Methods and apparatus for generating data output containing physiological and motion-related information

Abstract

A method of generating data output containing physiological and motion-related information includes sensing physical activity of a subject via at least one motion sensor attached to the subject, sensing physiological information from the subject via at least one photoplethysmography (PPG) sensor attached to the subject, and processing signals from the at least one motion sensor and signals from the at least one PPG sensor into a multiplexed serial data string of physiological information and motion-related information. A plurality of subject physiological parameters can be extracted from the physiological information, and a plurality of subject physical activity parameters can be extracted from the motion-related information. The serial data string is parsed out such that an application-specific interface can utilize the physiological information and motion-related information for an application that generates statistical relationships between subject physiological parameters and subject physical activity parameters in the physiological information and motion-related information.

That which is claimed is: 
     
         1 . A method of generating data output containing physiological and motion-related information, the method comprising:
 sensing physical activity and physiological information from a subject via a single monitoring device attached to the subject, wherein the monitoring device comprises at least one motion sensor for sensing the physical activity and at least one photoplethysmography (PPG) sensor for sensing the physiological information; and   processing signals from the at least one motion sensor and signals from the at least one PPG sensor, via at least one processor, into a multiplexed serial data string of physiological data and motion-related data,   wherein the multiplexed serial data string is configured such that a plurality of subject physiological parameters comprising subject heart rate and at least one of the following can be extracted from the physiological data: subject heart rate variability, subject blood gas level, subject blood flow, subject blood pulse volume, subject blood analyte levels, subject breathing rate, subject breathing volume, subject blood oxygen levels, subject blood pressure, subject VO 2  max, the 1st derivative of at least one subject blood pulse, and the 2nd derivative of at least one subject blood pulse,   wherein the multiplexed serial data string is configured such that a plurality of subject physical activity parameters can be extracted from the motion-related data, and   wherein the multiplexed serial data string is configured such that the physiological data and physical activity data are parsed out individually such that that an application-specific interface (API) can utilize the physiological and physical activity data as required for a particular application.   
     
     
         2 . The method of  claim 1 , wherein the application is configured to generate statistical relationships between the subject physiological parameters and the subject physical activity parameters extracted from the physiological data and motion-related data. 
     
     
         3 . The method of  claim 2 , wherein the application is configured to generate statistical relationships between the subject physiological parameters and the subject physical activity parameters via at least one of the following: principal component analysis, multiple linear regression, machine learning, and Bland-Altman plots. 
     
     
         4 . The method of  claim 1 , further comprising, prior to processing signals from the at least one motion sensor and signals from the at least one PPG sensor into the multiplexed serial data string, removing frequency bands from the signals from the at least one PPG sensor that are outside of a range of interest using at least one band-pass filter to produce pre-conditioned PPG signals, and filtering the pre-conditioned PPG signals to reduce motion artifacts and noise artifacts from the pre-conditioned PPG signals to produce cleaner physiological information. 
     
     
         5 . The method of  claim 4 , wherein the subject is running, and wherein the motion artifacts and/or noise artifacts comprise subject footstep motion artifacts, and wherein filtering the pre-conditioned PPG signals comprises removing the footstep motion artifacts from the pre-conditioned PPG signals. 
     
     
         6 . The method of  claim 4 , wherein filtering the preconditioned PPG signals comprises at least one of the following: FIR (Finite Impulse Response) filtering, IIR (Infinite Impulse Response) filtering, adaptive filtering, phase filtering, and frequency filtering. 
     
     
         7 . The method of  claim 1 , wherein the at least one motion sensor comprises at least one of the following: an optical sensor, an inertial sensor, an electrically conductive sensor, a capacitive sensor, an inductive sensor, an accelerometer, and a blocked channel sensor. 
     
     
         8 . The method of  claim 1 , wherein the at least one PPG sensor comprises at least one optical emitter, at least one optical detector, and at least one light guide. 
     
     
         9 . The method of  claim 1 , wherein the at least one motion sensor and the at least one PPG sensor are integrated into a wearable device. 
     
     
         10 . The method of  claim 9 , wherein the wearable device is configured to be attached to the subject at one or more of the following body locations: an ear, a limb, the nose, and a digit. 
     
     
         11 . The method of  claim 1 , wherein the multiplexed serial data string comprises information on data integrity. 
     
     
         12 . A wearable device, comprising:
 at least one motion sensor for sensing physical activity of a subject wearing the wearable device;   at least one photoplethysmography (PPG) sensor for sensing physiological information from the subject; and   at least one processor configured to process signals from the at least one motion sensor and signals from the at least one PPG sensor into a multiplexed serial data string of physiological data and motion-related data,   wherein the multiplexed serial data string is configured such that a plurality of subject physiological parameters comprising subject heart rate and at least one of the following can be extracted from the physiological data: subject heart rate variability, subject blood gas level, subject blood flow, subject blood pulse volume, subject blood analyte levels, subject breathing rate, subject breathing volume, subject blood oxygen levels, subject blood pressure, subject VO 2  max, the 1st derivative of at least one subject blood pulse, and the 2nd derivative of at least one subject blood pulse,   wherein the multiplexed serial data string is configured such that a plurality of subject physical activity parameters can be extracted from the motion-related data, and   wherein the multiplexed serial data string is configured such that the physiological data and physical activity data are parsed out individually such that that an application-specific interface (API) can utilize the physiological and physical activity data as required for a particular application.   
     
     
         13 . The wearable device of  claim 12 , wherein the at least one motion sensor comprises at least one of the following: an optical sensor, an inertial sensor, an electrically conductive sensor, a capacitive sensor, an inductive sensor, an accelerometer, and a blocked channel sensor. 
     
     
         14 . The wearable device of  claim 12 , wherein the at least one PPG sensor comprises at least one optical emitter, at least one optical detector, and at least one light guide. 
     
     
         15 . The wearable device of  claim 12 , wherein the wearable device is configured to be attached to the subject at one or more of the following body locations: an ear, a limb, nose, and a digit. 
     
     
         16 . The wearable device of  claim 12 , wherein the wearable device is an audio earbud. 
     
     
         17 . The wearable device of  claim 16 , wherein the PPG sensor is configured to sense physiological information from at least a portion of the antitragus region of an ear of the subject. 
     
     
         18 . The wearable device of  claim 12 , wherein the multiplexed serial data string comprises information on data integrity. 
     
     
         19 . The wearable device of  claim 12 , further comprising at least one band-pass filter configured to produce pre-conditioned PPG signals by removing frequency bands from the signals from the at least one PPG sensor that are outside of a range of interest. 
     
     
         20 . The wearable device of  claim 19 , further comprising at least one filter configured to filter the pre-conditioned PPG signals to reduce motion artifacts and noise artifacts from the pre-conditioned PPG signals to produce cleaner physiological information. 
     
     
         21 . The wearable device of  claim 20 , wherein the motion artifacts and/or noise artifacts comprise subject footstep motion artifacts caused by the subject running, and wherein the at least one filter is configured to remove the footstep motion artifacts from the pre-conditioned PPG signals. 
     
     
         22 . The wearable device of  claim 20 , wherein the at least one filter comprises at least one of the following: a FIR (Finite Impulse Response) filter, an IIR (Infinite Impulse Response) filter, an adaptive filter, a phase filter, and a frequency filter.