Ground-based camera surveying and guiding method for aircraft landing and unmanned aerial vehicle recovery

• US 9,057,609 B2
• Filed: 03/27/2009
• Issued: 06/16/2015
• Est. Priority Date: 03/27/2009
• Status: Active Grant

• Current Assignee: National University of Defense Technology
• Original Assignee: National University of Defense Technology
• Inventors: Yu, Qifeng, Lei, Zhihui, Zhang, Xiaohu, Shang, Yang, Zhang, Heng, Zhou, Xiang
• Primary Examiner(s): Perungavoor, Sath V
• Assistant Examiner(s): PARIKH, DAKSHESH D
• Application Number:
  US13/260,471
• Publication Number:
  US 20120075461A1
• Time in Patent Office: 2,272 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B64U 70/60 Take-off or landing of UAVs from a runway using their own power
• CPC Class Codes: G01C 11/00 Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
• CPC Class Codes: G01C 21/10 by using measurements of speed or acceleration G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G05D 1/0676 specially adapted for landing
• CPC Class Codes: G08G 5/0026 located on the ground
• CPC Class Codes: G08G 5/025 Navigation or guidance aids radar or analogous systems specially adapted for landing purposes G01S13/913

Abstract

A ground-based videometrics guiding method for aircraft landing or unmanned aerial vehicles recovery is provided. The method comprised the following steps: setting videos(1,2,3,4,5,6) near the landing area of the aircraft or unmanned aerial vehicles; real-time imaging the aircraft or unmanned aerial vehicles during their final approaches; and real-time measuring the trajectory, velocity, acceleration, post and other motion parameters of the aircraft or unmanned aerial vehicles by analyzing the video images and using videometrics technology, so as to provide guiding information for the aircraft landing or unmanned aerial vehicles recovery.

Claims

1. A ground-based camera surveying and guiding method for aircraft landing and unmanned aerial vehicle recovery, comprising:

(1) arranging video cameras near landing areas of an aircraft or an unmanned aerial vehicle, the fields of view of the video cameras covering a survey area where the aircraft or the unmanned aerial vehicle approaches;

(2) calibrating the video cameras;

(3) when surveying is initiated, starting to acquire images of the survey area and detect the aircraft or the unmanned aerial vehicle in real time; and

(4) when the aircraft or the unmanned aerial vehicle is detected to have entered the survey area, starting to identify and extract features of the aircraft or the unmanned aerial vehicle and compute a three-dimensional position and an altitude of the aircraft or the unmanned aerial vehicle, and providing guidance for aircraft landing or unmanned aerial vehicle recovery by computing a track, velocity and acceleration of the aircraft or the unmanned aerial vehicle through data filtering,

wherein the video camera are arranged near the landing areas of the aircraft or the unmanned aerial vehicle in one of the following manners;

a. fixing and installing fixed-focus video cameras at both sides of the landing areas, an intersected field of view of the video cameras at both sides of the landing areas covering an area where the aircraft approaches according to the guiding requests, and, where the landing areas are narrow and long, fixing and installing multiple sets of fixed-focus video cameras, each set of the fixed-focus video cameras comprising at least two fixed-focus video cameras, and fields of view of the video cameras at both sides of the landing areas respectively overlapping to cover the survey area from a far end to a near end;

b. installing tripod heads respectively at both sides of the landing areas, each tripod head having a zooming video camera installed thereon, and according to guiding requests, during an approaching process of the aircraft or the unmanned aerial vehicle, scanning and covering the survey area through an overlapping field of view of the two video cameras as the aircraft moves by controlling rotation of the tripod heads and zooming of the video cameras;

c. respectively fixing and installing fixed-focus video cameras at more than two sites on one side of the landing areas, an overlapping field of view of the video cameras at multiple sites covering the survey area where the aircraft or the unmanned aerial vehicle approaches according to guiding requests, and, where the landing areas are narrow and long, fixing and installing multiple sets of fixed-focus video cameras, fields of view of the video cameras at the multiple sites respectively overlapping to cover the survey area from a far end to a near end; and

d. installing tripod heads respectively at two sites on one side of the landing areas, each tripod head having a zooming video camera installed thereon, and according to guiding requests, during an approaching process of the aircraft or the unmanned aerial vehicle, scanning and covering the survey area through an overlapping field of view of the two video cameras as the aircraft moves by controlling rotation of the tripod heads and zooming of the video cameras.

2. The method of claim 1, wherein when multiple sets of fixed-focus video cameras are used for surveying the survey area, the survey area is divided into multiple areas for arranging surveying video camera sets respectively, wherein:

distant-field video cameras acquire images and detects the aircraft or the unmanned aerial vehicle in real time, identify and extract target features of the aircraft or the unmanned aerial vehicle, and then compute movement parameters of the aircraft or the unmanned aerial vehicle;

when it is computed that the aircraft or the unmanned aerial vehicle has entered an overlapping survey area of middle-field video cameras, the middle-field video cameras are controlled by a switch command to acquire images and detect the aircraft or the unmanned aerial vehicle in real time, identify and extract features of the aircraft or the unmanned aerial vehicle, and compute movement parameters of the aircraft or the unmanned aerial vehicle; and

guiding survey proceeds in this manner and completes when the aircraft or the unmanned aerial vehicle moves away from the survey area.

3. The method of claim 1, wherein when the zooming video cameras are used and the tripod heads are used to control directions of the video cameras,

first the video cameras are directed towards a starting position of the survey area, acquire images and detect the aircraft or the unmanned aerial vehicle in real time, identify and extract features of the aircraft or the unmanned aerial vehicle, and compute movement parameters of the the aircraft or the unmanned aerial vehicle;

based on the position of the aircraft or the unmanned aerial vehicle and the result of velocity computation, the rotation angle and velocity of the tripod heads are controlled, and the focal length of the video cameras is adjusted, so as to ensure that a clear image of the aircraft or the unmanned aerial vehicle is formed in the fields of view of the video cameras;

in the overall process, features of the aircraft or the unmanned aerial vehicle are identified and extracted, movement parameters of the aircraft or the unmanned aerial vehicle are computed and rotation of the tripod heads and zooming of the video camera lens are controlled in real time; and

guiding survey completes when the aircraft or the unmanned aerial vehicle moves away from the survey area.