Power efficient way of operating motion sensors

• US 8,886,980 B2
• Filed: 03/28/2011
• Issued: 11/11/2014
• Est. Priority Date: 03/29/2010
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Kulik, Victor
• Primary Examiner(s): AUVE, GLENN ALLEN
• Application Number:
  US13/073,621
• Publication Number:
  US 20110239026A1
• Time in Patent Office: 1,324 Days
• Field of Search: 713/320, 713/323, 713/324, 702/141, 702/150, 702/151, 341/20
• US Class Current: 713/323
• CPC Class Codes: G01C 19/00 Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system

Abstract

Systems and methods are described for operating motion sensors in a power-efficient manner. An example technique described herein includes obtaining, at a motion sensor, first indications of sensed motion of a device associated with the motion sensor; integrating, at the motion sensor, the first indications of the sensed motion to obtain integrated motion information; generating, at the motion sensor, second indications of the integrated motion information; and sampling, at a processor disparate from the motion sensor, selective ones of the second indications. Another example technique includes obtaining a first indication of a motion state anomaly associated with motion of a mobile device and causing a gyroscope associated with the mobile device to transition between a first operating mode and a second operating mode in response to the first indication, where the first operating mode is a reduced-power mode compared to the second operating mode.

Claims

1. A mobile device comprising:

a processor; and

a motion sensor communicatively coupled to the processor and including;

a motion detection device configured to sense motion of the mobile device and to provide first indications of the motion of the mobile device; and

a processing device communicatively coupled to the motion detection device and configured to receive the first indications, to generate integrated information by integrating the first indications, and to provide second indications indicative of the integrated information;

wherein the processor is configured to obtain selective ones of the second indications;

wherein the processing device of the motion sensor is configured to receive the first indications and to integrate the first indications at a first rate, and the processor is configured to obtain selective ones of the second indications at a second rate that is lower than the first rate.

2. The mobile device of claim 1 wherein the motion sensor is a gyroscope, the first indications are indications of turn rate, and the second indications are indications of turn angle.

3. The mobile device of claim 1 wherein the motion sensor is an accelerometer, the first indications are indications of acceleration, and the second indications are indications of velocity.

4. The mobile device of claim 1 wherein the motion sensor is configured to integrate the motion of the mobile device in accordance with user settings received from a user of the mobile device.

5. A mobile device comprising:

a processor;

a gyroscope communicatively coupled to the processor and configured to sense turn rate of the mobile device; and

a detector communicatively coupled to the processor and the gyroscope and configured to provide a first indication of a motion state anomaly associated with motion of the mobile device;

wherein the processor is configured to cause the gyroscope to transition between a first mode and a second mode in response to the first indication, the first mode being a reduced-power mode compared to the second mode;

wherein the processor is configured to use at least one of the first indication or a second indication associated with sensed acceleration of the mobile device to determine mobile device turn angle while the gyroscope transitions from the first mode to the second mode.

6. The mobile device of claim 5 further comprising an accelerometer communicatively coupled to the processor and configured to provide the second indication, wherein the processor is configured to use the second indication to determine the mobile device turn angle while the gyroscope transitions from the first mode to the second mode.

7. The mobile device of claim 5 wherein the detector comprises a magnetometer, the motion state anomaly is a magnetic anomaly causing magnetometer performance degradation in the mobile device, and the processor is configured to analyze data obtained from the magnetometer to identify the magnetic anomaly.

8. The mobile device of claim 7 wherein the detector is configured to provide a third indication upon identification of the magnetic anomaly, and the processor is configured to cause the gyroscope to transition from the first mode to the second mode in response to the third indication.

9. The mobile device of claim 5 wherein the detector is configured to provide the first indication upon determining that the mobile device is not rotating, and the processor is configured to cause the gyroscope to transition from the second mode to the first mode in response to the first indication.

10. The mobile device of claim 5 further comprising a sensor configured to provide sensed information related to the mobile device, wherein the processor is communicatively coupled to the sensor and configured to emulate output information of the gyroscope using the sensed information while the gyroscope is transitioning from the first mode to the second mode.

11. The mobile device of claim 10 wherein the sensor is at least one of an accelerometer or a magnetometer.

12. The mobile device of claim 5 wherein the second mode is a fully-powered mode and wherein the gyroscope is configured to perform fewer functions when in the first mode than when the gyroscope is in the second mode.

13. A method of operating a motion sensor, the method comprising:

obtaining, at the motion sensor, first indications of sensed motion of a device associated with the motion sensor;

integrating, at the motion sensor, the first indications of the sensed motion to obtain integrated motion information;

generating, at the motion sensor, second indications of the integrated motion information; and

sampling, at a processor disparate from the motion sensor, selective ones of the second indications;

wherein the generating comprises generating the second indications at a first rate and the sampling comprises sampling selective ones of the second indications at a second rate that is slower than the first rate.

14. The method of claim 13 wherein the motion sensor is a gyroscope, the first indications are indications of turn rate, and the second indications are indications of turn angle.

15. The method of claim 13 wherein the motion sensor is an accelerometer, the first indications are indications of acceleration, and the second indications are indications of velocity.

16. The method of claim 13 wherein the integrating comprises integrating the first indications based on user-provided settings.

17. A method of operating a motion sensor, the method comprising:

obtaining a first indication of a motion state anomaly associated with motion of a mobile device;

causing a gyroscope associated with the mobile device to transition between a first operating mode and a second operating mode in response to the first indication; and

determining turn angle of the mobile device while the gyroscope transitions from the first operating mode to the second operating mode based on at least one of the first indication or a second indication associated with sensed acceleration of the mobile device;

wherein the first operating mode is a reduced-power mode compared to the second operating mode.

18. The method of claim 17 wherein the obtaining comprises obtaining a third indication upon determining that the mobile device is not rotating, and the causing comprises causing the gyroscope to transition from the second operating mode to the first operating mode in response to the third indication.

19. The method of claim 17 wherein the obtaining comprises obtaining the first indication upon detecting a magnetic anomaly causing magnetometer performance degradation in the mobile device, and the causing comprises causing the gyroscope to transition from the first operating mode to the second operating mode in response to the first indication.

20. A mobile device comprising:

a processor; and

a motion sensor communicatively coupled to the processor and including;

detection means for sensing motion of the mobile device and generating first information relating to the motion of the mobile device; and

processing means, communicatively coupled to the detection means, for integrating the first information to generate second information indicative of a result of integrating the first information;

wherein the processor is configured to obtain selective samples of the second information;

wherein the processing means is configured to generate the second information at a first rate and the processor is configured to obtain selective samples of the second information at a second rate that is lower than the first rate.

21. The mobile device of claim 20 wherein the first information relates to turn rate of the mobile device and the second information relates to turn angle of the mobile device.

22. The mobile device of claim 20 wherein the first information relates to acceleration of the mobile device and the second information relates to velocity of the mobile device.

23. The mobile device of claim 20 further comprising interface means, communicatively coupled to the processing means, for obtaining user settings from a user of the mobile device, wherein the processing means is configured to integrate the first information in accordance with the user settings.

24. A mobile device comprising:

a processor;

a gyroscope communicatively coupled to the processor and configured to sense turn rate of the mobile device; and

monitor means, communicatively coupled to the processor and the gyroscope, for generating first information relating to a motion state anomaly associated with motion of the mobile device;

wherein the processor is configured to cause the gyroscope to transition between an inactive mode and an active mode in response to the first information;

wherein the processor is further configured to utilize at least one of the first information or second information associated with acceleration of the mobile device to determine turn angle of the mobile device while the gyroscope is operating in the inactive mode or transitioning from the inactive mode to the active mode.

25. The mobile device of claim 24 wherein the monitor means is configured to provide third information upon determining that the mobile device is not rotating, and the processor is configured to cause the gyroscope to transition from the active mode to the inactive mode in response to the third information.

26. The mobile device of claim 24 wherein the monitor means is configured to provide the first information upon detecting a magnetic anomaly causing magnetometer performance degradation in the mobile device, and the processor is configured to cause the gyroscope to transition from the inactive mode to the active mode in response to the first information.

27. A computer program product residing on a non-transitory processor-readable medium and comprising processor-readable instructions configured to cause a processor to:

obtain first indications of sensed motion of a device corresponding to an associated motion sensor;

integrate the first indications to obtain integrated motion information;

generate second indications of the integrated motion information; and

provide, to a disparate processing unit, selective ones of the second indications;

wherein the first indications are integrated at a first rate and the selective ones of the second indications are provided to the disparate processing unit at a second rate that is slower than the first rate.

28. The computer program product of claim 27 wherein the first indications are indications of turn rate and the second indications are indications of turn angle.

29. The computer program product of claim 27 wherein the first indications are indications of acceleration and the second indications are indications of velocity.

30. A computer program product residing on a non-transitory processor-readable medium and comprising processor-readable instructions configured to cause a processor to:

obtain a first indication of a motion state anomaly associated with motion of a mobile device;

instruct transition of a gyroscope associated with the mobile device between a first mode and a second mode in response to the first indication; and

determine turn angle of the mobile device while the gyroscope transitions from the first mode to the second mode based on at least one of the first indication or a second indication associated with sensed acceleration of the mobile device;

wherein the first mode is a reduced-power mode compared to the second mode.

31. The computer program product of claim 30 wherein the processor-readable instructions are further configured to cause the processor to obtain a third indication upon determining that the mobile device is not rotating, and the processor-readable instructions configured to cause a processor to instruct transition of the gyroscope comprise processor-readable instructions configured to cause the processor to instruct transition of the gyroscope from the second mode to the first mode in response to the third indication.

32. The computer program product of claim 30 wherein the processor-readable instructions configured to cause a processor to obtain the first indication comprise processor-readable instructions configured to cause the processor to obtain the first indication upon detecting a magnetic anomaly causing magnetometer performance degradation in the mobile device, and the processor-readable instructions configured to cause a processor to instruct transition of the gyroscope comprise processor-readable instructions configured to cause the processor to instruct transition of the gyroscope from the first mode to the second mode in response to the first indication.