Method for electronically tuning the readout vibration of a coriolis gyroscope

• US 7,337,665 B2
• Filed: 10/02/2003
• Issued: 03/04/2008
• Est. Priority Date: 10/18/2002
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Litef GmbH (Northrop Grumman Corporation)
• Inventors: Schroeder, Werner
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US10/531,669
• Publication Number:
  US 20060010999A1
• Time in Patent Office: 1,615 Days
• Field of Search: 735/040.2, 735/040.4, 735/041.2, 735/041.3, 735/041.4, 735/041.5, 735/041.6, 73/13.7, 73/13.8
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: Y10T 74/1229 Gyroscope control

Abstract

In a method for electronic tuning of the frequency of the read oscillation to the frequency of the stimulation oscillation in a Coriolis gyro, the resonator of the Coriolis gyro has a disturbance force applied to it such that the stimulation oscillation remains essentially uninfluenced. The read oscillation is changed so that a read signal that represents the read oscillation contains a corresponding disturbance component. The frequency of the read oscillation is controlled so that the magnitude of the disturbance component contained in the read signal is a minimum.

Claims

1. A method for electronic tuning of a frequency of a read oscillation to a frequency of a stimulation oscillation in a Coriolis gyro, wherein

a resonator of the Coriolis gyro has a disturbance force applied to the resonator such that

a) the stimulation oscillation remains essentially uninfluenced, and

b) the read oscillation is changed such that a read signal, which represents the read oscillation, contains a corresponding disturbance component, wherein

the frequency of the read oscillation is controlled such that a magnitude of the disturbance component, which is contained in the read signal, is as small as possible.

2. The method as claimed in claim 1, characterized in that the disturbance force is produced by a disturbance signal which is added to respective control/reset signals for control/compensation of the read oscillation.

3. The method as claimed in claim 1, characterized in that a disturbance signal is an alternating signal.

4. The method as claimed in claim 3, characterized in that a disturbance signal is at a fixed disturbance frequency, and the disturbance component is determined from the read signal by demodulation of the read signal at the fixed disturbance frequency.

5. The method as claimed in claim 1, characterized in that a disturbance signal is band-limited noise, and the disturbance component is demodulated from the read signal by correlation of the disturbance signal with the read signal.

6. The method as claimed in claim 2, characterized in that the disturbance signal is added to the output signal from a rotation rate control loop, and the disturbance component is determined from a signal which is applied to a quadrature regulator in a quadrature control loop, or is emitted from the quadrature regulator in the quadrature control loop.

7. The method as claimed in claim 2, characterized in that the disturbance signal is added to an output signal from a quadrature control loop, and the disturbance component is determined from a signal which is applied to a rotation rate regulator in a rotation rate control loop, or is emitted from the rotation rate regulator in the rotation control loop.

8. The method as claimed in claim 2, characterized in that the disturbance signal is added to an output signal from a quadrature control loop, and the disturbance component is determined from a signal which is applied to a quadrature regulator in a quadrature control loop, or is emitted from the quadrature regulator in the quadrature control loop.

9. The method as claimed in claim 2, characterized in that the disturbance signal is added to an output signal from a rotation rate control loop, and the disturbance component is determined from a signal which is applied to a rotation rate regulator in a rotation rate control loop, or is emitted from the rotation rate regulator in the rotation rate control loop.

10. The method as claimed in claim 2, characterized in that the frequency of the read oscillation is controlled by controlling an intensity of an electrical field in which a part of the resonator of the Coriolis gyro oscillates.

11. A Coriolis gyro which has a rotation rate control loop and a quadrature control loop, characterized by a device for electronic tuning of a frequency of a read oscillation to a frequency of a stimulation oscillation, having:

a disturbance unit which passes a disturbance signal to the rotation rate control loop or to the quadrature control loop,

a disturbance signal detection unit, which determines a disturbance component which is contained in a read signal which represents the read oscillation and has been produced by the disturbance signal, and

a control unit, which controls the frequency of the read oscillation such that a magnitude of the disturbance component, which is contained in the read signal, is as small as possible.

12. The Coriolis gyro as claimed in claim 11, characterized in that the disturbance unit passes the disturbance signal to the rotation rate control loop, and the disturbance signal detection unit determines the disturbance component from a signal which is applied to a quadrature regulator in the quadrature control loop, or is emitted from the quadrature regulator in the quadrature control loop.

13. The Coriolis gyro as claimed in claim 11, characterized in that the disturbance unit passes the disturbance signal to the quadrature control loop, and the disturbance signal detection unit determines the disturbance component from a signal which is applied to a rotation rate regulator in the rotation rate control loop, or is emitted from the rotation rate regulator in the rotation rate control loop.

14. The Coriolis gyro as claimed in claim 11, characterized in that the disturbance unit passes the disturbance signal to the rotation rate control loop, and the disturbance signal detection unit determines the disturbance component from a signal which is applied to a rotation rate regulator in the rotation rate control loop, or is emitted from the rotation rate regulator in the rotation rate control loop.

15. The Coriolis gyro as claimed in claim 11, characterized in that the disturbance unit passes the disturbance signal to the quadrature control loop, and the disturbance signal detection unit determines the disturbance component from a signal which is applied to a quadrature regulator in the quadrature control loop, or is emitted from the quadrature regulator in the quadrature control loop.

16. The Coriolis gyro as claimed in claim 11, characterized in that the disturbance signal is an alternating signal at a fixed disturbance frequency, and the device for electronic tuning of the read oscillation frequency and stimulation oscillation frequency has a demodulation unit, which demodulates the read signal at the fixed disturbance frequency and thus determines the disturbance component which is contained in the read signal.