Micro rate of rotation sensor and method for operating a micro rate of rotation sensor

• US 9,151,611 B2
• Filed: 12/19/2012
• Issued: 10/06/2015
• Est. Priority Date: 12/28/2011
• Status: Active Grant

• Current Assignee: Hanking Electronics Hongkong Company Limited
• Original Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Inventors: Coronato, Luca, Cazzaniga, Gabriele
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US13/720,426
• Publication Number:
  US 20130167636A1
• Time in Patent Office: 1,021 Days
• Field of Search: 735/041.2, 735/041.4, 735/040.4, 735/040.2
• US Class Current: 1/1
• CPC Class Codes: G01C 19/42 for indicating rate of turn; for integrating rate of turn
• CPC Class Codes: G01C 19/5642 using vibrating bars or beams
• CPC Class Codes: G01C 19/5712 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames

Abstract

The present invention relates to a method for operating a rotation sensor for detecting a plurality of rates of rotation about orthogonal axes (x,y,z). The rotation sensor comprises a substrate, driving masses, X-Y sensor masses, and Z sensor masses. The driving masses are driven by drive elements to oscillate in the X-direction. The X-Y sensor masses are coupled to the driving masses, and driven to oscillate in the X-Y direction radially to a center. When a rate of rotation of the substrate occurs about the X-axis or the Y-axis, the X-Y sensor masses are jointly deflected about the Y-axis or X-axis. When a rate of rotation of the substrate occurs about the Z-axis, the X-Y sensor masses are rotated about the Z-axis, and the Z sensor masses are deflected substantially in the X-direction.

Claims

1. A rotation sensor for detecting a plurality of rates of rotation about orthogonal axes (x,y,z), comprising:

a substrate;

a plurality of masses that are displaceable relative to the substrate and disposed in an X-Y plane parallel to the substrate;

a plurality of anchors for coupling the plurality of masses to the substrate;

springs to couple at least some of the plurality of masses to at least one adjacent mass or to at least one anchor;

drive elements for oscillating more than one of the plurality of masses in an X-direction, in order to generate Coriolis forces when the substrate is deflected;

sensor elements in order to detect deflections of the more than one of the plurality of masses due to the Coriolis forces generated; and

wherein the plurality of masses include driving masses, X-Y sensor masses. and Z sensor masses, the X-Y sensor masses being coupled to the driving masses and the Z sensor masses by means of springs, the X-Y sensor masses and the driving masses being coupled in such a manner that when the driving masses are driven to oscillate in the X-direction, the X-Y sensor masses are driven to oscillate in an X-Y direction by means of the driving masses.

2. The rotation sensor according to claim 1, wherein a drive direction of the X-Y sensor masses, the X-Y direction, is provided between the X-axis and the Y-axis in the X-Y plane at an angle of 45°

to the X-axis.

3. The rotation sensor according to claim 1, wherein the X-Y sensor masses are disposed about a central suspension that includes at least one central anchor.

4. The rotation sensor according to claim 1, wherein the X-Y sensor masses are driven to oscillate radially or offset from a center by the driving masses oscillating in the X-direction.

5. The rotation sensor according to claim 3, wherein an elastic attachment configured as a gimbal suspension having axes of rotation about the X-axis, Y-axis, and Z-axis disposed between the X-Y sensor masses and the central suspension.

6. The rotation sensor according to claim 5, wherein the elastic gimbal suspension comprises two rings coupled to each other by means of torsional springs offset from each other.

7. The rotation sensor according to claim 6, wherein each X-Y sensor mass is displaceably coupled to a outer ring of the gimbal suspension in a drive direction of the X-Y sensor mass but not displaceably with respect to motions of the X-Y sensor mass out of the X-Y plane.

8. The rotation sensor according to claim 1, wherein the X-Y sensor masses are coupled to the Z sensor masses by means of springs, such that when an oscillating motion of the X-Y sensor masses occurs in the X-Y direction and about the Z-axis, the Z sensor masses oscillate in the X-Y plane substantially in the X-direction.

9. The rotation sensor according to claim 1, wherein the X-Y sensor masses are coupled to the Z sensor masses by means of springs, such that when an oscillating motion of the X-Y sensor masses occurs in the X-Y direction, the Z sensor masses are substantially stationary, and when an oscillating rotary motion of the X-Y sensor masses occurs about the Z-axis, the Z sensor masses oscillate substantially in the X-direction.

10. The rotation sensor according to claim 1, wherein synchronization springs are disposed between the X-Y sensor masses.

11. The rotation sensor according to claim 1, wherein each of the X-Y sensor masses is coupled to at least one driving mass and to one Z-sensor mass by means of springs.

12. The rotation sensor according to claim 1, wherein at least one of the driving masses and the Z sensor masses is disposed on at least one anchors by means of springs.

13. The rotation sensor according to claim 1, wherein two driving masses or pairs of driving masses are provided.

14. The rotation sensor according to claim 13, wherein the driving masses of a pair of driving masses are coupled to each other by means of connecting elements.

15. The rotation sensor according to claim 1, wherein the drive elements are electrodes for driving the driving masses.

16. The rotation sensor according to claim 1, wherein the sensor elements are associated with at least one of the X-Y sensor masses and the Z sensor masses.

17. A method for operating a rotation sensor for detecting a plurality of rates of rotation about orthogonal axes (x,y,z), comprising the steps of:

arranging on a substrate driving masses, X-Y sensor masses, and Z sensor masses;

driving the driving masses by drive elements to oscillate in an X-direction;

driving the X-Y sensor masses to oscillate in the X-Y direction radially to a center by a connection to the driving masses; and

sensing a response of at least one of X-Y and Z sensor masses according to a rate of rotation of the substrate, wherein when the rate of rotation of the substrate occurs about the X-axis or the Y-axis, the X-Y sensor masses are jointly deflected-about the Y-axis or X-axis, and when the rate of rotation of the substrate occurs about the Z-axis, the X-Y sensor masses are rotated about the Z-axis, and the Z sensor masses are deflected substantially in the X-direction.

18. The method according to claim 17, wherein the X-Y sensor masses are driven to oscillate radially to a central suspension by the driving masses oscillating in the X-direction.