METHODS AND APPARATUS FOR ADJUSTING HEADING DIRECTION IN A NAVIGATION SYSTEM

• US 20140005928A1
• Filed: 06/29/2012
• Published: 01/02/2014
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Peretz, Eyal, Giannetta, Michael J., Zhang, Chi
• Granted Patent: US 9,194,702 B2
• Time in Patent Office: Days
• US Class Current: 701/431
• CPC Class Codes: G01C 17/28 Electromagnetic compasses with north seeking magnetic elements and having electric pick-offs G01C17/26
• CPC Class Codes: G01C 21/08 involving use of the magnetic field of the earth
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 19/52 Determining velocity

Abstract

A mobile device is described. The mobile device includes an electronic compass that generates compass data corresponding to an orientation of the mobile device relative to true north. A global positioning system (GPS) module receives a GPS signal from multiple satellites. The GPS module determines a heading direction of a vehicle transporting the mobile device relative to true north based on the position data when the vehicle is moving above a threshold velocity. A motion sensor generates motion data corresponding to a motion of the mobile device when the mobile device is moved. A processor adjusts the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.

Claims

1. A mobile device comprising:

an electronic compass generating compass data corresponding to an orientation of the mobile device relative to true north;

a global positioning system (GPS) module receiving a GPS signal from a plurality of satellites, the GPS module determining a heading direction of a vehicle transporting the mobile device relative to true north based on the GPS signal when the vehicle is moving above a threshold velocity;

a motion sensor generating motion data corresponding to a motion of the mobile device when the mobile device is moving; and

a processor adjusting the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.

2. The mobile device of claim 1 further comprising a display for displaying a route of the mobile device and a pointer overlaid on the route, the direction of the pointer indicating the heading direction of the vehicle relative to true north.

3. The mobile device of claim 2 wherein the processor periodically adjusts the direction of the pointer in response to the compass data.

4. The mobile device of claim 1 wherein the processor is integrated with the GPS module.

5. The mobile device of claim 1 wherein the GPS module outputs National Marine Electronics Association (NMEA) data.

6. The mobile device of claim 1 wherein the GPS module determines the velocity data by dividing a change in a position of the mobile device by a change in time.

7. The mobile device of claim 1 wherein the motion sensor detects a change in orientation of the mobile device relative to the vehicle that triggers the processor to adjust the heading direction of the vehicle in response to the change in orientation.

8. The mobile device of claim 1 further comprising a user interface for instructing the processor to cease adjusting the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.

9. The mobile device of claim 1 wherein the motion sensor comprises at least one of an accelerometer and a gyroscope.

10. A method of adjusting heading direction in a mobile device comprising:

generating compass data corresponding to an orientation of the mobile device relative to true north;

receiving a global positioning system (GPS) signal from a plurality of satellites;

determining a heading direction of a vehicle transporting the mobile device relative to true north based on the GPS signal when the vehicle is moving above a threshold velocity;

generating motion data corresponding to a motion of the mobile device when the mobile device is moved; and

adjusting the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.

11. The method of claim 10 further comprising displaying a route of the vehicle on a display of the mobile device and a pointer overlaid on the route, the direction of the pointer indicating the heading direction of the vehicle relative to true north.

12. The method of claim 11 further comprising periodically adjusting the direction of the pointer in response to the compass data.

13. The method of claim 10 further comprising outputting National Marine Electronics Association (NMEA) data.

14. A mobile device comprising:

a display for displaying a route of the mobile device, the route including a pointer overlaid on the route, a direction of the pointer indicating the heading direction of a vehicle transporting the mobile device and a position of the pointer indicating a position of the vehicle on the route;

an electronic compass generating compass data corresponding to an orientation of the mobile device relative to true north, the compass data being displayed on the display;

a global positioning system (GPS) module receiving a GPS signal from a plurality of satellites, the GPS module determining a heading direction of a vehicle transporting the mobile device relative to true north based on the GPS signal when the vehicle is moving above a threshold velocity;

a motion sensor generating motion data corresponding to a motion of the mobile device when the mobile device is moving; and

a processor adjusting the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.

15. The mobile device of claim 14 wherein the processor periodically adjusts the direction of the pointer in response to the compass data.

16. The mobile device of claim 14 wherein the processor is integrated with the GPS module.

17. The mobile device of claim 14 wherein the GPS module outputs National Marine Electronics Association (NMEA) data.

18. The mobile device of claim 14 wherein the motion sensor detects a change in orientation of the mobile device relative to the vehicle that triggers the processor to adjust the heading direction of the vehicle in response to the change in orientation.

19. The mobile device of claim 14 wherein the motion sensor comprises at least one of an accelerometer and a gyroscope.

20. The mobile device of claim 14 further comprising a user interface for instructing the processor to cease adjusting the heading direction of the vehicle relative to true north based on the compass data when the vehicle is moving below the threshold velocity.