Automatically identifying geographic direction

• US 8,898,034 B2
• Filed: 06/03/2009
• Issued: 11/25/2014
• Est. Priority Date: 06/03/2009
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Huang, Ronald Keryuan, Piemonte, Patrick
• Primary Examiner(s): Breene, John
• Assistant Examiner(s): RIVERA VARGAS, MANUEL A
• Application Number:
  US12/477,865
• Publication Number:
  US 20100312519A1
• Time in Patent Office: 2,001 Days
• Field of Search: 702/150, 701/525
• US Class Current: 702/150
• CPC Class Codes: G01C 17/28 Electromagnetic compasses with north seeking magnetic elements and having electric pick-offs G01C17/26
• CPC Class Codes: G01C 17/38 Testing, calibrating, or compensating of compasses

Abstract

Automatically identifying a geographic direction (e.g., a heading relative to true north) is disclosed. Responsive to a correction trigger event, geographic position data that identifies a geographic position of the device can be obtained. A magnetic declination based on the geographic position data can be obtained. A magnetic heading of the device can be obtained. A geographic direction based on the magnetic heading and the magnetic declination can be identified without user intervention.

Claims

1. A device comprising:

one or more processors; and

memory coupled to the one or more processors and storing instructions which, when executed by the one or more processors, are configured to cause the one or more processors to perform operations comprising;

presenting, on a user interface shown on a display coupled to the device, a first user interface element that provides an option to a user to select one of a magnetic direction or a geographic direction to be shown on the device;

presenting, on the user interface, a second user interface element that is associated with the first user interface element and is configured to allow the user to input a time period at which heading correction is identified;

obtaining periodically, based on user inputs corresponding to the first and second user interface elements, geographic position data that identifies a current geographic position of the device;

examining, using the geographic position data, declination data that is pre-stored in the device;

responsive to examining the declination data, identifying a magnetic declination at the current geographic position of the device;

obtaining a magnetic heading of the device; and

identifying, without user intervention, a geographic direction of the device based on the magnetic heading and the magnetic declination.

2. The device of claim 1, wherein the instructions are configured to cause the one or more processors to perform operations comprising:

presenting, on the display coupled to the device, content associated with one or more landmarks that are located in the identified geographical direction.

3. The device of claim 2, wherein the content comprises one of an audio recording identifying the one or more landmarks located in the identified geographical direction, a video recording identifying the one or more landmarks located in the identified geographical direction, or a graphical image identifying the one or more landmarks located in the identified geographical direction.

4. The device of claim 1, comprising a magnetometer, where the magnetic heading is obtained based on measurements made by the magnetometer.

5. The device of claim 1, where the instructions that cause the one or more processors to perform operations comprising identifying the magnetic declination includes instructions that cause the one or more processors to perform operations comprising:

identifying from the declination data, a magnitude of a first magnetic declination that corresponds to the geographic position.

6. The device of claim 1, where the declination data is stored in the memory.

7. The device of claim 1, where the declination data is represented in a geomagnetic model that is configured to provide magnetic field components used to identify the magnetic declination and the magnetic heading.

8. The device of claim 1, where the instructions are configured to cause the one or more processors to perform operations comprising:

periodically downloading in the device a geomagnetic model from a predetermined network location; and

updating the declination data that is pre-stored in the device using the geomagnetic model that is downloaded from the predetermined network location.

9. The device of claim 1, comprising instructions that cause the one or more processors to perform operations including:

obtaining temporal data that is related to the geographic position data and identifies a time of day at which the temporal data is obtained;

examining the declination data that is pre-stored in the device using the geographic position data and the identified time of day; and

responsive to examining the declination data, determining a magnitude of the magnetic declination that corresponds to the current geographic position and the identified time of day.

10. The device of claim 1, wherein the instructions that are configured to cause the one or more processors to perform operations comprising obtaining geographic position data include instructions that are configured to cause the one or more processors to perform operations comprising:

measuring a speed at which the device is moving;

computing an average speed of the device based on the measured speed;

obtaining a predetermined time period corresponding to the computed average speed; and

identifying the magnetic declination and identifying, without user intervention, the geographic direction, periodically based on the predetermined time period.

11. The device of claim 1, comprising instructions that cause the one or more processors to perform operations comprising:

displaying, on a user interface associated with the device, an indicator identifying the geographic direction, where the indicator is overlaid on a map for marking the current geographic position of the device.

12. A computer-implemented method, comprising:

presenting, on a user interface shown on a display coupled to a device, a first user interface element that provides an option to a user to select one of a magnetic direction or a geographic direction to be shown on the device;

presenting, on the user interface, a second user interface element that is associated with the first user interface element and is configured to allow the user to input a time period at which heading correction is identified;

obtaining periodically, based on user inputs corresponding to the first and second user interface elements, geographic position data that identifies a current geographic position of the device;

examining, using the geographic position data, declination data that is pre-stored in the device;

responsive to examining the declination data, identifying a magnetic declination at the current geographic position of the device;

obtaining a magnetic heading of the device; and

identifying, without user intervention, a geographic direction of the device based on the magnetic heading and the magnetic declination.

13. The method of claim 12, comprising:

presenting, on the device, content associated with one or more landmarks that are located in the identified geographical direction.

14. The method of claim 13, wherein the content comprises one of an audio recording identifying the one or more landmarks located in the identified geographical direction, a video recording identifying the one or more landmarks located in the identified geographical direction, or a graphical image identifying the one or more landmarks located in the identified geographical direction.

15. The method of claim 12, comprising:

presenting an indicator of the geographic direction on a user interface associated with the device, where the indicator is overlaid on a map for marking the current geographic position of the device.

16. The method of claim 12, where the magnetic heading is obtained based on measurements made by one of a compass or a magnetometer.

17. The method of claim 12, where identifying the magnetic declination includes:

identifying from the declination data, a magnitude of a first magnetic declination that corresponds to the geographic position.

18. The method of claim 12, where the declination data is represented in a geomagnetic model that is configured to provide magnetic field components used to identify the magnetic declination and the magnetic heading.

19. The method of claim 12, comprising:

periodically downloading in the device, without user intervention, a geomagnetic model from a predetermined network location; and

updating, without user intervention, the declination data that is pre-stored in the device using the geomagnetic model that is downloaded from the predetermined network location.

20. The method of claim 12, comprising:

obtaining temporal data that is related to the geographic position data and identifies a time of day at which the temporal data is obtained;

examining the declination data that is pre-stored in the device using the geographic position data and the identified time of day; and

responsive to examining the declination data, determining a magnitude of the magnetic declination that corresponds to the current geographic position and the identified time of day.

21. The method of claim 12, wherein obtaining geographic position data comprises:

measuring, a speed at which the device is moving;

computing an average speed of the device using the measured speed;

selecting a predetermined time period corresponding to the computed average speed; and

identifying the magnetic declination and identifying, without user intervention, the geographic direction periodically based on the predetermined time period.