Human activity monitoring device

• US 8,712,723 B1
• Filed: 01/31/2011
• Issued: 04/29/2014
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Uniloc 2017 LLC (SoftBank Group Corp.)
• Original Assignee: DP Technologies, Inc.
• Inventors: Vogel, David, Kahn, Philippe, Kinsolving, Arthur, Christensen, Mark Andrew, Lee, Brian Y.
• Primary Examiner(s): COSIMANO, EDWARD R
• Application Number:
  US13/018,321
• Time in Patent Office: 1,184 Days
• Field of Search: 337/00, 337/01, 73/10.1, 73/13.7, 73/13.8, 73/17.5, 73/17.6, 73/17.7, 73/17.8, 73/17.9, 73/18.1, 734/321, 738/654, 738/658, 377/1, 377/13, 377/15, 377/17, 377/19, 377/20, 377/24, 377/24.1, 377/24.2, 702/1, 702/85, 702/97, 702/104, 702/127, 702/141, 702/150, 702/155, 702/158, 702/160, 702/187, 702/189, 708/100, 708/101, 708/105, 708/131, 708/160, 708/200, 708/212
• US Class Current: 702/160
• CPC Class Codes: G01B 21/02 for measuring length, width, or thickness G01B21/10 takes precedence
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

A method for monitoring human activity using an inertial sensor includes continuously determining an orientation of the inertial sensor, assigning a dominant axis, updating the dominant axis as the orientation of the inertial sensor changes, and counting periodic human motions by monitoring accelerations relative to the dominant axis.

Claims

1. A method of monitoring human activity using an inertial sensor, comprising:

assigning a dominant axis with respect to gravity based on an orientation of the inertial sensor;

detecting a change in the orientation of the inertial sensor and updating the dominant axis based on the change; and

counting periodic human motions by monitoring accelerations relative to the dominant axis by counting the periodic human motions when accelerations showing a motion cycle that meets motion criteria is detected within a cadence window; and

updating the cadence window as actual cadence changes.

2. The method of claim 1, further comprising:

using acceleration measurements along only the dominant axis to count steps.

3. The method of claim 1, wherein at least one of the motion criteria is a dynamic motion criterion, the dynamic motion criterion updated to reflect current conditions.

4. The method of claim 3, wherein the dynamic motion criteria includes at least a lower threshold, wherein the lower threshold is adjusted based on at least one of a rolling average of accelerations and the orientation of the inertial sensor.

5. A method of monitoring human activity using an inertial sensor, comprising:

buffering a plurality of periodic human motions, each periodic human motion comprising a motion cycle;

identifying a number of periodic human motions within an appropriate cadence window;

counting each of the periodic human motions to enable the monitoring of human activity; and

updating the cadence window as a cadence of the motion cycle changes.

6. The method of claim 5, further comprising:

switching the device from the active mode to the non-active mode when a number of expected periodic human motions are not identified in the appropriate cadence windows.

7. The method of claim 5, further comprising:

switching from a sleep mode to the non-active mode of operation when an acceleration is detected.

8. The method of claim 5, wherein prior to identifying, the inertial sensor is in a non-active mode, and wherein the non-active mode comprises running the device in one of an exit mode and an entry mode.

9. The method of claim 8, wherein:

a requirement for switching the device from the exit mode to an active mode is lower than a requirement for switching the device from the entry mode to the active mode.

10. An inertial sensor based device, comprising:

a dominant axis logic to determine an orientation of a device with respect to gravity, to assign a dominant axis, and to update the dominant axis when the orientation of the device changes; and

a counting logic to count periodic human motions by monitoring accelerations relative to the dominant axis by counting the periodic human motions when accelerations showing a motion cycle that meets motion criteria is detected within a cadence window; and

a cadence logic to update the cadence window as actual cadence changes.

11. The device of claim 10, wherein:

the counting logic uses acceleration measurements along only the dominant axis to count steps.

12. The device of claim 10, further comprising:

the cadence logic to update a dynamic cadence window; and

the counting logic to count a periodic human motion when an acceleration measurement that meets motion criteria is taken within the cadence window.

13. The device of claim 10, further comprising:

a comparator, to compare measurements of acceleration to dynamic motion criteria, the dynamic motion criteria updated to reflect current conditions; and

the counting logic to count a periodic human motion when the measurements of acceleration satisfy the dynamic motion criteria.

14. A non-transitory machine readable medium containing executable computer program instructions which, when executed by a processing system, cause said system to perform a method for:

assigning a dominant axis with respect to gravity based on an orientation of the inertial sensor;

detecting a change in the orientation of the inertial sensor and update the dominant axis based on the change; and

counting periodic human motions by monitoring accelerations relative to the dominant axis by counting the periodic human motions when accelerations showing a motion cycle that meets motion criteria is detected within a cadence window; and

updating the cadence window as actual cadence changes.

15. The non-transitory machine readable medium containing executable computer program instructions of claim 14, which, when executed by the processing system, cause said system to perform the method further for:

using acceleration measurements along only the dominant axis to count steps.

16. The non-transitory machine readable medium containing executable computer program instructions of claim 14, which, when executed by the processing system, cause said system to perform the method further for:

switching the device from an active mode to a non-active mode when a number of expected periodic human motions are not identified in the appropriate cadence windows.

17. The non-transitory machine readable medium containing executable computer program instructions of claim 14, which, when executed by the processing system, cause said system to perform the method further for:

maintaining a cadence window, wherein the cadence window is updated as an actual cadence changes; and

counting a periodic human motion when an acceleration measurement that meets motion criteria is within the cadence window.

18. The non-transitory machine readable medium containing executable computer program instructions of claim 17, wherein at least one of the motion criteria is a dynamic motion criterion, the dynamic motion criterion updated to reflect current conditions.

19. The non-transitory machine readable medium containing executable computer program instructions of claim 14, wherein the dynamic motion criteria includes at least a lower threshold, wherein the lower threshold is adjusted based on at least one of a rolling average of accelerations and the orientation of the inertial sensor.