SYSTEMS AND METHODS FOR OBTAINING BODY FUNCTION MEASUREMENTS USING MOBILE DEVICES - Patent application

Abstract

A system and method are provided for obtaining at least one physical function measurement of a user operating a mobile device. A method, system, computer-readable medium, and apparatus for obtaining at least one physical function measurement are presented. A mobile device includes an exterior housing configured for carrying by a user, a processor housed within the exterior housing, and multiple sensors physically coupled to the exterior housing. The sensors are configured to obtain a first measurement indicative of blood volume and a second measurement indicative of cardiac electrical activity in response to a user action. A blood pressure measurement is determined based on the first and second measurements. The multiple sensors also include electrodes, and portions of the user's body positioned between the electrodes complete a circuit to complete a measurement that provides at least one indication of impedance associated with the user's body. A hydration level measurement is determined based on the impedance indication.

Description

[Technical field]

[0001] Aspects of the present disclosure relate to mobile devices, and more particularly, to systems and methods for obtaining at least one physical function measurement of a user operating a mobile device. [Background technology]

[0002] It may be desirable for a user to know their physical function measurements that can provide physiological indicators of stress, hydration, and other indicators of overall health. Physiological indicators of stress can be used to communicate instructions to the user to modify their behavior, such as to take a break, take a deep breath, etc. Hydration indicators may be used by athletes or generally active individuals to ensure they stay hydrated and maintain physical performance. Additionally, this information may be useful for individuals who work in hot or dry environments and must maintain adequate hydration. Additionally, this information may be useful for elderly individuals whose sense of hydration is reduced and who are more susceptible to dehydration. Important physical function measurements may therefore include measurements of the user's blood pressure and / or hydration status.

[0003] A pulse measurement device may be used to measure a user's blood pressure. A typical pulse measurement device measures a user's pulse using either photoplethysmography (PPG) or electrocardiography (ECG). Using a technique known as pulse transit time (PTT), a combination of PPG and ECG may be used to determine a user's systolic or diastolic blood pressure. Systolic blood pressure, along with other inputs such as pulse rate variability (PRV) and galvanic skin response (GSR), may be useful in determining a physiological indicator of a user's stress. However, existing mobile device solutions for obtaining PPG and ECG measurements are only capable of obtaining measurements for one or the other. That is, existing mobile device solutions may only obtain PPG or ECG measurements, but not both.

[0004] A user's hydration status can be determined by measuring total body water using bioelectric impedance analysis (BIA). BIA measurements are typically accurate and can be within 200 ml of the actual value when performed properly. Existing solutions for measuring BIA typically require specialized equipment in a clinical environment. Furthermore, some existing devices that measure BIA outside of a clinical environment are not very mobile, e.g., cannot fit in a user's pocket or cannot be incorporated into another device that users typically carry with them at all times.

[0005] Therefore, a mobile solution is needed to obtain both PPG and ECG measurements used to determine a user's blood pressure, and to obtain body water content used to determine a user's hydration status. Summary of the Invention [Means for solving the problem]

[0006] Particular embodiments are described for obtaining at least one physical function measurement of a user operating a mobile device.

[0007] In some embodiments, a mobile device for obtaining at least one physical function measurement comprises an exterior body configured to be sized to be carried by a user, a processor housed within the exterior body, and a plurality of sensors physically coupled to the exterior body for obtaining data accessible by the processor. One or more of the sensors are configured to obtain a first measurement indicative of blood volume in response to a user action, and at least one of the sensors configured to obtain the first measurement is housed within a contact button coupled to the exterior body. One or more of the sensors are configured to obtain a second measurement indicative of cardiac electrical activity in response to the user action. The processor is configured to assist in generating a blood pressure measurement based on the first measurement and the second measurement.

[0008] In some embodiments, the mobile device is configured to perform primary and auxiliary functions, and the processor is configured to assist in generating blood pressure measurements as the auxiliary function of the mobile device.

[0009] In some embodiments, the first measurement indicative of blood volume comprises a photoplethysmography (PPG) measurement.

[0010] In some embodiments, the second measurement indicative of the heart's electrical activity includes an electrocardiography (ECG) measurement.

[0011] In some embodiments, one or more of the sensors configured to obtain the first measurement comprise at least one optical sensor, and the mobile device further comprises at least one light source, the at least one optical sensor measuring reflected light from the light source reflected from a blood vessel in a user of the mobile device to obtain the first measurement.

[0012] In some embodiments, the at least one optical sensor includes an infrared (IR) light emitting diode (LED).

[0013] In some embodiments, one or more of the sensors configured to obtain a second measurement indicative of the cardiac electrical activity comprises at least a first electrode and a second electrode, and a body part of a user of the mobile device completes a circuit between the first electrode and the second electrode.

[0014] In some embodiments the mobile device is a watch.

[0015] In some embodiments, the mobile device is a smartphone device.

[0016] In some embodiments, a method for obtaining at least one physical function measurement via a mobile device includes obtaining a first measurement indicative of blood volume in response to a user action via a plurality of sensors physically coupled to an exterior body of the mobile device, at least one of the sensors being contained within a contact button coupled to the exterior body. The method further includes obtaining a second measurement indicative of cardiac electrical activity in response to the user action via the plurality of sensors. The method also includes facilitating generation of a blood pressure measurement based on the first measurement and the second measurement via a processor of the mobile device, the processor being contained within an exterior body of the mobile device, the exterior body being configured with a size such that it can be carried by a user.

[0017] In some embodiments, an apparatus for obtaining at least one physical function measurement comprises means for obtaining a first measurement indicative of blood volume in response to a user action via a plurality of sensors physically coupled to an exterior body of a mobile device, at least one of the sensors being contained within a contact button coupled to the exterior body. The apparatus further comprises means for obtaining a second measurement indicative of cardiac electrical activity in response to the user action via the plurality of sensors. The apparatus also comprises means for assisting in generating a blood pressure measurement based on the first measurement and the second measurement via a processor of the mobile device, the processor being contained within the exterior body of the mobile device, the exterior body being configured in a size such that it can be carried by a user.

[0018] In some embodiments, one or more non-transitory computer-readable media storing computer-executable instructions for obtaining at least one body function measurement, the instructions, when executed, causing one or more computing devices contained within the mobile device to obtain a first measurement indicative of blood volume in response to a user action via a plurality of sensors physically coupled to an exterior body of the mobile device, at least one of the sensors being contained within a contact button coupled to the exterior body. The computer-executable instructions, when executed, further cause the one or more computing devices contained within the device to obtain a second measurement indicative of cardiac electrical activity in response to the user action via the plurality of sensors. The computer-executable instructions, when executed, cause the one or more computing devices contained within the device to assist in generating a blood pressure measurement based on the first measurement and the second measurement, via a processor of the mobile device, the processor being contained within an exterior body of the mobile device, the exterior body being configured with a size such that it can be carried by a user.

[0019] In some embodiments, a mobile device for obtaining at least one physical function measurement comprises an enclosure configured to be sized to be carried by a user, a processor housed within the enclosure, and a plurality of sensors physically coupled to the enclosure for obtaining data accessible by the processor. The plurality of sensors comprises electrodes, where portions of the user's body located between the electrodes complete a circuit to complete a measurement that provides at least one indication of impedance associated with the user's body in response to a user action. The processor is configured to assist in generating a hydration level measurement based on the indication of impedance.

[0020] In some embodiments, the mobile device is configured to perform primary and auxiliary functions, and the processor is configured to assist in generating the hydration level measurements as the auxiliary function of the mobile device.

[0021] In some embodiments, at least one of the sensors is incorporated into a multi-functional surface, the multi-functional surface being configured to simultaneously obtain impedance measurements and user input.

[0022] In some embodiments, the multi-functional surface comprises silver metal.

[0023] In some embodiments, the multi-functional surface comprises indium tin oxide (ITO).

[0024] In some embodiments the mobile device is a watch.

[0025] In some embodiments, the mobile device is a smartphone device.

[0026] In some embodiments, a method for obtaining at least one body function measurement via a mobile device includes obtaining measurements providing at least one indication of impedance associated with a user's body in response to a user action via a plurality of sensors comprising electrodes and physically coupled to an exterior body of the mobile device, a portion of the user's body located between the electrodes completing a circuit, and facilitating generation of a hydration level measurement based on the indication of impedance via a processor of the mobile device, the processor being contained within the exterior body of the mobile device, the exterior body being configured with a size such that it can be carried by a user.

[0027] In some embodiments, an apparatus for obtaining at least one body function measurement via a mobile device comprises means for obtaining, via a plurality of sensors comprising electrodes and physically coupled to an exterior body of the mobile device, measurements providing at least one indication of impedance associated with a user's body in response to a user action, with a portion of the user's body located between the electrodes completing a circuit, the apparatus further comprises means for assisting in generating a hydration level measurement based on the indication of impedance via a processor of the mobile device, the processor being contained within the exterior body of the mobile device, the exterior body being configured in a size such that it can be carried by a user.

[0028] In some embodiments, one or more non-transitory computer-readable media storing computer-executable instructions for obtaining at least one body function measurement, the instructions, when executed, causing one or more computing devices contained within the mobile device to obtain measurements providing at least one indication of impedance associated with the user's body in response to a user action via a plurality of sensors comprising electrodes and physically coupled to an exterior body of the mobile device, a portion of the user's body located between the electrodes completing a circuit, the computer-executable instructions, when executed, further causing the one or more computing devices contained within the device to assist in generating a hydration level measurement based on the indication of impedance via a processor of the mobile device, the processor being contained within an exterior body of the mobile device, the exterior body being configured in a size such that it can be carried by a user.

[0029] Aspects of the present disclosure are illustrated by way of example in the accompanying drawings, in which like reference numbers indicate similar elements and in which: [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 illustrates a mobile device configured to obtain PPG and ECG measurements of a user, according to some implementations. [Diagram 2] FIG. 1 illustrates a smartphone device configured to obtain PPG and ECG measurements of a user, according to some embodiments. [Diagram 3] FIG. 1 illustrates a watch device configured to obtain PPG, ECG and impedance measurements according to some embodiments. [Figure 4A] 4 illustrates a cross-sectional view of the watch device of FIG. 3 and a graph illustrating measurements taken by the watch device, according to some embodiments. [Figure 4B]4 is a cross-sectional view of the watch device of FIG. 3 in which a sensor for obtaining PPG measurements is housed within a contact button of the watch device, according to some embodiments. [Figure 4C] FIG. 4 is a top view of the watch device of FIG. 3, in which a sensor for obtaining PPG measurements is housed within a contact button of the watch device, according to some embodiments. [Figure 4D] 1 is a graph comparing cardiac activity measurements between a PPG sensor housed in a contact button and a wrist-based PPG sensor, according to some embodiments. [Diagram 5] 1 is a schematic diagram illustrating a method for obtaining impedance measurements of a user, according to some embodiments. [Figure 6] FIG. 13 is a schematic diagram of two resistors and one capacitor representing conduction through tissue, according to some embodiments. [Figure 7] 1 is a flow diagram illustrating derived metrics from sensor metrics according to some embodiments. [Figure 8] 1 is a flow diagram of an exemplary method for obtaining at least one physical function measure. [Figure 9] 13 is another flow diagram of an exemplary method for obtaining at least one physical function measure. [Figure 10] FIG. 1 illustrates an example of a computing system in which one or more embodiments may be implemented. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Several exemplary embodiments will now be described with reference to the accompanying drawings, which form a part of this specification. Specific embodiments capable of implementing one or more aspects of the present disclosure are described below, but other embodiments may be used and various changes may be made without departing from the spirit of the scope of the disclosure or the appended claims.

[0032] 1 illustrates a schematic block diagram of a mobile device 100 that may incorporate one or more embodiments. The mobile device 100 includes a processor 110, a microphone 120, a display 130, an input device 140, a speaker 150, a memory 160, a camera 170, a sensor 180, a light source 185, and a computer-readable medium 190.

[0033] The processor 110 may be any general-purpose processor operable to execute instructions on the mobile device 100. The processor 110 is coupled to other units of the mobile device 100, including a microphone 120, a display 130, an input device 140, a speaker 150, a memory 160, a camera 170, a sensor 180, a light source 185, and a computer-readable medium 190.

[0034] The microphone 120 may be any acoustic-to-electrical transducer or sensor that converts sound into an electrical signal. The microphone 120 may provide the ability for a user of the mobile device 100 to record audio signals or issue voice commands for the mobile device 100.

[0035] Display 130 can be any device that displays information to a user. Examples can include an LCD screen, a CRT monitor, or a seven-segment display.

[0036] The input device 140 can be any device that receives input from a user. Examples include a keyboard, a keypad, or a mouse. In some embodiments, the microphone 120 can also serve as the input device 140.

[0037] Speaker 150 can be any device that outputs sound to a user. Examples can include a built-in speaker or any other device that produces sound in response to electrical audio and / or ultrasonic signals.

[0038] Memory 160 can be any magnetic, electronic, or optical memory. Memory 160 includes two memory modules, module 1 162 and module 2 164. It will be appreciated that memory 160 may include any number of memory modules. One example of memory 160 can be a dynamic random access memory (DRAM).

[0039] The camera 170 is configured to capture one or more images through a lens located on the body of the mobile device 100. The captured images can be still images or video images. The camera 170 can include a CMOS image sensor that captures images. Various applications executing on the processor 110 can access the camera 170 to capture images. It will be appreciated that the camera 170 can continually capture images without the images actually being stored within the mobile device 100. The captured images may also be referred to as image frames.

[0040] The sensor 180 may be a number of sensors configured to obtain data accessible by a processor. The sensor 180 may also be physically coupled to the exterior body of the mobile device 100. The number of sensors 180 may include one or more optical sensors 182 and / or one or more electrodes 184. The optical sensor 182 is configured to assist in measuring reflected light from a light source 185 (described later) reflected from blood vessels in a user of the mobile device 100 to obtain a PPG measurement indicative of the user's blood volume. For example, when a user touches both the first electrode and the second electrode, a body part of the user of the mobile device 100 may complete a circuit between both electrodes 184. The electrodes 184 may be configured to assist in measuring the electrical activity of the user's heart to obtain an ECG measurement. The electrodes 184 may also be configured to assist in measuring the impedance of the user of the mobile device 100 to obtain a level measurement.

[0041] The light source 185 may be any light source configured to emit light through the user's body. In some embodiments, the light source 185 may be an LED light source. The emitted light may be of wavelengths that can pass through multiple parts of the user's body. For example, the light source 185 may emit LED light through the user's wrist. In some embodiments, the mobile device 100 may include multiple light sources 185. The light emitted from the light source 185 may reflect off blood vessels in the user's body, and the reflected light may be measured by one or more light sensors 182 to obtain PPG measurements, as described above. It will be appreciated that the emitted light may be of different wavelengths depending on the different wavelengths. For example, different wavelengths of light may be suitable to improve the signal, reduce noise, deal with dark skin tones, measure the oxygen content of blood, or penetrate different depths of the user's body.

[0042] The computer readable medium 190 may be any magnetic, electronic, optical or other computer readable storage medium. The computer readable storage medium 190 includes a PPG measurement module 192, an ECG measurement module 194, a blood pressure measurement module 196, an impedance measurement module 198, and a hydration level measurement module 199.

[0043] The PPG measurement module 192, when executed by the processor 110, is configured to obtain photoplethysmography (PPG) measurements. The PPG measurements may be measurements of the blood volume of a user operating the mobile device 100. The PPG measurements may be obtained by the PPG measurement module 192 in response to a user action. The PPG measurement module 192 may interface with the light source 185 and the light sensor 182 to obtain the PPG measurements. Upon a user indication that a PPG measurement is required, the PPG measurement module 192 may instruct the light source 185 or multiple light sources to emit light into the user's body. As described above, the emitted light may be reflected from or transmitted through blood vessels in the user's body and may be detected by one or more light sensors 182 in the mobile device 100. The PPG measurement module 192 may interface with one or more light sensors to measure the amount of reflected or transmitted light detected by the one or more light sensors 182. The PPG measurement module 192 can then determine a PPG measurement, indicative of the user's blood volume, based on the reflected light measurement.

[0044] The ECG measurement module 194, when executed by the processor 110, is configured to obtain electrocardiography (ECG) measurements. The ECG measurements may be measurements of electrical activity of the heart of a user operating the mobile device 100. The ECG measurements may be obtained by the ECG measurement module 194 in response to a user action. The ECG measurement module 194 may be configured to interface with the electrodes 184 to obtain the ECG measurements. Upon a user indication that an ECG measurement is desired, the ECG measurement module 194 may be configured to interface with the electrodes 184 to measure electrical impulses generated by polarization and depolarization of cardiac tissue within the user's body (assuming the user's body completes a circuit between the electrodes 184). In some embodiments, the electrical impulses may be generated by the beating of the user's heart. In some embodiments, the ECG measurement module 194 may be configured to interface with the electrodes 184 to automatically measure the electrical impulses once the user's body completes a circuit between the electrodes 184. The ECG measurement module 194 may then determine an ECG measurement based on the measured electrical impulses. It will be appreciated that ECG measurements may be obtained using more than one electrode lead.

[0045] The blood pressure measurement module 196, when executed by the processor 110, is configured to generate a blood pressure measurement for the user based on the PPG and ECG measurements. Poon, CCY and Zhang, YT, “Cuff-less and Noninvasive Measurements of Arterial Blood Pressure by Pulse Transit Time,” Engineering in Medicine and Biology 27 th According to the IEEE Annual Conference, 2005, pages 1-4, the calculation of blood pressure measurements based on PPG and ECG measurements is well known in the art.

[0046] The impedance measurement module 198, when executed by the processor 110, is configured to obtain impedance measurements. The impedance measurements may indicate a hydration level of a user operating the mobile device 100. The impedance measurements may be obtained by the impedance measurement module 198 in response to a user action. The impedance measurement module 198 may be configured to interface with the electrodes 184 to obtain impedance measurements. Upon indication by the user that an impedance measurement is desired, the impedance measurement module 198 may be configured to interface with the electrodes 184 to measure electrical impedance within the user's body (assuming the user's body completes a circuit between the electrodes 184). In some embodiments, the impedance measurement module 198 may be configured to interface with the electrodes 184 to automatically measure electrical impedance once the user's body completes a circuit between the electrodes 184.

[0047] The hydration level measurement module 199, when executed by the processor 110, is configured to obtain a hydration level measurement based on the impedance measurements obtained by the impedance measurement module 198. The hydration level measurement module 199 can determine the hydration level from the measured impedance using techniques well known in the art.

[0048] It will be appreciated that the exterior of the mobile device 100 can be configured to a size that allows it to be carried by a user. It will be appreciated that the term "portable" can refer to something that can be easily transported or moved, and may be lightweight and / or small. In the context of an embodiment of the present invention, the term "portable" can refer to something that is easily transportable by a user or that can be worn by a user. For example, the mobile device 100 can be a smartphone device, or a wristwatch that can be worn by a user. Other examples of portable devices include head-mounted displays, calculators, portable media players, digital cameras, pagers, personal navigation devices, and the like. Examples of devices that cannot be considered portable include desktop computers, traditional phones, televisions, appliances, and the like. It will be appreciated that the physical function measurements can be obtained via a smartphone, a wristwatch, or any other of the above devices.

[0049] FIG. 2 illustrates a smartphone device 210 configured to obtain PPG and ECG measurements of a user, according to some embodiments. It will be appreciated that the smartphone device 210 is merely one example of a mobile device 100. The smartphone device 210 may include multiple contacts 220. In some embodiments, a single contact 220 may be disposed at each end of the smartphone device 210. In other embodiments, the device front surface 250 of the smartphone device 210 may include a contact layer including silver metal or indium tin oxide (ITO). The smartphone device 210 may obtain both PPG and ECG measurements of a user 260. In some embodiments, the device front surface 250 may be a touch screen.

[0050] For example, a user 260 may hold the smartphone device 210 such that a first hand 240 touches one or more of the contacts 220 and a second hand 230 touches the device front surface 250. When the user 260 performs this action, the contacts 220 and the contact layer on the device front surface 250 may complete a circuit through the user's 260 body. The smartphone device 210 may then measure electrical potentials through the completed circuit to determine an ECG measurement. It will be appreciated that an ECG measurement may also be obtained without the user's first hand 240 or second hand 230 touching the device front surface 250. That is, the user's first hand 240 may touch the first side contact 220 and the user's second hand 230 may touch the second side contact 220 to complete the circuit. Alternatively, the user 260 can contact both side contacts 220 using only the first hand 240 or the second hand 230 (see below regarding measuring PPG or galvanic skin response (GSR)). Alternatively, although not shown in FIG. 1, sensors located and / or contacting other locations, e.g., legs, feet, ankles, knees, elbows, arms, neck, head, etc., depending on the location and manner of contact, can be used to generate PPG, GSR, and possibly ECG.

[0051] The device front surface 250 of the smartphone device 210 can also obtain PPG measurements of the user 260 by using optical-based techniques. For example, when the user 260 touches the device front surface 250, the light source 185 can shine light on the skin of the user 260 and one or more sensors can measure the blood flow in the capillaries, thereby determining the user's heart rate (PPG). This process is described in more detail below. In some embodiments, the light source can be a dedicated light source that is part of the smartphone device 210.

[0052] Thus, by obtaining both PPG and ECG measurements of the user 260, the PTT technique can be used to determine the user's blood pressure, and the smartphone device 210 can then provide important information to the user 260 based on the determined blood pressure (as described further below).

[0053] Additionally, the smartphone device 210 can obtain impedance measurements of the user using BIA techniques. In some embodiments, the impedance measurements can be obtained through a contact layer on the device front surface 250. The process of obtaining the impedance measurements is described in more detail below.

[0054] It will be appreciated that the device front face 250 can serve multiple functions. That is, the device front face 250 can be used to obtain ECG, PPG and / or impedance measurements as described above, and can also be used as a user input device. The user 260 can use the device front face 250 to provide input to an application running on the smartphone device 210. When the user 260 wishes to obtain a physical function measurement using the device front face 250, the user 260 can place the smartphone device 210 in a measurement mode. Alternatively, the smartphone device 210 can automatically detect the user's intent to obtain a physical function measurement, for example, from the user 260 placing a finger in a specific location on the device front face 250 or touching the device front face 250 for a predetermined period of time. Alternatively, the smartphone device 210 can periodically scan and store the user's 260 vital signs in the user's normal operation of the device 210, without the user wanting or requesting a specific vital sign report at the time.

[0055] 3 illustrates a watch device 310 configured to obtain PPG, ECG, and impedance measurements of a user, according to some embodiments. The watch device 310 illustrated in FIG. 3 operates similarly to the smartphone device 210 of FIG. 2. That is, the watch device 310 can obtain PPG, ECG, and impedance measurements of a user 260 through multiple contacts. In some embodiments, one or more contacts can be disposed at the bottom of the watch device 310, and the contacts are in constant contact with the wrist of the user 260 while the user 260 is wearing the watch device 310.

[0056] The watch device 310 may also include a multi-function button 320, which may be used to obtain physical function measurements and may also be used as a user input device. For example, the multi-function button 320 may be used by the user 260 to set the date and / or time for the watch device 310. The multi-function button may have electrodes integrated on its surface. The user 260 may also use the multi-function button 320 to obtain ECG measurements by touching the button 320 to complete a circuit (through other contacts) through the user's body. In some embodiments, the multi-function button 320 may be incorporated within a touch screen of the watch device 310.

[0057] PPG and hydration measurements can be obtained, for example, via contacts on the watch device 310 in a manner similar to that described with respect to the smartphone device of Figure 2. PPG measurements can also be obtained using optical techniques, as described below.

[0058] The watch device 310 can be designed to be portable so that the user can easily wear or carry the device on their body. In some embodiments, the watch device 310 can perform everyday functions other than obtaining PPG, ECG and impedance measurements of the user. For example, the watch device 310 can provide the current time, a stopwatch function, a calendar function, communication functions, etc. The PPG, ECG and impedance measurement functions can be made available in addition to the other above-mentioned functions on the watch device 310.

[0059] 4A illustrates a cross-sectional view 410 of the watch device 310 of FIG. 3 and graphs 420, 430, 440 illustrating measurements obtained by the watch device, according to some embodiments. The cross-sectional view 410 of the watch device 310 illustrates a photodetector 412, a number of light emitting diodes (LEDs) 414, and a number of electrode contacts 416. Additionally, the cross-sectional view 410 illustrates a portion of a user's wrist, e.g., a radius 418 and an ulna 419. In some embodiments, the number of LEDs 414 can be infrared (IR) LEDs. IR LEDs can provide advantages to the user, such as not distracting the user from normal operation of the watch device 310, since they may not emit any visible light.

[0060] The watch device 310 can obtain a PPG measurement of the user by using optical techniques. To obtain a PPG measurement, an LED 414 (typically located at the bottom of the watch device 310 and on the top of the user's wrist) can emit light into the user's skin. The reflected light can be received at a photodetector 412. Based on the reflected light as compared over time, the user's blood volume can be determined. From this data, the user's PPG measurement can be determined. In some embodiments, the determination of the user's blood volume can be determined from a change in the user's blood volume, and more specifically, from a change in the diameter of the blood vessel being probed by the LED 414.

[0061] Additionally, the plurality of contacts 416 may be used to obtain an ECG measurement of the user, as described above with respect to Figure 3. It will be appreciated that in an embodiment of the watch device 310, the plurality of contacts 416 may be in constant contact with the user's skin while the user is wearing the watch device 310 on their wrist, whereupon the user may use a hand not wearing the watch device 310 to touch another contact 416 located elsewhere on the watch device 310 to complete a circuit through the user's body.

[0062] Similarly, multiple contacts 416 may be used to obtain a hydration measurement of the user by determining impedance through the user's body.

[0063] Graph 420 shows the intensity of the light reflection obtained at the photodetector 412 versus time. In this example, the duration between each pulse is about 1 second. From this graph, the user's PPG can be determined.

[0064] Graph 430 shows the user's heart rate variability by comparing the user's ECG with the user's PPG. As shown in graph 440, the PPT can be determined by taking the difference between the peak of the ECG pulse and the corresponding inflection point of the PPG pulse (which is in the same time interval). The user's blood pressure can then be determined using the PTT, as is well known in the art.

[0065] 4B shows a cross-sectional view of the watch device 310 of FIG. 3 in which a sensor for obtaining PPG measurements is housed within a contact button of the watch device, according to some embodiments. In contrast to the watch device shown in FIG. 4A, the watch device 310 shown in FIG. 4B includes a PPG sensor 470 within a contact button 460 on the watch device 310. To determine a PPG measurement, a user can place their finger on the contact button 460 such that the PPG sensor 470 can obtain a PPG signal from the finger. In some embodiments, the PPG sensor 470 can be an optical sensor.

[0066] By locating the PPG sensor 470 within the contact button 460, several advantages can be realized, including, but not limited to, allowing a quicker and more accurate readout of the PPG signal from the user's finger as opposed to the user's wrist. This results in a quicker identification of the user's PPT. The PPG sensor 470 within the contact button 460 can provide better results than measuring PPG from the arm / wrist due to the vascularization of the arm associated with obtaining a PPG measurement from the arm. That is, the arteries near the surface of the arm where the measurement is being obtained may obscure the signal due to the multiple paths that the blood takes in a cloud. However, in the fingers, the arteries typically extend along the inside between the user's fingers to the tip of the finger before spreading out into multiple capillaries. Thus, a clear signal can be obtained from the finger.

[0067] In some embodiments, the contact button 460 can be a multi-function button operable to perform other functions of the watch device 310. For example, the multi-function button can be used to interact with the watch device 310 to set the time, to start / stop the stopwatch, or for any other function typically available within the watch device 310.

[0068] In the implementation of Figure 4B, the watch device 310 may also, according to some embodiments, obtain ECG measurements as described with respect to Figure 4A, by having the electrical contacts 416 contact the user's arm / wrist and the contact button 460 contact the user's finger, thereby completing a circuit. Advantageously, when the user contacts their finger with the contact button 460, both ECG and PPG measurements may be obtained.

[0069] 4C shows a top view of the watch device of FIG. 3 where a sensor for obtaining PPG measurements is housed within a contact button of the watch device, according to some embodiments. FIG. 4C shows a top view of the watch device 310 described in FIG. 4B. As shown in the figure, the PPG sensor 470 is housed within the contact button 460. The electrical contacts 416 used to obtain ECG measurement data can be located at the bottom of the watch device 310.

[0070] In some embodiments, the contact button 460 can have an opening so that light from the PPG sensor 470 can travel through the opening to obtain an optical PPG measurement. In some embodiments, the contact button 460 can be formed from a material that optimizes metal electrodes, such as stainless steel.

[0071] 4D shows a graph illustrating cardiac activity measurements obtained from PPG measurements taken on a finger, according to some embodiments. The graph shows an electrocardiogram signal 480 and a PPG signal 490 obtained from the finger of a 24-year-old male. It can be seen that the PPG signal 490 is less noisy and the signal is smooth and / or curvilinear. Due to the better resolution of the PPG signal 490 provided by obtaining measurements from a finger rather than the wrist, other information such as cardiac activity can also benefit from higher accuracy. Additional information that can be determined due to the better resolution of the PPG signal 490 includes, but is not limited to, systolic blood pressure, an index of vascular stiffness.

[0072] FIG. 5 is a schematic diagram 500 of a method for obtaining impedance measurements of a user, according to some embodiments. The mobile device can be either a smartphone device as shown in FIG. 2, a watch device as shown in FIG. 3, or any other mobile device. As described above, the impedance measurements of the user can be used to determine the hydration level of the user using BIA techniques. In this illustration, the user's body 510 essentially acts as a capacitance and resistance network. When the user's body 510 contacts the contacts 530, an impedance converter 520 can determine an impedance value through the user's body 510. In this scenario, the user's body 510 can act as a capacitor. The impedance value can be a function of the surface tissue impedance and the deep tissue impedance. The impedance value can then be used to estimate the total body water content of the user's body 510. The diagram shows measuring impedance through one leg, torso and one arm. The method works similarly for measurements through both arms and chest. In some embodiments, the mobile device can include phase detection electronics that distinguish between electrical resistance and reactance.

[0073] Upon determining the user's hydration level, the mobile device may provide notifications to the user, types of notifications are described in further detail with respect to FIG.

[0074] 6 is a schematic diagram 600 of two resistors and one capacitor representing conduction through tissue, according to some embodiments. c represents the capacitance of the user's cell wall, and R (ICW) represents the resistance of the internal water of the user's cells, and R (ECW)represents the resistance of the user's body water outside the cells. The circuit shown in Figure 6 can be used as part of the circuit diagram of Figure 5 to determine the user's hydration level by determining the electrical impedance through the user's body.

[0075] 7 is a flow diagram 700 illustrating multiple derived metrics 720 from multiple sensor metrics 710, according to some embodiments. The multiple sensor metrics 710 may include, but are not limited to, PPG pulse measurements, acceleration measurements, AC bioimpedance measurements, and two-wire ECG heart rate measurements. These sensor metrics 710 may be obtained by making measurements via a mobile device. Based on the data from the sensor metrics 710, multiple derived metrics 720 may be derived. These derived metrics may include, but are not limited to, heart rate, heart rate variability, stress calculations, blood pressure, and hydration status.

[0076] For example, using techniques described herein, when PPG pulse measurements are obtained, the user's heart rate and / or heart rate variability can be determined. The PPG pulse measurements can be combined with ECG heart rate measurements to determine the user's blood pressure using PTT techniques. Based on the determined blood pressure, the user's stress level can be determined. When the user is determined to be at a high stress level, the mobile device can notify the user to take a deep breath, go for a walk, drink water, etc. As illustrated, the stress level can also be determined from the user's GSR data.

[0077] In another example, when AC bioelectrical impedance measurements are obtained using the techniques described herein, the hydration status of a user can be determined from data related to the user's total body water. If the user's hydration status is determined to be low, the mobile device can notify the user to drink water. On the other hand, if the user's hydration status is determined to be sufficient, the mobile device can notify the user to stay well.

[0078] In another example, energy calculations may be based on accelerometer and gyroscope data obtained by the mobile device. For example, if a user is actively moving around, the accelerometer data may indicate a high activity level and the mobile device may determine that the user's energy level is high. The mobile device may notify the user to stay active. In some embodiments, the mobile device may record the user's energy level throughout the day and may notify the user at predetermined intervals to be active in order to reach a daily activity threshold.

[0079] In some embodiments, the accelerometer measurements may be used to determine the user's heart rate and / or heart rate variability. The same calculations as above may be determined / calculated using these measurements.

[0080] It is understood that the specific order or hierarchy of steps in the processes disclosed is an illustration of an example approach. It is understood that the specific order or hierarchy of steps in the processes may be rearranged based on design preferences. Additionally, some steps may be combined or omitted. The accompanying method claims present elements of the various steps in a sample order, and are not intended to be limited to the specific order or hierarchy presented.

[0081] The preceding description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications of these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Furthermore, nothing disclosed herein is intended as a public service.

[0082] 8 is a flow diagram 800 of an exemplary method for obtaining at least one physical function measurement. At block 810, a first measurement indicative of blood volume is obtained in response to a user action. The first measurement may be obtained via a number of sensors physically coupled to a housing of the mobile device. In some embodiments, the first measurement may be a photoplethysmography (PPG) measurement.

[0083] In some embodiments, the plurality of sensors may include at least one optical sensor. The mobile device may also include at least one light source. Obtaining the first measurement may include measuring reflected light from the light source reflected from blood vessels in the user of the mobile device via the at least one optical sensor. For example, in FIG. 3, the wearable watch obtains a PPG measurement of the user via the optical sensor and the light source in the wearable watch. The PPG measurement may be obtained by the PPG measurement module described in FIG. 1.

[0084] At block 820, a second measurement indicative of the electrical activity of the heart is obtained in response to the user action. The second measurement may be obtained via a number of sensors. In some embodiments, the second measurement may be an electrocardiography (ECG) measurement.

[0085] In some embodiments, the plurality of sensors may include at least a first electrode and a second electrode. Obtaining the second measurement may include detecting completion of a circuit between the first electrode and the second electrode via a portion of the user's body. For example, in FIG. 3, the wearable watch obtains an ECG measurement of the user via electrodes located on an exterior body of the wearable watch. The ECG measurement may be obtained by an ECG measurement module described in FIG. 1.

[0086] In block 830, the generation of a blood pressure measurement based on the first and second measurements is facilitated via a processor of the mobile device. The processor can be housed within an exterior body of the mobile device, which can be configured to a size that allows the user to carry it around. In some embodiments, the mobile device can be configured to perform primary and auxiliary functions. Assisting in the generation of the blood pressure measurement may be performed as an auxiliary function of the mobile device. For example, in FIG. 3, a wearable wristwatch can assist in measuring the user's blood pressure based on the obtained PPG and ECG measurements. The blood pressure can be determined by the blood pressure measurement module described in FIG. 1.

[0087] In some embodiments, the mobile device is a watch. For example, in Figure 3, the mobile device is a wearable watch. In other embodiments, the mobile device is a smartphone device. For example, in Figure 2, the mobile device is a smartphone device.

[0088] In some embodiments, at least one of the sensors is incorporated into a multi-function surface, which is configured to simultaneously obtain the first or second measurement and user input. For example, in FIG. 2, a smartphone device (which can also obtain PPG and ECG measurements similar to a wearable wristwatch) includes a multi-function touch screen surface that supports user input into the smartphone device. In one example, the multi-function surface can include:

[0089] In some embodiments, blocks 810 and 820 may be performed by a first device and block 830 may be performed by a second device. That is, the measurement of blood volume and cardiac electrical activity may be performed by a device separate from the generation of the blood pressure measurement. For example, the measurement of blood volume and cardiac electrical activity may be performed via a communication device worn by a user, while the generation of the blood pressure measurement may be performed by a server computer that receives the indications of blood volume and cardiac electrical activity from the communication device. In some embodiments, the server computer may reside in a cloud system.

[0090] 9 is another flow diagram 900 of an exemplary method for obtaining at least one body function measurement. At block 910, a measurement is obtained that provides at least one indication of an impedance associated with the user's body in response to a user action. In some embodiments, the measurement may be obtained via a plurality of sensors that include electrodes physically coupled to an exterior body of the mobile device. In some embodiments, a portion of the user's body disposed between the electrodes completes a circuit.

[0091] For example, in Figure 3, the wearable watch obtains impedance measurements of the user via electrodes located on the exterior body of the wearable watch. The impedance measurements may be obtained by the impedance measurement module shown in Figure 1.

[0092] At block 920, generation of a hydration level measurement based on the impedance indicator is facilitated via a processor of the mobile device. In some embodiments, the processor is housed within an exterior body of the mobile device. In some embodiments, the exterior body is sized to be portable by a user.

[0093] In some embodiments, the mobile device is configured to perform a primary function and an auxiliary function. In some embodiments, the processor is configured to assist in generating a hydration level measurement as an auxiliary function of the mobile device. For example, in FIG. 3, the wearable watch can assist in measuring a user's hydration level based on the impedance measurements obtained. The hydration level can be determined by the hydration level measurement module described in FIG. 1.

[0094] In some embodiments, at least one of the sensors is incorporated into a multi-functional surface. In some embodiments, the multi-functional surface is configured to simultaneously obtain impedance measurements and user input. In some embodiments, the multi-functional surface comprises indium tin oxide (ITO). In some embodiments, the multi-functional surface comprises silver metal. In some embodiments, the multi-functional surface comprises a network of wires or transparent conductors. For example, in FIG. 2, a smartphone device (which can also obtain impedance measurements similar to a wearable wristwatch) includes a multi-functional touch screen surface that supports user input to the smartphone device.

[0095] In some embodiments, the mobile device is a watch. For example, in Figure 3, the mobile device is a wearable watch. In other embodiments, the mobile device is a smartphone device. For example, in Figure 2, the mobile device is a smartphone device.

[0096] In some embodiments, block 910 may be performed by a first device and block 920 may be performed by a second device. That is, the impedance measurement may be performed by a device separate from the generation of the hydration level measurement. For example, the impedance measurement may be performed via a communication device worn by the user, while the generation of the hydration level may be performed by a server computer that receives the impedance indication from the communication device. In some embodiments, the server computer may reside in a cloud system.

[0097] FIG. 10 illustrates an example of a computing system that may implement one or more embodiments. The computer system illustrated in FIG. 10 may be incorporated as a portion of the computerized device described above. For example, the computer system 1000 may represent some of the components of a television, a computing device, a server, a desktop, a workstation, a control or interaction system in an automobile, a tablet, a netbook, or any other suitable computing system. The computing device may be any computing device that includes an image capture device or an input sensing unit and a user output device. The image capture device or the input sensing unit may be a camera device. The user output device may be a display unit. Examples of computing devices include, but are not limited to, a video game console, a tablet, a smartphone, and any other handheld device. FIG. 10 provides a schematic diagram of one embodiment of a computer system 1000 that may perform methods provided by various other embodiments as described herein and / or function as a host computer system, a remote kiosk / terminal, a point of sale device, a telephone interface or a navigation interface or a multimedia interface in an automobile, a computing device, a set-top box, a table computer, and / or a computer system. FIG. 10 is intended only to provide a generalized view of the various components, any or all of which may be utilized as desired. Thus, FIG. 10 broadly illustrates how individual system elements may be implemented relatively separately or relatively integrated. In some embodiments, elements of computer system 100 may be used to implement the functionality of the mobile device of FIG.

[0098] A computer system 1000 is shown comprising hardware elements that may be electrically coupled (or may communicate in other suitable manner) via a bus 1002. The hardware elements may include one or more processors 1004, including but not limited to one or more general purpose processors and / or one or more special purpose processors (digital signal processing chips, graphics acceleration processors, etc.), one or more input devices 1008, which may include but are not limited to one or more cameras, sensors, mice, keyboards, microphones configured to detect ultrasound or other sound waves, etc., and one or more output devices 1010, which may include but are not limited to display units, printers, etc., such as devices used in embodiments of the present invention.

[0099] In some implementations of embodiments of the present invention, the various input devices 1008 and output devices 1010 may be embedded in interfaces such as display devices, tables, floors, walls, window screens, etc. Furthermore, the input devices 1008 and output devices 1010 coupled to a processor may form a multi-dimensional tracking system.

[0100] Computer system 1000 may further include (and / or be in communication with) one or more non-transitory storage devices 1006, which may comprise, but are not limited to, local and / or network accessible storage devices and / or may include, but are not limited to, solid-state storage devices such as disk drives, drive arrays, optical storage devices, random access memory ("RAM") and / or read-only memory ("ROM"), which may be programmable, flash updatable, etc. Such storage devices may be configured to implement any suitable data storage, including, but not limited to, various file systems, database structures, etc.

[0101] The computer system 1000 may also include a communication subsystem 1012, which may include, but is not limited to, a modem, a network card (wireless or wired), an infrared communication device, a wireless communication device, and / or a chipset (Bluetooth device, 802.11 device, WiFi device, WiMax device, cellular communication equipment, etc.). The communication subsystem 1012 may enable data to be exchanged with a network, other computer systems, and / or any other device described herein. In many embodiments, the computer system 1000 will further comprise a non-transitory working memory 1018, which may include a RAM or ROM device, as described above.

[0102] Computer system 1000 may also comprise software elements, currently shown as residing in working memory 1018, including other code, such as an operating system 1014, device drivers, executable libraries, and / or one or more application programs 1016, which may comprise computer programs provided by various embodiments and / or may be designed to implement methods and / or configure systems provided by other embodiments as described herein. By way of example only, one or more procedures described in connection with the methods discussed above may be embodied as code and / or instructions executable by a computer (and / or a processor within a computer), and in one aspect, such code and / or instructions may then be used to configure and / or adapt a general-purpose computer (or other device) to perform one or more operations in accordance with the methods described.

[0103] A set of these instructions and / or code may be stored on a computer-readable storage medium, such as storage device 1006 described above. In some cases, the storage medium may be incorporated within a computer system, such as computer system 1000. In other embodiments, the storage medium may be separate from the computer system (e.g., a removable medium such as a compact disc) and / or provided in an installation package, such that it may be used to program, configure, and / or adapt a general-purpose computer with the instructions / code stored thereon. These instructions may take the form of executable code that is executable by computer system 1000 and / or may take the form of source code and / or installable code that takes the form of executable code when compiled and / or installed on computer system 1000 (e.g., using any of a variety of commonly available compilers, installation programs, compression / decompression utilities, etc.).

[0104] Substantial variations can be made according to specific requirements. For example, customized hardware can also be used and / or certain elements can be implemented in hardware, software (including portable software such as applets), or both. Additionally, connection to other computing devices, such as network input / output devices, can also be used. In some embodiments, one or more elements of computer system 1000 can be omitted or implemented separately from the illustrated system. For example, processor 1004 and / or other elements can be implemented separately from input device 1008. In one embodiment, the processor is configured to receive images from one or more cameras that are implemented separately. In some embodiments, elements in addition to those illustrated in FIG. 10 can be included in computer system 1000.

[0105] Some embodiments may employ a computer system (such as computer system 1000) to perform methods according to the present disclosure. For example, some or all of the steps of the described methods may be performed by computer system 1000 in response to processor 1004 executing one or more sequences of one or more instructions (which may be embedded in other code, such as operating system 1014 and / or application program 1016) contained in working memory 1018. Such instructions may be read into working memory 1018 from another computer-readable medium, such as one or more of storage devices 1006. By way of example only, execution of a sequence of instructions contained in working memory 1018 may cause processor 1004 to perform one or more steps of the methods described herein.

[0106] As used herein, the terms "machine-readable medium" and "computer-readable medium" refer to any medium involved in providing data that causes a machine to operate in a specific manner. In some embodiments implemented using computer system 1000, various computer-readable media may be involved in providing instructions / code to processor 1004 for execution and / or may be used to store and / or carry such instructions / code (e.g., as a signal). In many implementations, computer-readable media are physical and / or tangible storage media. Such media can take many forms, including, but not limited to, non-volatile media, volatile media, and transmission media. Non-volatile media include, for example, optical and / or magnetic disks, such as storage device 1006. Volatile media include, but are not limited to, dynamic memory, such as working memory 1018. Transmission media include, but are not limited to, coaxial cables, copper wire, and fiber optics, including the wires that comprise bus 1002 and various components of communication subsystem 1012 (and / or the medium through which communication subsystem 1012 provides communication with other devices). Accordingly, transmission media may also take the form of waves (including but not limited to radio waves, sound waves, and / or light waves, such as those generated during radio wave and infrared data communications).

[0107] Common forms of physical and / or tangible computer readable media include, for example, a floppy disk, a flexible disk, a hard disk, a magnetic tape or any other magnetic medium, a CD-ROM, any other optical medium, punch cards, paper tape, any other physical medium with a pattern of holes, RAM, PROM, EPROM, Flash EPROM, any other memory chip or cartridge, a carrier wave as described below, or any other medium from which a computer can read instructions and / or code.

[0108] Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processor 1004 for execution. By way of example only, the instructions may initially be carried on a magnetic and / or optical disk of a remote computer. The remote computer may load the instructions into its dynamic memory and transmit the instructions as signals over a transmission medium to be received and / or executed by the computer system 1000. These signals, which may take the form of electromagnetic, acoustic, optical, etc., are all examples of carrier waves on which instructions may be encoded, according to various embodiments of the present invention.

[0109] The communications subsystem 1012 (and / or components thereof) typically receives signals, after which the bus 1002 can convey the signals (and / or data, instructions, etc. carried by the signals) to the working memory 1018, from which the processor 1004 retrieves and executes the instructions. The instructions received by the working memory 1018 can optionally be stored on the non-transitory storage device 1006 either before or after execution by the processor 1004.

[0110] The methods, systems, and devices discussed above are examples. Various configurations may omit, substitute, or add various procedures or components, as appropriate. For example, in alternative configurations, the methods may be performed in a different order than described, and / or various steps may be added, omitted, and / or combined. Also, features described in connection with a particular configuration may be combined in various other configurations. Different aspects and elements of the configurations may be combined in a similar manner. Also, technology evolves over time, and therefore many of the elements are examples and do not limit the scope of the disclosure or the claims.

[0111] Specific details are given in the description to provide a thorough understanding of the exemplary configurations (including implementations). However, the configurations can be practiced without these specific details. For example, well-known circuits, processes, algorithms, structures, and techniques are shown without unnecessary detail to avoid obscuring the configurations. This description provides only exemplary configurations and does not limit the scope, applicability, or configurations of the claims. Rather, the preceding description of the configurations will provide those skilled in the art with a description that will be helpful in implementing the described techniques. Various changes can be made in the function and arrangement of elements without departing from the spirit or scope of the present disclosure.

[0112] Also, the configurations may be described as processes that are depicted as flow charts or block diagrams. Although each may describe operations as a sequential process, many of the operations may be performed in parallel or simultaneously. Additionally, the order of operations may be rearranged. A process may have additional steps not included in the diagrams. Additionally, the example methods may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware, or microcode, the program code or code segments to perform the necessary tasks may be stored in a non-transitory computer-readable medium, such as a storage medium. A process may perform the tasks described.

[0113] While several example configurations have been described, various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the disclosure. For example, the above elements may be components of a larger system in which other rules may take precedence or which may otherwise modify the application of the invention. Also, some steps may be taken before, during, or after consideration of the above elements. [Explanation of symbols]

[0114] 100 Mobile Devices 110 Processor 120 Microphones 130 Display 140 Input Devices 150 Speaker 160 Memory 162 Module 1 164 Module 2 170 Camera 180 Sensors 182 Optical Sensor 184 Electrode 185 Light source 190 Computer-readable medium 192 PPG measurement module 194 ECG measurement module 196 Blood Pressure Measurement Module 198 Impedance Measurement Module 199 Hydration Level Measurement Module 210 Smartphone Devices 220 Contact 230 Second move 240 First move 250 Device Front 260 users 310 Wristwatch Device 320 Multifunction Button 410 Cross Section 412 Photodetector 414 Light Emitting Diode (LED) 416 Electrode Contact 418 Radius 419 Ulna 420 Graph 430 Graph 440 Graphs 460 Contact Button 470 PPG sensor 480 ECG Signal 490 PPG signal 500 Schematic 510 User's Body 520 Impedance Converter 700 Flow Chart 710 Sensor Measurement Standards 720 Derived Metrics 800 Flow Chart 900 Flow Chart 1000 Computer Systems 1002 Bus 1004 Processor 1006 Storage Devices 1008 Input Devices 1010 Output Device 1012 Communication Subsystem 1014 Operating Systems 1016 Application Program 1018 Working Memory

Claims

1. 1. A wearable device comprising: An exterior body formed as part of a wristwatch and configured to be wearable on a user's wrist; a first sensor disposed in contact with the user when the wearable device is in use by the user, the first sensor configured to transmit a first sensor signal; a second sensor including a plurality of electrodes, the second sensor being arranged such that at least one electrode of the plurality of electrodes contacts the user when the wearable device is in use by the user, the second sensor being configured to receive a second sensor signal; a multifunction surface or button configured to detect one or more user interactions, the multifunction surface or button being configured with one or more electrodes of the second sensor; A processor coupled to the first and second sensors, the processor comprising: receiving a user input indicating a desire to obtain one or more physical function measures; transitioning from normal operation to a measurement mode in response to receiving the user input indicating the request to obtain the one or more body function measurements, wherein during normal operation of operating the multifunction surface or multifunction button, the wearable device is configured to obtain body measurements based on the second sensor signal, and during the measurement mode, the wearable device is configured to determine one or more body function measurements based on the first sensor signal, measurements based on at least the second sensor signal, or a combination thereof, the one or more body function measurements comprising the user's stress level, the user's blood pressure, the user's blood volume, the user's hydration level, the user's cardiac electrical activity, the user's blood oxygen content, or a combination thereof; 23. A wearable device configured to:

2. The wearable device of claim 1 , wherein the first sensor signal is indicative of the blood volume of the user and the second sensor signal is indicative of the electrical activity of the user's heart.

3. The wearable device of claim 2 , wherein the first sensor includes one or more light sources and one or more light sensors.

4. The wearable device of claim 1 , wherein the second sensor signal is indicative of the hydration level of the user.

5. 2. The wearable device of claim 1, wherein a first electrode of at least two electrodes of the plurality of electrodes is disposed on one end of the wearable device and a second electrode of the at least two electrodes is disposed on an opposite end of the wearable device.

6. 2. The wearable device of claim 1, wherein a first electrode of at least two electrodes of the plurality of electrodes is disposed on a surface of the wearable device configured to be worn against the skin of the user, and a second electrode of the at least two electrodes is disposed on the multi-functional surface.

7. The wearable device of claim 1 , wherein the processor is configured to determine the one or more physical function measures based on a pulse transit time (PTT) technique.

8. The processor, determining a photoplethysmography (PPG) measurement based on the first sensor signal; determining an electrocardiography (ECG) measurement based on the second sensor signal; determining a PTT using said PTT technique based on said PPG measurements and said ECG measurements; [0023] The device is further configured to: The one or more physical function measures are based on the PTT.

8. The wearable device of claim 7.

9. 2. The wearable device of claim 1, wherein the one or more physical function measurements include a stress level of the user, and the processor is further configured to output a notification indicating that the user should take a deep breath based on the stress level.

10. 1. A method for obtaining at least one physical function measure, comprising: receiving a user input indicating a request to obtain one physical function measurement from a wearable device, the wearable device comprising: An exterior body formed as part of a wristwatch and configured to be wearable on a user's wrist; a first sensor disposed in contact with the user when the wearable device is in use by the user, the first sensor configured to transmit a first sensor signal; a second sensor including a plurality of electrodes, the second sensor being arranged such that at least one electrode of the plurality of electrodes contacts the user when the wearable device is in use by the user, the second sensor being configured to receive a second sensor signal; a multifunction surface or button configured to detect one or more user interactions, the multifunction surface or button being configured with one or more electrodes of the second sensor; the receiving step including: transitioning, by a processor, from normal operation of the wearable device to a measurement mode in response to receiving the user input indicating the request to obtain the one or more body function measurements, wherein the wearable device is configured to obtain body measurements based on the second sensor signal during normal operation of manipulating the multi-function surface or a multi-function button; receiving, in the measurement mode by the processor, the first sensor signal, a measurement based on the second sensor signal, or a combination thereof; determining, in the measurement mode by the processor, one or more physical function measures based on the first sensor signal, measurements based on at least the second sensor signal, or a combination thereof, wherein the one or more physical function measures comprise the user's stress level, the user's blood pressure, the user's blood volume, the user's hydration level, the user's cardiac electrical activity, the user's blood oxygen content, or a combination thereof; A method comprising:

11. The method of claim 10 , wherein the first sensor signal is indicative of the blood volume of the user and the second sensor signal is indicative of the electrical activity of the heart of the user.

12. The method of claim 11 , wherein the first sensor includes one or more light sources and one or more light sensors.

13. The method of claim 10 , wherein the second sensor signal is indicative of the hydration level of the user.

14. 11. The method of claim 10, wherein a first electrode of at least two electrodes of the plurality of electrodes is disposed on one end of the wearable device and a second electrode of the at least two electrodes is disposed on an opposite end of the wearable device.

15. 11. The method of claim 10, wherein a first electrode of at least two electrodes of the plurality of electrodes is disposed on a surface of the wearable device configured to be worn against the skin of the user, and a second electrode of the at least two electrodes is disposed on the multi-functional surface.

16. 11. The method of claim 10, wherein determining the one or more physical function measures is based on a pulse transit time (PTT) technique.

17. The method comprises: determining a photoplethysmography (PPG) measurement based on the first sensor signal; determining an electrocardiography (ECG) measurement based on the second sensor signal; determining a PTT using the PTT technique based on the PPG measurements and the ECG measurements. Further comprising: The one or more physical function measures are based on the PTT. The method of claim 16.

18. the one or more physical function measures including a stress level of the user, and outputting a notification indicating that the user should take a deep breath based on the stress level.

11. The method of claim 10, further comprising:

19. A computer readable storage medium comprising instructions executable by a processor configured to cause the processor to perform a method according to any one of claims 10 to 18.

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