Methods and apparatus for detecting, measuring, and mitigating effects of moving an inertial navigation device's cradle

• US 9,151,613 B2
• Filed: 08/12/2011
• Issued: 10/06/2015
• Est. Priority Date: 08/12/2011
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Czompo, Joseph, Lee, Jong Bin D.
• Primary Examiner(s): Dager, Jonathan M
• Application Number:
  US13/209,240
• Publication Number:
  US 20130041585A1
• Time in Patent Office: 1,516 Days
• Field of Search: 701/505
• US Class Current: 1/1
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems

Abstract

Methods and apparatus for detecting, measuring, and/or mitigating effects of moving an inertial navigation device'"'"'s cradle are provided. In an example, provided are methods and apparatus to mitigate cradle rotation-induced inertial navigation errors. In an example, a method for mitigating an inertial navigation error includes receiving inertial sensor data and processing the inertial sensor data with a first navigation algorithm having a non-holonomic constraint (NHC). A second navigation algorithm, lacking a NHC, also processes the inertial sensor data simultaneously with the first algorithm. A cradle rotation is detected by the second navigation algorithm. A first navigation algorithm result, produced from the inertial sensor data generated during the cradle rotation, is discarded. The first algorithm can be computationally realigned, based on a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

Claims

1. A method for mitigating an inertial navigation error, comprising:

receiving inertial sensor data;

processing the inertial sensor data with a first navigation algorithm having a non-holonomic constraint (NHC);

processing the inertial sensor data with a second navigation algorithm lacking a NHC,

wherein the first and second navigation algorithms are executed simultaneously;

detecting a cradle rotation with the second navigation algorithm; and

discarding a first navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

2. The method of claim 1, further comprising outputting a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

3. The method of claim 1, further comprising computationally realigning the first algorithm based on a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

4. The method of claim 3, wherein the realigning includes realigning the first algorithm in one step after the cradle rotation is completed.

5. The method of claim 1, wherein the inertial sensor data is gyroscope output data.

6. The method of claim 1, wherein the inertial sensor data is accelerometer output data.

7. An apparatus configured to mitigate an inertial navigation error, comprising:

means for receiving inertial sensor data;

means for processing the inertial sensor data with a first navigation algorithm having a non-holonomic constraint (NHC);

means for processing the inertial sensor data with a second navigation algorithm lacking a NHC,

wherein the first and second navigation algorithms are executed simultaneously;

means for detecting a cradle rotation with the second navigation algorithm; and

means for discarding a first navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

8. The apparatus of claim 7, further comprising means for outputting a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

9. The apparatus of claim 7, further comprising means for computationally realigning the first algorithm based on a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

10. The apparatus of claim 9, wherein the means for computationally realigning includes means for realigning the first algorithm in one step after the cradle rotation is completed.

11. The apparatus of claim 7, wherein the inertial sensor data is gyroscope output data.

12. The apparatus of claim 7, wherein the inertial sensor data is accelerometer output data.

13. The apparatus of claim 7, wherein at least a part of the apparatus is integrated on a semiconductor die.

14. The apparatus of claim 7, further comprising at least one of a mobile device, a navigation device, communications device, personal digital assistant (PDA), and a computer, into which the apparatus is integrated.

15. An apparatus configured to mitigate an inertial navigation error, comprising a processor configured to:

receive inertial sensor data;

process the inertial sensor data with a first navigation algorithm having a non-holonomic constraint (NHC);

process the inertial sensor data with a second navigation algorithm lacking a NHC,

wherein the first and second navigation algorithms are executed simultaneously;

detect a cradle rotation with the second navigation algorithm; and

discard a first navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

16. The apparatus of claim 15, wherein the processor is further configured to output a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

17. The apparatus of claim 15, wherein the processor is further configured to computationally realign the first algorithm based on a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

18. The apparatus of claim 17, wherein the processor is further configured to computationally realign the first algorithm in one step after the cradle rotation is completed.

19. The apparatus of claim 15, wherein the inertial sensor data is gyroscope output data.

20. The apparatus of claim 15, wherein the inertial sensor data is accelerometer output data.

21. The apparatus of claim 15, wherein at least a part of the processor is integrated on a semiconductor die.

22. The apparatus of claim 15, further comprising at least one of a mobile device, a navigation device, communications device, personal digital assistant (PDA), and a computer, with which the processor is integrated.

23. A non-transitory computer-readable medium, comprising instructions stored thereon that, if executed by a processor, cause the processor to execute a method comprising:

receiving inertial sensor data;

processing the inertial sensor data with a first navigation algorithm having a non-holonomic constraint (NHC);

processing the inertial sensor data with a second navigation algorithm lacking a NHC,

wherein the first and second navigation algorithms are executed simultaneously;

detecting a cradle rotation with the second navigation algorithm; and

discarding a first navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

24. The non-transitory computer-readable medium of claim 23, wherein the method further comprises outputting a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

25. The non-transitory computer-readable medium of claim 23, wherein the method further comprises computationally realigning the first algorithm based on a second navigation algorithm result produced from the inertial sensor data generated during the cradle rotation.

26. The non-transitory computer-readable medium of claim 25, wherein the computational realigning includes realigning the first algorithm in one step after the cradle rotation is completed.

27. The non-transitory computer-readable medium of claim 23, wherein the inertial sensor data is gyroscope output data.

28. The non-transitory computer-readable medium of claim 23, wherein the inertial sensor data is accelerometer output data.

29. The non-transitory computer-readable medium of claim 23, wherein the non-transitory computer-readable medium is integrated with at least one of a mobile device, a navigation device, communications device, personal digital assistant (PDA), and a computer.