 The Charles Stark Draper Laboratory, Inc. Planar inertial sensor
US4699006A (en) * 1984-03-19 1987-10-13 The Charles Stark Draper Laboratory, Inc. Vibratory digital integrating accelerometer
CA1234705A (en) * 1984-03-22 1988-04-05 Suzushi Kimura Angular velocity sensor
GB8407847D0 (en) * 1984-03-27 1984-05-02 Emi Ltd Sensing apparatus
US4674180A (en) * 1984-05-01 1987-06-23 The Foxboro Company Method of making a micromechanical electric shunt
US4680606A (en) * 1984-06-04 1987-07-14 Tactile Perceptions, Inc. Semiconductor transducer
US4644793A (en) * 1984-09-07 1987-02-24 The Marconi Company Limited Vibrational gyroscope
JPS6197572A (en) * 1984-10-19 1986-05-16 Nissan Motor Co Ltd Manufacture of semiconductor acceleration sensor
US4674319A (en) * 1985-03-20 1987-06-23 The Regents Of The University Of California Integrated circuit sensor
US4735506A (en) * 1985-04-01 1988-04-05 Litton Systems, Inc. Phase nulling optical gyroscope
US4705659A (en) * 1985-04-01 1987-11-10 Motorola, Inc. Carbon film oxidation for free-standing film formation
US4764244A (en) * 1985-06-11 1988-08-16 The Foxboro Company Resonant sensor and method of making same
US4639690A (en) * 1985-07-05 1987-01-27 Litton Systems, Inc. Tunable, dielectric-resonator-stabilized oscillator and method of tuning same
US4744249A (en) * 1985-07-25 1988-05-17 Litton Systems, Inc. Vibrating accelerometer-multisensor
US4679434A (en) * 1985-07-25 1987-07-14 Litton Systems, Inc. Integrated force balanced accelerometer
US4744248A (en) * 1985-07-25 1988-05-17 Litton Systems, Inc. Vibrating accelerometer-multisensor
JPS6293668A (en) * 1985-10-21 1987-04-30 Hitachi Ltd Angular speed/acceleration detector
JPS6295421A (en) * 1985-10-22 1987-05-01 Tokyo Keiki Co Ltd Gyroscope
GB2183040B (en) 1985-11-19 1990-02-07 Stc Plc Transducer
US4761743A (en) * 1985-12-02 1988-08-02 The Singer Company Dynamic system analysis in a vibrating beam accelerometer
US4736629A (en) * 1985-12-20 1988-04-12 Silicon Designs, Inc. Micro-miniature accelerometer
US4747312A (en) * 1986-02-21 1988-05-31 Fischer & Porter Co. Double-loop Coriolis type mass flowmeter
US4712439A (en) * 1986-02-24 1987-12-15 Henry North Apparatus for producing a force
US4670092A (en) * 1986-04-18 1987-06-02 Rockwell International Corporation Method of fabricating a cantilever beam for a monolithic accelerometer
US4922756A (en) * 1988-06-20 1990-05-08 Triton Technologies, Inc. Micro-machined accelerometer
JPS6341080A (en) * 1986-08-06 1988-02-22 Nissan Motor Co Ltd Semiconductor acceleration sensor
FR2604791B1 (en) * 1986-10-02 1988-11-25 Commissariat Energie Atomique METHODS OF MANUFACTURING A PIEZORESISTIVE GAUGE AND AN ACCELEROMETER COMPRISING SUCH A GAUGE
US4743789A (en) * 1987-01-12 1988-05-10 Puskas William L Variable frequency drive circuit
US4727752A (en) * 1987-02-04 1988-03-01 Sundstrand Data Control, Inc. Pseudosinusoidal oscillator drive system
US4884446A (en) * 1987-03-12 1989-12-05 Ljung Per B Solid state vibrating gyro
GB2202325B (en) * 1987-03-19 1992-02-05 Stc Plc Fibre optic gyro
US4805456A (en) * 1987-05-19 1989-02-21 Massachusetts Institute Of Technology Resonant accelerometer
US4815472A (en) * 1987-06-01 1989-03-28 The Regents Of The University Of Michigan Multipoint pressure-sensing catheter system
US5013396A (en) * 1987-06-01 1991-05-07 The Regents Of The University Of Michigan Method of making an ultraminiature pressure sensor
US4881410A (en) * 1987-06-01 1989-11-21 The Regents Of The University Of Michigan Ultraminiature pressure sensor and method of making same
US4851080A (en) * 1987-06-29 1989-07-25 Massachusetts Institute Of Technology Resonant accelerometer
GB8716047D0 (en) * 1987-07-08 1987-08-12 Thorn Emi Electronics Ltd Rate sensor
US4789803A (en) * 1987-08-04 1988-12-06 Sarcos, Inc. Micropositioner systems and methods
JPS6481343A (en) * 1987-09-24 1989-03-27 Nec Corp Manufacture of integrated circuit
US4808948A (en) * 1987-09-28 1989-02-28 Kulicke And Soffa Indusries, Inc. Automatic tuning system for ultrasonic generators
US5216490A (en) 1988-01-13 1993-06-01 Charles Stark Draper Laboratory, Inc. Bridge electrodes for microelectromechanical devices
US5016072A (en) * 1988-01-13 1991-05-14 The Charles Stark Draper Laboratory, Inc. Semiconductor chip gyroscopic transducer
US5060039A (en) * 1988-01-13 1991-10-22 The Charles Stark Draper Laboratory, Inc. Permanent magnet force rebalance micro accelerometer
US5195371A (en) 1988-01-13 1993-03-23 The Charles Stark Draper Laboratory, Inc. Semiconductor chip transducer
US4890812A (en) * 1988-02-01 1990-01-02 Litton Systems, Inc. Temperature compensated mount for supporting a ring laser gyro
US4900971A (en) * 1988-03-10 1990-02-13 Seiko Electronic Components Ltd. Face shear mode quartz crystal resonator
US4929860A (en) * 1988-05-17 1990-05-29 Sundstrand Data Control, Inc. Electrode configuration for vibrating beam transducers
US4882933A (en) * 1988-06-03 1989-11-28 Novasensor Accelerometer with integral bidirectional shock protection and controllable viscous damping
US4855544A (en) * 1988-09-01 1989-08-08 Honeywell Inc. Multiple level miniature electromechanical accelerometer switch
GB2224159B (en) * 1988-09-09 1992-07-08 Seiko Electronic Components Resonator
US5055838A (en) * 1988-12-09 1991-10-08 The Regents Of The University Of Michigan Silicon tactile imaging array and method of making same
US4893509A (en) * 1988-12-27 1990-01-16 General Motors Corporation Method and product for fabricating a resonant-bridge microaccelerometer
US5025346A (en) * 1989-02-17 1991-06-18 Regents Of The University Of California Laterally driven resonant microstructures
US4901586A (en) * 1989-02-27 1990-02-20 Sundstrand Data Control, Inc. Electrostatically driven dual vibrating beam force transducer
JPH02306111A (en) * 1989-05-19 1990-12-19 Matsushita Electric Ind Co Ltd Angular velocity detector
US4981359A (en) * 1989-06-19 1991-01-01 Litton Systems, Inc. Ring laser gyroscope dither drive system and method
CA1332969C (en) 1989-09-29 1994-11-08 Francois Paquet Analog torque rebalance loop for a tuned rotor gyroscope
DE69102590T2 (en) 1990-05-18 1994-10-06 British Aerospace Inertial sensors.
US5090809A (en) * 1990-06-04 1992-02-25 Ferrar Carl M Modulation frequency control in a fiber optic rotation sensor
US5205171A (en) 1991-01-11 1993-04-27 Northrop Corporation Miniature silicon accelerometer and method
US5241861A (en) 1991-02-08 1993-09-07 Sundstrand Corporation Micromachined rate and acceleration sensor
US5094537A (en) 1991-03-08 1992-03-10 Honeywell Inc. Signal processing system for correcting ring laser gyroscope readout
US5203208A (en) 1991-04-29 1993-04-20 The Charles Stark Draper Laboratory Symmetrical micromechanical gyroscope
US5233874A (en) 1991-08-19 1993-08-10 General Motors Corporation Active microaccelerometer
FR2700065B1 (en) 1992-12-28 1995-02-10 Commissariat Energie Atomique Method of manufacturing accelerometers using silicon on insulator technology.
US5481914A (en) * 1994-03-28 1996-01-09 The Charles Stark Draper Laboratory, Inc. Electronics for coriolis force and other sensors
KR100374804B1 (en) 1995-05-25 2003-05-09 삼성전자주식회사 Vibration type gyroscope
KR100374803B1 (en) 1995-05-25 2003-05-12 삼성전자주식회사 Tuning fork type gyroscope

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5349855A (en) * 1992-04-07 1994-09-27 The Charles Stark Draper Laboratory, Inc. Comb drive micromechanical tuning fork gyro
US5604312A (en) * 1994-11-25 1997-02-18 Robert Bosch Gmbh Rate-of-rotation sensor
US5635638A (en) * 1995-06-06 1997-06-03 Analog Devices, Inc. Coupling for multiple masses in a micromachined device
US5728936A (en) * 1995-08-16 1998-03-17 Robert Bosch Gmbh Rotary speed sensor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0970349A4 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2338785A (en) * 1998-06-22 1999-12-29 Aisin Seiki Angular rate sensor
US6250157B1 (en) 1998-06-22 2001-06-26 Aisin Seiki Kabushiki Kaisha Angular rate sensor
GB2338785B (en) * 1998-06-22 2002-10-30 Aisin Seiki Angular rate sensor
JP2001153659A (en) * 1999-11-29 2001-06-08 Murata Mfg Co Ltd Angular velocituy sensor
DE102005058965B4 (en) * 2004-12-10 2014-09-11 Denso Corporation gyro sensor
US8331075B2 (en) 2006-03-01 2012-12-11 Tokimec Inc. Electro-static floating type gyro device
JP2010210640A (en) * 2010-05-26 2010-09-24 Murata Mfg Co Ltd Vibration gyro and electronic device using the same
WO2014184033A1 (en) * 2013-05-13 2014-11-20 Robert Bosch Gmbh Sensing system for a micromechanical sensor device
WO2018197860A1 (en) * 2017-04-27 2018-11-01 Cambridge Enterprise Ltd High performance micro-electro-mechanical systems accelerometer with electrostatic control of proof mass
US11340253B2 (en) 2017-04-27 2022-05-24 Cambridge Enterprise Limited High performance micro-electro-mechanical systems accelerometer with electrostatic control of proof mass
IT201700097531A1 (en) * 2017-08-30 2019-03-02 St Microelectronics Srl INERTIAL FM SENSOR AND FUNCTIONING METHOD OF THE INERTIAL FM SENSOR
EP3450992A1 (en) * 2017-08-30 2019-03-06 STMicroelectronics S.r.l. Fm inertial sensor and method for operating the fm inertial sensor
US10809280B2 (en) 2017-08-30 2020-10-20 Stmicroelectronics S.R.L. FM inertial sensor and method for operating the FM inertial sensor

Also Published As

Publication number Publication date
CA2282510A1 (en) 1998-08-27
EP0970349A1 (en) 2000-01-12
US5911156A (en) 1999-06-08
EP0970349B1 (en) 2005-08-10
DE69831143D1 (en) 2005-09-15
JP4458441B2 (en) 2010-04-28
JP2001513885A (en) 2001-09-04
DE69831143T2 (en) 2006-04-20
EP0970349A4 (en) 2003-03-26

Similar Documents

Publication Publication Date Title
EP0970349B1 (en) Tuning fork gyro with split electrode
US7213458B2 (en) Quadrature reduction in MEMS gyro devices using quad steering voltages
US7231824B2 (en) Use of electrodes to cancel lift effects in inertial sensors
US8087295B2 (en) Dual-axis resonator gyroscope
US5747690A (en) Vibratory microgyroscope
US6250156B1 (en) Dual-mass micromachined vibratory rate gyroscope
US5992233A (en) Micromachined Z-axis vibratory rate gyroscope
US5392650A (en) Micromachined accelerometer gyroscope
US6742390B2 (en) Angular velocity sensor
US6230563B1 (en) Dual-mass vibratory rate gyroscope with suppressed translational acceleration response and quadrature-error correction capability
US5892153A (en) Guard bands which control out-of-plane sensitivities in tuning fork gyroscopes and other sensors
US6715353B2 (en) MEMS gyroscope with parametric gain
US20050268716A1 (en) Built in test for mems vibratory type inertial sensors
US7325451B2 (en) Oscillating micro-mechanical sensor of angular velocity
US7426861B2 (en) Tuning fork gyroscopes, accelerometers, and other sensors with improved scale factor
US6621279B2 (en) Drive feedthrough nulling system
EP3249356B1 (en) Systems and methods for a four-mass vibrating mems structure
US6089088A (en) Vibrating microgyrometer
US20130055787A1 (en) Coriolis gyroscope having correction units and method for reducing the quadrature bias
US5747961A (en) Beat frequency motor position detection scheme for tuning fork gyroscope and other sensors
KR101093883B1 (en) Microelectromechanical sensor and operating method for a microelectromechanical sensor
EP1914511B1 (en) Tuning fork gyro with sense plate read-out
US6064169A (en) Motor amplitude control circuit in conductor-on-insulator tuning fork gyroscope
US10330475B2 (en) Segmented electrode structure for quadrature reduction in an integrated device

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1998906689

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2282510

Country of ref document: CA

Ref country code: CA

Ref document number: 2282510

Kind code of ref document: A

Format of ref document f/p: F

ENP Entry into the national phase

Ref country code: JP

Ref document number: 1998 536990

Kind code of ref document: A

Format of ref document f/p: F

WWP Wipo information: published in national office

Ref document number: 1998906689

Country of ref document: EP

WWG Wipo information: grant in national office

Ref document number: 1998906689

Country of ref document: EP