Systems and methods for an advanced pedometer

• US 8,510,079 B2
• Filed: 04/30/2010
• Issued: 08/13/2013
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Aerospace Corporation
• Original Assignee: Aerospace Corporation
• Inventors: Chiou, Kuo-Liang, Osburn, Scot L.
• Primary Examiner(s): Armand, Marc
• Assistant Examiner(s): SUAREZ, FELIX E
• Application Number:
  US12/771,536
• Publication Number:
  US 20110270573A1
• Time in Patent Office: 1,201 Days
• Field of Search: 702/127, 702/141, 702/142, 702/150, 702/160, 702/182, 702/187, 702/188, 345/156, 396/55, 700/253, 701/472
• US Class Current: 702/160
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

Systems and methods are provided for an advanced pedometer, which may include: a first accelerometer for providing first acceleration information for a first direction; a second accelerometer for providing second acceleration information for a second direction; a third accelerometer for providing third acceleration for a third direction; a clock for providing time information associated with the first acceleration information, the second acceleration information, and the third acceleration information; and a processing module comprising one or more processors. The processing module may be to execute computer-executable instructions to: determine fourth level acceleration information for a plane using the first acceleration information for the first direction, and the second acceleration information for the second direction, where the plane is defined by the first direction and the second direction; and estimate a distance traveled using the fourth level acceleration information, the third acceleration information, and at least a portion of the time information.

Claims

1. An advanced pedometer, comprising:

a first accelerometer for providing first acceleration information for a first direction;

a second accelerometer for providing second acceleration information for a second direction;

a third accelerometer for providing vertical acceleration information in a third direction, wherein the first, second, and third directions are independent of each other;

a clock for providing time information associated with the first acceleration information, the second acceleration information, and the third acceleration information; and

a processing module comprising one or more processors, wherein the processing module is configured to receive the first, second, and third acceleration information, and is further configured to execute computer-executable instructions to;

determine a floor level acceleration information for a plane by calculating an absolute magnitude of a combination of the first acceleration information and the second acceleration information, wherein the plane defines a horizontal plane defined by the first direction and the second direction and wherein the third direction is a vertical direction perpendicular to the horizontal plane; and

estimate a distance traveled based on the floor level acceleration information, the vertical acceleration information, and at least a portion of the time information, wherein the distance traveled is estimated independently of any direction information from any directional sensors.

2. The pedometer of claim 1, wherein the processing module is further configured to execute computer-executable instructions to:

estimate one or more errors in the floor level acceleration information and the vertical acceleration information, wherein the one or more errors are estimated responsive to a zero speed determination indicative of no movement,

wherein the estimated one or more errors are utilized to calibrate the floor level acceleration information and the vertical acceleration information to generate calibrated floor level acceleration information and calibrated vertical acceleration information, wherein the calibrated floor level acceleration information and the calibrated vertical acceleration information are utilized to estimate the distance traveled.

3. The pedometer of claim 2, further comprising:

an extended Kalman Filter (EKF), wherein the extended Kalman filter (EKF) having a plurality of error states receives the floor level acceleration information and the vertical acceleration information and estimates the one or more errors.

4. The pedometer of claim 3, wherein the plurality of error states of the extended Kalman filter (EKF) comprise one or more distance error states and one or more speed error states.

5. The pedometer of claim 2, wherein the zero speed determination is based upon the floor level acceleration information and the vertical acceleration information being within predefined threshold values.

6. The pedometer of claim 1, wherein the processing module is further configured to execute computer-executable instructions to:

determine a current total distance traveled by summing a prior total distance traveled and the estimated distance traveled.

7. The pedometer of claim 1, wherein the processing module is further configured to execute computer-executable instructions to:

compensate for an effect of gravity in the floor level acceleration information and the vertical acceleration information to generate gravity-compensated floor level acceleration information and gravity-compensated vertical acceleration information,

wherein the gravity-compensated floor level acceleration information and the gravity-compensated vertical acceleration information are utilized to estimate the distance traveled.

8. The pedometer of claim 1, wherein the processing module is further configured to execute computer-executable instructions to:

estimate a speed using the floor level acceleration information, the vertical acceleration information, and a time associated with the floor level acceleration information and the vertical acceleration information,

wherein the estimated speed is utilized to estimate the distance traveled.

9. The pedometer of claim 1, wherein the floor level acceleration information for a plane is calculated as absolute magnitude of the combination of the first acceleration information and the second acceleration information using a formula a_F=√

{square root over (a_x²+a_y²)}, where a_F is the floor level acceleration information, a_x is the first acceleration information and a_y is the second acceleration information.

10. A method for an advanced pedometer, comprising:

receiving, from a first accelerometer, first acceleration information for a first direction;

receiving, from a second accelerometer, second acceleration information for a second direction;

receiving, from a third accelerometer, vertical acceleration information for a third direction, wherein the first, second, and third directions are independent of each other;

receiving, from a clock, time information associated with the first acceleration information, the second acceleration information, and the third acceleration information;

determining floor level acceleration information for a plane by calculating an absolute magnitude of a combination of the first acceleration information and the second acceleration information, wherein the plane defines a horizontal plane defined by the first direction and the second direction and wherein the third direction is a vertical direction perpendicular to the horizontal plane;

estimating a distance traveled based on the floor level acceleration information, the vertical acceleration information, and a time associated with the floor level acceleration information and the vertical acceleration information, wherein the distance traveled is estimated independently of any direction information from any directional sensors; and

wherein the above operations are performed by one or more processors or application specific integrated circuits (ASICs) associated with a processing module.

11. The method of claim 10, further comprising:

estimating one or more errors in the floor level acceleration information and the vertical acceleration information, wherein the one or more errors are estimated responsive to a zero speed determination indicative of no movement,

wherein the estimated one or more errors are utilized to calibrate the floor level acceleration information and the vertical acceleration information to generate calibrated floor level acceleration information and calibrated vertical acceleration information, wherein the calibrated floor level acceleration information and the calibrated vertical acceleration information are utilized to estimate the distance traveled,

wherein the above operation is performed by one or more processors or application specific integrated circuits (ASICs) associated with the processing module.

12. The method of claim 11, wherein an extended Kalman filter (EKF) having a plurality of error states receives the floor level acceleration information and the vertical acceleration information and is utilized to estimate the one or more errors.

13. The method of claim 12, wherein the plurality of error states of the extended Kalman filter (EKF) comprise one or more distance error states and one or more speed error states.

14. The method of claim 11, wherein the zero speed determination is based upon the floor level acceleration information and the vertical acceleration information being within predefined threshold values.

15. The method of claim 10, further comprising:

determining a current total distance traveled by summing a prior total distance traveled and the estimated distance traveled,

wherein the above operation is performed by one or more processors or application specific integrated circuits (ASICs) associated with the processing module.

16. The method of claim 10, further comprising:

compensating for an effect of gravity in the floor level acceleration information and the vertical acceleration information to generate gravity-compensated floor level acceleration information and gravity-compensated vertical acceleration information,

wherein the gravity-compensated floor level acceleration information and the gravity-compensated vertical acceleration information are utilized to estimate the distance traveled,

wherein the above operation is performed by one or more processors or application specific integrated circuits (ASICs) associated with the processing module.

17. The method of claim 10, further comprising:

estimating a speed using the floor level acceleration information, the vertical acceleration information, and a time associated with the floor level acceleration information and the vertical acceleration information,

wherein the estimated speed is utilized to estimate the distance traveled,

wherein the above operation is performed by one or more processors or application specific integrated circuits (ASICs) associated with the processing module.

18. The method of claim 10, wherein the floor level acceleration information for a plane is calculated as absolute magnitude of the combination of the first acceleration information and the second acceleration information using a formula a_F=√

{square root over (a_x²+a_y²)}, where a_F is the floor level acceleration information, a_x is the first acceleration information and a_y is the second acceleration information.