Method and system for aircraft taxi strike alerting

Patent metadata

Field	Value
Publication number	US-11521504-B2
Application number	US-202016822999-A
Country	US
Kind code	B2
Filing date	Mar 18, 2020
Priority date	Mar 18, 2020
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

Apparatus and associated methods relate to ranging object(s) nearby an aircraft using triangulation. A light projector mounted at a projector location on the aircraft projects pulses of polarized light onto the scene external to the aircraft. The projected pulses of polarized light are polarized in a first polarization state. A camera mounted at a camera location on the aircraft has a shutter synchronized to the projector output pulse and receives a portion of the projected pulses of polarized light reflected by the object(s) in the scene and polarized at a second polarization state orthogonal to the first polarization state. Location(s) and/or range(s) of the object(s) is calculated, based on the projector location, the camera location, and pixel location(s) upon which the portion of light is imaged.

First claim

The invention claimed is:

1. A system for calculating location(s) and/or range(s) of object(s) in a scene external to a vehicle, the system comprising:
a light projector configured to be mounted at a projector location on the vehicle to project pulses of polarized light onto the scene;
a lens configured to collimate the pulses of polarized light projected in a collimated direction orthogonal to a direction of projection, and to diverge the pulses of polarized light in a divergent direction orthogonal to both the collimated direction and the direction of projection;
a polarizing filter configured to pass light of a detection polarization state orthogonal to the specular-reflection polarization state and to block light of the specular-reflection polarization state, the specular-reflection polarization state being the polarization state of the projected pulses of polarized light reflected by specular objects;
a camera having a two-dimensional array of light-sensitive pixels, the camera configured to be mounted at a camera location on the vehicle to receive light passed through the polarizing filter so as to capture two-dimensional images of the scene;
a controller configured to coordinate the light projector and the camera so that the two-dimensional images of the scene include image data corresponding to a received portion of the projected pulses of polarized light reflected by the scene and passed through the polarizing filter; and
an image processor configured to calculate, based on the projector location, the camera location, and the image data, locations(s) and/or range(s) of the object(s) in the scene.

2. The system of claim 1 , wherein the image processor is further configured to determine a subset of the two-dimensional array of pixels upon which the portion of the received portion of the projected pulses of light reflected by the scene and passed through the polarizing filter is focused.

3. The system of claim 2 , wherein the image data includes the determined subset, each of the determined subset has a pixel coordinate indicative of a reception angle of field of view from which the received portion of the projected pulses of light reflected by the scene and passed through the polarizing filter is received.

4. The system of claim 1 , wherein the image data includes a pixel coordinate(s) upon which the received portion of the projected pulses of polarized light reflected by the scene and passed through the polarizing filter is focused.

5. The system of claim 1 , wherein the camera is oriented such that the image data of the received portion of the collimated pulses of polarized light reflected by the scene and passed through the polarizing filter is imaged by a selected one of rows or columns of the two-dimensional array of light-sensitive pixels.

6. The system of claim 5 , wherein the projector location is on a line along which one of the rows or columns of light-sensitive pixels is located.

7. The system of claim 6 , wherein the controller is further configured to control an angular direction along which the pulses of light are projected, wherein the line along which one of the rows or columns of light-sensitive pixels is located defines an angular control axis about which the angular direction along which the pulses of polarized light are projected.

8. The system of claim 1 , wherein the camera is configured to form a first image while the light projector is projecting a pulse of light onto the scene.

9. The system of claim 8 , wherein the camera is configured to form a second image while the light projector is not projecting a pulse of light onto the scene.

10. The system of claim 9 , wherein the image processor is configured to generate a difference image based on a difference between the first and second images.

11. The system of claim 1 , further comprising a cockpit notification system configured to generate an alert signal if the calculated location(s) and/or range(s) of object(s) indicate that the object(s) are within a collision zone or on a collision trajectory.

12. The system of claim 11 , wherein the cockpit notification system includes an audible alarm that is activated when the calculated location(s) and/or range(s) of the object(s) indicates one or more of the object(s) in the scene has a combination of location(s) and/or ranges(s) relative to the vehicle corresponding to a risk of collision.

13. The system of claim 11 , wherein the cockpit notification system includes a display device configured to display a two-dimensional image of the scene annotated with the calculated location(s) and/or range(s) of object(s).

14. A method for calculating location(s) and/or range(s) of object(s) in a scene external to a vehicle, the method comprising:
projecting, via a light projector mounted at a projector location on the vehicle, pulses of polarized light onto the scene;
collimating, via a lens, the pulses of polarized light projected in a collimated direction orthogonal to a direction of projection;
diverging the pulses of polarized light in a divergent direction orthogonal to both the collimated direction and the direction of projection;
polarizing, via a polarizing filter, a received portion of the projected pulses of polarized light reflected by the scene so as to block light of the specular-reflection polarization while passed light of a detection polarization state orthogonal to the specular-reflection polarization state, the specular-reflection polarization state being the polarization state of the projected pulses of polarized light reflected by specular objects;
capturing, via a camera having a two-dimensional array of light-sensitive pixels, two-dimensional images of the scene, the camera mounted at a camera location on the vehicle to receive light passed through the polarizing filter;
coordinating, via a controller, the light projector and the camera so that the two-dimensional images of the scene include image data corresponding to a received portion of the projected pulses of polarized light reflected by the scene and passed through the polarizing filter; and
calculating, via an image processor, locations(s) and/or range(s) of object(s) in the scene based on the projector location, the camera location, and the image data, locations(s) and/or range(s) of the object(s) in the scene.

15. The method of claim 14 , further comprising:
outputting an alert signal if the calculated location(s) and/or range(s) of object(s) indicates one or more of the object(s) in the scene has a combination of a location(s) and/or range(s) relative to the vehicle corresponding to a risk of collision.

16. The method of claim 14 , further comprising:
determining, via the image processor, a subset of the two-dimensional array of pixels upon which the portion of the received portion of the projected pulses of light reflected by the scene and passed through the polarizing filter is focused.

17. The method of claim 16 , wherein the image data includes the determined subset, each of the determined subset has a pixel coordinate indicative of a reception angle of field of view from which the received portion of the projected pulses of light reflected by the scene and passed through the polarizing filter is received.

18. The method of claim 14 , wherein the image data includes a pixel coordinate(s) upon which the received portion of the projected pulses of polarized light reflected by the scene and passed through the polarizing filter is focused.

Assignees

• Rosemount Aerospace Inc

Inventors

• Rutkiewicz Robert
• Pesik Joseph T

Classifications

• G01B11/2513 Primary

  with several lines being projected in more than one direction, e.g. grids, patterns · CPC title

• G06V20/58

  Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads · CPC title

• G06V10/141

  Control of illumination · CPC title

• G06V10/25

  Determination of region of interest [ROI] or a volume of interest [VOI] · CPC title

• G06V10/147

  Details of sensors, e.g. sensor lenses (fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19) · CPC title