Vehicle navigation system with road link re-costing

• US 6,256,579 B1
• Filed: 07/13/1999
• Issued: 07/03/2001
• Est. Priority Date: 07/13/1999
• Status: Expired due to Fees

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Tanimoto, Satoshi
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US09/352,444
• Time in Patent Office: 721 Days
• Field of Search: 701/201, 701/209, 701/210, 701/202, 701/211
• US Class Current: 701/201
• CPC Class Codes: G01C 21/3484 Personalized, e.g. from learned user behaviour or user-defined profiles

Abstract

The present invention provides a vehicle navigation system that can customize an optimum route to the driver'"'"'s road preference. The vehicle navigation system includes at least one data table that contains a set of road data. Each set of road data represents characteristics of one road segment, such as a travel time, a length and a type of the road segment. The navigation system also includes at least one coefficient table that contains a number of coefficients. Each coefficient corresponds to one road segment. In a route search operation, an optimum route is calculated so as to optimize road data that have been modified by weighting the road data by the coefficients. The coefficients are changed based on the user'"'"'s personal preference on the corresponding road segments. More specifically, a coefficient is penalized when the corresponding road segment that was part of the optimum route was not traveled. On the other hand, a coefficient is credited when the corresponding road segment that was not part of the optimum route was actually traveled.

Claims

1. A vehicle navigation system that calculates an optimum route between two geographical points designated as a starting point and a destination point, said navigation system comprising:

(a) at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment, and

(c) means for searching said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said navigation system further comprises a history table storing geographical points designated in the past as a starting point or a destination point, and said optimum route is calculated, using both said modified road data and said road data, said modified road data being used to search an area within a certain distance of either or each of two newly designated geographical points when either of the points is already stored in said history table, and said road data being used to search areas other than the area searched with said modified road data.

2. A vehicle navigation system that calculates an optimum route between two geographical points designated as a starting point and a destination point, said navigation system comprising:

(a) at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment, and

(c) means for searching said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient is changed based on user'"'"'s personal preference regarding the corresponding road segment, said coefficient being penalized when the corresponding road segment that was part of said optimum route was not traveled, whereas said coefficient is credited when the corresponding road segment that was not part of said optimum route was actually traveled.

3. A vehicle navigation system according to claim 2, wherein said navigation system further comprises a history table storing geographical points designated in the past as a starting point or a destination point, and said optimum route is calculated, using said modified road data, when either of two newly designated geographical points is already stored in said history table.

4. A vehicle navigation system according to claim 3, wherein said optimum route is calculated, using said road data, if neither of the two geographical points newly designated is not stored in the history table.

5. A vehicle navigation system according to claim 3, wherein said history table is renewed on a regular basis so that geographical points are deleted from said history table if they have not been designated for a certain period of time.

6. A vehicle navigation system according to claim 2, wherein said road data include costs each representing a time to travel the corresponding road segment.

7. A vehicle navigation system according to claim 6, wherein said optimum route consists of road segments along which a sum of the corresponding costs weighted by the corresponding coefficient is the minimum.

8. A vehicle navigation system according to claim 2, wherein said coefficient is penalized or credited along a straight line with an increase in the number of occurrences that said coefficient is changed.

9. A vehicle navigation system according to claim 2, wherein said coefficient is penalized or credited along a curved line with an increase in the number of occurrences that said coefficient is changed.

10. A vehicle navigation system according to claim 2, wherein said coefficient table is personalized to individual drivers, and each driver uses the coefficient table personalized to the driver.

11. A vehicle navigation system that calculates an optimum route between two geographical points designated as a starting point and a destination point, said navigation system comprising:

(a) at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment, and

(c) means for searching said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient table is renewed on a regular basis so that coefficients are changed to an initial value if they have not been changed for a certain period of time.

12. A vehicle navigation system that calculates an optimum route between two geographical points designated as a starting point and a destination point, said navigation system comprising:

(a) at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment;

(b) means for changing said coefficients based on user'"'"'s personal preference regarding the corresponding road segments; and

(c) means for searching said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient is penalized when the corresponding road segment that was part of said optimum route was not traveled, whereas said coefficient is credited when the corresponding road segment that was not part of said optimum route was actually traveled.

13. A vehicle navigation system according to claim 12, wherein said coefficient is penalized or credited along a straight line with an increase in the number of occurrences that said coefficient is changed.

14. A vehicle navigation system according to claim 12, wherein said coefficient is penalized or credited along a curved line with an increase in the number of occurrences that said coefficient is changed.

15. A vehicle navigation system according to claim 12, wherein said coefficient table is personalized to individual users, and each user uses the coefficient table personalized to the user.

16. A vehicle navigation system that calculates an optimum route between two geographical points designated as a starting point and a destination point, said navigation system comprising:

(a) at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment;

(b) means for changing said coefficients based on user'"'"'s personal preference regarding the corresponding road segments; and

(c) means for searching said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient table is renewed on a regular basis so that coefficients are changed to an initial value if they have not been changed for a certain period of time.

17. A method of calculating an optimum route between two geographical points designated as a starting point and a destination point, said method comprising the steps of:

(a) defining at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) defining at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment,

(c) defining a history table storing geographical points designated in the past as a starting point or a destination point, and

(d) calculating said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients when either of two newly designated geographical points is already stored in said history table;

wherein said step (d) uses both said modified road data and said road data, said modified road data being used to search an area within a certain distance of either or each of said two newly designated geographical points when either of the points is already stored in said history table, and said road data being used to search areas other than the area searched with said modified road data.

18. A method of calculating an optimum route between two geographical points designated as a starting point and a destination point, said method comprising the steps of:

(a) defining at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) defining at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment, and

(c) calculating said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient is changed based on user'"'"'s personal preference regarding the corresponding road segment, said coefficient being penalized when the corresponding road segment that was part of said optimum route was not traveled, whereas said coefficient is credited when the corresponding road segment that was not part of said optimum route was actually traveled.

19. A method according to claim 18, further comprising the step of defining a history table storing geographical points designated in the past as a starting point or a destination point, wherein said step (c) uses said modified road data when either of two newly designated geographical points is already stored in said history table.

20. A method according to claim 19, wherein said step (c) uses said road data when neither of the two newly designated geographical points is not stored in the history table.

21. A method according to claim 18, wherein said road data include costs each representing a time travel the corresponding road segment.

22. A method according to claim 21, wherein said optimum route consists of road segments along which a sum of the corresponding costs weighted by the corresponding coefficient is the minimum.

23. A method according to claim 18, wherein said coefficient is penalized or credited along a straight line with an increase in the number of occurrences that said coefficient is changed.

24. A method according to claim 18, wherein said coefficient is penalized or credited along a curved line with an increase in the number of occurrences that said coefficient is changed.

25. A method according to claim 18, wherein said coefficient table is personalized to individual drivers, and each driver uses the coefficient table personalized to the driver.

26. A method of calculating an optimum route between two geographical points designated as a starting point and a destination point, said method comprising the steps of:

(a) defining at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) defining at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment, and

(c) calculating said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients;

wherein said coefficient table is renewed on a regular basis so that coefficients are changed to an initial value if they have not been changed for a certain period of time.

27. A method of calculating an optimum route between two geographical points designated as a starting point and a destination point, said method comprising the steps of:

(a) defining at least one data table containing sets of road data each set representing characteristics of one road segment,

(b) defining at least one coefficient table containing a set of coefficients each coefficient corresponding to one road segment,

(c) defining a history table storing geographical points designated in the past as a starting point or a destination point, and

(d) calculating said optimum route between said two geographical points, using modified road data that are obtained by weighting said road data by said coefficients when either of two newly designated geographical points is already stored in said history table;

wherein said history table is renewed on a regular basis so that geographical points are deleted from said history table if they have not been designated for a certain period of time.