Multi-axis micro gyro structure

• US 6,578,420 B1
• Filed: 06/26/2000
• Issued: 06/17/2003
• Est. Priority Date: 01/28/1997
• Status: Expired due to Term

• Current Assignee: Hanger Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Microsensors Incorporated
• Inventors: Hsu, Ying Wen
• Primary Examiner(s): MOLLER, RICHARD ALAN
• Application Number:
  US09/604,782
• Time in Patent Office: 1,086 Days
• Field of Search: 735/041.6, 735/041.5, 735/041.2, 735/040.2
• US Class Current: 73/504.16
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis

Abstract

A three-axis micro-gyro structure having first and second micro-gyro devices that measure angular velocity around first and second rate axes extending in a plane of the micro-gyro structure and a third micro-gyro that measures angular velocity around a third rate axis perpendicular to the plane of the micro-gyro structure.

Claims

1. A unitary three-axis micro-gyro structure that comprises:

a monolithic substrate that defines a plane of the micro-gyro, and

three micro-gyro devices formed simultaneously as a layer on the substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material,

the first micro-gyro device being so constructed as to measure angular velocity of the micro-gyro structure around a first rate axis extending in the plane of the micro-gyro,

the second micro-gyro device being so constructed as to measure angular velocity of the micro gyro structure around a second rate axis extending in the plane of the micro-gyro and perpendicular to the first rate axis; and

the third micro-gyro device being so constructed as to measure angular velocity of the micro-gyro structure around a third rate axis perpendicular to the plane of the micro-gyro.

2. The unitary three-axis micro-gyro structure of claim 1 in which each micro-gyro device comprises:

a first momentum creating element formed as an outer element having an open center, and

a second Coriolis sensing element formed as an inner element located in said center.

3. A three-axis micro-gyro structure of planar construction comprising:

first and second micro-gyro devices that measure angular velocity around first and second rate axes extending in the plane of the micro-gyro structure; and

a third micro-gyro device that measures angular velocity around a third rate axis perpendicular to the plane of the micro-gyro structure.

4. The three-axis micro-gyro structure of claim 3 wherein the first and second micro-gyro devices are of substantially identical construction and the third micro-gyro device is of substantially different construction.

5. The three-axis micro-gyro structure of claim 3 wherein the first and second micro-gyro devices are oriented orthogonally relative to one another in the plane of the micro-gyro structure.

6. The three-axis micro-gyro structure of claim 3 wherein the first, second and third micro-gyro devices are substantially planar and wherein the first, second and third micro-gyro devices are arranged in a planar field such that the three-axis micro-gyro structure has a substantially planar configuration.

7. The three-axis micro-gyro structure of claim 3 further comprising a planar substrate that supports the first, second and third micro-gyro devices.

8. The three-axis micro-gyro structure of claim 7 wherein the three micro-gyro devices are formed simultaneously as a layer on the substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

9. The three-axis micro-gyro structure of claim 8 wherein the substrate is a silicon substrate.

10. The three-axis micro-gyro structure of claim 8 wherein the substrate is a quartz substrate.

11. The three-axis micro-gyro structure of claim 8 wherein the substrate is an alumina substrate.

12. The three-axis micro-gyro of claim 7 wherein the first, second and third micro-gyro devices are individually-formed devices that are individually mounted on the planar substrate.

13. The three-axis micro-gyro of claim 12 wherein the planar substrate comprises a printed circuit board (PCB).

14. The three-axis micro-gyro structure of claim 7 wherein the planar substrate is an integrated circuit.

15. The three-axis micro-gyro structure of claim 7 wherein the planar substrate is a package base.

16. The three-axis micro-gyro of claim 15 wherein the first, second and third micro-gyro devices are mounted on the package base.

17. The three-axis micro-gyro of claim 16 wherein the first, second and third micro-gyro devices are individually-formed devices that are individually mounted on the package base.

18. The three-axis micro-gyro of claim 16 wherein the first and second micro-gyro devices are formed on a common intermediate substrate.

19. The three-axis micro-gyro of claim 18 wherein the first and second micro-gyro devices are simultaneously formed on the common intermediate substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

20. The three-axis micro-gyro of claim 18 wherein the common intermediate substrate is a silicon substrate.

21. The three-axis micro-gyro structure of claim 18 wherein the common intermediate substrate is a quartz substrate.

22. The three-axis micro-gyro structure of claim 18 wherein the common intermediate substrate is an alumina substrate.

23. The three-axis micro-gyro of claim 16 wherein the first, second and third micro-gyro devices are formed on a common intermediate substrate.

24. The three-axis micro-gyro of claim 23 wherein the first, second and third micro-gyro devices are simultaneously formed on the common intermediate substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

25. The three-axis micro-gyro of claim 23 wherein the common intermediate substrate is a silicon substrate.

26. The three-axis micro-gyro structure of claim 23 wherein the common intermediate substrate is a quartz substrate.

27. The three-axis micro-gyro structure of claim 23 wherein the common intermediate substrate is an alumina substrate.

28. A three-axis micro-gyro structure of planar construction comprising:

first and second micro-gyro devices that are substantially identical in construction,

the first and second micro-gyro devices being constructed as to measure angular velocity of the micro-gyro structure around first and second rate axes extending in the plane of the micro-gyro structure,

the first and second micro-gyro devices being oriented relative to one another in a plane of the micro-gyro structure to position the second rate axis perpendicular to the first rate axis; and

a third micro-gyro device being constructed as to measure angular velocity of the micro-gyro structure around a third rate axis perpendicular to the plane of the micro-gyro structure.

29. The three-axis micro-gyro structure of claim 28 further comprising a monolithic substrate that supports the first, second and third micro-gyro devices in the plane of the micro-gyro structure.

30. The three-axis micro-gyro of claim 29 wherein the first and second micro-gyro devices are simultaneously formed on the monolithic substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

31. The three-axis micro-gyro of claim 30 wherein the monolithic substrate is a silicon substrate.

32. The three-axis micro-gyro structure of claim 30 wherein the monolithic substrate is a quartz substrate.

33. The three-axis micro-gyro structure of claim 30 wherein the monolithic substrate is an alumina substrate.

34. The three-axis micro-gyro of claim 29 wherein the first, second and third micro-gyro devices are simultaneously formed on the monolithic substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

35. The three-axis micro-gyro of claim 34 wherein the monolithic substrate is a silicon substrate.

36. A three-axis micro-gyro structure comprising:

a planar substrate;

a first micro-gyro device supported by the planar substrate and constructed as to measure angular velocity around a first rate axis extending in the plane of the substrate,

a second micro-gyro device supported by the planar substrate and constructed as to measure angular velocity around a second rate axis extending in the plane of the substrate and perpendicular to the first rate axis; and

a third micro-gyro device supported by the planar substrate and constructed as to measure angular velocity of the micro-gyro structure around a third rate axis perpendicular to the plane of the substrate.

37. The three-axis micro-gyro structure of claim 36 wherein the planar substrate is a silicon substrate, and wherein the three micro-gyro devices are formed simultaneously as a layer on the silicon substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

38. The three-axis micro-gyro structure of claim 36 wherein the planar substrate is an integrated circuit.

39. The three-axis micro-gyro of claim 36 wherein the first, second and third micro-gyro devices are individually-formed devices that are individually mounted on the planar substrate.

40. The three-axis micro-gyro of claim 39 wherein the planar substrate comprises a printed circuit board (PCB).

41. The three-axis micro-gyro structure of claim 36 wherein the planar substrate is a package base.

42. The three-axis micro-gyro of claim 41 wherein the first, second and third micro-gyro devices are mounted on the package base.

43. The three-axis micro-gyro of claim 42 wherein the first, second and third micro-gyro devices are individually-formed devices that are individually mounted on the package base.

44. The three-axis micro-gyro of claim 42 wherein the first and second micro-gyro devices are formed on a common intermediate substrate.

45. The three-axis micro-gyro of claim 44 wherein the first and second micro-gyro devices are simultaneously formed on the common intermediate substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

46. The three-axis micro-gyro of claim 44 wherein the common intermediate substrate is a silicon substrate.

47. The three-axis micro-gyro of claim 42 wherein the first, second and third micro-gyro devices are formed on a common intermediate substrate.

48. The three-axis micro-gyro of claim 47 wherein the first, second and third micro-gyro devices are simultaneously formed on the common intermediate substrate by successive steps of depositing material, delineating desired material shapes by lithography, and etching to remove unwanted material.

49. The three-axis micro-gyro of claim 47 wherein the common intermediate substrate is a silicon substrate.

50. A method of measuring angular velocity about three orthogonal axes comprising the steps of:

providing first, second and third micro-gyros on a planar substrate;

orienting the first micro-gyro to measure angular velocity about a first axis parallel to the substrate;

orienting the second micro-gyro to measure angular velocity about a second axis perpendicular to the first axis and parallel to the substrate; and

orienting the third micro-gyro to measure angular velocity about a third axis perpendicular to the substrate.

51. The method of claim 50 wherein the providing steps comprises the substep of simultaneously forming the first, second and third micro-gyros onto the planar substrate.

52. The method of claim 50 wherein the providing steps comprises the substeps of pre-forming the first, second and third micro-gyros, packaging the pre-formed micro-gyros, and then mounting the packaged, pre-formed micro-gyros onto the planar substrate.