CONTEXTUAL BASED DETERMINATION OF ACCURACY OF POSITION FIXES

• US 20110025496A1
• Filed: 07/31/2009
• Published: 02/03/2011
• Est. Priority Date: 07/31/2009
• Status: Active Grant

• Current Assignee: Savi Technology Incorporated
• Original Assignee: Deal Magic Inc., Savi Technology Incorporated
• Inventors: Krishna, Narayana C., Cova, Nicholas D.
• Granted Patent: US 8,432,274 B2
• Time in Patent Office: Days
• US Class Current: 340/539.13
• CPC Class Codes: G01S 19/40 Correcting position, velocity or attitude
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence

Abstract

Techniques for contextual based determination of accuracy of position fixes, and modification of the position fixes in accordance with the accuracy are disclosed. In one aspect, a position fix for an asset is received. The first position fix corresponds to a location of an event during shipment of the asset. If it is determined that the position fix is inaccurate, the position fix is modified in accordance with a type of the event.

Claims

1. A computer-implemented method, comprising:

receiving a first position fix for an asset, the first position fix corresponding to a first location of an event during shipment of the asset;

determining if the first position fix is inaccurate; and

if the first position fix is inaccurate, modifying the first position fix in accordance with a type of the first event.

2. The method of claim 1, further comprising:

generating a notification identifying the asset, the event, and the modified first position fix; and

providing the notification to a user.

3. The method of claim 1, wherein determining that the first position fix is inaccurate comprises using one or more parameters for the first position fix.

4. The method of claim 3, wherein the parameters include parameters related to an accuracy of the first position fix.

5. The method of claim 3, wherein the parameters include parameters related to a physical state of the asset.

6. The method of claim 3, wherein the parameters include data from a location determination system other than a system used to determine the first position fix.

7. The method of claim 6, wherein:

the data from the location determination system includes a second position fix from the first location; and

determining that the first position fix is inaccurate includes determining that the first position fix and the second position fix differ by at least a threshold amount.

8. The method of claim 3, wherein the parameters include contextual data for the shipment of the asset.

9. The method of claim 8, wherein:

the parameters include data indicating that the asset has arrived at a known location; and

determining that the first position fix is inaccurate includes determining that the first position fix is not within a geofence for the known location.

10. The method of claim 8, wherein:

the parameters include data indicating that the asset has left a known location; and

determining that the first position fix is inaccurate includes determining that the first position fix is within a geofence for the known location.

11. The method of claim 3, wherein using the parameters to determine that the first position fix is inaccurate includes determining that one or more of the parameters fails to satisfy a respective threshold.

12. The method of claim 11, wherein the respective threshold is determined from a type of the event.

13. The method of claim 1, wherein determining that the first position fix is inaccurate comprises:

comparing the first position fix to a preceding position fix and a succeeding position fix; and

determining that the physical distance between the second position fix and either the preceding position fix or the succeeding position fix exceeds a threshold.

14. The method of claim 13, wherein the threshold is determined from an accuracy factor for a device used to generate the second position fix.

15. The method of claim 13, wherein the threshold is a distance that the asset could have traveled between the position fixes.

16. The method of claim 15, further comprising:

receiving one or more parameters corresponding to the first position fix;

using the parameters to determine a speed at which the asset was moving; and

determining the distance that the asset could have traveled from the speed at which the asset was moving.

17. The method of claim 16, wherein the parameters include accelerometer data for one or more of a preceding position fix, the first position fix, and a subsequent position fix.

18. The method of claim 16, wherein the parameters include velocimeter data for the first position fix.

19. The method of claim 1, wherein modifying the first position fix comprises:

determining that the type of the first event is a process event indicating that a shipping event has occurred;

identifying an updated location, the updated location being a valid location for the shipping event; and

modifying the first position fix to indicate the updated location.

20. The method of claim 19, wherein the shipping event is that the shipment is beginning, and identifying the updated location comprises:

determining whether a valid origin location for the shipment is within a threshold radius of the first position fix; and

identifying the valid origin location as the valid location if the valid origin location is within a threshold radius of the first position fix, and otherwise identifying an origin location associated with a sender of the shipment.

21. The method of claim 20, wherein the shipping event is that the shipment is ending, and identifying the updated location comprises:

determining whether a valid destination location for the shipment is within a threshold radius of the first position fix; and

identifying the valid destination location as the valid location if the valid destination location is within a threshold radius of the first position fix, and otherwise identifying a destination location associated with a receiver of the shipment.

22. The method of claim 1, wherein modifying the first position fix comprises:

determining that the type of the first event is an environmental event indicating that an environmental requirement for the asset has been violated; and

modifying the first position fix to be a last received position fix having an accuracy score that satisfies the threshold value for events having the type environmental event.

23. The method of claim 1, wherein modifying the first position fix comprises:

determining that the type of the first event is a tracking event indicating a periodic position of the asset; and

modifying the first position fix based on one or more other position fixes for the asset.

24. A system, comprising:

a tag configured to perform operations comprising;

receiving position fix data for an asset; and

generating notifications identifying position fixes for events during shipment of the asset;

one or more servers configured to perform operations comprising;

receiving a first position fix for the asset from the tag, the first position fix corresponding to a first location of a first event during shipment of the asset;

determining if the first position fix is inaccurate; and

if the first position fix is inaccurate, modifying the first position fix in accordance with a type of the first event.

25. A system, comprising:

a tag configured to perform operations comprising;

receiving a first position fix for an asset, the first position fix corresponding to a first location of an event during shipment of the asset;

determining if the first position fix is inaccurate;

if the first position fix is inaccurate, modifying the first position fix in accordance with a type of the first event; and

generating an event notification identifying the event and the modified first position fix; and

sending the event notification to a server.