Method of determining routes for use in navigation

• US 8,700,327 B2
• Filed: 04/27/2010
• Issued: 04/15/2014
• Est. Priority Date: 04/27/2010
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Cabral, Cesar
• Primary Examiner(s): Jabr, Fadey
• Assistant Examiner(s): SCHNEIDER, PAULA LYNN
• Application Number:
  US12/768,284
• Publication Number:
  US 20110264366A1
• Time in Patent Office: 1,449 Days
• Field of Search: 701/200, 701/204, 701/400, 701/414, 701/201, 701/410, 701/411, 701/416, 701/533
• US Class Current: 701/533
• 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 1/096822 where the segments of the route are transmitted to the vehicle at different locations and times
• CPC Class Codes: G08G 1/096844 where the complete route is dynamically recomputed based on new data
• CPC Class Codes: G08G 1/096866 where the complete route is shown to the driver

Abstract

A method of determining routes for use in navigation is disclosed. The method includes steps of calculating a current route, calculating an alternative route and comparing the difference in times along each route with a minimum time difference. The minimum time difference is calculated using a dynamic threshold value that varies according to the difference in distances along the current route and the alternative route.

Claims

1. A method of providing navigation information for a motor vehicle including a navigation system having an electronic control unit, comprising the steps of:

retrieving, by the electronic control unit in the navigation system, a current route that is being used to navigate the motor vehicle to a destination;

receiving, by the electronic control unit in the navigation system, a current location for the motor vehicle;

calculating, by the electronic control unit in the navigation system, an alternative route from the current location to the destination, wherein a first travel time between the current location and the destination along the alternative route is estimated to be less than a second travel time between the current location and the destination along the current route;

determining, by the electronic control unit in the navigation system, a first distance corresponding to the alternative route and a second distance corresponding to the distance left to travel on the current route;

calculating, by the electronic control unit in the navigation system, a dynamic threshold value that changes as a function of one or more inputs that change as the motor vehicle travels towards the destination;

wherein all the foregoing steps are executed by the electronic control unit in the navigation system as the motor vehicle is travelling along the current route towards the destination; and

using, by the electronic control unit in the navigation system, the dynamic threshold value, the first distance, the second distance, the first travel time and the second travel time to determine if the alternative route should be displayed for the user.

2. The method according to claim 1, wherein the current location is a GPS location.

3. The method according to claim 1, wherein the dynamic threshold value varies as a function of the distance along the current route and the distance along the alternative route.

4. The method according to claim 3, wherein the dynamic threshold value is calculated using a difference between the first distance and the second distance.

5. The method according to claim 4, wherein the dynamic threshold value increases as the value of the first distance minus the second distance increases.

6. The method according to claim 3, wherein the dynamic threshold value is used to calculate a minimum time difference and wherein the navigation system compares the difference between the second travel time and the first travel time to the minimum time difference.

7. A method of providing navigation information for a motor vehicle including a navigation system having an electronic control unit, comprising the steps of:

retrieving, by the electronic control unit in the navigation system, a current route that is being used to navigate the motor vehicle to a destination;

receiving, by the electronic control unit in the navigation system, a current location for the motor vehicle;

calculating, by the electronic control unit in the navigation system, an alternative route from the current location to the destination, wherein a first travel time between the current location and the destination along the alternative route is estimated to be less than a second travel time between the current location and the destination along the current route;

determining, by the electronic control unit in the navigation system, a first distance corresponding to the alternative route and a second distance corresponding to the distance left to travel on the current route;

calculating, by the electronic control unit in the navigation system, a minimum time difference;

submitting, by the electronic control unit in the navigation system, the alternative route to be displayed for a user when the value of the second travel time minus the first travel time is greater than the minimum time difference;

calculating, by the electronic control unit in the navigation system, a dynamic threshold value that changes as a function of one or more inputs that change as the motor vehicle travels towards the destination;

wherein the minimum time difference is calculated from at least the first distance, the second distance and the dynamic threshold value;

wherein all the foregoing steps are executed by the electronic control unit in the navigation system as the motor vehicle is travelling along the current route towards the destination;

preventing, by the electronic control unit in the navigation system, the alternative route from being displayed for the user when the value of the second travel time minus the first travel time is less than or equal to the minimum time difference.

8. The method according to claim 7, wherein the minimum time difference increases as the difference between the first distance and the second distance increases.

9. The method according to claim 7, wherein the minimum time difference increases as the value of the first distance minus the second distance increases.

10. The method according to claim 7, wherein the minimum time difference is equal to the dynamic threshold value multiplied by the second travel time.

11. The method according to claim 10, wherein the dynamic threshold value is calculated as a function of the difference between the first distance and the second distance.

12. The method according to claim 11, wherein the dynamic threshold value increases as the value of the first distance minus the second distance increases.

13. The method according to claim 12, wherein the dynamic threshold value approaches a maximum value asymptotically as a function of the difference between the first distance and the second distance.

14. A method of providing navigation information for a motor vehicle including a navigation system having an electronic control unit, comprising the steps of:

retrieving, by the electronic control unit in the navigation system, a current route that is being used to navigate the motor vehicle to a destination;

receiving, by the electronic control unit in the navigation system, a current location for the motor vehicle;

calculating, by the electronic control unit in the navigation system, an alternative route from the current location to the destination, wherein a first travel time between the current location and the destination along the alternative route is estimated to be less than a second travel time between the current location and the destination along the current route;

determining, by the electronic control unit in the navigation system, a first distance corresponding to the alternative route and a second distance corresponding to the distance left to travel on the current route;

calculating, by the electronic control unit in the navigation system, a dynamic threshold value that changes as a function of one or more inputs that change as the motor vehicle travels towards the destination, wherein the dynamic threshold value approaches a maximum value asymptotically as a function of the difference between the first distance and the second distance;

setting, by the electronic control unit in the navigation system, a minimum time difference equal to the dynamic threshold value multiplied by the second travel time;

wherein all the foregoing steps are executed by the electronic control unit in the navigation system as the motor vehicle is travelling along the current route towards the destination; and

comparing, by the electronic control unit in the navigation system, the value of the second travel time minus the first travel time with the minimum time difference to determine if the alternative route should be displayed for a user.

15. The method according to claim 14, wherein the calculation of the dynamic threshold value incorporates an arctangent function;

and wherein the method further includes a step of;

submitting, by the electronic control unit in the navigation system, the alternative route to be displayed for a user when the value of the second travel time minus the first travel time is greater than the minimum time difference.

16. The method according to claim 15, wherein the method further includes the step of:

preventing, by the electronic control unit in the navigation system, the alternative route from being displayed for the user when the value of the second travel time minus the first travel time is less than or equal to the minimum time difference.

17. The method according to claim 14, wherein the dynamic threshold value increases as the value of the first distance minus the second distance increases.

18. The method according to claim 14, wherein the dynamic threshold value decreases as the value of the first distance minus the second distance decreases.

19. The method according to claim 14, wherein the dynamic threshold value increases as the absolute value of the first distance minus the second distance increases.

20. The method according to claim 14, wherein a probability that the alternative route is displayed decreases as the value of the first distance minus the second distance increases.