SYSTEM AND METHOD FOR IMPROVING ORIENTATION DATA

• US 20130110439A1
• Filed: 10/12/2012
• Published: 05/02/2013
• Est. Priority Date: 11/01/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: KULIK, Victor, AHUJA, Disha, PUIG, Carlos M.
• Granted Patent: US 9,785,254 B2
• Time in Patent Office: Days
• US Class Current: 702/94
• CPC Class Codes: G01B 21/22 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01C 17/38 Testing, calibrating, or compensating of compasses
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G06F 15/00 Digital computers in general details G06F1/00 – G06F13/00; Data processing equipment in general
• CPC Class Codes: G06F 2200/1637 Sensing arrangement for detection of housing movement or orientation, e.g. for controlling scrolling or cursor movement on the display of an handheld computer
• CPC Class Codes: G06F 3/0304 Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry

Abstract

Aspects of the disclosure relate to computing technologies. In particular, aspects of the disclosure relate to mobile computing device technologies, such as systems, methods, apparatuses, and computer-readable media for improving orientation data. In some embodiments, a magnetic vector filter receives magnetometer data from a magnetometer and gyroscope data from a gyroscope and determines the magnetic vector using the magnetometer data and the gyroscope data in the magnetic vector filter. In other embodiments, a gravity vector filter receives accelerometer data and gyroscope data and determines the gravity vector using the accelerometer data and the gyroscope data in the gravity vector filter.

Claims

1. A method to obtain information for use with an orientation determination for a computing device, the method comprising:

receiving magnetometer data at a magnetic vector filter, wherein the magnetometer data comprises sensor output from a magnetometer;

receiving gyroscope data at the magnetic vector filter, wherein the gyroscope data comprises sensor output from a gyroscope; and

determining a magnetic vector by using the magnetometer data and the gyroscope data in the magnetic vector filter, the magnetic vector filter being capable of determining the magnetic vector independent of accelerometer data for use with the orientation determination.

2. The method of claim 1, further comprising:

receiving the accelerometer data at a gravity vector filter, wherein the accelerometer data comprises sensor output from an accelerometer;

receiving the gyroscope data at the gravity vector filter; and

determining a gravity vector by using the accelerometer data and the gyroscope data in the gravity vector filter, wherein the gravity vector is used for determining the orientation of the computing device.

3. The method of claim 2, wherein at least one of the gravity vector filter and the magnetic vector filter use an adaptive filter, and at least one filter parameter of the adaptive filter is dynamically adjustable.

4. The method of claim 3, wherein the at least one filter parameter is associated with the gravity vector filter, the at least one filter parameter comprising one or more of a signal noise, a measurement error, a sensor calibration error or a linear acceleration.

5. The method of claim 3, wherein the at least one filter parameter is associated with the magnetic vector filter, the at least one filter parameter comprising one or more of sensor calibration error or a magnetic transient field.

6. The method of claim 3, wherein the adaptive filter comprises a Kalman filter.

7. The method of claim 2, wherein the magnetic vector filter is separate from the gravity vector filter.

8. The method of claim 2, further comprising an expanded adaptive filter, wherein the expanded adaptive filter receives as inputs computed coordinates of the gravity vector for the computing device along with the gyroscope data and the accelerometer data.

9. The method of claim 1, further comprising determining based on the magnetometer data and the gyroscope data, whether a detected change in a magnetic field in the magnetic vector filter is a magnetic anomaly.

10. The method of claim 9, further comprising:

in response to determining that the gyroscope did not measure a change during a period of time in which the change in the magnetic field was detected, determining that the detected change in the magnetic field is the magnetic anomaly.

11. The method of claim 9,

wherein the detected change in the magnetic field is determined not to be the magnetic anomaly when the received sensor output from the gyroscope correlates to a detected change in the magnetic field;

and

wherein the detected change in the magnetic field is determined to be the magnetic anomaly when the received sensor output from the gyroscope does not correlate to the detected change in the magnetic field.

12. The method of claim 9, further comprising:

in response to determining that the detected change in the magnetic field is the magnetic anomaly, disregarding filter input received from the magnetometer corresponding to the detected change in the magnetic field.

13. The method of claim 9, further comprising:

in response to determining that the detected change in the magnetic field is the magnetic anomaly, increasing a window size associated with the magnetic vector filter.

14. The method of claim 9, wherein determining the detected change is a magnetic anomaly comprises comparing the magnetometer data to a threshold.

15. The method of claim 14, further comprising calculating the threshold based at least in part on the gyroscope data.

16. A computing device for determining orientation, comprising:

a receiver coupled to a magnetic vector filter and configured to;

receiving magnetometer data at the magnetic vector filter, wherein the magnetometer data comprises sensor output from a magnetometer;

receiving gyroscope data at the magnetic vector filter, wherein the gyroscope data comprises sensor output from a gyroscope; and

the magnetic vector filter configured to;

determine a magnetic vector by using the magnetometer data and the gyroscope data in the magnetic vector filter, the magnetic vector filter being capable of determining the magnetic vector independent of accelerometer data for use with the orientation determination.

17. The computing device of claim 16, further comprising:

a receiver coupled to a gravity vector filter and configured to;

receive the accelerometer data at the gravity vector filter, wherein the accelerometer data comprises sensor output from an accelerometer;

receive the gyroscope data at the gravity vector filter; and

the gravity vector filter configured to;

determine a gravity vector by using the accelerometer data and the gyroscope data in the gravity vector filter, wherein the gravity vector is used for determining the orientation of the computing device.

18. The computing device of claim 17, wherein at least one of the gravity vector filter and the magnetic vector filter use an adaptive filter, and at least one filter parameter of the adaptive filter is dynamically adjustable.

19. The computing device of claim 18, wherein the at least one filter parameter is associated with the gravity vector filter, the at least one filter parameter comprising one or more of a signal noise, a measurement error, a sensor calibration error or a linear acceleration.

20. The computing device of claim 18, wherein the at least one filter parameter is associated with the magnetic vector filter, the at least one filter parameter comprising one or more of sensor calibration error or a magnetic transient field.

21. The computing device of claim 18, wherein the adaptive filter comprises a Kalman filter.

22. The computing device of claim 17, wherein the magnetic vector filter is separate from the gravity vector filter.

23. The computing device of claim 17, further comprising an expanded adaptive filter, wherein the expanded adaptive filter receives as inputs computed coordinates of the gravity vector for the computing device along with the gyroscope data and the accelerometer data.

24. The computing device of claim 16, the magnetic vector filter further configured to determine based on the magnetometer data and the gyroscope data, whether a detected change in a magnetic field in the magnetic vector filter is a magnetic anomaly.

25. The computing device of claim 24, the magnetic vector filter further configured to determine that the detected change in the magnetic field is the magnetic anomaly, in response to determining that the gyroscope did not measure a change during a period of time in which the change in the magnetic field was detected.

26. The computing device of claim 24,

wherein the detected change in the magnetic field is determined by the magnetic vector filter not to be the magnetic anomaly when the received sensor output from the gyroscope correlates to a detected change in the magnetic field;

and

wherein the detected change in the magnetic field is determined by the magnetic vector to be the magnetic anomaly when the received sensor output from the gyroscope does not correlate to the detected change in the magnetic field.

27. The computing device of claim 24, the magnetic vector filter further configured to disregard filter input received from the magnetometer corresponding to the detected change in the magnetic field, in response to determining that the detected change in the magnetic field is the magnetic anomaly.

28. The computing device of claim 24, further comprising a processor configured to increase a window size associated with the magnetic vector filter in response to the magnetic vector filter determining the detected change in the magnetic field is the magnetic anomaly.

29. The computing device of claim 24, wherein the magnetic vector filter is configured to determine the detected change is a magnetic anomaly by comparing the magnetometer data to a threshold.

30. The computing device of claim 29, wherein the magnetic vector filter is configured to calculate the threshold based at least in part on the gyroscope data.

31. A non-transitory computer readable storage medium, wherein the non-transitory computer readable storage medium comprises instructions executable by a processor, the instructions comprising instructions to:

receive magnetometer data at a magnetic vector filter, wherein the magnetometer data comprises sensor output from a magnetometer;

receive gyroscope data at the magnetic vector filter, wherein the gyroscope data comprises sensor output from a gyroscope; and

determine a magnetic vector by using the magnetometer data and the gyroscope data in the magnetic vector filter, the magnetic vector filter being capable of determining the magnetic vector independent of accelerometer data for use with an orientation determination.

32. An apparatus, comprising:

means for receiving magnetometer data at a magnetic vector filter, wherein the magnetometer data comprises sensor output from a magnetometer;

means for receiving gyroscope data at the magnetic vector filter, wherein the gyroscope data comprises sensor output from a gyroscope; and

means for determining a magnetic vector by using the magnetometer data and the gyroscope data in the magnetic vector filter, the magnetic vector filter being capable of determining the magnetic vector independent of accelerometer data for use with an orientation determination.

33. The apparatus of claim 32, further comprising:

means for receiving the accelerometer data at a gravity vector filter, wherein the accelerometer data comprises sensor output from an accelerometer;

means for receiving the gyroscope data at the gravity vector filter; and

means for determining a gravity vector by using the accelerometer data and the gyroscope data in the gravity vector filter, wherein the gravity vector is used for determining the orientation.

34. The apparatus of claim 33, wherein at least one of the gravity vector filter and the magnetic vector filter use an adaptive filter, and at least one filter parameter of the adaptive filter is dynamically adjustable.

35. The apparatus of claim 32, further comprising a means for determining based on the magnetometer data and the gyroscope data, whether a detected change in a magnetic field in the magnetic vector filter is a magnetic anomaly;

wherein the detected change in the magnetic field is determined not to be the magnetic anomaly when the received sensor output from the gyroscope correlates to a detected change in the magnetic field; and

wherein the detected change in the magnetic field is determined to be the magnetic anomaly when the received sensor output from the gyroscope does not correlate to the detected change in the magnetic field.

36. The apparatus of claim 35, further comprising:

means for disregarding filter input received from the magnetometer corresponding to the detected change in the magnetic field or means for increasing a window size associated with the magnetic vector filter, in response to determining that the detected change in the magnetic field is the magnetic anomaly.