Micro inertial measurement system

• US 9,213,046 B2
• Filed: 12/06/2010
• Issued: 12/15/2015
• Est. Priority Date: 08/09/2010
• Status: Active Grant

• Current Assignee: SZ DJI Technology Co., Ltd. (d/b/a DJI) (iFlight Technology Company Limited)
• Original Assignee: SZ DJI Technology Co., Ltd. (d/b/a DJI) (iFlight Technology Company Limited)
• Inventors: Wang, Tao
• Primary Examiner(s): Kwok, Helen
• Application Number:
  US13/809,407
• Publication Number:
  US 20130111993A1
• Time in Patent Office: 1,835 Days
• Field of Search: 734/93, 734/31, 735/10, 735/11, 702/145, 702/151
• US Class Current: 1/1
• CPC Class Codes: F16F 15/022 using dampers and springs in combination
• CPC Class Codes: F16F 15/04 using elastic means single elements or their attachment F16F1/00 - F16F13/00; F16F15/023, F16F15/03 take precedence
• CPC Class Codes: F16F 15/085 Use of both rubber and metal springs
• CPC Class Codes: G01C 19/5783 Mountings or housings not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01C 21/166 Mechanical, construction or arrangement details of inertial navigation systems
• CPC Class Codes: G01P 1/02 Housings
• CPC Class Codes: G01P 15/14 by making use of gyroscopes gyroscopes per se G01C19/00
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

A micro inertial measurement system includes a housing, a sensing module, and a damper. The sensing module includes a rigid sensing support, a measuring and controlling circuit board mounted on the rigid sensing support and an inertial sensor set on the measuring and controlling circuit board. The inertial sensor includes a gyroscope and an accelerometer. The sensing module is mounted in the housing. The damper is mounted in the housing and set in the gap between the sensing module and the inside wall of the housing. By use of the above-mentioned structure, the noise immunity of the inertial measuring system can be greatly improved, and the volume and weight of the inertial measuring system can be greatly reduced.

Claims

1. An inertial measurement device, the device comprising:

a sensing module comprising a support structure and a flexible inertial sensor, wherein the support structure comprises a plurality of external surfaces facing away from one another, and wherein the flexible inertial sensor is configured to wrap around the plurality of external surfaces of the support structure, such that the flexible inertial sensor substantially covers the plurality of external surfaces of the support structure, and wherein the flexible inertial sensor comprises one or more accelerometers and one or more gyroscopes.

2. The device of claim 1, wherein the flexible inertial sensor comprises one accelerometer and three gyroscopes.

3. The device of claim 1, wherein the flexible inertial sensor comprises a front surface configured to support the one or more accelerometers and one or more gyroscopes and a back surface opposite the front surface, and wherein the flexible inertial sensor wraps around the plurality of external surfaces of the support structure with the front surface facing the support structure and the back surface facing away from the support structure.

4. The device of claim 1, wherein the support structure comprises a plurality of grooves and each of the one or more accelerometers and the one or more gyroscopes is received within a respective groove of the plurality of grooves when the flexible inertial sensor is wrapped around the plurality of external surfaces of the support structure.

5. The device of claim 1, further comprising a housing containing therein said sensing module.

6. The device of claim 5, wherein the housing comprises a plurality of separable portions.

7. The device of claim 5, further comprising one or more damping units arranged between the sensing module and the housing.

8. The device of claim 7, wherein the flexible inertial sensor comprises a flexible circuit board, and wherein the one or more accelerometers and the one or more gyroscopes are each coupled to the flexible circuit board.

9. The device of claim 8, wherein the flexible circuit board comprises a plurality of panels, the flexible circuit board being foldable such that at least a subset of the plurality of panels are orthogonal to each other when the flexible circuit board is wrapped around the plurality of external surfaces of the support structure.

10. The device of claim 9, wherein the one or more accelerometers and the one or more gyroscopes are positioned on the plurality of panels such that at least a subset of the one or more accelerometers and the one or more gyroscopes are orthogonal to each other when the flexible circuit board is folded.

11. The device of claim 9, wherein the flexible circuit board comprises six panels and the support structure is a cube-shaped structure comprising six external faces, and wherein each of the six panels substantially covers a corresponding external face of the support structure when the flexible circuit board is folded.

12. The device of claim 11, wherein the one or more damping units comprise six damping units, each of the six damping units being in contact with a corresponding panel of the flexible circuit board.

13. The device of claim 7, wherein the one or more damping units are arranged relative to the sensing module such that an elastic center of the one or more damping units substantially coincides with a centroid of the sensing module.

14. A method for fabricating the inertial measurement device of claim 1, the method comprising:

providing the support structure; and

wrapping the flexible inertial sensor around the plurality of external surfaces of the support structure to substantially cover the plurality of external surfaces of the support structure, thereby forming the sensing module.

15. The method of claim 14, wherein the flexible inertial sensor comprises one accelerometer and three gyroscopes.

16. The method of claim 14, wherein the flexible inertial sensor comprises a front surface configured to a support the one or more accelerometers and one or more gyroscopes and a back surface opposite the front surface, and wherein the wrapping comprises wrapping the flexible inertial sensor around the plurality of external surfaces of support structure with the front surface facing the support structure and the back surface facing away from the support structure.

17. The method of claim 14, wherein the support structure comprises a plurality of grooves and each of the one or more accelerometers and the one or more gyroscopes is received within a respective groove of the plurality of grooves when the flexible inertial sensor is wrapped around the plurality of external surfaces of the support structure.

18. The method of claim 14, further comprising positioning the sensing module within a housing.

19. The method of claim 18, further comprising arranging one or more damping units between the sensing module and the housing.

20. The method of claim 19, further comprising mounting the housing onto an unmanned aerial vehicle.

21. The method of claim 19, wherein the flexible inertial sensor comprises a flexible circuit board, and wherein the one or more accelerometers and the one or more gyroscopes are each coupled to the flexible circuit board.

22. The method of claim 21, wherein the flexible circuit board comprises a plurality of panels, and wherein the wrapping comprises folding the flexible circuit board such that at least a subset of the plurality of panels are orthogonal to each other.

23. The method of claim 22, wherein the one or more accelerometers and the one or more gyroscopes are positioned on the plurality of panels such that at least a subset of the one or more accelerometers and the one or more gyroscopes are orthogonal to each other when the flexible circuit board is folded.

24. The method of claim 22, wherein the flexible circuit board comprises six panels and the support structure is a cube-shaped structure comprising six external faces, and wherein each of the six panels substantially covers a corresponding external face of the support structure when the flexible circuit board is folded.

25. The method of claim 24, wherein the one or more damping units comprise six damping units, and wherein the arranging comprises positioning each of the six damping units to be in contact with a corresponding panel of the flexible circuit board.

26. The method of claim 19, wherein the one or more damping units are arranged relative to the sensing module such that an elastic center of the one or more damping units substantially coincides with a centroid of the sensing module.

41. The device of claim 3, wherein all of the one or more accelerometers and one or more gyroscopes supported by the flexible inertial sensor are coupled to the front surface.

42. The device of claim 4, wherein the one or more accelerometers and one or more gyroscopes are directed inwards, facing one another, while received within the plurality of grooves of the support structure.

43. The device of claim 1, wherein the plurality of external surfaces of the support structure comprises a first external surface and a second external surface adjacent the first external surface, and wherein the flexible inertial sensor comprises a single member that extends continuously over both the first external surface and the second external surface.

44. An inertial measurement system comprising:

the device of claim 1;

a housing configured to receive the sensing module therein; and

one or more damping units disposed in a space between the sensing module and the housing;

wherein the flexible inertial sensor is configured to wrap around the plurality of external surfaces of the support structure, such that the flexible inertial sensor is positioned between the support structure and the one or more damping units.

27. A movable device, the device comprising:

a sensing module comprising a support structure and a flexible inertial sensor, wherein the support structure comprises a plurality of external surfaces facing away from one another, and wherein the flexible inertial sensor is configured to wrap around the plurality of external surfaces of the support structure, such that the flexible inertial sensor substantially covers the plurality of external surfaces of the support structure, and wherein the flexible inertial sensor comprises one or more accelerometers and one or more gyroscopes; and

a carrier carrying the sensing module, wherein the flexible inertial sensor is configured to generate a signal indicative of at least one of an acceleration or a rotation of the carrier.

28. The device of claim 27, wherein the carrier is an unmanned aerial vehicle.

29. The device of claim 27, wherein the carrier is an aircraft, a watercraft, a car, or a robot.

30. The device of claim 27, further comprising a control computer operably coupled to the flexible inertial sensor and configured to receive and process the signal in order to determine at least one of the acceleration or the rotation of the carrier.

31. The device of claim 27, wherein the flexible inertial sensor comprises a front surface configured to a support the one or more accelerometers and one or more gyroscopes and a back surface opposite the front surface, and wherein the flexible inertial sensor wraps around the plurality of external surfaces of the support structure with the front surface facing the support structure and the back surface facing away from the support structure.

32. The device of claim 27, wherein the support structure comprises a plurality of grooves and each of the one or more accelerometers and the one or more gyroscopes is received within a respective groove of the plurality of grooves when the flexible inertial sensor is wrapped around the plurality of external surfaces of the support structure.

33. The device of claim 27, further comprising a housing containing therein said sensing module.

34. The device of claim 33, further comprising one or more damping units arranged between the sensing module and the housing.

35. The device of claim 34, wherein the flexible inertial sensor comprises a flexible circuit board, and wherein the one or more accelerometers and the one or more gyroscopes are each coupled to the flexible circuit board.

36. The device of claim 35, wherein the flexible circuit board comprises a plurality of panels, the flexible circuit board being foldable such that at least a subset of the plurality of panels are orthogonal to each other when the flexible circuit board is wrapped around the at least a portion of the support structure.

37. The device of claim 36, wherein the one or more accelerometers and the one or more gyroscopes are positioned on the plurality of panels such that at least a subset of the one or more accelerometers and the one or more gyroscopes are orthogonal to each other when the flexible circuit board is folded.

38. The device of claim 36, wherein the flexible circuit board comprises six panels and the support structure is a cube-shaped structure comprising six external faces, and wherein each of the six panels substantially covers a corresponding external face of the support structure when the flexible circuit board is folded.

39. The device of claim 38, wherein the one or more damping units comprise six damping units, each of the six damping units being in contact with a corresponding panel of the flexible circuit board.

40. The device of claim 34, wherein the one or more damping units are arranged relative to the sensing module such that an elastic center of the one or more damping units substantially coincides with a centroid of the sensing module.