Method of estimating an ability of a vehicle to reach a target road segment, method of generating a database, and navigation system

• US 9,091,560 B2
• Filed: 07/15/2013
• Issued: 07/28/2015
• Est. Priority Date: 07/13/2012
• Status: Active Grant

• Current Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman Becker Automotive Systems GmbH (Samsung Electronics Co. Ltd.)
• Inventors: Kluge, Sebastian, Engelhardt, Hans-Peter
• Primary Examiner(s): Cheung, Calvin
• Assistant Examiner(s): SCHNEIDER, PAULA LYNN
• Application Number:
  US13/942,228
• Publication Number:
  US 20140019041A1
• Time in Patent Office: 743 Days
• Field of Search: 701/430, 701/527, 701/533
• US Class Current: 1/1
• CPC Class Codes: G01C 21/3469 Fuel consumption; Energy use; Emission aspects

Abstract

Various embodiments relate to a method of estimating an ability of a vehicle to reach a target road segment, comprising retrieving road segment data for road segments containing previously generated route information for routes connecting the road segments, the route information parameterizing costs associated for travelling along the respective route); and establishing first road segment data for the target road segment indicating a gateway road segment and indicating route information for a successive route from the gateway road segment to the target road segment. The method further comprises, based on the route information of the successive route, determining first costs for travelling along the successive route, and establishing, based on the indicated gateway road segment, second road segment data for the current road segment, the second road segment data indicating route information for an initial route from the current road segment to the gateway road segment. The method further comprises determining, based on the received route information for the initial route, second costs for travelling on the initial route and estimating, based on the determined first and second costs, the ability of the vehicle to reach the target road segment.

Claims

1. A method of estimating an ability of a vehicle to reach a target road segment, the method comprising:

retrieving, by a computing device, digital map data comprising road segments in a vicinity of a current location of the vehicle, the digital map data comprising the target road segment;

retrieving, by the computing device, road segment data for at least some of the road segments from a database, the road segment data containing previously generated route information for routes connecting the road segments, the route information parameterizing costs for travelling along the respective route;

establishing, by the computing device, a current road segment based on a current location of the vehicle;

establishing, by the computing device, from the retrieved road segment data, first road segment data for the target road segment, the first road segment data indicating a gateway road segment and indicating the route information for a successive route from the gateway road segment to the target road segment;

determining, by the computing device, based on the route information for the successive route, first costs for travelling on the successive route;

establishing, by the computing device, based on the indicated gateway road segment, second road segment data for the current road segment, the second road segment data indicating route information for an initial route from the current road segment to the gateway road segment;

determining, by the computing device, based on the route information for the initial route, second costs for travelling on the initial route; and

estimating, by the computing device, based on the determined first and second costs, the ability of the vehicle to reach the target road segment.

2. The method of claim 1, wherein the costs comprise parameterize energy consumption costs for travelling along the respective route or parameterize travel time costs for travelling along the respective route or a combination thereof.

3. The method of claim 2, wherein the second road segment data is established from the retrieved road segment data;

wherein the establishing of the second road segment data comprises

performing a road network search to obtain the initial route from the current road segment to the gateway road segment; and

determining the route information for the initial route.

4. The method of claim 3, comprising:

estimating the cruising range of the vehicle based on the estimated ability of the vehicle to reach the plurality of target road segments.

5. The method of claim 4, further comprising:

determining the third geographical area having the inner boundaries being defined by a lower threshold of costs associated with reaching the inner boundaries and having outer boundaries being defined by an upper threshold of cost associated with reaching the outer boundaries.

6. The method of claim 4, wherein the third geographical area is indicated in the road segment data.

7. The method of claim 4, further comprising:

checking a validity of the database, the validity indicating whether the routes of the route information are outdated, wherein the checking is based on elements selected from the group consisting of a distance between a location of the vehicle at the time the database was generated and the current location;

a distance between gateway road segments and the current location; and

a distance between a previously estimated cruising range and the estimated cruising range;

wherein the method further comprises selectively generating a new database based on the checking of the validity.

8. The method of claim 7, wherein the new database is generated in a background process and the cruising range is estimated based on the database until the generating of the new database is completed.

9. A method of generating a database for estimating a cruising range of a vehicle, the method comprising:

retrieving, by a computing device, digital map data comprising road segments from a map database in a vicinity of a current location of the vehicle;

determining, by the computing device, based on the digital map data, a first geographical area and a second geographical area, wherein the first geographical area is a connected area comprising the current location, and wherein the second geographical area surrounds the first geographical area;

determining, by the computing device, a plurality of gateway road segments based on their distance to the boundary between the first and second geographical areas;

for at least one road segment situated in the first geographical area, performing, by the computing device, a road network search to obtain first routes from the respective road segments to each of the plurality of gateway road segments and buffering the obtained first routes as initial routes;

for each of the plurality of gateway road segments, continuing, by the computing device, the road network search to obtain second routes from the plurality of gateway road segments to at least one road segment situated in the second geographical area, and

for the at least one road segment situated in the second geographical area, buffering, by the computing device, one of the obtained second routes as successive route, the successive route being the second route having minimized costs for travelling between any one of the plurality of gateway road segments and the respective at least one road segment situated in the second geographical area;

determining, by the computing device, route information for the buffered initial routes and successive routes, the route information parameterizing associated costs for travelling along the respective routes and indicating the respective gateway road segment associated with the respective route;

for the at least one road segment situated in the second geographical area, storing, by the computing device, in the database the determined route information for the buffered successive route as road segment data.

10. The method of claim 9, further comprising:

for the at least one road segment situated in the first geographical area, storing in the database the determined route information for the buffered initial routes as road segment data.

11. The method of claim 9, further comprising:

for each of the plurality of gateway road segments, performing a reverse road network search to obtain first routes for a plurality of road segments situated in the first geographical area to each of the plurality of gateway road segments and buffering the obtained first routes as initial routes; and

for the plurality of road segments situated in the first geographical area, storing in the database the determined route information for the buffered successive routes as road segment data.

12. The method of claim 11, further comprising:

determining an approximated cruising range of the vehicle, wherein the determining of the first and second geographical areas is based on the approximated cruising range.

13. The method of claim 9, further comprising:

determining a third geographical area, the third geographical area being a fragment of the second geographical area and having inner boundaries being defined by a lower threshold of costs associated with reaching the inner boundaries and having outer boundaries being defined by an upper threshold of cost associated with reaching the outer boundaries,

wherein the determined route information is buffered and/or stored for those road segments situated in the second and third geographical areas.

14. The method of claim 9, further comprising:

estimating a cruising range of the vehicle based on costs required for travelling along the road segments,

wherein the determined route information is buffered and/or stored for those road segments situated in the second geographical area and which are situated in a proximity of the estimated cruising range.

15. A navigation system of a vehicle, the navigation system, comprising:

a positioning unit configured to determine a current location of the vehicle;

a map database comprising map data of road segments;

a database being configured to store road segment data for the road segments, the road segment data containing previously generated route information for routes connecting the road segments, the route information parameterizing costs associated for travelling along the respective route;

a processor configured to perform the steps of

retrieving digital map data comprising road segments in a vicinity of a current location of the vehicle, the map data comprising the target road segment;

retrieving road segment data for at least some of the road segments from a database;

establishing a current road segment based on the current location of the vehicle;

establishing, from the retrieved road segment data, first road segment data for the target road segment, the first road segment data indicating a gateway road segment and indicating the route information for a successive route from the gateway road segment to the target road segment;

determining, based on the route information for the successive route, first costs for travelling on the successive route;

establishing, based on the indicated gateway road segment, second road segment data for the current road segment, the second road segment data indicating route information for an initial route from the current road segment to the gateway road segment;

determining, based on the route information for the initial route, second costs for travelling on the initial route; and

estimating, based on the determined first and second costs, the ability of the vehicle to reach the target road segment.