Probabilistic landmark navigation (PLN) system

Patent metadata

Field	Value
Publication number	US-10977953-B2
Application number	US-201815897311-A
Country	US
Kind code	B2
Filing date	Feb 15, 2018
Priority date	Feb 17, 2017
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

A probabilistic landmark navigation system is arranged to obtain from one or more image sensors one or more terrain images of a target terrain to be traversed by a vehicle. The terrain images are characterized by multiple individually non-distinctive terrain features without distinctively identifiable landmark features. The non-distinctive terrain features in the one or more terrain images are compared to map database information to make a non-temporal probabilistic determination of absolute location coordinates to associate with the non-distinctive terrain features. Then a navigation path is determined for the vehicle across the target terrain based on the absolute location coordinates.

First claim

What is claimed is:

1. A probabilistic landmark navigation system comprising:
at least one hardware processor; and
at least one hardware memory device operatively connected to the at least one hardware processor;
wherein the at least one hardware processor is configured to execute program instructions to:
obtain from one or more image sensors one or more terrain images of a target terrain to be traversed by a vehicle, wherein the one or more terrain images are characterized by a plurality of individually non-distinctive terrain features without distinctively identifiable landmark features;
access map database information stored in the at least one hardware memory device;
compare the plurality of non-distinctive terrain features in the one or more terrain images to the map database information to make a non-temporal probabilistic determination of absolute location coordinates to associate with the plurality of non-distinctive terrain features; and
determine a navigation path for the vehicle across the target terrain based on the absolute location coordinates.

2. The system according to claim 1 , wherein the at least one hardware processor is configured to execute the program instructions as the vehicle traverses the target terrain to dynamically determine the navigation path in real time.

3. The system according to claim 1 , wherein the at least one hardware processor is configured to execute the program instructions before the vehicle traverses the target terrain to pre-determine the navigation path.

4. The system according to claim 1 , wherein the one or more terrain images include a plurality of terrain images of the target terrain.

5. The system according to claim 1 , wherein determining the navigation path is further based on additional navigational information in addition to the absolute location coordinates.

6. The system according to claim 5 , wherein the additional navigational information is used when the non-temporal probabilistic determination of absolute location coordinates is further associated with a low reliability confidence.

7. The system according to claim 5 , wherein the additional navigational information includes information characterizing distinctively identifiable landmark features not present in the one or more terrain images.

8. The system according to claim 5 , wherein the additional navigational information includes information characterizing density of distinctively identifiable landmark features present along the navigation path so as to favor directing the navigation path through greater density so as to improve navigational reliability.

9. A computer-implemented method employing at least one hardware implemented computer processor for probabilistic landmark navigation, the method comprising:
operating the at least one hardware processor to execute program instructions to:
obtain from one or more image sensors one or more terrain images of a target terrain to be traversed by a vehicle, wherein the one or more terrain images are characterized by a plurality of individually non-distinctive terrain features without distinctively identifiable landmark features;
access map database information stored in at least one hardware memory device;
compare the plurality of non-distinctive terrain features in the one or more terrain images to the map database information to make a non-temporal probabilistic determination of absolute location coordinates to associate with the plurality of non-distinctive terrain features; and
determine a navigation path for the vehicle across the target terrain based on the absolute location coordinates.

10. The method according to claim 9 , wherein the navigation path is dynamically determined in real time as the vehicle traverses the target terrain.

11. The method according to claim 9 , wherein the navigation path is pre-determined before the vehicle traverses the target terrain.

12. The method according to claim 9 , wherein the one or more terrain images include a plurality of terrain images of the target terrain.

13. The method according to claim 9 , wherein determining the navigation path is further based on additional navigational information in addition to the absolute location coordinates.

14. The method according to claim 13 , wherein the additional navigational information is used when the non-temporal probabilistic determination of absolute location coordinates is further associated with a low reliability confidence.

15. The method according to claim 13 , wherein the additional navigational information includes information characterizing distinctively identifiable landmark features not present in the one or more terrain images.

16. The method according to claim 13 , wherein the additional navigational information includes information characterizing density of distinctively identifiable landmark features present along the navigation path so as to favor directing the navigation path through greater density so as to improve navigational reliability.

17. A computer program product encoded in a non-transitory computer-readable medium, which when executed by a computer causes the computer to perform the following operations:
obtain from one or more image sensors one or more terrain images of a target terrain to be traversed by a vehicle, wherein the one or more terrain images are characterized by a plurality of individually non-distinctive terrain features without distinctively identifiable landmark features;
access map database information stored in at least one hardware memory device;
compare the plurality of non-distinctive terrain features in the one or more terrain images to the map database information to make a non-temporal probabilistic determination of absolute location coordinates to associate with the plurality of non-distinctive terrain features; and
determine a navigation path for the vehicle across the target terrain based on the absolute location coordinates.

18. The computer program product according to claim 17 , wherein the navigation path is dynamically determined in real time as the vehicle traverses the target terrain.

19. The computer program product according to claim 17 , wherein the navigation path is pre-determined before the vehicle traverses the target terrain.

20. The computer program product according to claim 17 , wherein the one or more terrain images include a plurality of terrain images of the target terrain.

21. The computer program product according to claim 17 , wherein determining the navigation path is further based on additional navigational information in addition to the absolute location coordinates.

22. The computer program product according to claim 19 , wherein the additional navigational information is used when the non-temporal probabilistic determination of absolute location coordinates is further associated with a low reliability confidence.

23. The computer program product according to claim 19 , wherein the additional navigational information includes information characterizing distinctively identifiable landmark features not present in the one or more terrain images.

24. The computer program product according to claim 19 , wherein the additional navigational information includes information characterizing density of distinctively identifiable landmark features present along the navigation path so as to favor directing the navigation path through greater density so as to improve navigational reliability.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Laine Juha-Pekka J
• Bortolami Simone B
• Kinast Joseph M
• Arant Charles F
• Smith Stephen P

Classifications

• G01C11/06 Primary

  by comparison of two or more pictures of the same area · CPC title

• G08G5/74

  for monitoring terrain · CPC title

• G08G5/55

  for a single aircraft · CPC title

• G08G5/50

  Navigation or guidance aids · CPC title

• G01C21/30

  Map- or contour-matching · CPC title