Inertial sensing device

• US 10,184,795 B2
• Filed: 05/25/2017
• Issued: 01/22/2019
• Est. Priority Date: 04/25/2014
• 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: Song, Jian Yu, Shi, Ren Li, Wang, Tao
• Primary Examiner(s): Laballe, Clayton E
• Assistant Examiner(s): Butler, Kevin
• Application Number:
  US15/605,903
• Publication Number:
  US 20170261323A1
• Time in Patent Office: 607 Days
• Field of Search: 73493
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64U 2101/30 for imaging, photography or videography
• CPC Class Codes: G01C 19/00 Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
• CPC Class Codes: G01C 19/04 Details
• 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: G01P 1/02 Housings
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 15/08 with conversion into electric or magnetic values
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

Improved sensing devices are provided for determining the spatial disposition of a movable object. In one aspect, an apparatus for determining a spatial disposition of a movable object comprises: a support base configured to be carried by a movable object; one or more accelerometers coupled to the support base via a first damping element configured to damp motion of the one or more accelerometers; and one or more gyroscopes coupled to the support base via a second damping element configured to damp motion of the one or more gyroscopes, wherein an amount of motion damping provided by the first damping element is greater than an amount of motion damping provided by the second damping element.

Claims

1. A system for determining a spatial disposition of a movable object, the system comprising:

a support base configured to be carried by the movable object, wherein the movable object is an unmanned aerial vehicle (UAV);

a plurality of damping elements coupled to the support base; and

a plurality of inertial measurement units coupled to the support base via the plurality of damping elements,

wherein each of the plurality of inertial measurement units are coupled to the support base via at least one of the plurality of damping elements to provide a corresponding damping motion for each of the plurality of inertial measurement units,

wherein a first corresponding damping motion provided for a first inertial measurement unit of the plurality of inertial measurement units is different from a second corresponding damping motion provided for a second inertial measurement unit of the plurality of inertial measurement units, and

wherein a stiffness of a first damping element of the plurality of damping elements is less than that of a second damping element of the plurality of damping elements.

2. The system of claim 1, wherein the first inertial measurement unit comprises a first accelerometer coupled to the support base via the first damping element of the plurality of damping elements configured to provide the first damping motion;

and wherein the second inertial measurement unit of the plurality of inertial measurement units comprises a first gyroscope coupled to the support base via the second damping element of the plurality of damping elements configured to provide the second damping motion.

3. The system of claim 2, wherein the first accelerometer is configured to measure acceleration around a first rotational axis.

4. The system of claim 2, wherein the first accelerometer is a microelectromechanical system (MEMS) sensor, and wherein the first gyroscope is a MEMS sensor.

5. The system of claim 4, wherein the first accelerometer and the first gyroscope are integrated onto a single chip.

6. The system of claim 2, wherein the plurality of inertial measurement units further comprises a second accelerometer and a third accelerometer, wherein the first accelerometer, second accelerometer, and third accelerometer are positioned substantially orthogonally relative to one another.

7. The system of claim 6, wherein the first accelerometer, second accelerometer, and third accelerometer are configured to measure acceleration relative to a roll axis, a pitch axis, and a yaw axis of the movable object, respectively.

8. The system of claim 6, wherein the plurality of inertial measurement units further comprises a fourth accelerometer, the fourth accelerometer being configured to provide redundant measurements as the first accelerometer, the second accelerometer, or the third accelerometer.

9. The system of claim 2, wherein the plurality of inertial measurement units further comprises a second gyroscope and a third gyroscope, wherein the first gyroscope, second gyroscope, and third gyroscope are positioned substantially orthogonally relative to one another.

10. The system of claim 9, wherein the first gyroscope, second gyroscope and third gyroscope are configured to measure orientation relative to a roll axis, a pitch axis, and a yaw axis of the movable object, respectively.

11. The system of claim 9, wherein the plurality of inertial measurement units further comprises a fourth gyroscope, the fourth gyroscope being configured to provide redundant measurements as the first gyroscope, the second gyroscope, or the third gyroscope.

12. The system of claim 1, wherein at least one of the plurality of inertial measurement units is coupled to the base support via at least two of the plurality of damping elements.

13. The system of claim 1, wherein at least two of the plurality of inertial measurement units share a damping element.

14. The system of claim 1, wherein the plurality of damping elements comprises at least one of a sponge, a foam, or a rubber material.

15. The system of claim 1, wherein the amount of the first damping motion improves the performance of the first inertial measurement unit, and the amount of the second damping motion improves the performance of the second inertial measurement unit.

16. A method of determining a spatial disposition of a movable object, the method comprising:

coupling a plurality of inertial measurement units to a support base via a plurality of damping elements, the support base being configured to be carried by the movable object, wherein the movable object is an unmanned aerial vehicle (UAV); and

providing a corresponding damping motion for each of the plurality of inertial measurement units via at least one of the plurality of damping elements, wherein a first corresponding damping motion provided for a first inertial measurement unit of the plurality of inertial measurement units is different from a second corresponding damping motion provided for a second inertial measurement unit of the plurality of inertial measurement units, and wherein a stiffness of a first damping element of the plurality of damping elements is less than that of a second damping element of the plurality of damping elements.

17. The method of claim 16, wherein providing the first inertial measurement unit of the plurality of inertial measurement units comprises providing a first accelerometer and a first gyroscope.

18. The method of claim 17, wherein providing the first accelerometer and the first gyroscope comprises providing microelectromechanical system (MEMS) sensors integrated onto a single chip.

19. The method of claim 16, wherein providing the corresponding damping motion comprises providing at least one inertial measurement unit coupled to the base support via at least two of the plurality of damping elements.