SIGNAL ANALYSIS FOR REPETITION DETECTION AND ANALYSIS

• US 20140270387A1
• Filed: 03/14/2013
• Published: 09/18/2014
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Ahmad, Anis, Hoof, Jonathan R., Kennett, Daniel G.
• Granted Patent: US 9,159,140 B2
• Time in Patent Office: Days
• US Class Current: 382/107
• CPC Class Codes: A63F 13/213 comprising photodetecting means, e.g. cameras, photodiodes or infrared cells A63F13/219, A63F13/655 take precedence
• CPC Class Codes: A63F 13/42 by mapping the input signals into game commands, e.g. mapping the displacement of a stylus on a touch screen to the steering angle of a virtual vehicle
• CPC Class Codes: A63F 13/65 automatically by game devices or servers from real world data, e.g. measurement in live racing competition
• CPC Class Codes: A63F 2300/1087 comprising photodetecting means, e.g. a camera
• CPC Class Codes: A63F 2300/6045 for mapping control signals received from the input arrangement into game commands
• CPC Class Codes: A63F 2300/69 Involving elements of the real world in the game world, e.g. measurement in live races, real video
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06T 7/285 using a sequence of stereo image pairs

Abstract

Techniques described herein use signal analysis to detect and analyze repetitive user motion that is captured in a 3D image. The repetitive motion could be the user exercising. One embodiment includes analyzing image data that tracks a user performing a repetitive motion to determine data points for a parameter that is associated with the repetitive motion. The different data points are for different points in time. A parameter signal of the parameter versus time that tracks the repetitive motion is formed. The parameter signal is divided into brackets that delineate one repetition of the repetitive motion from other repetitions of the repetitive motion. A repetition in the parameter signal is analyzed using a signal processing technique. Curve fitting and/or autocorrelation may be used to analyze the repetition.

Claims

1. A method of analyzing repetitive motion, comprising:

accessing image data that tracks a user performing a repetitive motion;

analyzing the image data to determine a plurality of data points for a parameter, the data points are for different points in time;

forming a parameter signal of the parameter versus time, the parameter signal tracks the repetitive motion;

dividing the parameter signal into a plurality of repetitions of the repetitive motion; and

analyzing a first repetition of the plurality of repetitions in the parameter signal using a signal processing technique.

2. The method of claim 1, wherein the analyzing a first of the plurality of repetitions in the parameter signal using a signal processing technique comprises:

analyzing the parameter signal to compare the first repetition to other repetitions in the parameter signal.

3. The method of claim 2, wherein the analyzing a first of the plurality of repetitions in the parameter signal using a signal processing technique comprises:

auto-correlating a first portion of the parameter signal that corresponds to the first repetition with the parameter signal.

4. The method claim 2, wherein the analyzing a first of the plurality of repetitions in the parameter signal using a signal processing technique comprises:

subtracting a first portion of the parameter signal that corresponds to the first repetition to a second portion of the parameter signal that corresponds to a second repetition of the plurality of repetitions.

5. The method of claim 1, wherein the analyzing a first of the plurality of repetitions in the parameter signal using a signal processing technique comprises:

fitting a curve to a portion of the parameter signal that corresponds to a first repetition of the plurality of repetition.

6. The method of claim 5, further comprising:

determining timing parameters of the first repetition based on the fitted curve.

7. The method of claim 5, wherein the analyzing a first of the plurality of repetitions in the parameter signal using a signal processing technique comprises:

evaluating the user'"'"'s performance of the repetitive motion by comparing the fitted curve to the parameter signal.

8. The method of claim 1, wherein the dividing the parameter signal into a plurality of repetitions of the repetitive motion comprises:

taking a derivative of the parameter signal with respect to time.

9. A system comprising:

a capture device that captures 3D image data that tracks a user performing a repetitive motion;

a processor in communication with the capture device, the processor is configured to;

analyze the 3D image data to determine a plurality of data points for a parameter, the data points are for different points in time;

form a parameter signal of the parameter versus time, the parameter signal tracks the repetitive motion;

divide the parameter signal into a plurality of brackets that divide the parameter signal into a plurality of repetitions of the repetitive motion; and

analyze a first repetition of the plurality of repetitions in the parameter signal using a digital signal processing technique.

10. The system of claim 9, wherein the processor being configured to analyze a first of the plurality of repetitions in the parameter signal using a digital signal processing technique comprises the processor being configured to:

analyze the parameter signal to compare the first repetition to other repetitions in the parameter signal.

11. The system of claim 10, wherein the processor being configured to analyze a first of the plurality of repetitions in the parameter signal using a digital signal processing technique comprises the processor being configured to:

auto-correlate a first bracket of the plurality of brackets with the parameter signal.

12. The system claim 10, wherein the processor being configured to analyze a first of the plurality of repetitions in the parameter signal using a digital signal process comprises the processor being configured to:

subtract a first bracket of the parameter signal that corresponds to the first repetition to a second bracket of the parameter signal that corresponds to a second repetition of the plurality of repetitions.

13. The system of claim 9, wherein the processor being configured to analyze a first of the plurality of repetitions in the parameter signal using a digital signal process comprises the processor being configured to:

fit a curve to a portion of the parameter signal that corresponds to the first repetition; and

determine timing parameters of the first repetition based on points on the fitted curve.

14. The system of claim 9, wherein the processor being configured to divide the parameter signal into a plurality of brackets that divide the parameter signal into a plurality of repetitions of the repetitive motion comprises the processor being configured to:

take a derivative of the parameter signal with respect to time.

15. A computer readable storage device comprising processor readable code for programming a processor to:

access image data that tracks a user exercising;

analyze the image data to determine a plurality of data points for a parameter that tracks a repetitive motion of the user exercising, the data points are for different points in time;

form a parameter signal of the parameter versus time, the parameter signal tracks the repetitive motion;

divide the parameter signal into a plurality of brackets that delineate one repetition of the repetitive motion from other repetitions of the repetitive motion; and

analyze a first repetition in the parameter signal using a digital signal processing technique.

16. The computer readable storage device of claim 15, wherein the processor readable code for programming a processor to analyze a first repetition in the parameter signal using a digital signal processing technique comprises processor readable code for programming a processor to:

auto-correlate a portion of the parameter signal that contains the first repetition with the parameter signal.

17. The computer readable storage device of claim 15, wherein the processor readable code for programming a processor to analyze a first repetition in the parameter signal using a digital signal processing technique comprises processor readable code for programming a processor to:

subtract a first portion of the parameter signal that contains the first repetition to a second portion of the parameter signal that contains a second repetition of the plurality of repetitions.

18. The computer readable storage device of claim 15, wherein the processor readable code for programming a processor to analyze a first repetition in the parameter signal using a digital signal processing technique comprises processor readable code for programming a processor to:

fit a curve to a portion of the parameter signal that contains the first repetition; and

evaluate the user'"'"'s performance of the repetitive motion by comparing the fitted curve to the parameter signal.

19. The computer readable storage device of claim 15, wherein the processor readable code for programming a processor to divide the parameter signal into a plurality of brackets that delineate one repetition of the repetitive motion from other repetitions of the repetitive motion comprises processor readable code for programming a processor to:

take a derivative of the parameter signal with respect to time.

20. The computer readable storage device of claim 15, wherein parameter includes:

a position of a center of mass of the user;

or

a point on a silhouette of the user.