High aspect ratio positioning system

• US 9,303,971 B1
• Filed: 12/15/2010
• Issued: 04/05/2016
• Est. Priority Date: 12/15/2010
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Butscher, Stephen T., Atmur, Robert J., Truncale, Angelo, Justin, Joseph E., Williams, Thomas C.
• Primary Examiner(s): Ho, Ha D
• Assistant Examiner(s): Agendia, Jude
• Application Number:
  US12/968,669
• Time in Patent Office: 1,938 Days
• Field of Search: 74/56.B, 74/56.D, 74/56.E, 74/54.6, 74/54.7
• US Class Current: 1/1
• CPC Class Codes: G01B 7/003 for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G01B 7/30 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01C 19/24 using magnetic or electrostatic fields
• CPC Class Codes: G01D 5/2046 by a movable ferromagnetic element, e.g. a core

Abstract

High aspect ratio positioning systems are disclosed herein. A high aspect ratio positioning system can be packaged in a thin package that can eliminate some bulky components typically associated with positioning systems such as pancake motors or other motors, geared resolvers, gear trains, and the like. Thus, the high aspect ratio positioning system can be used in applications where volume is limited, without sacrificing accuracy.

Claims

1. A high aspect ratio positioning system comprising:

a support surface;

a motor having a circular configuration and disposed adjacent the support surface, the motor comprising

a motor coil assembly attached to an outer magnetic layer that defines an outer diameter of the motor,

a commutation coil assembly and a ring of magnets disposed adjacent an inner magnetic layer that defines an inside diameter of the motor; and

two resolvers adjacent the motor, wherein a first of the two resolvers comprises a first coil having a first number of windings, and wherein a second of the two resolvers comprises a second coil having a second number of windings, the second number being one less than the first number.

2. The high aspect ratio positioning system of claim 1, wherein at least one of the outer magnetic layer and the inner magnetic layer are formed from ferritic steel.

3. The high aspect ratio positioning system of claim 1, further comprising a gap between the motor coil assembly and the commutation coil assembly.

4. The high aspect ratio positioning system of claim 1, wherein the ring of magnets comprises a ring of rare earth magnets.

5. The high aspect ratio positioning system of claim 4, wherein the ring of rare earth magnets are attached to the inner layer.

6. The high aspect ratio positioning system of claim 1, wherein at least one of the two resolvers comprises an inner resolver coil and an outer resolver coil.

7. The high aspect ratio positioning system of claim 6, wherein the inner resolver coil comprises a coil formed from a conductive material.

8. The high aspect ratio positioning system of claim 7, wherein the coil is encased in a flexible material.

9. The high aspect ratio positioning system of claim 8, wherein the flexible material comprises KAPTON.

10. The high aspect ratio positioning system of claim 7, wherein the outer resolver coil comprises two coils formed from the conductive material, and wherein the two coils are encased in a flexible material.

11. The high aspect ratio positioning system of claim 1, wherein the support surface comprises a spherical surface.

12. The high aspect ratio positioning system of claim 11, wherein the motor coil assembly and the two resolvers are disposed proximate to a largest diameter of the support surface.

13. The high aspect ratio positioning system of claim 12, wherein the largest diameter of the support surface is between four inches and six inches.

14. The high aspect ratio positioning system of claim 12, wherein the largest diameter of the support surface is between two inches and twelve inches.

15. An inertial measurement unit comprising:

a set of spherical gimbals comprising an outer sphere and an innermost sphere, the innermost sphere comprising a support surface;

a motor having a circular configuration and disposed adjacent the support surface, the motor comprising a motor coil assembly attached to an outer magnetic layer that defines an outer diameter of the motor, a commutation coil assembly, and a ring of magnets disposed adjacent an inner magnetic layer that defines an inside diameter of the motor; and

two resolvers adjacent the motor, wherein a first of the two resolvers comprises a first coil having a first number of windings, and wherein a second of the two resolvers comprises a second coil having a second number of windings, the second number being one less than the first number.

16. The inertial measurement unit of claim 15, further comprising a gap between the motor coil assembly and the commutation coil assembly.

17. The inertial measurement unit of claim 15, wherein the ring of magnets comprises a plurality of rare earth magnets arranged in a ring, wherein the plurality of rare earth magnets are attached to the inner layer.

18. The inertial measurement unit of claim 15, wherein each of the two resolvers comprises an inner resolver coil and an outer resolver coil.

19. The inertial measurement unit of claim 18, wherein the outer resolver coil comprises two coils formed from a conductive material, each of the two coils being encased in a flexible material.

20. The inertial measurement unit of claim 18, wherein each of the inner resolver coils and the outer resolver coils comprises a coil formed from the conductive material.

21. The inertial measurement unit of claim 20, wherein each of the coils is encased in the flexible material.

22. The inertial measurement unit of claim 15, further comprising an interface for communicating with a computing system in communication with the inertial measurement unit.

23. The inertial measurement unit of claim 22, wherein the computing system comprises a system of an operating environment for the inertial measurement unit.

24. The inertial measurement unit of claim 23, wherein the operating environment comprises a vehicle.

25. The inertial measurement unit of claim 24, wherein the vehicle comprises an aircraft, and the computing system comprises an avionics system of the aircraft.

26. The inertial measurement unit of claim 24, wherein the vehicle comprises a watercraft.

27. The inertial measurement unit of claim 24, wherein the vehicle comprises a spacecraft.

28. A spherical gimbal set comprising:

an outer sphere;

an innermost sphere comprising a support surface; and

a high aspect ratio positioning system disposed proximate to the support surface, the high aspect ratio positioning system comprising

a motor having a circular configuration and disposed adjacent the support surface, the motor comprising a motor coil assembly attached to an outer magnetic layer that defines an outer diameter of the motor, a commutation coil assembly, and a ring of magnets disposed adjacent an inner magnetic layer that defines an inside diameter of the motor, and

two resolvers adjacent the motor, wherein a first of the two resolvers comprises a first coil having a first number of windings, and wherein a second of the two resolvers comprises a second coil having a second number of windings, the second number being one less than the first number.

29. The spherical gimbal set of claim 28, wherein the outer sphere comprises two flanges configured to connect the outer sphere to a support such that the outer sphere is allowed to rotate about a rotational axis concentric with a center of the flanges.

30. The spherical gimbal set of claim 29, wherein the outer sphere further comprises two inner flanges configured to connect to two innermost flanges of an innermost sphere, the innermost sphere being supported by the outer sphere such that the innermost sphere is allowed to rotate about a second rotational axis.

31. The spherical gimbal set of claim 28, wherein the ring of magnets comprises a ring of rare earth magnets attached to the inner layer.

32. The spherical gimbal set of claim 28, wherein the first number of windings are formed from a conductive material and encased in a flexible material, and wherein the second number of windings are formed from the conductive material and encased in the flexible material.

33. The spherical gimbal set of claim 32, wherein the conductive material comprises copper, and the flexible material comprises KAPTON.

34. The spherical gimbal set of claim 28, wherein the innermost sphere is formed from aluminum.

35. A vehicle comprising an inertial measurement unit configured to track orientation of the vehicle, the inertial measurement unit comprising:

a set of spherical gimbals comprising an innermost sphere, the innermost sphere comprising a support surface;

a motor having a circular configuration and disposed adjacent the support surface, the motor comprising a motor coil assembly attached to an outer magnetic layer that defines an outer diameter of the motor, a commutation coil assembly, a gap between the motor coil assembly and the commutation coil assembly, and a plurality of magnets arranged in a ring, the magnets being disposed adjacent an inner magnetic layer that defines an inside diameter of the motor; and

two resolvers adjacent the motor, wherein each of the two resolvers comprises an inner resolver coil and an outer resolver coil, wherein a first of the two resolvers comprises a first coil having a first number of windings, and wherein a second of the two resolvers comprises a second coil having a second number of windings, the second number being one less than the first number.

36. The vehicle of claim 35, wherein the first number of windings are formed from copper and encased in KAPTON, and wherein the second number of windings are formed from copper and encased in the KAPTON.

37. The vehicle of claim 36, wherein the vehicle further comprises a warhead and an engine for delivering the warhead.

38. A method for sensing movement of a structure, the method comprising:

receiving a data signal generated by a high aspect ratio positioning system in response to movement of the structure;

determining if movement of the structure has ceased; and

in response to determining that movement of the structure has not ceased, monitoring the high aspect ratio positioning system for another data signal, wherein the high aspect ratio positioning system comprises;

a support surface;

a motor having a circular configuration and disposed adjacent the support surface, the motor comprising a motor coil assembly attached to an outer magnetic layer that defines an outer diameter of the motor, a commutation coil assembly, and a ring of magnets disposed adjacent an inner magnetic layer that defines an inside diameter of the motor; and

two resolvers adjacent the motor, wherein a first of the two resolvers comprises a first coil having a first number of windings, and wherein a second of the two resolvers comprises a second coil having a second number of windings, the second number being one less than the first number.

39. The method of claim 38, wherein the data signal comprises data indicating movement of the resolvers.

40. The method of claim 38, wherein the positioning system comprises an inertial measurement unit.