Method and System for Representing Pedestrian Crosswalks in a Geographic Database Used by a Navigation System

• US 20090292457A1
• Filed: 05/21/2008
• Published: 11/26/2009
• Est. Priority Date: 05/21/2008
• Status: Active Grant

• Current Assignee: HERE Global B.V. (Nokia Corporation)
• Original Assignee: Navteq North America LLC (Nokia Corporation)
• Inventors: Mays, Joseph, McGrath, Suzanne M., Ford, Paul T.
• Granted Patent: US 8,738,291 B2
• Time in Patent Office: Days
• US Class Current: 701/200
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network

Abstract

A geographic database used by a navigation system includes data regarding which corners of an intersection are connected by a crosswalk and the type of crosswalk. The geographic database also includes data regarding locations of crosswalks at a location other than an intersection. Using this information, the navigation system can provide crosswalk information to a pedestrian regarding where to cross a road.

Claims

1. A geographic database that represents a road network in a geographic area, comprising:

data entities that represent road segments;

data entities that represent nodes located at both endpoints of the road segments, wherein at least one node represents a location of an intersection of at least two roads represented by the road segments;

data representing corners located at the intersection; and

data identifying whether a crosswalk connects two of the corners located at the intersection.

2. The geographic database of claim 1, further comprising data representing a type of crosswalk connecting two corners of the intersection.

3. The geographic database of claim 2, wherein the type of crosswalk is based on crosswalk markings located on a road.

4. The geographic database of claim 3, wherein the crosswalk markings are selected from the group consisting of solid, standard, continental, dashed, zebra, and ladder.

5. The geographic database of claim 2, wherein the type of crosswalk is based on presence of at least one of a pedestrian tunnel, a pedestrian bridge, a crossing light, and a crossing signal.

6. The geographic database of claim 1, wherein the data representing the corners located at the intersection is associated with the data entities that represent the road segments.

7. The geographic database of claim 1, wherein the data representing the corners located at the intersection includes a reference to an identifier of a road segment located closest to the corner in a circular manner.

8. The geographic database of claim 1, wherein the data identifying whether a crosswalk connects two corners located at the intersection includes a pair of corner labels associated with the two corners connected by the crosswalk.

9. The geographic database of claim 8, wherein the pair of corner labels includes data associated with the road segments that form the intersection.

10. A geographic database that represents a road network in a geographic area, comprising:

data entities that represent road segments;

data entities that represent nodes located at both endpoints of the road segments, wherein at least one node represents a location of an intersection of at least two roads represented by the road segments;

data representing corners located at the intersection that includes a corner label identifying a road segment located closest to the corner in a circular manner; and

when a crosswalk is located at the intersection, data representing a pair of corner labels that identifies the two corners connected by the crosswalk.

11. The geographic database of claim 10, further comprising data representing a type of crosswalk connecting the two corners of the intersection.

12. The geographic database of claim 11, wherein the type of crosswalk is based on crosswalk markings located on a road.

13. The geographic database of claim 12, wherein the crosswalk markings are selected from the group consisting of solid, standard, continental, dashed, zebra, and ladder.

14. The geographic database of claim 11, wherein the type of crosswalk is based on presence of at least one of a pedestrian tunnel, a pedestrian bridge, a crossing light, and a crossing signal.

15. A method for representing crosswalks in a geographical database for use by a navigation system, comprising:

identifying an intersection having at least one crosswalk;

identifying road segments associated with the intersection;

storing an identifier for each of the road segments associated with the intersection in the geographic database;

storing a label for each corner of the intersection, wherein the label is based on the road segment identifier associated with the road segment located closest to the corner in a circular manner; and

representing a crosswalk using a pair of corner labels that identify the two corners connected by the crosswalk.

16. The method of claim 15, further comprising storing data identifying a type of crosswalk.

17. The method of claim 16, wherein the type of crosswalk is based on crosswalk markings located on a road.

18. The method of claim 17, wherein the crosswalk markings are selected from the group consisting of solid, standard, continental, dashed, zebra, and ladder.

19. The method of claim 16, wherein the type of crosswalk is based on presence of at least one of a pedestrian tunnel, a pedestrian bridge, a crossing sight, and a crossing signal.

20. The method of claim 15, further comprising storing an identifier for a node that represents the intersection, wherein the label is further based on the node identifier associated with the intersection.

21. A method for providing crosswalk guidance to an end-user of a navigation system, comprising:

as the end-user approaches an intersection, determining whether a crosswalk is located between two corners of the intersection;

if a crosswalk is located between two corners of the intersection, retrieving geographic data from a geographic database representing the two corners and a type of crosswalk;

providing the end-user information regarding the crosswalk based on the retrieved geographic data.

22. The method of claim 21, wherein the geographic data representing the two corners includes data associated with road segments that form the intersection.

23. The method of claim 21, wherein the geographic data representing the two corners includes a pair of corner labels.

24. The method of claim 23, wherein each of the corner labels includes a reference to an identifier of a road segment located closest to the respective corner in a circular manner.