NAVIGATION SYSTEM IMPLEMENTING DYNAMIC ROUTE CORRECTION

• US 20090171577A1
• Filed: 12/31/2008
• Published: 07/02/2009
• Est. Priority Date: 12/31/2007
• Status: Active Grant

• Current Assignee: Smith Micro Software Incorporated
• Original Assignee: Wavemarket Incorporated (Gen Digital Inc.)
• Inventors: Hotes, Scott A., Fromm, Richard, Myers, Jesse, Roumeliotis, Tasso, Augst, Joseph
• Granted Patent: US 8,229,669 B2
• Time in Patent Office: Days
• US Class Current: 701/209
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• 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

Abstract

A computer-implemented navigation method for implementation during a navigation routine for directing a user is provided. The navigation method comprises generating a navigation route. GPS signals are received and position fixes are derived from the GPS signals. The position fixes are stored and compared with the navigation route. A threshold value is determined based on the comparison of the position fixes with the navigation route. An updated navigation route is generated based on the plurality of position fixes distanced from the navigation route a distance greater than the threshold value and an updated navigation route is not generating based on the plurality of position fixes distanced from the navigation route a distance not greater than the threshold value. A mobile device for performing a navigation procedure is also provided.

Claims

1. A computer-implemented navigation method for implementation during a navigation routine to direct a user, the navigation method comprising:

generating a navigation route;

receiving a plurality of GPS signals and deriving a plurality of position fixes from the plurality of GPS signals;

storing the plurality of position fixes;

comparing the plurality of position fixes with the navigation route;

determining at least one threshold value based on the comparison of the plurality of position fixes with the navigation route; and

at least one of generating an updated navigation route based on at least one of the plurality of position fixes being distanced from the navigation route a distance greater than the threshold value and not generating an updated navigation route based on the plurality of position fixes not being distanced from the navigation route a distance greater than the threshold value.

2. The computer-implemented method of claim 1, further comprising:

determining a distance from each of the plurality of position fixes to the navigation route; and

deriving the threshold value from the determination of the distances from the each of the plurality of position fixes to the navigation route.

3. The computer-implemented method of claim 1, further comprising:

determining a shortest distance from each of the plurality of position fixes to the navigation route; and

deriving the threshold value from the determination of the shortest distances.

4. The computer-implemented method of claim 3, further comprising deriving the threshold value as a factor of the standard deviation of the shortest distances from the each of the plurality of position fixes to the navigation route.

5. The computer-implemented method of claim 1, further comprising:

determining a shortest distance from each of the plurality of position fixes to the navigation route;

determining a statistical variance from the shortest distances; and

deriving the threshold value from the statistical variance.

6. The computer-implemented method of claim 1, further comprising:

receiving the plurality of GPS signals and deriving the plurality of position fixes at least one of continuously and at predetermined intervals; and

determining the threshold value based on the comparison of the plurality of position fixes with the navigation route at least one of continuously and at predetermined intervals.

7. The computer-implemented method of claim 6, further comprising determining the threshold value upon each new derivation of a position fix.

8. The computer-implemented method of claim 6, further comprising determining the threshold value based on the comparison of a predetermined number of the most recent of the plurality of position fixes with the navigation route.

9. The computer-implemented method of claim 1, further comprising determining the threshold value based on the comparison of the plurality of position fixes with the navigation route at least one of continuously and at predetermined intervals, wherein a predetermined number of the most recent position fixes are weighted greater than earlier position fixes in determining the threshold value.

10. The computer-implemented method of claim 1, further comprising determining the threshold value based on position fixes obtained during a prior navigation routine.

11. The computer-implemented method of claim 1, further comprising determining the threshold value based on position fixes obtained during a prior navigation routine of another user.

12. The computer-implemented method of claim 1, further comprising generating the updated navigation route based on at least one of the most recent plurality of position fixes distanced from the navigation route a distance greater than the threshold value.

13. The computer-implemented method of claim 1, further comprising generating the updated navigation route based on at least two consecutive ones of the most recent plurality of position fixes distanced from the navigation route a distance greater than the threshold value.

14. A mobile device including at least one memory comprising instructions operable to enable the mobile device to perform a procedure comprising:

generating a navigation route over a mapped area comprising a plurality of navigable paths;

receiving a plurality of GPS signals and deriving a plurality of position fixes from the plurality of GPS signals;

storing the plurality of position fixes;

comparing the plurality of position fixes with the navigation route;

determining a threshold value based on the comparison of the plurality of position fixes with the navigation route; and

generating an updated navigation route if at least one of the plurality of position fixes is distanced from the navigation route a distance greater than the threshold value.

15. The computer-implemented method of claim 14, wherein the at least one memory is further enabled to perform a procedure comprising generating the updated navigation route if at least three consecutive ones of the most recent plurality of position fixes are distanced from the navigation route a distance greater than the threshold value on one side of the navigation route.

16. The computer-implemented method of claim 14, wherein the at least one memory is further enabled to perform a procedure comprising generating the updated navigation route if the at least one of the plurality of position fixes is distanced from the navigation route a distance greater than the threshold value and if the at least one of the plurality of position fixes is within a predetermined distance of a navigable path on which the navigation route is not generated.