Inertia measurement module for unmanned aircraft

Patent metadata

Field	Value
Publication number	US-9772343-B2
Application number	US-201114241891-A
Country	US
Kind code	B2
Filing date	Sep 15, 2011
Priority date	Sep 2, 2011
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

The present disclosure relates to an inertia measurement module for an unmanned aircraft, which comprises a housing assembly, a sensing assembly and a vibration damper. The vibration damper comprises a first vibration-attenuation cushion; and the sensing assembly comprises a first circuit board, a second circuit board and a flexible signal line for connecting the first circuit board and the second circuit board. An inertia sensor is fixed on the second circuit board, and the first circuit board is fixed on the housing assembly. The inertia measurement module further comprises a weight block, and the second circuit board, the weight block, the first vibration-attenuation cushion and the first circuit board are bonded together. The present disclosure greatly reduces the influence of the operational vibration frequency of the unmanned aircraft on the inertia sensor and improves the measurement stability of the inertia sensor.

First claim

What is claimed is:

1. An inertia measurement module for an unmanned aircraft, comprising:
a sensing assembly comprising:
a first circuit board;
a second circuit board comprising at least one inertia sensor; and
a flexible signal line that connects the first circuit board to the second circuit board;

a weight block comprising a first surface and a second surface opposite the first surface, wherein a recess is (1) formed only on the second surface, and (2) configured to support the second circuit board that is embedded in the recess;
a first vibration-attenuation cushion and a second vibration-attenuation cushion arranged on opposite sides of the weight block, wherein the first vibration-attenuation cushion is provided as a sheet extending between the first surface of the weight block and the first circuit board, and wherein the second vibration-attenuation cushion abuts against the second circuit board via an adhesive layer; and
a housing assembly comprising a chamber configured to support the sensing assembly, the weight block, and the first vibration-attenuation cushion and second vibration-attenuation cushion therein.

2. The inertia measurement module of claim 1 , wherein the second vibration-attenuation cushion is separated from the second circuit board via the adhesive layer.

3. The inertia measurement module of claim 1 , wherein the adhesive layer is attached onto the second circuit board.

4. The inertia measurement module of claim 1 , wherein the first and second vibration-attenuation cushions are arranged on the opposite sides of the weight block along a vertical axis extending longitudinally through the weight block.

5. The inertia measurement module of claim 1 , wherein the first circuit board is rigidly affixed to an inner portion of the housing assembly, a first side of the second vibration-attenuation cushion abuts against the second circuit board, and a second side of the second vibration-attenuation cushion abuts against another inner portion of the housing assembly.

6. The inertia measurement module of claim 1 , wherein the first circuit board is arranged outside of the recess of the weight block.

7. The inertia measurement module of claim 1 , wherein the recess is dimensioned to match a shape of the second circuit board, and wherein a distance between the first surface and the first circuit board is less than a distance between the second surface and the first circuit board.

8. The inertia measurement module of claim 1 , wherein at least one of the first and second vibration-attenuation cushions is made of a buffering material having a predefined elasticity.

9. The inertia measurement module of claim 1 , wherein the weight block is made of a metallic material.

10. The inertia measurement module of claim 1 , wherein the weight block is dimensioned to take a shape of a cuboid.

11. The inertia measurement module of claim 1 , wherein the second circuit board is disposed on a supporting sheet that is bonded to the weight block.

12. The inertia measurement module of claim 1 , wherein at least one of the first and second vibration-attenuation cushions is made of an elastic material comprising a plurality of cavities.

13. The inertia measurement module of claim 1 , wherein the first vibration-attenuation cushion and the second vibration-attenuation cushion are adapted to absorb vibrations on opposite sides of the second circuit board.

14. The inertia measurement module of claim 1 , wherein the second circuit board is a flexible circuit board.

15. The inertia measurement module of claim 1 , wherein the inertia sensor comprises at least one of the following: a gyroscope for obtaining an angular speed signal of the unmanned aircraft, and an accelerometer for obtaining an acceleration signal of the unmanned aircraft.

16. The inertia measurement module of claim 15 , wherein the angular speed signal and the acceleration signal are transmitted from the second circuit board to the first circuit board via the flexible signal line.

17. The inertia measurement module of claim 1 , wherein the second circuit board further comprises a power source.

18. The inertia measurement module of claim 1 , wherein a size of the second circuit board is smaller than a size of the first circuit board.

19. The inertia measurement module of claim 1 , wherein the sensing assembly further comprises a signal input interface terminal and a signal output interface terminal respectively operably coupled to opposing sides of the first circuit board.

20. The inertia measurement module of claim 1 , wherein a shape of the first vibration-attenuation cushion is substantially the same as a shape of the second vibration-attenuation cushion.

21. The inertia measurement module of claim 1 , wherein the first vibration-attenuation cushion is configured to absorb vibrations on a first side of the second circuit board, and wherein the second vibration-attenuation cushion is configured to absorb vibrations on a second side of the second circuit board that is opposite to the first side of the second circuit board.

22. The inertia measurement module of claim 1 , wherein a contact area between the second vibration-attenuation cushion and the second circuit board ranges from about 12.6 mm 2 to 50.2 mm 2 .

23. The inertia measurement module of claim 1 , wherein a contact area between the second vibration-attenuation cushion and the second circuit board is about 28 mm 2 .

24. The inertia measurement module of claim 1 , wherein at least one of the first and second vibration-attenuation cushions has a length of about 13 mm to 20 mm, a width of about 13 mm to 20 mm, and a thickness of about 3 mm to 4 mm.

25. The inertia measurement module of claim 1 , wherein the weight block has a weight of about 1 g to 30 g.

26. The inertia measurement module of claim 19 , wherein the opposing sides of the first circuit board are different from a surface of the first circuit board that is rigidly affixed to an inner portion of the housing assembly.

27. The inertia measurement module of claim 1 , wherein the sensing assembly, the weight block, and the first and second vibration-attenuation cushions are rigidly supported within and by the housing assembly.

28. An inertia measurement module for an unmanned aircraft, comprising:
a sensing assembly comprising:
a first circuit board;
a second circuit board comprising at least one inertia sensor; and
a flexible signal line that connects the first circuit board to the second circuit board;

a weight block comprising a first surface and a second surface opposite the first surface, wherein a recess is (1) formed only on the second surface, and (2) configured to support the second circuit board such that the second circuit board is embedded in said recess;
a first vibration-attenuation cushion and a second vibration-attenuation cushion arranged on opposite sides of the weight block, wherein the first vibration-attenuation cushion is provided as a sheet extending between the first surface of the weight block and the first circuit board, and wherein the second vibration-attenuation cushion abuts against the second circuit board via an intermediate layer; and
a housing assembly comprising a chamber configured to support the sensing assembly, the weight block, and the first vibration-attenuation cushion and the second vibration-attenuation cushion therein.

Assignees

• Wang Tao
• Zhao Tao
• Sz Dji Technology Co Ltd

Inventors

• Wang Tao
• Zhao Tao

Classifications

• G01C19/5663

  Manufacturing; Trimming; Mounting; Housings · CPC title

• G01C19/56

  Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces · CPC title

• G01P1/003 Primary

  used for damping · CPC title

• G01P1/023

  for acceleration measuring devices · CPC title

• G01P15/0802

  Details · CPC title