Method and system for providing routing guidance

• US 6,278,942 B1
• Filed: 03/21/2000
• Issued: 08/21/2001
• Est. Priority Date: 03/21/2000
• Status: Expired due to Term

• Current Assignee: HERE Global B.V. (Nokia Corporation)
• Original Assignee: Navigation Technologies Corp. (Nokia Corporation)
• Inventors: McDonough, William
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc-Coleman, Marthe
• Application Number:
  US09/531,574
• Time in Patent Office: 518 Days
• Field of Search: 701/209, 701/210, 701/202, 701/207, 701/208, 701/211, 701/200, 701/201, 340/990, 340/988, 340/995
• US Class Current: 701/210
• CPC Class Codes: G01C 21/3415 Dynamic re-routing, e.g. recalculating the route when the user deviates from calculated route or after detecting real-time traffic data or accidents
• CPC Class Codes: G08G 1/096827 where the route is computed onboard
• CPC Class Codes: G08G 1/096861 where the immediate route instructions are output to the driver, e.g. arrow signs for next turn

Abstract

A method performed by a navigation system to provide guidance to a driver of a vehicle when the vehicle departs from a route to a destination for which route guidance was being provided by the navigation system. Intersections that can be reached by the vehicle while calculation of a new solution route to the destination is being performed are identified. For each identified intersection, cost factors associated with the possible paths leading from the identified intersection are modified to increase the likelihood that the new solution route include those paths with the least cost factors.

Claims

1. A method of providing guidance with a navigation system to a user of said navigation system when a vehicle in which the user is located deviates from a route to a destination for which route guidance was previously being provided by the navigation system, the method comprising the steps of:

upon detecting that the vehicle has deviated from the route for which the user had been receiving route guidance, calculating a new route to the destination from a current location of said vehicle;

wherein during said calculating step, for those intersections that can be encountered by said vehicle from said current position while said calculating is being performed, adjusting relative cost factors associated with paths leading from said intersections to increase a probability that the new route will include a path from the current position that the user is likely to take.

2. The method of claim 1 further comprising:

providing the user with guidance for following the new route.

3. The method of claim 1 wherein said step of relatively adjusting comprises:

multiplying a cost factor associated with each of said paths by a constant.

4. The method of claim 3 wherein said constant is 10.

5. The method of claim 1 wherein each of said cost factors is expressed in seconds associated with taking an associated path from an intersection.

6. The method of claim 1 wherein said cost factors are included in a geographic database used by the navigation system.

7. The method of claim 6 wherein said geographic database is installed in the vehicle.

8. A method of providing guidance with a navigation system to a user of the navigation system when a vehicle in which the user is located departs from a route to a destination for which route guidance was being provided by the navigation system, the method comprising the steps of:

identifying intersections within a threshold that can be reached by the vehicle while calculation of a new solution route to the destination is being performed;

predicting a most likely path that the vehicle will take from each of said identified intersections; and

calculating a new solution route that includes the most likely path from each of said identified intersections.

9. The method of claim 8 wherein said step of predicting comprises:

adjusting turn costs associated with each path leading from said identified intersections.

10. The method of claim 9 wherein each of said turn costs is expressed in seconds.

11. The method of claim 9 wherein said turn costs are included in a geographic database used by the navigation system.

12. The method of claim 11 wherein said geographic database is installed in the vehicle.

13. The method of claim 8 further comprising:

providing the user with guidance for following the new solution route.

14. The method of claim 8 wherein said step of predicting comprises:

multiplying a cost factor associated with each path from each said identified intersections by a constant.

15. The method of claim 14 wherein said constant is 10.

16. A method of using a navigation system that uses a geographic database to predict where a vehicle will be after the vehicle has deviated from a first route to a destination for which route guidance was being provided by the navigation system, the method comprising the steps of:

identifying intersections that can be reached by the vehicle while calculation of a new solution route to the destination is being performed by the navigation system;

identifying turn costs associated with possible paths leading from each of said identified intersections, wherein said turn costs are included in the geographic database;

temporarily modifying said turn costs; and

calculating a second route using said temporarily modified turn costs.

17. The method of claim 16 further comprising:

providing a user of the navigation system with guidance for following the second route.

18. The method of claim 16 wherein said step of temporarily modifying comprises:

multiplying said turn costs by a factor.

19. The method of claim 16 wherein said step of temporarily modifying comprises:

multiplying said turn costs by a relatively large number.