System of drones provided with recognition beacons

• US 8,818,083 B2
• Filed: 11/19/2009
• Issued: 08/26/2014
• Est. Priority Date: 12/04/2008
• Status: Expired due to Fees

• Current Assignee: Parrot Drones
• Original Assignee: Parrot SA
• Inventors: Jonchery, Claire, Derbanne, Thomas, Lefebure, Martin
• Primary Examiner(s): STREGE, JOHN B
• Application Number:
  US13/132,149
• Publication Number:
  US 20110299732A1
• Time in Patent Office: 1,741 Days
• Field of Search: 382/103, 382/162, 382/165, 382/287
• US Class Current: 382/162
• CPC Class Codes: A63F 2300/1093 using visible light
• CPC Class Codes: A63H 27/12 Helicopters A63H27/04 takes precedence; Flying tops
• CPC Class Codes: A63H 30/04 using wireless transmission
• CPC Class Codes: G06V 10/143 Sensing or illuminating at different wavelengths
• CPC Class Codes: G06V 10/245 by locating a pattern; Special marks for positioning

Abstract

The present invention relates to a system (1) of remotely controlled drones (10, 12) fitted with respective cameras (14) enabling a virtual shot from an assailant drone (12) at a target drone (10) to be validated by recognizing the target drone (10) in a video image (17) supplied by the camera (14) of the assailant drone (12) while firing a virtual shot. The recognition means comprise a beacon (15, 16) arranged on the target drone (10) and covered in two first strips (18) of a first color reflecting light at a first wavelength lying in the range 590 nm to 745 nm, situated on either side of at least one second strip (19, 20) of a second color reflecting light at a second wavelength, lying in a range 445 nm to 565 nm. It is thus possible to identify very reliably drones flying in an open space whether outdoors or indoors, in spite of the very great variety of interfering details present in the background images that are likely to be picked up by the camera.

Claims

1. A system (1) of remotely controlled drones (10, 12) fitted with respective cameras (14) enabling a virtual shot from an assailant drone (12) at a target drone (10) to be validated by recognizing the target drone (10) in a video image (17) supplied by the camera (14) of the assailant drone (12) while firing a virtual shot,

the system being characterized in that the recognition means comprise a beacon (15, 16) arranged on the target drone (10) and covered in two first strips (18) of a first color reflecting light at a first wavelength, situated on either side of at least one second strip (19, 20) of a second color reflecting light at a second wavelength, different from the first;

in that the emission spectrum of the first color of the two first strips (18) lies in the range 590 nm to 745 nm, while the emission spectrum of at least one second strip (19, 20) lies in the range 445 nm to 565 nm, and

the assailant drone comprising means for analyzing the image taken while firing a virtual shot that comprises the following means;

means for detecting a first pixel of the first color in the image;

means for detecting a first group of pixels of said first color including the previously-detected pixel;

means for detecting a group of pixels of the second color in the vicinity of the first group of pixels of the first color;

means for recognizing a second group of pixels of the first color; and

means for verifying recognition and consistency conditions amongst the detected groups of pixels.

2. A system according to claim 1, characterized in that the beacon (15, 16) is cylindrical in shape.

3. A system according to claim 2, characterized in that the axis (3) of the cylindrical beacon (15, 16) is perpendicular to a main plane (5) of the target drone.

4. A system according to claim 3, characterized in that the first strips (18) and at least one of the second strips (19, 20) extend circumferentially over the surface of the beacon (15, 16) in mutually coplanar planes that are perpendicular to the axis (3) of the cylinder.

5. A system according to claim 1, characterized in that the first color of the two first strips (18) is fluorescent.

6. A system according to claim 1, characterized in that the beacon (16) presents at least two second strips (19, 20).

7. A system according to claim 1, characterized in that the means for verifying the recognition and consistency conditions of the groups of pixels include at least:

means for verifying horizontal connectivity of the groups of pixels; and

means for verifying vertical semi-connectivity of the groups of pixels, such that a row of pixels belonging to no group is acceptable between the different groups.

8. A system according to claim 1, characterized in that the means for verifying the recognition and consistency conditions of the groups of pixels include at least:

means for analyzing luminance variation for each group of pixels;

means for analyzing the chrominance difference between the two first strips of the first color and the at least one second strip of the second color in a V image coding channel (red);

means for analyzing the chrominance difference between the two first strips of the first color in a U image coding channel (blue); and

means for analyzing the minimum chrominance of the two first strips and of the second strip(s).

10. A system according to claim 7, characterized in that the means for verifying the recognition and consistency conditions of the groups of pixels include at least:

means for analyzing luminance variation for each group of pixels;

means for analyzing the chrominance difference between the two first strips of the first color and the at least one second strip of the second color in a V image coding channel (red);

means for analyzing the chrominance difference between the two first strips of the first color in a U image coding channel (blue); and

means for analyzing the minimum chrominance of the two first strips and of the second strip(s).

11. A system according to claim 4, characterized in that the first color of the two first strips (18) is fluorescent.

12. A system according to claim 4, characterized in that the beacon (16) presents at least two second strips (19, 20).

13. A system according to claim 5, characterized in that the beacon (16) presents at least two second strips (19, 20).

9. A drone (10, 12) provided with a camera (14) enabling a virtual shot at a target drone (10) to be validated by recognizing the target drone (10) in a video image (17) supplied by its camera (14) while firing the virtual shot, the drone being characterized in that it includes recognition means enabling it to be used (12) in a system as a target drone (10) and as an assailant drone (12),

the system being characterized in that the recognition means comprise a beacon (15, 16) arranged on the target drone (10) and covered in two first strips (18) of a first color reflecting light at a first wavelength, situated on either side of at least one second strip (19, 20) of a second color reflecting light at a second wavelength, different from the first;

in that the emission spectrum of the first color of the two first strips (18) lies in the range 590 nm to 745 nm, while the emission spectrum of at least one second strip (19, 20) lies in the range 445 nm to 565 nm, and

the assailant drone comprising means for analyzing the image taken while firing a virtual shot that comprises the following means;

means for detecting a first pixel of the first color in the image;

means for detecting a first group of pixels of said first color including the previously-detected pixel;

means for detecting a group of pixels of the second color in the vicinity of the first group of pixels of the first color;

means for recognizing a second group of pixels of the first color; and

means for verifying recognition and consistency conditions amongst the detected groups of pixels.