SYSTEM AND METHOD FOR DISPLAYING RUNWAYS AND TERRAIN IN SYNTHETIC VISION SYSTEMS

• US 20110095913A1
• Filed: 10/25/2010
• Published: 04/28/2011
• Est. Priority Date: 10/26/2009
• Status: Active Grant

• Current Assignee: L3Harris Aviation Products, Inc. (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Avionics Systems Incorporated (L3Harris Technologies, Inc.)
• Inventors: Seabloom, Joshua C., Painter, Brett A.
• Granted Patent: US 8,531,315 B2
• Time in Patent Office: Days
• US Class Current: 340/972
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration

Abstract

A method and system for displaying three dimensional images of runways and terrain, as well as additional information, on one or more screens of an avionics display system is provided. The system merges elevation information for terrain points and elevation information for runway points by grouping runways together that are within a threshold distance of each other. For each group, a plane is calculated. The calculated plane is then projected onto all of the runways within the group. The plane may also be projected onto a subset of neighboring terrain points. The adjusted elevation created by the projection of the plane are then used in creating the images for display on the synthetic vision display. The result is that all of the runways within a group, along with their neighboring terrain, are displayed as being coplanar.

Claims

1. A method of displaying a runway on an aircraft display in a three dimensional manner, said method comprising:

receiving information about a height of the runway;

receiving information about a height of at least one terrain point near the runway;

using the height of the runway to determine a plane;

using said plane to determine an adjusted height for the terrain point near the runway;

displaying the runway; and

displaying the terrain at said at least one terrain point as having the adjusted height.

2. The method of claim 1 further including:

receiving information about a height of a second runway;

determining if said second runway lies within a predetermined distance of said runway;

if said second runway lies within the predetermined distance, using said height information about said second runway in determining said plane; and

if said second runway lies outside the predetermined distance, using said height information about said second runway to determine a second plane, and further using said second plane to determine a second adjusted height for a second terrain point near the second runway, and displaying said second terrain point at the second adjusted height.

3. The method of claim 1 further including:

receiving information about a height of a second runway;

determining if said second runway lies within a predetermined distance of said runway; and

if said second runway lies with the predetermined distance, displaying said runway and said second runway as lying in a common plane on said display.

4. The method of claim 3 wherein said common plane is determined using first and second height values for the runway and first and second height values for the second runway.

5. The method of claim 4 wherein said common plane is defined using a least squares method that takes into account the first and second height values for the runway and the first and second height values for the second runway.

6. The method of claim 1 wherein using said plane to determine an adjusted height for the terrain point includes determining a mathematical formula for said plane and calculating the adjusted height at the terrain point using the mathematical formula.

7. The method of claim 1 further including:

receiving information about heights of a plurality of additional terrain points near the runway;

defining a plurality of triangles using said plurality of additional terrain points as vertices of said triangles;

determining if any of said runway falls within any of the triangles;

for those triangles in which said runway falls, using said plane to define adjusted heights for all three of the vertices of those triangles in which said runway falls; and

displaying all of said triangles in which said runway falls as being coplanar with said runway.

8. The method of claim 7 further including:

receiving information about a height of a second runway;

determining if said second runway lies within a predetermined distance of said runway;

if said second runway lies within the predetermined distance, using said height information about said second runway in determining said plane; and

if said second runway lies outside the predetermined distance, using said height information about said second runway to determine a second plane and displaying said second runway as being coplanar with said second plane.

9. A method of displaying a plurality of runways in a three dimensional manner on an aircraft display, said method comprising:

receiving information about a location of a first runway at an airport;

receiving information about a location of a second runway at said airport;

determining if said first and second runways lie within a threshold distance of each other; and

displaying in a three dimensional manner both said first and second runways on said aircraft display as lying within a common plane if they are within the threshold distance from each other.

10. The method of claim 9 further including, if said first and second runways are within the threshold distance, calculating the common plane based upon height information for both the first runway and the second runway.

11. The method of claim 10 wherein said height information includes at least two height values for said first runway and at least two height values for said second runway, and said calculating of the common plane utilizes a least squares method for determining the plane.

12. The method of claim 10 further including:

receiving height information about a plurality of terrain points within a vicinity of said airport;

defining a plurality of triangles using said plurality of terrain points as vertices of said triangles;

determining a first set of triangles wherein each triangle in said first set encompasses at least a portion of said first runway;

determining a second set of triangles wherein each triangle in said second set encompasses at least a portion of said second runway;

if said first and second runways are within said threshold distance, displaying all of the terrain points within said first and second sets as being coplanar with said first and second runways.

13. The method of claim 12 wherein, if said first and second runways are outside of said threshold distance, said method further includes displaying all of the terrain points within said first set as being coplanar with said first runway, and displaying all of the terrain points within said second set as being coplanar with said second runway.

14. A system for displaying three dimensional images of terrain and runways on an aircraft display, said system including:

a screen for displaying the images;

a memory containing data defining a first height of a runway at a first location and a second height of the runway at a second location, said memory further including data defining a plurality of heights for a plurality of terrain points; and

a controller in communication with the screen and the memory, said controller adapted to determine a plane using said first and second heights of said runway, said controller further adapted to project said plane onto a set of said plurality of terrain points, said controller further adapted to generate three dimensional images of said runway and the set of terrain points for displaying on said screen, said images depicting the runway and the set of terrain points as being coplanar.

15. The system of claim 14 wherein said controller determines the set of terrain points by:

defining a plurality of triangles having vertices at said terrain points;

determining a set of said triangles, said set of triangles being defined such that each triangle in said set at least partially overlaps the runway; and

defining said set of terrain points as those terrain points corresponding to all of the vertices within said set of triangles.

16. The system of claim 14 wherein said controller is further adapted to determine if said runway lies within a threshold distance of a second runway and, if said second runway lies within said threshold, said controller is further adapted to:

(a) also use height information for said second runway in determining said plane, and (b) display said second runway and said runway as being coplanar.

17. The system of claim 16 wherein said controller uses a least squares algorithm for determining said plane when said first and second runways lie within said threshold.

18. The system of claim 16 wherein said controller determines the set of terrain points by:

defining a plurality of triangles having vertices at said terrain points;

determining a set of said triangles, said set of triangles being defined such that each triangle in said set at least partially overlaps either or both of the runway and the second runway; and

defining said set of terrain points as those terrain points corresponding to all of the vertices within said set of triangles.

19. A system for displaying three dimensional images of terrain and runways on an aircraft display, said system including:

a screen for displaying the images;

a memory containing first data defining a location of a first runway and second data defining a location of a second runway; and

a controller in communication with the screen and the memory, said controller adapted determine if said first runway and said second runway lie within a threshold distance of each other, said controller further adapted to generate three dimensional images for display on said screen of said first and second runways, said images depicting the first and second runways as lying in a common plane if said first and second runways lie within the threshold distance of each other.

20. The system of claim 19 wherein said memory further includes third data defining a location of a third runway and said controller is further adapted to determine if said third runway lies within the threshold distance of either or both of said first and second runways, wherein said images depict as being coplanar any group of said first, second, or third runways that lie within the threshold distance of each other.

21. The system of claim 19 wherein said controller is adapted to determine said common plane based upon a first plurality of height values for said first runway and a second plurality of height values for said second runway.

22. The system of claim 21 wherein said controller uses a least squares method with said first and second plurality of height values for determining said common plane.

23. The system of claim 22 wherein said memory further includes height data indicating heights for a plurality of terrain points, and said controller is further adapted to display a set of said terrain points as lying in said common plane.

24. The system of claim 23 wherein said controller is adapted to determine said set of terrain points by defining a plurality of triangles using said plurality of terrain points as vertices of said triangles;

determining a set of triangles from said plurality of triangles wherein each triangle in said set of triangles encompasses at least a portion of either said first runway, said second runway, or both said first and second runways; and

defining said set of terrain points as those terrain points corresponding to the vertices within said set of triangles.