Athletic Performance Monitoring System Utilizing Heart Rate Information

• US 20140121471A1
• Filed: 10/25/2013
• Published: 05/01/2014
• Est. Priority Date: 10/26/2012
• Status: Active Grant

• Current Assignee: Nike, Inc.
• Original Assignee: Nike, Inc.
• Inventors: Walker, Steven H.
• Granted Patent: US 10,206,589 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/02433 for infrared radiation
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1112 Global tracking of patients, e.g. by using GPS
• CPC Class Codes: A61B 5/1128 using image analysis A61B5/1127 takes precedence
• CPC Class Codes: A61B 5/4812 Detecting sleep stages or cycles
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/6844 Monitoring or controlling distance between sensor and tissue
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick

Abstract

An illumination source may be configured to illuminate the skin of the user. An illumination detector may detect electromagnetic radiation reflected of the skin of the user. A compensation module may be configured to determine the position of the skin of the user relative to the illumination detector. A processor may be configured to determine a heart rate of the user by analyzing information corresponding to an amount of the electromagnetic radiation detected by the illumination detector. The processor may also determine the heart rate of the user by compensating for the position of the skin of the user as determined by the compensation module.

Claims

1. A method of determining heart rate, the method comprising:

(a) illuminating skin of a user with an illumination source;

(b) detecting electromagnetic radiation reflected off the skin of the user with an illumination detector;

(c) determining a position of the skin of the user relative to the illumination detector based on the electromagnetic radiation reflected; and

(d) determining, at a processor, a heart rate of the user by analyzing information corresponding to the electromagnetic radiation reflected and compensating for the position of the skin of the user.

2. The method of claim 1, wherein the illumination source comprises at least one light-emitting diode (LED).

3. The method of claim 2 wherein the at least one LED is configured to generate infrared (IR) illumination.

4. The method of claim 1 wherein the illumination detector comprises a photodiode.

5. The method of claim 1 wherein:

the illumination source is a near-field illumination source;

step (a) includes illuminating the skin of the user with a far-field illumination source;

the electromagnetic radiation reflected off the skin of the user and detected by the illumination detector includes a first amount, N, of electromagnetic radiation provided by the near-field illumination source and a second amount, F, of electromagnetic radiation provided by the far-field illumination source; and

step (c) includes calculating a ratio of the first amount of electromagnetic radiation reflected and the second amount of electromagnetic radiation reflected.

6. The method of claim 5 wherein the ratio is equal to N/F.

7. The method of claim 1 wherein:

step (c) comprises accessing a lookup table that associates skin positions with respective compensation factors; and

step (d) includes receiving a compensation factor associated with the position of the skin of the user and utilizing the compensation factor when determining the heart rate of the user.

8. A heart rate determination system comprising:

an illumination source configured to illuminate skin of a user;

an illumination detector that detects electromagnetic radiation reflected off the skin of the user;

a compensation module configured to determine a position of the skin of the user relative to the illumination detector; and

a processor configured to determine a heart rate of the user by analyzing information corresponding to an amount of the electromagnetic radiation detected by the illumination detector and compensating for the position of the skin of the user determined by the compensation module.

9. The heart rate determination system of claim 8 wherein the illumination source comprises a near-field light-emitting diode (LED) and a far-field light-emitting diode.

10. The heart rate determination system of claim 9 further comprising:

a compensation module that determines a compensation factor based on a ratio of a first amount of electromagnetic radiation, N, provided by the near-field LED that is reflected off the skin of the user and detected by the illumination detector to a second amount of electromagnetic radiation, F, provided by the far-field LED that is reflected of the skin of the user and detected by the illumination detector.

11. The heart rate determination system of claim 10 further comprising:

a lookup table that associates skin positions with respective compensation factors; and

wherein the compensation module is configured to perform a lookup at the lookup table using the ratio and provide a compensation factor associated with the ratio to the processor.

12. The heart rate determination system of claim 9 wherein the illumination source is a first illumination source, the near-field LED is a first near-field LED, and the far-field LED is a first far-field LED and further comprising:

a second illumination source that comprises a second near-field LED and a second far-field LED.

13. The heart rate determination system of claim 12 wherein the first illumination source and the second illumination source are positioned substantially orthogonal to each other.

14. The heart rate determination system of claim 12 wherein:

the first near-field LED is positioned between the illumination detector and the first far-field LED; and

the second near-field LED is positioned between the illumination detector and the second far-field LED.

15. The heart rate determination system of claim 12 further comprising:

a lens element that covers the illumination detector; and

respective lens elements that cover each of the first near-field LED, the second near-field LED, the first far-field LED, and the second far-field LED.

16. The heart rate determination system of claim 8 wherein the illumination detector comprises a photodiode.

17. The heart rate determination system of claim 8 wherein the heart rate determination system is incorporated into a wrist-worn device that is configured to measure movements of an individual wearing the wrist-worn device.

18. An optical detector comprising:

a first illumination source module that includes a first near-field light-emitting diode (LED) configured to provide infrared (IR) illumination and a first far-field LED configured to provide IR illumination;

a second illumination source module positioned orthogonally relative to the first illumination source module that includes a second near-field LED configured to provide IR illumination and a second far-field LED configured to provide IR illumination;

an illumination detector comprising a photodiode positioned proximate to the first near-field LED and the second near-field LED and configured to detect an amount of IR radiation reflected off skin of a user; and

an interface configured to provide information corresponding to the amount of IR illumination reflected off the skin of the user;

wherein the photodiode is offset from at least one centerline of the optical detector.

19. The optical detector of claim 18 wherein the optical detector is incorporated into a heart rate determination system that determines a heart rate of the user based, at least in part, on the information corresponding to the amount of IR radiation reflected off the skin of the user.

20. The optical detector of claim 19 wherein the heart rate determination system is incorporated into a wrist-worn device that is configured to measure movements of an individual wearing the wrist-worn device.