Yaw rate gyroscope robust to linear and angular acceleration

• US 10,359,284 B2
• Filed: 08/09/2016
• Issued: 07/23/2019
• Est. Priority Date: 12/10/2015
• Status: Active Grant

• Current Assignee: Invensense Incorporated (TDK Corporation)
• Original Assignee: Invensense Incorporated (TDK Corporation)
• Inventors: Coronato, Luca, Gafforelli, Giacomo, Ruohio, Jaakko
• Primary Examiner(s): West, Paul M.
• Assistant Examiner(s): Shabman, Mark A
• Application Number:
  US15/232,463
• Publication Number:
  US 20170234684A1
• Time in Patent Office: 1,078 Days
• Field of Search: None
• CPC Class Codes: G01C 19/5726 Signal processing
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames

Abstract

A gyroscope includes four drive masses and four sense masses. Each drive mass is adjacent to two other drive masses and opposite the fourth drive mass, and each sense mass is adjacent to two other sense masses and opposite the fourth sense mass. Each drive mass may oscillate in a manner that is perpendicular to its adjacent drive mass and parallel and anti-phase to its opposite mass. The sense motion of the each sense mass may be coupled in a manner that prevents motion due to linear acceleration or angular acceleration.

Claims

1. A gyroscope, comprising:

four drive masses, wherein each of the four drive masses oscillate in a first plane, wherein a first drive mass is located adjacent to a second drive mass and a fourth drive mass, and opposite a third drive mass, wherein the second drive mass is located adjacent to the first drive mass and the third drive mass, and opposite the fourth drive mass, wherein the third drive mass is located adjacent to the second drive mass and the fourth drive mass, and opposite the first drive mass, and wherein the fourth drive mass is located adjacent to the third drive mass and the first drive mass and opposite the second drive mass;

one or more drive electrodes, wherein the one or more drive electrodes cause the first drive mass and the third drive mass to oscillate along parallel axes and in anti-phase, and wherein the one or more drive electrodes cause the second drive mass and the fourth drive mass to oscillate along parallel axes and anti-phase, and wherein the oscillations of the first drive mass and the third drive mass are perpendicular to the oscillations of the second drive mass and the fourth drive mass;

four sense masses, wherein each of the four sense masses is associated with a respective one of the four drive masses, wherein each of the four sense masses moves in a sense axis in response to a Coriolis force caused by the rotation of the gyroscope, and wherein the sense axis for each of the four sense masses is in the first plane and perpendicular to the oscillation of the associated drive mass and the axis of rotation of the gyroscope; and

a plurality of sense coupling links, wherein each of the sense masses is pivotally coupled to two of the other sense masses by one or more of the plurality of sense coupling links, wherein the plurality of sense coupling links comprise four coupling links, wherein a first coupling link pivotally couples the first sense mass to the second sense mass, wherein a second coupling link pivotally couples the second sense mass to the third sense mass, wherein a third coupling link pivotally couples the third sense mass to a fourth sense mass, and wherein a fourth coupling link pivotally couples the fourth sense mass to the first sense mass.

2. The gyroscope of claim 1, wherein the first and the second drive mass move towards and away from a first point, wherein the second and the third drive mass move towards and away from a second point, wherein the third and the fourth drive mass move towards and away from a third point, and wherein the fourth and the first drive mass move towards and away from a fourth point.

3. The gyroscope of claim 2, wherein the first and the second drive mass move towards the first point when the third and the fourth drive mass move towards the third point, and wherein the fourth and the first drive mass move towards the fourth point when the second and the third drive mass move towards the second point.

4. The gyroscope of claim 1, wherein the gyroscope is balanced with respect to linear acceleration and angular acceleration.

5. The gyroscope of claim 1, wherein the four sense coupling links cause the first sense mass and the third sense mass to move in parallel and in anti-phase, cause the second sense mass and fourth sense mass to move in parallel and in anti-phase, and cause the first sense mass and the third sense mass move perpendicular to the second sense mass and the fourth sense mass.

6. The gyroscope of claim 1, wherein the four sense coupling links cause the first sense mass and the third sense mass to simultaneously move towards or away from a center point of the gyroscope in response to the Coriolis force, cause the second sense mass and the fourth sense mass to simultaneously move towards or away from the center point of the gyroscope the Coriolis force, and wherein the first sense mass and third sense mass move along an opposite axis relative to the center point of the gyroscope than the second sense mass and the fourth sense mass.

7. The gyroscope of claim 1, further comprising four drive coupling links, wherein a first drive coupling link couples the first drive mass to the second drive mass, a second drive coupling link couples the second drive mass to the third drive mass, a third drive coupling link couples the third drive mass to the fourth drive mass, and wherein a fourth coupling link couples the fourth drive mass to the first drive mass.

8. The gyroscope of claim 7, wherein each of the four drive coupling links comprises a drive lever to pivotally couple the respective drive masses to each other.

9. The gyroscope of claim 1, further comprising:

a first Coriolis mass coupled to the first drive mass and the first sense mass;

a second Coriolis mass coupled to the second drive mass and the second sense mass;

a third Coriolis mass coupled to the third drive mass and the third sense mass; and

a fourth Coriolis mass coupled to the fourth drive mass and the fourth sense mass.

10. The gyroscope of claim 9, further comprising:

a first drive spring coupling the first Coriolis mass to the first drive mass, wherein the first drive spring is rigid in the axis of the oscillation of the first drive mass and flexible in the axis of the Coriolis force of the first sense mass;

a first sense spring coupling the first Coriolis mass to the first sense mass, wherein the first sense spring is rigid in the axis of the Coriolis force of the first sense mass;

a second drive spring coupling the second Coriolis mass to the second drive mass, wherein the second drive spring is rigid in the axis of the oscillation of the second drive mass and flexible in the axis of the Coriolis force of the second sense mass;

a second sense spring coupling the second Coriolis mass to the second sense mass, wherein the second sense spring is rigid in the axis of the Coriolis force of the second sense mass;

a third drive spring coupling the third Coriolis mass to the third drive mass, wherein the third drive spring is rigid in the axis of the oscillation of the third drive mass and flexible in the axis of the Coriolis force of the third sense mass;

a third sense spring coupling the third Coriolis mass to the third sense mass, wherein the third sense spring is rigid in the axis of the Coriolis force of the third sense mass;

a fourth drive spring coupling the fourth Coriolis mass to the fourth drive mass, wherein the fourth drive spring is rigid in the axis of the oscillation of the fourth drive mass and flexible in the axis of the Coriolis force of the fourth sense mass; and

a fourth sense spring coupling the fourth Coriolis mass to the fourth sense mass, wherein the fourth sense spring is rigid in the axis of the Coriolis force of the fourth sense mass.

11. The gyroscope of claim 10, wherein the first sense spring is flexible in the axis of the drive force of the first drive mass, wherein the second sense spring is flexible in the axis of the drive force of the second drive mass, wherein the third sense spring is flexible in the axis of the drive force of the third drive mass, and wherein the fourth sense spring is flexible in the axis of the drive force of the fourth drive mass.

12. The gyroscope of claim 1, further comprising:

a first drive spring coupling the first drive mass to the first sense mass, wherein the first drive spring is rigid in the axis of the oscillation of the first drive mass and flexible in the axis of the Coriolis force of the first sense mass;

a second drive spring coupling the second drive mass to the second sense mass, wherein the second drive spring is rigid in the axis of the oscillation of the second drive mass and flexible in the axis of the Coriolis force of the second sense mass;

a third drive spring coupling the third drive mass to the third sense mass, wherein the third drive spring is rigid in the axis of the oscillation of the third drive mass and flexible in the axis of the Coriolis force of the third sense mass; and

a fourth drive spring coupling the fourth drive mass to the fourth sense mass, wherein the fourth drive spring is rigid in the axis of the oscillation of the fourth drive mass and flexible in the axis of the Coriolis force of the fourth sense mass.