PROCEDURE FOR THE DETECTION AND DISPLAY OF ARTIFICIAL OBSTACLES FOR A ROTARY-WING AIRCRAFT

• US 20150279219A1
• Filed: 03/30/2015
• Published: 10/01/2015
• Est. Priority Date: 03/28/2014
• Status: Active Grant

• Current Assignee: Airbus Helicopters
• Original Assignee: Airbus Helicopters
• Inventors: GILLET, Marianne, FILIAS, Francois-Xavier, PIRE, Richard
• Granted Patent: US 9,401,093 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 13/93 for anti-collision purposes
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 17/933 of aircraft or spacecraft
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/30261 Obstacle
• CPC Class Codes: G06V 20/17 taken from planes or by drones
• CPC Class Codes: G06V 20/58 Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads
• CPC Class Codes: G08G 5/0021 located in the aircraft
• CPC Class Codes: G08G 5/04 Anti-collision systems

Abstract

A procedure for the detection and display of the ground and of obstacles through the use of detection means installed onboard a vehicle, which detection means send measurement signals toward the ground and receive a plurality of elementary plots (Pe). The procedure makes it possible to create a grid of the ground along a horizontal plane, with each ground cell (Ms(i,j)) consisting of an elementary plot (Pe) having a minimum altitude Zmin(i,j)), and with each other elementary plot (Pe) corresponding to the ground cell (Ms(i,j)) and having a different altitude (Z_n(i,j)), thereby forming an obstacle plot (Po_n(i,j)). Each newly received elementary plot (Pe) is then compared against the corresponding ground cell (Ms(i,j)) and processed according to its altitude (Z_n(i,j)). The ground cells (Ms(i,j)) and/or the obstacle plots (Po_n(i,j)) are displayed on display means in order to indicate to the pilot of the vehicle the potential obstacles other than the ground.

Claims

1. A procedure for the detection and display of the ground and of obstacles through the use of detection means intended to be installed on board a vehicle, which detection means send measurement signals and receive a plurality of elementary plots (Pe) expressed in the form of three-dimensional coordinates, with the elementary plots (Pe) representing at least part of the environment of the vehicle, which procedure includes:

a first stage consisting of the creation of a two-dimensional grid of the ground along a horizontal plane, using ground cells (Ms(i,j)), with each ground cell (Ms(i,j)) consisting of an elementary plot (Pe) having an altitude (Z_Pe), with the elementary plot (Pe) consisting of the elementary plot (Pe) corresponding to the ground cell (Ms(i,j)) whose altitude (Z_Pe) is a minimum altitude (Zmin(i,j));

a second stage consisting of the creation of a network of obstacle plots (Po_n(i,j)), with each elementary plot (Pe) corresponding to a ground cell (Ms(i,j)) and having an altitude (Z_Pe) greater than the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)) forming an obstacle plot (Po_n(i,j));

a third stage consisting of the storage in memory of the ground cells (Ms(i,j)), with each ground cell (Ms(i,j)) being stored in memory with the minimum altitude (Zmin(i,j));

a fourth stage consisting of the storage in memory of the obstacle plots (Po_n(i,j)), with each obstacle plot (Po_n(i,j)) being stored in memory with an altitude (Z_n(i,j)) equal to the altitude (Z_Pe);

a fifth stage consisting of a comparison of each ground cell (Ms(i,j)) against each newly received elementary plot (Pe) having an altitude (Z_Pe) and corresponding to the ground cell (Ms(i,j)), such that;

if any minimum altitude (Zmin(i,j)) is not stored in memory for the ground cell (Ms(i,j)), then the altitude (Z_Pe) of the newly received elementary plot (Pe) is stored in memory for the ground cell (Ms(i,j)) as the minimum altitude (Zmin(i,j));

if the altitude (Z_Pe) of the newly received elementary plot (Pe) is greater than the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)), then the newly received elementary plot (Pe) is stored in memory as an obstacle plot (Po_n(i,j)) having an altitude (Z_n(i,j)) that is equal to the altitude (Z_Pe) of the newly received elementary plot (Pe), with the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)) remaining unchanged;

if the altitude (Z_Pe) of the newly received elementary plot (Pe) is less than the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)), then an obstacle plot (Po_n(i,j)) is stored in memory with an altitude (Z_n(i,j)) that is equal to the minimum altitude (Zmin(i,j)), and the altitude (Z_Pe) of the newly received elementary plot (Pe) is stored in memory as the new minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j));

if the altitude (Z_Pe) of the newly received elementary plot (Pe) is equal to the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)), then the newly received elementary plot (Pe) is ignored, and

a sixth stage consisting of the display of the obstacle plots (Po_n(i,j)).

2. The procedure according to claim 1, wherein each obstacle plot (Po_n(i,j)) having a difference in altitude between the altitude (Z_n(i,j)) and the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)) corresponding to the obstacle plot (Po_n(i,j)) that is less than a first threshold is ignored during the sixth stage consisting of the display.

3. The procedure according to claim 1, wherein each obstacle plot (Po_n(i,j)) having a difference in altitude between the altitude (Z_n(i,j)) and the minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)) corresponding to the obstacle plot (Po_n(i,j)) that is greater than a second threshold is ignored during the sixth stage consisting of the display.

4. The procedure according to claim 1, wherein each ground cell (Ms(i,j)) is in the form of a square whose dimensions vary depending on the position of the vehicle with respect to the ground.

5. The procedure according to claim 1, wherein each ground cell (Ms(i,j)) is in the form of a square, each of whose sides corresponds to 10 meters on the ground.

6. The procedure according to claim 2, wherein the first threshold is equal to 30 feet.

7. The procedure according to claim 3, wherein the second threshold is equal to 500 feet.

8. The procedure according to claim 1, wherein during the course of the sixth stage consisting of the display, each ground cell (Ms(i,j)) is displayed taking into consideration the minimum altitude (Zmin(i,j)) associated with the ground cell (Ms(i,j)), thereby forming a three-dimensional grid representing the ground.

9. The procedure according to claim 1, wherein a preliminary stage consisting of the conversion of the three-dimensional coordinates of the elementary plots (Pe) is performed prior to the first stage, in order to convert the three-dimensional coordinates of the elementary plots (Pe) of a reference mark linked to the vehicle into a ground-based geographic reference mark.

10. The procedure according to claim 1, wherein each ground cell (Ms(i,j)) forms a digital terrain model (MNT), and the initial minimum altitude (Zmin(i,j)) of the ground cell (Ms(i,j)) is the altitude of the digital terrain model (MNT).

11. A program containing code stored on a medium or embodied in a signal, which code can be read or executed by a data-processing unit intended to be installed on board a vehicle in order to process a plurality of elementary plots (Pe) received by detection means, wherein the code includes code segments for the implementation of the stages of the procedure according to claim 1.

12. A device for the detection and display of the ground and of obstacles, which device, intended to be installed on board a vehicle, includes detection means that receive a plurality of elementary plots (Pe);

a reference and course heading system; and

a location system, as well as a processing unit;

one or more memory storage means; and

display means, wherein the device for the detection and display of the ground and of obstacles implements the procedure according to claim 1.