Database comprising topographical information on obstacles and method for generating one such database

• US 8,244,424 B2
• Filed: 11/06/2006
• Issued: 08/14/2012
• Est. Priority Date: 11/10/2005
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Subelet, Michel, Fontaine, Sylvain
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): Marc, McDieunel
• Application Number:
  US12/093,119
• Publication Number:
  US 20090182764A1
• Time in Patent Office: 2,108 Days
• Field of Search: 701/1, 701/3, 701/4, 701/7, 701/8, 701/9, 701/10, 701/13, 701/14, 701/16, 701/25, 701/33, 701/36, 701/38, 701/48, 701/93, 701/117, 701/200, 701/207, 701/208, 701/213, 701/300, 701/301, 340/436, 340/901, 340/945, 340/946, 340/953, 340/961, 340/963, 340/969, 340/970, 342/26.B, 342/33, 342/61, 342/65, 342/118, 342/120, 342/175, 342/195, 342/357.31, 455/422.1, 14/25, 244/158.1, 250/330
• US Class Current: 701/24
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G08G 5/0086 for monitoring terrain radar or analogous systems specially adapted for terrain avoidance G01S13/935

Abstract

The invention relates to a database and a method of generating a database containing topographical information on obstacles distributed over a geographic area subdivided into cells. The method includes reading topographical data obtained from heterogeneous sources. Topographical data are generated which relate to pointlike obstacles from the information collected from the topographical data. Topographical data are generated which relate to linear obstacles from the information collected from the topographical data. The obstacle database is created. Each cell contains a link to the obstacles whose coordinates in the geographic area covered by the cell are recorded with an uncertainty value. In particular, the invention applies to the generation of a database on board an aircraft.

Claims

1. A method of generating a database comprising topographical information on obstacles being distributed over a geographic area, said geographic area being subdivided in the database into several geographic region levels, comprising the following steps:

(a) reading topographical data obtained from heterogeneous data source;

(b) generating by a processor topographical data relating to pointlike obstacles from the data collected in the step (a);

(c) generating by a processor topographical data relating to linear obstacles from the data collected in the step (a);

(d) creating an obstacle database;

each cell containing a link to the obstacles, each coordinate of said obstacles in the geographic area covered by said cell being recorded with an uncertainty value.

2. The method as claimed in claim 1, further comprising setting the uncertainty value to a default value when the uncertainty value of the coordinates of an obstacle is not known.

3. The method as claimed in claim 1, wherein, when generating the topographical data relating to pointlike obstacles for each cell, a link is created for each pointlike obstacle satisfying one of the following conditions:

the center of said pointlike obstacle belongs to said cell;

the area of uncertainty of said obstacle is at least partially contained in said cell.

4. The method as claimed in claim 1, wherein each end of a linear obstacle is represented by a pointlike obstacle.

5. The method as claimed in claim 4, wherein, when generating the topographical data relating to linear obstacles for each cell, a link is created for each linear obstacle satisfying one of the following conditions:

one of the ends of said linear obstacle at least partially belongs to said cell, the areas of uncertainty of the ends being included;

one of the segments defined by the ends of said linear obstacle intersects said cell;

the area of uncertainty of said linear obstacle is contained at least partially in said cell.

6. The method as claimed in claim 1, comprising a step for generating an access tree to the obstacles, the tree comprising:

a main node of level 0 from which the tree can be browsed,

nodes pointing to a geographic area, a level of each node corresponding to a level of the geographic area toward which it points;

each node comprising a link to all lower-level nodes included in the same geographic region and comprising at least one obstacle.

7. The method as claimed in claim 6, wherein each node corresponding to a cell comprises:

information on the number of pointlike obstacles present in the corresponding cell;

information on the number of linear obstacles present in the corresponding cell;

pointers to tables comprising information on the obstacles present in the corresponding cell.

8. The method as claimed in claim 1, comprising a step for generating description tables of the obstacles database, the description tables comprising information relating to the database.

9. A non-transitory computer-readable medium comprising:

a processor configured to generate topographical information on obstacles, the obstacles being distributed over a geographic area, said geographic area being subdivided into several geographic region levels comprising cells, the topographical information on obstacles comprising;

at least one Cells table comprising a line for each cell of the geographic area;

at least one Pointlike obstacles table comprising a line for each pointlike obstacle of the geographic area, said pointlike obstacle table comprising fields for specifying coordinates and height of the pointlike obstacles;

at least one Linear obstacles table comprising a line for each linear obstacle of the geographic area, said linear obstacle table comprising fields for specifying coordinates and height of the ends of the linear obstacles, each line of the Linear obstacles table comprising links to at least two lines of the Pointlike obstacles table;

each line of the Cells table comprising links to the obstacles present in the corresponding cell.

10. The non-transitory computer-readable medium as claimed in claim 9, comprising a Descriptor table of the obstacle database for storing information identifying the obstacle database loaded on board an aircraft, the date when the obstacle database was produced, and the elements needed to find and access the elements included in the other tables.

11. The non-transitory computer-readable medium as claimed in claim 10, wherein the Descriptor table of the obstacle database comprises the following fields:

serial number, production date, pointers to the tables comprising the data on the obstacles.

12. The non-transitory computer-readable medium as claimed in claim 9, comprising tables describing a tree for accessing the information on all the obstacles.

13. The non-transitory computer-readable medium as claimed in claim 9, incorporated in a terrain awareness and warning system comprising an obstacle collision prediction and warning system.