Method and apparatus for enhancing vehicle navigation through recognition of geographical region types

• US 5,731,978 A
• Filed: 06/07/1995
• Issued: 03/24/1998
• Est. Priority Date: 06/07/1995
• Status: Expired due to Term

• Current Assignee: TomTom International BV (TomTom NV)
• Original Assignee: Zexel Corporation
• Inventors: White, Laura L., Desai, Simon, Tamai, Haruhisa
• Primary Examiner(s): PARK, COLLIN
• Application Number:
  US08/480,759
• Time in Patent Office: 1,021 Days
• Field of Search: 364/424.027, 364/424.029, 364/424.031, 364/443, 364/444.1, 364/444.2, 364/449.2, 364/449.3, 364/449.4, 364/449.6, 364/450, 340/990, 340/995, 340/988, 342/357, 342/450
• US Class Current: 701/201
• CPC Class Codes: G01C 21/3461 Preferred or disfavoured areas, e.g. dangerous zones, toll or emission zones, intersections, manoeuvre types, segments such as motorways, toll roads, ferries

Abstract

A method for navigating with a vehicle navigation system using recognition of geographical region types in a map database. The system'"'"'s map database stores information representative of a plurality of geographical region types. A geographical region type of a geographical region in which the navigation algorithm is operating is determined. At least one parameter related to the navigation algorithm is then set to correspond to the geographical region type. Navigation is performed using the navigation algorithm. Throughout the operation of the navigation algorithm, the system repeatedly determines whether the geographical region type has changed, and if so, changes the algorithm parameter(s) to correspond to the new geographical region type.

Claims

1. A method for navigating using a vehicle navigation system having a map database, the map database having information stored therein which is representative of a plurality of geographical region types, the vehicle navigation system employing a navigation algorithm, the method comprising the steps of:

(A) determining a geographical region type of a geographical region in which the navigation algorithm is currently operating;

(B) setting a first parameter related to the navigation algorithm to correspond to the geographical region type;

(C) navigating using the navigation algorithm with the first parameter;

(D) determining whether the geographical region type has changed to a different geographical region type;

(E) changing the first parameter to correspond to the different geographical region type if the geographical region type has changed; and

(F) repeating steps (C)-(E) while the navigation algorithm is operating.

2. The method of claim 1 wherein the plurality of geographical region types comprises fully digitized regions and sparsely digitized regions.

3. The method of claim 2 wherein the navigation algorithm comprises a route determination algorithm.

4. The method of claim 3 wherein the first parameter comprises segment costs assigned to road segments and node costs assigned to intersections.

5. The method of claim 2 wherein the navigation algorithm comprises a maneuver generation algorithm.

6. The method of claim 5 wherein the first parameter comprises a level of detail of route maneuvers to be communicated to a user of the vehicle navigation system.

7. The method of claim 2 wherein the navigation algorithm comprises a vehicle positioning algorithm.

8. The method of claim 7 wherein the first parameter comprises a region which includes possible vehicle positions.

9. The method of claim 2 wherein step (A) comprises analyzing at least one database characteristic in the geographical region to determine the geographical region type.

10. The method of claim 9 wherein the at least one database characteristic is taken from the group comprising density of roads and types of roads.

11. The method of claim 1 wherein the plurality of geographical region types comprises grid pattern regions and non-grid pattern regions.

12. The method of claim 11 wherein the navigation algorithm comprises a vehicle positioning algorithm.

13. The method of claim 12 wherein the first parameter comprises a region which includes possible vehicle positions.

14. The method of claim 12 wherein the first parameter comprises a global positioning satellite (GPS) signal.

15. The method of claim 11 wherein the navigation algorithm comprises a route determining algorithm.

16. The method of claim 15 wherein the first parameter comprises segment costs assigned to road segments and node costs assigned to intersections.

17. The method of claim 11 wherein step (A) comprises analyzing at least one database characteristic in the geographical region to determine the geographical region type.

18. The method of claim 17 wherein the at least one database characteristic is taken from the group comprising distances between intersections, angles between road segments at intersections, and curvature of roads.

19. A vehicle navigation system comprising:

a plurality of sensors for generating signals corresponding to heading and direction;

a map database for storing information which is representative of a plurality of geographical region types; and

a data processing module which is operable to;

determine a geographical region type of a geographical region in which a navigation algorithm employed by the vehicle navigation system is currently operating;

set a first parameter related to the navigation algorithm to correspond to the geographical region type;

navigate using the signals generated by the sensors and the navigation algorithm with the first parameter;

determine whether the geographical region type has changed to a different geographical region type; and

change the first parameter to correspond to the different geographical region type if the geographical region type has changed.

20. A method for determining a route using a vehicle navigation system having a map database, the map database having information stored therein which is representative of fully digitized regions and sparsely digitized regions, the vehicle navigation system employing a route determination algorithm, the method comprising the steps of:

(A) determining whether a current region in which the route determination algorithm is operating is a fully digitized region or a sparsely digitized region;

(B) setting a first parameter related to the route determination algorithm to correspond to the current region;

(C) determining a portion of the route using the route determination algorithm with the first parameter;

(D) determining whether the current region has changed to a different region;

(E) changing the first parameter to correspond to the different region if the current region has changed; and

(F) repeating steps (C)-(E) until the route is fully determined.

21. The method of claim 20 wherein the first parameter comprises segment costs assigned to road segments and node costs assigned to intersections.

22. A method for generating maneuver instructions using a vehicle navigation system having a map database, the map database having information stored therein which is representative of fully digitized regions and sparsely digitized regions, the vehicle navigation system employing a maneuver generation algorithm, the method comprising the steps of:

(A) determining whether a current region in which the maneuver generation algorithm is operating is a fully digitized region or a sparsely digitized region;

(B) setting a first parameter related to the maneuver generation algorithm to correspond to the current region;

(C) generating maneuvers for a portion of the route using the maneuver generation algorithm with the first parameter;

(D) determining whether the current region has changed to a different region;

(E) changing the first parameter to correspond to the different region if the current region has changed; and

(F) repeating steps (C)-(E) until all maneuvers for a route are determined.

23. The method of claim 22 wherein the first parameter comprises a level of detail of route maneuvers to be communicated to a user of the vehicle navigation system.

24. A method for monitoring a vehicle'"'"'s position using a vehicle navigation system having a map database, the map database having information stored therein which is representative of fully digitized regions and sparsely digitized regions, the vehicle navigation system employing a vehicle positioning algorithm, the method comprising the steps of:

(A) determining whether a current region in which the vehicle positioning algorithm is operating is a fully digitized region or a sparsely digitized region;

(B) setting a first parameter related to the vehicle positioning algorithm to correspond to the current region;

(C) determining the vehicle'"'"'s position using the vehicle positioning algorithm with the first parameter;

(D) determining whether the current region has changed to a different region;

(E) changing the first parameter to correspond to the different region if the current region has changed; and

(F) repeating steps (C)-(E) while the vehicle positioning algorithm is operating.

25. The method of claim 24 wherein the first parameter comprises a region which includes possible vehicle positions.

26. A method for monitoring a vehicle'"'"'s position using a vehicle navigation system having a map database, the map database having information stored therein which is representative of grid pattern regions and non-grid pattern regions, the vehicle navigation system employing a vehicle positioning algorithm, the method comprising the steps of:

(A) determining whether a current region in which the vehicle positioning algorithm is operating is a grid pattern region or a non-grid pattern region;

(B) setting a first parameter related to the vehicle positioning algorithm to correspond to the current region;

(C) determining the vehicle'"'"'s position using the vehicle positioning algorithm with the first parameter;

(D) determining whether the current region has changed to a different region;

(E) changing the first parameter to correspond to the different region if the current region has changed; and

(F) repeating steps (C)-(E).

27. The method of claim 26 wherein the first parameter comprises a region which includes possible vehicle positions.

28. The method of claim 26 wherein the first parameter comprises a global positioning satellite (GPS) signal.

29. A method for determining a route using a vehicle navigation system having a map database, the map database having information stored therein which is representative of grid pattern regions and non-grid pattern regions, the vehicle navigation system employing a route determination algorithm, the method comprising the steps of:

(A) determining whether a current region in which the route determination algorithm is operating is a grid pattern region or a non-grid pattern region;

(B) setting a first parameter related to the route determination algorithm to correspond to the current region;

(C) determining a portion of the route using the route determination algorithm with the first parameter;

(D) determining whether the current region has changed to a different region;

(E) changing the first parameter to correspond to the different region if the current region has changed; and

(F) repeating steps (C)-(E) until the route is fully determined.

30. The method of claim 29 wherein the first parameter comprises segment costs assigned to road segments and node costs assigned to intersections.

31. A method for improving the efficiency with which an algorithm operates in a vehicle navigation system having a map database, the map database having information stored therein which is representative of a plurality of geographical region types, the method comprising the steps of:

(A) determining a geographical region type of a geographical region in which the algorithm is currently operating;

(B) setting a first parameter related to the algorithm to correspond to the geographical region type;

(C) operating the vehicle navigation system using the algorithm with the first parameter;

(D) determining whether the geographical region type has changed to a different geographical region type;

(E) changing the first parameter to correspond to the different geographical region type if the geographical region type has changed; and

(F) repeating steps (C)-(E) while the algorithm is operating.