Hover control

Patent metadata

Field	Value
Publication number	US-11073389-B2
Application number	US-202016996822-A
Country	US
Kind code	B2
Filing date	Aug 18, 2020
Priority date	Mar 28, 2016
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

An unmanned aerial vehicle (UAV) includes a power device communicatively configured to provide power for the UAV and one or more processors coupled to the power device. The one or more processors are configured to obtain a flight velocity of the UAV corresponding to the power, obtain an image frame as a keyframe in response to that the flight velocity satisfies a preset condition, and control the UAV to hover using the keyframe as a reference object.

First claim

What is claimed is:

1. An unmanned aerial vehicle (UAV) comprising:
a power device communicatively configured to provide power for the UAV; and
one or more processors coupled to the power device and configured to:
obtain a flight velocity of the UAV corresponding to the power;
obtain an image frame as a keyframe in response to that the flight velocity satisfies a preset condition; and
control the UAV to hover using the keyframe as a reference object.

2. The UAV of claim 1 , wherein the one or more processors are further configured to:
obtain an image frame after the keyframe as a correction frame; and
correct a displacement of the UAV according to the correction frame and the keyframe to control the UAV to hover.

3. The UAV of claim 2 , wherein the one or more processors are further configured to:
obtain, according to the correction frame and the keyframe, a flight displacement vector of the UAV between a time corresponding to the correction frame and a time corresponding to the keyframe; and
control, according to the flight displacement vector, the displacement of the UAV to cause the flight displacement vector to be less than or equal to a preset value.

4. The UAV of claim 3 , wherein the flight displacement vector includes at least one of a rotational motion parameter or a translational motion parameter of the UAV between the time corresponding to the correction frame and the time corresponding to the keyframe.

5. The UAV of claim 2 , wherein the one or more processors are further configured to:
select a stationary feature from the keyframe; and
correct the displacement of the UAV according to the stationary feature.

6. The UAV of claim 5 , wherein the one or more processors are further configured to correct the displacement of the UAV by coinciding, with respect to the stationary feature, feature information of the keyframe and feature information of the correction frame in a same coordinate system.

7. The UAV of claim 2 , wherein:
the correction frame is a first correction frame; and
the one or more processors are configured to:
obtain an image frame after the first correction frame as a second correction frame; and
continue to correct the displacement of the UAV according to the second correction frame and the keyframe.

8. The UAV of claim 1 , wherein the preset condition includes the flight velocity being zero.

9. The UAV of claim 1 , wherein:
the flight velocity is a first flight velocity, the preset condition is a first preset condition, and the image frame is a first image frame; and
the one or more processors are further configured to:
obtain a second flight velocity after a preset interval of time from a time of obtaining the first image frame; and
in response to the second flight velocity satisfying a second preset condition, obtain a second image frame after the preset interval of time from the time of obtaining the first image frame and update the keyframe to be the second image frame.

10. The UAV of claim 1 , wherein:
the image frame is a first image frame and the preset condition is a first preset condition; and
the one or more processors are configured to:
obtain a second image frame after a preset interval of time from a time of obtaining the first image frame; and
in response to a similarity between the first image frame and the second image frame satisfying a second preset condition, update the keyframe to be the second image frame.

11. The UAV of claim 10 , wherein the one or more processors are further configured to:
select a stationary feature from the second image frame; and
determine the similarity according to the stationary feature.

12. The UAV of claim 10 , wherein the one or more processors are further configured to, in response to the similarity between the first image frame and the second image frame satisfying a third preset condition, maintain the keyframe to be the first image frame.

13. The UAV of claim 1 , wherein the preset condition includes an integral of the flight velocity being less than a preset threshold.

14. The UAV of claim 1 , further comprising:
an image sensor communicatively coupled to the one or more processors and configured to capture the image frame.

15. The UAV of claim 14 , wherein the image sensor includes one or more cameras.

16. The UAV of claim 1 , further comprising:
a velocity sensor communicatively coupled to the one or more processors and configured to detect the flight velocity of the UAV.

17. The UAV of claim 16 , wherein the velocity sensor includes at least one of an Inertial Measurement Unit (IMU), an accelerometer, or a distance measurement sensor.

18. The UAV of claim 1 , wherein the one or more processors are further configured to obtain displacement information and time information with respect to a flight of the UAV from a Global Positioning System (GPS) to obtain the flight velocity of the UAV.

19. The UAV of claim 1 , where the power device includes one or more drive motors and an electronic governor.

20. The UAV of claim 1 , wherein the one or more processors are further configured to obtain the flight velocity of the UAV through another processor.

Assignees

• Sz Dji Technology Co Ltd

Inventors

• Liu Ang
• Zhao Yongjian
• Zhou Guyue

Classifications

• B64U2201/00

  UAVs characterised by their flight controls · CPC title

• B64U2101/30

  for imaging, photography or videography · CPC title

• G05D1/042 Primary

  specially adapted for aircraft · CPC title

• G05D1/0038

  by providing the operator with simple or augmented images from one or more cameras located onboard the vehicle, e.g. tele-operation (images analyzed by a computer and used for automatic navigation G05D1/0246) · CPC title

• G05D1/0607

  specially adapted for aircraft · CPC title