PATENT DOCUMENT

Publication Number: US-10512432-B2
Application Number: US-201715675478-A
Country: US
Kind Code: B2

Title: Vital signs monitoring system

Abstract:
This relates to a monitoring system capable of measuring a plurality of vital signs. The monitoring system can include a plurality of sensors including, but not limited to, electrodes, piezoelectric sensors, temperature sensors, and accelerometers. The monitoring system can be capable of operating in one or more operation modes such as, for example: capacitance measurement mode, electrical measurement mode, piezoelectric measurement mode, temperature measurement mode, acceleration measurement mode, impedance measurement mode, and standby mode. Based on the measured values, the monitoring system can analyze the user&#39;s sleep, provide feedback and suggestions to the user, and/or can adjust or control the environmental conditions to improve the user&#39;s sleep. The monitoring system can further be capable of analyzing the sleep of the user(s) without directly contacting or attaching uncomfortable probes to the user(s) and without having to analyze the sleep in an unknown environment (e.g., a medical facility).

Claims:
What is claimed is: 
     
       1. A system for determining one or more physiological signals of a user, the system comprising:
 one or more first electrodes configured to:
 measure one or more electrical signals of the user; 
 
 one or more second electrodes configured to capacitively couple to the one or more first electrodes; and 
 logic configured to:
 generate one or more first signals indicative of a first plurality of changes in capacitive coupling, the first plurality of changes in capacitive coupling being between the one or more first electrodes and the one or more second electrodes; 
 determine one or more locations of the user based on the one or more first signals; 
 select a subset of the one or more first electrodes based on the determined one or more locations of the user; 
 generate one or more second signals indicative of a second plurality of changes in capacitive coupling, the second plurality of changes in capacitive coupling being between the subset of the one or more first electrodes and the one or more second electrodes; 
 detect the one or more electrical signals of the user using the subset of the one or more first electrodes; 
 generate one or more third signals indicative of the detected one or more electrical signals of the user; and 
 determine one or more physiological signals based at least in part on the one or more second signals and the one or more third signals. 
 
 
     
     
       2. The system of  claim 1 , wherein the one or more first electrodes are located within a first portion of the system, and the one or more second electrodes are located within a second portion of the system, the second portion is at least partially physically separated from the first portion. 
     
     
       3. The system of  claim 2 , wherein the first portion is included in a sheet, and the second portion is included in a blanket. 
     
     
       4. The system of  claim 1 , further comprising:
 one or more switches configured to electrically couple at least two of the one or more first electrodes together or at least two of the one or more second electrodes together, 
 wherein the logic is further configured to associate a decrease in each of the second plurality of changes in capacitive coupling to an increase in gap due to a body of the user physically separating the one or more first electrodes from the one or more second electrodes. 
 
     
     
       5. The system of  claim 1 , further comprising:
 a first section with a first granularity; 
 a second section with a second granularity capable of being different from the first granularity; and 
 one or more switches configured to couple or decouple the one or more first electrodes together, the one or more second electrodes together, or both to dynamically change one or more of the first and second granularities. 
 
     
     
       6. The system of  claim 1 , wherein the one or more first electrodes are configured to capacitive couple to the user. 
     
     
       7. The system of  claim 1 , further comprising:
 a plurality of temperature sensors configured to measure temperature, wherein the plurality of temperature sensors includes a first set of temperature sensors and a second set of temperature sensors, the first set of temperature sensors are located in a first region underneath the user when laying on the system, and the second set of temperature sensors are located in a second region. 
 
     
     
       8. The system of  claim 7 , wherein the logic is further configured to generate a temperature image from signals from the first set of temperature sensors and from signals from the second set of temperature sensors. 
     
     
       9. The system of  claim 8 , wherein the logic is further configured to determine a location of the user&#39;s body based on the temperature image. 
     
     
       10. The system of  claim 1 , further comprising:
 one or more accelerometers configured to measure acceleration, vibrations, or both. 
 
     
     
       11. The system of  claim 10 , wherein the one or more accelerometers are located on a same layer as the one or more first electrodes. 
     
     
       12. The system of  claim 1 , wherein the one or more first electrodes are located on a first layer, and the one or more second electrodes are located on a second layer. 
     
     
       13. The system of  claim 1 , further comprising:
 one or more piezoelectric sensors configured to generate one or more fourth signals, wherein the logic is configured to determine the one or more physiological signals further based on the one or more fourth signals. 
 
     
     
       14. The system of  claim 13 , wherein the one or more piezoelectric sensors are interleaved with one or more rows of the one or more first electrodes, the one or more second electrodes, or both. 
     
     
       15. The system of  claim 14 , wherein the one or more piezoelectric sensors include one or more sections of rigid material physically connected with flexible material. 
     
     
       16. The system of  claim 14 , further comprising:
 one or more switches configured to electrically couple at least two of the one or more piezoelectric sensors together. 
 
     
     
       17. The system of  claim 13 , wherein the one or more piezoelectric sensors include a first one or more piezoelectric sensors and a second one or more piezoelectric sensors,
 wherein the first one or more piezoelectric sensors are electrically isolated from and capable of taking independent measurements from the second one or more piezoelectric sensors. 
 
     
     
       18. The system of  claim 13 , wherein the one or more first electrodes are disposed on the one or more piezoelectric sensors. 
     
     
       19. The system of  claim 18 , wherein the one or more first electrodes are located in every other row, and the one or more second electrodes are located in others of the every other row of the one or more first electrodes.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 62/374,615, filed Aug. 12, 2016, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     This relates generally to monitoring systems and methods for measuring vital signs of one or more users. 
     BACKGROUND 
     Traditionally, monitoring a person&#39;s sleep or vital signs has required expensive and bulky equipment. Some systems require that the monitoring be performed away from home in a medical facility and/or require the equipment to attach to or directly contact the person, which can lead to discomfort and can lead to inaccurate analysis due to disruption of the person&#39;s sleep. Furthermore, these systems are configured to determine the vital signs based on one type of measurement or mode of operation. Moreover, these systems are configured for monitoring only a single person; these systems lack the capability of not only monitoring multiple users, but also incorporating the analysis of a first user into the analysis of a second user, whose sleep may be affected by the first user. 
     SUMMARY 
     This relates to a monitoring system capable of measuring a plurality of vital signs for one or more users. The monitoring system can include a plurality of sensors including, but not limited to, electrodes, piezoelectric sensors, temperature sensors, and accelerometers. The monitoring system can be capable of operating in one or more operation modes such as, for example: capacitance measurement mode, electrical measurement mode, piezoelectric measurement mode, temperature measurement mode, acceleration measurement mode, impedance measurement mode, and standby mode. Based on the measured values, the monitoring system can perform functions such as analyze the user&#39;s sleep, provide feedback and suggestions to the user, and/or can adjust or control the environmental conditions to improve the user&#39;s sleep. The monitoring system can be further capable of dynamically partitioning the system into multiple sections to account for multiple users. Each section can be tailored to the corresponding user with independent control and independent measurements to provide separate sleep analysis unique to the user. The monitoring system can utilize the information from one user in its assessment of the sleep of another user. The monitoring system can be utilized at home or can be portable, giving the user flexibility with locations where the monitoring system can be used. The monitoring system can further be capable of analyzing the sleep of the user(s) without directly contacting or attaching uncomfortable probes to the user(s) and without having to analyze the sleep in an unknown environment (e.g., a medical facility). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exemplary block diagram of the monitoring system according to examples of the disclosure. 
         FIGS. 2A-2B  illustrate top and perspective views of layers included in an exemplary mat according to examples of the disclosure. 
         FIGS. 2C-2F  illustrate cross-sectional views of an exemplary mat according to examples of the disclosure. 
         FIG. 2G  illustrates an exemplary process flow for capacitive measurements according to examples of the disclosure. 
         FIG. 2H  illustrates an exemplary perspective view of layers included in an exemplary mat according to examples of the disclosure. 
         FIG. 3A  illustrates a cross-sectional view of an exemplary monitoring system including a mat according to examples of the disclosure. 
         FIGS. 3B-3C  illustrate cross-sectional views of exemplary mats according to examples of the disclosure. 
         FIGS. 3D-1 and 3D-2  illustrate an exemplary process flow for dynamically switching one or more electrodes utilized for capacitance measurements according to examples of the disclosure. 
         FIG. 3E  illustrates a cross-sectional view of an exemplary mat including a switching matrix according to examples of the disclosure. 
         FIGS. 4A-4C  illustrate top, perspective, and cross-sectional views of layers included in an exemplary mat according to examples of the disclosure. 
         FIGS. 4D-1 and 4D-2  illustrate an exemplary process flow for capacitive and electrical measurements according to examples of the disclosure. 
         FIG. 4E  illustrates a cross-sectional view of an exemplary mat according to examples of the disclosure. 
         FIG. 4F  illustrates a cross-sectional view of an exemplary mat according to examples of the disclosure. 
         FIG. 5A  illustrates a top view of an exemplary monitoring system including multiple sections according to examples of the disclosure. 
         FIGS. 5B-1 to 5B-3  illustrate an exemplary process flow for dynamically partitioning the mat into multiple sections according to examples of the disclosure. 
         FIG. 5C  illustrates a top view of an exemplary monitoring system including multiple sections according to examples of the disclosure. 
         FIGS. 6A-6B  illustrate top and perspective views of layers included in an exemplary mat according to examples of the disclosure. 
         FIGS. 6C-6D  illustrate cross-sectional views of an exemplary mat according to examples of the disclosure. 
         FIGS. 6E-1 and 6E-2  illustrate an exemplary process flow for capacitive, electrical, and piezoelectric measurements according to examples of the disclosure. 
         FIGS. 7A-7B  illustrate top views of exemplary layers included in a mat according to examples of the disclosure. 
         FIGS. 7C-7D  illustrate top and cross-sectional views of an exemplary mat including electrodes disposed on piezoelectric sensors according to examples of the disclosure. 
         FIGS. 7E-7G  illustrate cross-sectional views of exemplary mats according to examples of the disclosure. 
         FIG. 8A  illustrates a top view of an exemplary layer of a mat including a plurality of electrodes, a plurality of piezoelectric sensors, and a plurality of temperature sensors according to examples of the disclosure. 
         FIGS. 8B-8C  illustrate cross-sectional and top views of the monitoring system including temperature sensors according to examples of the disclosure. 
         FIG. 8D  illustrates an exemplary process flow for temperature measurements according to examples of the disclosure. 
         FIG. 9  illustrates a top view of an exemplary layer of a mat including a plurality of electrodes, a plurality of piezoelectric sensors, a plurality of temperature sensors, and a plurality of accelerometers according to examples of the disclosure. 
         FIG. 10A  illustrates a top view of an exemplary layer included in a mat configured for ICG measurements according to examples of the disclosure. 
         FIG. 10B  illustrates a corresponding circuit diagram according to examples of the disclosure. 
         FIG. 10C  illustrates an exemplary process flow configured for impedance measurement according to examples of the disclosure. 
         FIGS. 11A-11C  illustrate measurement modes over time for a monitoring system according to examples of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description of examples, reference is made to the accompanying drawings in which it is shown by way of illustration specific examples that can be practiced. It is to be understood that other examples can be used and structural changes can be made without departing from the scope of the various examples. 
       FIG. 1  illustrates an exemplary block diagram of the monitoring system according to examples of the disclosure. System  199  can include mat  102 , power source  103 , camera  108 , and control system  140 . Mat  102  can be resting on, attached to, or in contact with a bed (not shown) or any type of apparatus configured to support one or more human users, one or more pets, or the like. Mat  102  can be configured to cover all or a portion of a mattress, for example, that can be resting, attached to, or supported by one or more frames of the bed. In some examples, mat  102  can be flexible. In some examples, mat  102  can be at least partially rigid. Mat  102  can include one or more of a sheet, blanket, duvet, pillow or pillowcase, or insert. Mat  102  can be a stand-alone unit that can be placed on a bed or can be incorporated into the fabric or textile used as part of a sleeping/resting arrangement. 
     Power source  102  can be configured to provide power to system  199 . In some examples, the power source can be configured to couple to a power outlet. In some examples, the power source can be coupled to a battery and a charging station or power supply. In some examples, the power source can be configured to receive power from a charging element, such as a magnetic puck. In some examples, the charging element can include an inductive coil, and power can be transferred to the monitoring system via an electromagnetic field. 
     System  199  can include camera  108  and control system  140 . Camera  108  can be a video camera configured to perform one or more functionalities, including, but not limited to, determining the position of the user&#39;s body, determining the location of the user&#39;s body, determining the temperature of the user&#39;s body, and determining the temperature of the local ambient. The monitoring system can be configured to utilize the information from camera  108  in conjunction with the information from the one or more sensors (e.g., electrodes  182 , piezoelectric sensors  134 , temperature sensors  138 , accelerometers  142 , and electrical sensors  182 ) for sleep analysis and feedback. 
     Control system  140  can be configured to control one or more parameters. For example, control system  140  can include temperature sensors  139 , which can measure and provide information to the control system about the room temperature. In some examples, control system  140  can be configured to communicate with mat  102  through wired (e.g., using a cable) or wireless communications. Control panel  140  can include a touch panel and/or a display and can be configured to interface with the user and/or a computer. For example, control panel  140  can display heart rate, heart rate variability, respiratory rate, respiratory rate variability, user&#39;s motion, and user&#39;s temperature. In some examples, control panel  140  can display analysis regarding the user&#39;s sleep and/or can provide suggestions to improve the user&#39;s sleep. 
     Mat  102  can include one or more electrodes  182 , one or more piezoelectric sensors  134 , plurality of temperature sensors  138 , and one or more accelerometers  142 . The electrodes and sensors included in system  199  can include one or more functionalities and configurations discussed below. System  199  can include a controller configured to determine one or more measurements, such as BCG measurement  123 , ECG measurement  183 , acceleration measurement  143 , temperature measurement  139 , and ICG measurement  133 . Although  FIG. 1  illustrates mat  102  as including four different types of sensors, examples of the disclosure can include a monitoring system that includes one or more of the different types of sensors. 
     While control system  140  can be included in system  199 , examples of the disclosure can include an arrangement where control system  140  is separate and distinct from system  199 . System  199  can be communicate information (e.g., temperature measurement, acceleration measurement, ICG measurement, ECG measurement, and BCG measurement) to control system  140  through wired or wireless (e.g., local area network) communication means. In some examples, control system  140  can include a transceiver to receive the information from system  199  and a controller or processor to process the information for the analysis (e.g., to determine heart rate, heart rate variability, respiratory rate, and respiratory rate variability). 
       FIGS. 2A-2B  illustrate top and perspective views of layers included in an exemplary mat according to examples of the disclosure. The exemplary mat can include layer  220  and layer  230 . Layer  220  can include electrode  222 . “Electrodes,” referred to herein, can be a conductive unit individually connected for driving or sensing purposes. In some examples, electrode  222  can be configured to cover a substantial (e.g., more than 75%) area of layer  222  and can be continuous (i.e., a discrete piece of material). Layer  230  can include a plurality of electrodes  232 . Electrode  222 , plurality of electrodes  232 , or both can include any conductive material including, but not limited to, silver, copper, gold, aluminum, steel, brass, bronze, and graphite. In some examples, electrode  222  and plurality of electrodes  232  can include the same materials. In some examples, the exemplary mat can include layer  240 . Layer  240  can be configured to provide support or electrical insulation from one or more materials or layers (e.g., the mattress), for example. In some examples, layer  240  can include one or more electrodes (not shown). Although  FIGS. 2A-2B  illustrate layer  220  as including one electrode and layer  230  as including a plurality of electrodes, each layer can include any number of electrodes. 
       FIGS. 2C-2F  illustrate cross-sectional views of an exemplary mat according to examples of the disclosure. The exemplary mat can be configured with any numbers of layers and/or arrangement of the layers relative to the other layers. For example, as illustrated in  FIG. 2C , layer  220  can be located on one side of layer  230 , and layer  240  can be located on the other side of layer  230 . Electrode  222  disposed on layer  220  can be located on the side opposite of layer  220  than user  298 . Electrode  232  can be located between layer  230  and layer  240 . Electrode  242  can be located on the side of layer  240  opposite electrode  232 . 
     In some examples, as illustrated in  FIG. 2D , electrode  222  can be located on one side of layer  220  closer to user  298  than layer  220 . Electrode  232  can be located on the opposite side of layer  220  than user  298  and between layer  220  and layer  230 . In some examples, as illustrated in  FIG. 2E , electrode  232  can be located closer to user  298  than electrode  222 . Electrode  232  can be disposed on layer  230 , and electrode  222  can be disposed on layer  220 . Layer  230  can be located closer to user  298  than electrode  232 . Additionally, the exemplary mat can include layer  240  located on the opposite side of electrode  222  than layer  220 . In some examples, as illustrated in  FIG. 2F , layer  220  and electrode  222  can be located closer to the user than layer  230  and electrode  232 . Although the figures illustrate one or more electrodes disposed on the corresponding layer, examples of the disclosure can include one or more electrodes embedded entirely or partially within the layer or disposed at least partially on the layer. Although the figures illustrate user  298  located on one side the exemplary mat, examples of the disclosure can include the exemplary mat being capable of functioning as a monitoring system regardless of the side user  298  is located. Furthermore, the exemplary monitoring system can be capable of functioning when user  298  is located in the center or edges of the mat. 
     Electrode  222 , electrode  232 , and/or electrode  242  can be configured with one or more functionalities. For example, electrode  222  and electrode  232  can be configured to measure a plurality of capacitance values. Electrode  222  can be configured as a sense electrode, and the plurality of electrodes  232  can be configured as drive electrodes. In some examples, electrode  222  can be configured as a drive electrode, and the plurality of electrodes  232  can be configured as sense electrodes. When an external force is applied, e.g., by the body weight of user  298 , electrode  222  can move closer to electrode  232 , which in turn, can cause a change (e.g., increase) in the mutual capacitance between the electrodes (i.e., sense and drive electrodes). In some examples, electrodes included in the plurality of electrodes  232  can be stimulated one at a time, and the capacitance associated with the stimulated electrode  222  can be measured by sense circuitry. In some examples, electrode  222  can include one or more sections of conductive material electrically coupled together. In some examples, the change in capacitance can be related to the distance between electrode  232  and electrode  222 . One or more images of the strength or intensity of force applied by user  298  can be obtained based on the changes in capacitance. 
     In some examples, capacitance sensing can include measuring the capacitance at electrode  222 , plurality of electrodes  232 , or both relative to some reference, such as ground or a ground plane. The capacitance relative to the reference ground can be changed due to at least in part the presence of the user&#39;s body. In some examples, sensing can include resistive sensing, where the user&#39;s force or body weight can cause the electrodes to electrically contact. The electrodes can be driven and can cause conductive paths; electrically contacting the electrodes can cause a change in resistance (that can be measured as a change in current). 
     In some examples, electrode  242  (illustrated in  FIG. 2C ) can be configured as a shielding layer to shield the monitoring system from ambient noise. In some examples, electrode  242  can be coupled to drive circuitry, and drive circuitry can drive electrode  242  to a given voltage. In some examples, electrode  242  can be coupled to ground. Although electrode  242  and layer  240  are not illustrated in  FIGS. 2D-2F , examples of the disclosure can include any number of substrates and any number of layers configured for shielding. 
     The capacitance measurements can be used for detecting the position, location, and/or movement of the body of the user on the mat.  FIG. 2G  illustrates an exemplary process flow for capacitive measurements according to examples of the disclosure. Drive circuitry can stimulate one or more drive electrodes, creating a mutual capacitance with one or more sense electrodes (step  252  of process  250 ). Sense circuitry can be coupled to one or more sense electrodes. Sense circuitry can measure any changes in capacitance at the sense electrodes, where the changes in capacitance can be due to the user&#39;s force or body weight changing the distance between the electrodes (step  254  of process  250 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s position and/or location on the mat (step  256  of process  250 ). The controller or processor can determine which drive and/or sense electrodes are not affected by the user&#39;s force or body weight (step  258  of process  250 ). When the capacitance measurements are below a pre-determined threshold, the controller can disable or disconnect the drive and/or sense electrodes to conserve power, for example (step  260  of process  250 ). The measured capacitance values can be used to form at least a portion of a ballistocardiography (BCG) measurement (step  262  of process  250 ). In some examples, the measured capacitance values can be used to measure displacement of the user&#39;s body. The process can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  264  of process  250 ). 
     The BCG measurement, taken in step  262  of process  250 , can include changes in electrodes properties due to fine body movement (e.g., caused by the flow of the user&#39;s blood with each heartbeat). As blood is being pumped, the user&#39;s body can move back and forth (e.g., in a longitudinal direction), and this back and forth movement can be measured by recording or monitoring the changes in capacitance over time. In some examples, the monitoring system can be configured such that measurements from the electrodes located in the immediate periphery (i.e., adjacent to the electrodes located directly under the body of the user) of the user are included in the BCG measurement; since electrodes located in the immediate periphery can be more sensitive to body movement than the electrodes located directly underneath the user&#39;s body (e.g., where measurements can be influenced by gross motion). The BCG measurement can be used at least partially to measure the heart rate, heart rate variability, respiratory rate, and/or respiratory rate variability. 
     In some examples, the mat can include one or more dummy sections.  FIG. 2H  illustrates an exemplary perspective view of layers included in an exemplary mat according to examples of the disclosure. In some examples, layer  220  can include one or more dummy sections  224 . Dummy sections  224  can be configured to prevent neighboring electrodes from capacitively coupling to each other. In some examples, dummy sections  224  can be floating. In some examples, dummy sections  224  can be coupled to ground or drive circuitry. In some examples, layer  230  can, additionally or alternatively, include dummy sections (not shown). 
     In some examples, the layers included in the mat can be spatially separated.  FIG. 3A  illustrates a cross-sectional view of an exemplary monitoring system including a mat according to examples of the disclosure. System  399  can include sub-mat  302  and sub-mat  304 . In some examples, user  398  can be located between sub-mat  302  and sub-mat  304 . Sub-mat  302  and sub-mat  304  can be configured with any number of layers and/or arrangement of the layers relative to the other layers. For example, sub-mat  302  can include layer  320  and electrode  322 . Although the figure illustrates layer  320  located closer to user  398  than electrode  322  and layer  330  located closer to user  398  than electrode  332 , examples of the disclosure can include electrode  332  located closer to user  398  than layer  330 , electrode  322  located closer to user  398  than layer  320 , or both. The design and/or operation of layer  330 , plurality of electrodes  332 , and electrode  322  can include the design and/or operation of layer  230 , plurality of electrodes  232 , and electrode  222 , respectively, as discussed above. Sub-mat  304  can include layer  330  and plurality of electrodes  332 . 
     With user  398  located between sub-mat  302  and sub-mat  304 , one or more parts of user  398  can cause a change in the distance between plurality of electrodes  322  and electrode  332 . The change in distance between electrodes can be caused by physical properties (e.g., size) of the user&#39;s body parts and/or the user&#39;s position (e.g., the user can be laying on the user&#39;s side). For example, a lower mutual capacitance in one or more regions compared to other regions can be indicative of the presence of one or more user&#39;s body parts located between sub-mat  302  and sub-mat  304 . In some examples, system  399  can be configured to approximate the location of one or more user&#39;s body parts based on the capacitance value. For example, if the user is sleeping on his or her back (as illustrated in  FIG. 3A ), regions with lower mutual capacitance can be associated with body parts (e.g., arms or legs) having a lower profile. Regions with higher mutual capacitance can be associated with body parts (e.g., chest) having a higher profile. Alternatively, a lower mutual capacitance can be associated with the user lying on the user&#39;s back, and a higher mutual capacitance can be associated with the user lying on the user&#39;s side, for example. The capacitance measurements can include process  250  (illustrated in  FIG. 2G ) or self-capacitance measurements, discussed above. 
     In one or more regions where sub-mat  302  and sub-mat  304  can be contacting, electrode  322  can be in close proximity to electrode  332  and the mutual capacitance can be larger than in regions where sub-mat  302  and sub-mat  304  can be contacting. In some examples, plurality of electrodes  332  can be stimulated one at a time and the capacitance associated with the stimulated electrode  332  can be measured by circuitry coupled to electrode  322 . In some examples, electrode  322  can include one or more sections of conductive material electrically coupled together. 
       FIGS. 3B-3C  illustrate cross-sectional views of exemplary mats according to examples of the disclosure. In some examples, as illustrated in  FIG. 3C , system  399  can be configured with the plurality of electrodes  332  included in sub-mat  302  and electrode  322  included in sub-mat  304 . Although  FIG. 3C  illustrates layer  320  located closer to user  398  than electrode  322  and layer  330  located closer to user  398  than electrode  332 , examples of the disclosure can include plurality of electrodes  332  located closer to user  398  than layer  330 , electrode  322  located closer to user  398  than layer  320 , or both. 
     In some examples, sub-mat  302  can include a switching matrix  391 , as illustrated in  FIG. 3C . Sub-mat  302  can include a plurality of layers of electrodes, such as plurality of electrodes  332  disposed on layer  330  and plurality of electrodes  342  disposed on layer  340 . Switching matrix  391  can be configured to electrically couple one or more electrodes included in the plurality of electrodes  332  together. System  399  can be capable of dynamically switching one or more electrodes utilized for the capacitance measurements. For example, in a first mode, user  398  can be located between sub-mat  302  and sub-mat  304 . Electrode  322  can be configured as a sense electrode, and the plurality of electrodes  332  can be configured as drive electrodes. Changes in capacitance values can be due to the user&#39;s body parts increasing the separations between the sense and drive electrodes. In a second mode, sub-mat  304  can be removed from system  399  or located a certain distance away. The separation between sub-mat  304  from sub-mat  302  can prevent electrode  322  from capacitively coupling to plurality of electrodes  332 , or the measured capacitance values can be below a predetermined threshold. 
     Switching matrix  391  can electrically couple together the plurality of electrodes  332 . The electrically coupled electrodes  332  can be configured as a sense electrode, and the plurality of electrodes  342  can be configured as drive electrodes. Changes in capacitance values can be due to the user&#39;s body weight applying a force that can change the distance between the sense and drive electrodes. When sub-mat  304  is returned back to system  399  and located a close enough distance such that electrode  322  can capacitively couple to electrode  332  (or the measured capacitance values can become greater than the predetermined threshold), system  399  can either remain in the second mode or switch to the first mode. 
     In some examples, drive circuitry can drive two or more electrodes differently. For examples, one or more electrodes can be driven by the drive circuitry, whereas other electrodes may not. The system can switch which electrodes to capacitively couple. For example, in a first operation mode, the system can drive electrodes located in sub-mat  302  (or sub-mat  304 ) to capacitively couple with sense electrodes also located in sub-mat  302  (or sub-mat  304 ). In a second operation mode, the system can drive electrodes located in sub-mat  302  (or sub-mat  304 ) to capacitively couple with sense electrodes located in sub-mat  304  (or sub-mat  302 ). In some examples, the system can alternate (e.g., time multiplex) between the first and second operation modes. In some examples, the electrodes can be driven with different stimulation signals. 
       FIGS. 3D-1 and 3D-2  illustrate an exemplary process flow for dynamically switching one or more electrodes utilized for capacitance measurements according to examples of the disclosure. Drive circuitry can stimulate one or more drive electrodes included in the mat to create a capacitance with one or more sense electrodes (step  372  of process  370 ). Sense circuitry can be coupled to one or more sense electrodes. Sense circuitry can determine whether the drive electrodes can capacitively couple to the electrodes (step  374  of process  370 ). If there is capacitive coupling (or whether the measured capacitance values are greater than a predetermined threshold), the system can switch to the first mode of measuring capacitance values. Sense circuitry can measure any changes in capacitance caused by the user&#39;s body parts creating separations or changes in distances between the drive electrodes and the sense electrodes (step  376  of process  370 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s body position and/or location (step  378  of process  370 ). The image can comprise matrix of capacitance values. The controller or processor can determine which drive and/or sense electrodes are not affected by the presence of the user&#39;s body (e.g., creating separations or reducing the gap between drive and sense electrodes) (step  380  of process  370 ) and can disable or disconnect the drive and/or sense electrodes to conserve power, for example (step  382  of process  370 ). The measured capacitance values can be used to form at least a portion of a BCG measurement (step  384  of process  370 ). The process can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  386  of process  370 ). 
     If there is no capacitively coupling or if the measured capacitance values are below a pre-determined threshold (determined in step  374  of process  370 ), the system can switch to the second mode of measuring capacitance values. Sense circuitry can measure any changes in capacitance caused by the user&#39;s force changing the distance between the drive and sense electrodes (step  388  in process  370 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s body position and/location on the mat (step  390  of process  370 ). The controller or processor can determine which drive and/or sense electrodes are not affected by the user&#39;s force or body weight (step  392  of process  370 ) and can disable or disconnect the drive and/or sense electrodes to conserve power, for example (step  394  of process  370 ). The measured capacitance values can be used to form at least a portion of a BCG measurement (step  384  of process  370 ). The process can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  386  of process  370 ). Although  FIGS. 3D-1 and 3D-2  illustrate process  370  as including the determination of whether there is capacitively coupling between the electrodes in the sub-mats after or while stimulating the drive electrodes, examples of the disclosure can include this determination at any time. For example, the system can be configured to periodically determine whether there is capacitive coupling regardless of what step in the process the system is in. 
     In some examples, the sub-mat can be capable of being folded and can include a switching matrix to dynamically reconfigure the measurements for such a situation.  FIG. 3E  illustrates a cross-sectional view of an exemplary mat including a switching matrix according to examples of the disclosure. Sub-mat  304  can include layer  330 , plurality of electrodes  332 , and switching matrix  393 . In some examples, sub-mat  304  can be folded over such that user  398  can be located between top  303  of sub-mat  304  and bottom  305  of sub-mat  304 . Sub-mat  304  can be configured to measure the capacitance between the plurality of electrodes  332  located in top  303  of sub-mat  304  and the plurality of electrodes  332  located in bottom  305  of sub-mat  304 . Switching matrix  393  can be configured to couple together some of the plurality of electrodes  332  located in one portion (e.g., bottom  305 ) of sub-mat  304 . The electrically coupled electrodes located in the one portion (e.g., bottom  305 ) can form a mutual capacitance to one or more of the plurality of electrodes  332  located in another portion (e.g., top  303 ) of sub-mat  304 . 
     To determine whether sub-mat  304  is folded and/or located in close proximity to sub-mat  302 , a test scan can be performed. The test scan can include coupling one or more electrodes  332  (or electrodes included in sub-mat  302 ) to drive circuitry and coupling other electrodes (e.g., other electrodes  332 ) to sense circuitry. In some examples, the test can include multiple combinations of different electrodes coupled to drive circuitry and different electrodes coupled to sense circuitry. Based on the combination of drive electrodes and sense electrodes where a capacitance value is greater than a pre-determined threshold, the location and/or configuration of sub-mat  302  and sub-mat  304  can be determined. 
       FIGS. 4A-4C  illustrate top, perspective, and cross-sectional views of layers included in an exemplary mat according to examples of the disclosure. The exemplary mat can include layer  420 , layer  430 , and layer  440 . Layer  420  can include electrode  422 , and layer  430  can include a plurality of electrodes  432 . The design and/or operation of layer  420 , layer  430 , layer  440 , electrode  422 , and plurality of electrodes  432  can include the design and/or operation of layer  220 , layer  230 , layer  240 , electrode  222 , and plurality of electrodes  232 , respectively, as discussed above. 
     In some examples, plurality of electrodes  442  can be configured with a higher granularity than electrode  422  and/or plurality of electrodes  432 . Changes in granularity can be obtained in one or more ways including, but not limited to, different materials and/or material properties, different configurations of coupled electrodes, and different size electrodes. In some examples, electrode  422  and/or plurality of electrodes  432  can be configured with a higher granularity than plurality of electrodes  442 . In some examples, the number of electrodes  432  disposed on layer  430  can be greater than the number of electrodes  442  disposed on layer  440 . In some examples, the number of electrodes  432  disposed on layer  430  can be less than or equal to the number of electrodes  442  disposed on layer  440  (not shown). In some examples, two or more of electrode  422 , plurality of electrodes  432 , and plurality of electrodes  442  can include any conductive material including, but not limited to, silver, copper, gold, aluminum, steel, brass, bronze, and graphite. In some examples, two or more of electrode  422 , plurality of electrodes  432 , and plurality of electrode  442  can include the same materials. 
     In some examples, the exemplary mat can include an additional layer (not shown) configured to provide support or electrical insulation from one or more materials or layers (e.g., the mattress). In some examples, the additional layer can include one or more electrodes (not shown). 
     In some examples, the monitoring system can include one or more shielding electrodes to limit capacitive coupling of the system with external sources. In some examples, the one or more shielding electrodes can be a separate layer in the system. In some examples, one or more of the plurality of electrodes  432 , plurality of electrodes  442 , or both can be configured as shielding electrodes. In some examples, one or more of the plurality of electrodes  432  (and/or plurality of electrodes  442 ) can be configured to measure electrical signals and one or more adjacent electrodes  432  (and/or plurality of electrodes  442 ) can be configured for shielding. 
     The exemplary mat can be configured with any number of layers and/or arrangement of layers relative to the other layers. For example, as illustrated in  FIG. 4C , layer  430  can be located on one side of layer  420 , and layer  440  can be located on the other side of layer  420 . Plurality of electrodes  432  disposed on layer  430  can be located on the opposite side of layer  430  than user  498 . Electrode  422  can be located between layer  420  and layer  440 , and plurality of electrodes  442  can be located on the opposite side of layer  440  than electrode  422 . 
     In additional to measuring changes in capacitance to form one or more images of the user&#39;s position and form at least a portion of a BCG measurement, the plurality of electrodes  442  can be configured for sensing electrical signals. The measured electrical signals can be used to form at a least a portion of an electrocardiogram (ECG) measurement. The ECG measurement can include changes in electrical impulses due to heart contractions and blood flow. In some examples, the monitoring system can be configured such that measurements from the electrodes located directly underneath the user&#39;s body are included in the ECG measurement, since these electrodes can have higher coupling to the user&#39;s electrical impulses. In some examples, the electrodes located directly under the user&#39;s body can be effected by less movement than electrodes located in the immediate periphery (i.e., adjacent to the electrodes located directly under the body of the user) of the user&#39;s body. The ECG measurement can be used at least partially to measure the heart rate, heart rate variability, respiratory rate, and/or respiratory rate variability. 
       FIGS. 4D-1 and 4D-2  illustrate an exemplary process flow for capacitive and electrical measurements according to examples of the disclosure. In some examples, the monitoring system can operate in multiple modes: one mode (i.e., first mode) for measuring capacitance values and another mode (i.e., second mode) for measuring electrical signals. During the first mode, drive circuitry can stimulate one or more drive electrodes creating a mutual capacitance with one or more sense electrodes (step  452  of process  450 ). Sense circuitry can be coupled to one or more sense electrodes. Sense circuitry can measure any changes in capacitance caused by the user&#39;s force that can change the distance between the drive and sense electrodes (step  454  of process  450 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s body position and/or location on the mat (step  456  of process  450 ). The controller or processor can determine which drive and/or sense electrodes are not affected by the user&#39;s force or body weight (step  458  of process  450 ) and can disable or disconnect the drive and/or sense electrodes to conserve power, for example (step  460  of process  450 ). In some examples, the controller can select the drive and/or sense electrodes that are located in the immediate periphery of the user&#39;s body or the periphery of the mat for the capacitive measurements. The measured capacitance values can be used to form at least a portion of a BCG measurement (step  462  of process  450 ). The first mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  464  of process  450 ). In some examples, the first mode can be repeated after the second mode has been completed (step  466  of process  450 ). 
     During the second mode, one or more electrodes can be configured to measure the electrical impulses from the user&#39;s heart (step  468  of process  450 ). In some examples, the difference in electrical potential between multiple electrodes can be measured. The controller or processor can determine which electrodes are not affected by the electrical signals of the user&#39;s heart (step  470  of process  450 ) and can disable or disconnect the electrodes to conserve power, for example (step  472  of process  450 ). In some examples, the controller can select the electrodes located underneath the user&#39;s body for electrical measurements. The measured electrical signals can be used to form at least a portion of an ECG measurement (step  474  of process  450 ). In some examples, the electrical signals can be used to determine the user&#39;s body position, user&#39;s body location, the location of the user&#39;s heart, or a combination thereof (step  476  of process  450 ). In some examples, step  456  can be used to form a rough estimate or coarse image of the user&#39;s body position and/or location, and step  474  can be used to form a more detailed or finer imager of the user&#39;s body position and/or location. The second mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  478  of process  450 ). In some examples, the second mode can be repeated after the first mode has been completed (step  480  of process  450 ). 
     Although  FIGS. 4D-1 and 4D-2  illustrate the controller beginning with the first mode measurement, examples of the disclosure can include beginning with the second mode measurement or beginning with both the first and second mode measurements. Although  FIG. 4D  illustrates the controller performing the first and second mode measurements sequentially, examples of the disclosure can include performing the first and second mode measurements concurrently. Moreover, examples of the disclosure can include using information measured during one mode (e.g., first mode) for and/or in conjunction with another mode (e.g., second mode). 
       FIG. 4E  illustrates a cross-sectional view of an exemplary mat according to examples of the disclosure. In some examples, the plurality of electrodes  442  can be configured to measure the electrical signals from the heart of user  498 . Configuring the monitoring system such that the plurality of electrodes  442  are located at or near the surface of user  498  can lead to more accurate measurements of the electrical signals. In some examples, layer  440  can be located on one side of layer  420 , and layer  430  can be located on the opposite side of layer  420 . Plurality of electrodes  442  can be located on one side of layer  440 , and user  498  can be located either on the same side of layer  440  (not shown) or on the opposite side of layer  440 . Electrode  422  can be located between layer  420  and layer  430 . Plurality of electrodes  432  can be located on the opposite side of layer  430  than the side that electrode  422  is located on. 
       FIG. 4F  illustrates a cross-sectional view of an exemplary mat according to examples of the disclosure. In some examples, the number of layers including electrodes can be reduced and/or the functionality of one or more electrodes can be dynamically switched by including one or more switching matrices, such as switching matrix  491  and switching matrix  492 . Switching matrix  491  can be configured to couple or decouple one or more of the plurality of electrodes  432 , and switching matrix  492  can be configured to couple or decouple one or more of the plurality of electrodes  442 . 
     In some examples, switching matrix  491  and switching matrix  492  can be configured for capacitive measurements. Switches included in switching matrix  491  can be configured such that the plurality of electrodes  432  can be electrically isolated from one another and coupled to drive circuitry. Switches included in switching matrix  492  can be configured such that the electrodes in the plurality of electrodes  442  can be electrically coupled together and coupled to sense circuitry. 
     In some examples, switching matrix  491  and switching matrix  492  can be configured for ECG measurements and (optional) shielding. Switches included in switching matrix  491  can be configured such that the plurality of electrodes  432  can be electrically isolated from one another. The plurality of electrodes  432  can be configured to measure the electrical signals of user  498 . The switches included in switching matrix  491  can be configured such that the electrodes in the plurality of electrodes  442  are electrically coupled together and function as a shielding layer. 
     In some examples, switching matrix  491  and switching matrix  492  can be configured to have different granularities in the mat based on the user&#39;s body position and/or location. For example, the switching matrix can decouple electrodes for more granularity in locations where the user&#39;s body parts may require a more sensitive measurement (e.g., the area corresponding to the user&#39;s heart), or couple electrodes for less granularity in locations where less sensitive measurements are acceptable (e.g., areas where the user&#39;s body may not be present). 
     In some examples, the monitoring system can include one or more switching matrices, where the switching matrices can be configured to partition (e.g., separate measurement information) the mat into multiple sections.  FIG. 5A  illustrates a top view of an exemplary monitoring system including multiple sections according to examples of the disclosure. System  599  can include a plurality of electrodes, such as plurality of electrodes  532 , plurality of electrodes  534 , plurality of electrodes  536 , and plurality of electrodes  538 . Multiple users, such as user  596  and user  598 , can be positioned on system  599 . System  599  can determine that there are multiple users and can partition system  599  into multiple sections, such as section  501  and section  503 . In some examples, measurements in one section, such as section  501 , can be taken independently from measurements in another section, such as section  503 . In some examples, the plurality of sections can be specified at the time of manufacture. In some examples, the size, number, and/or shape of the plurality of sections can be dynamically configured using one or more switching matrices. For example, system  599  can associate user  598  with section  501  and user  596  with section  503 . For capacitance measurements, system  599  can couple section  501  to a first drive and sense circuitry using a switching matrix and can couple section  503  to a second drive and sense circuitry using the same or another switching matrix. The system can be configured to capture a plurality of images, where each image can include a matrix of measurement values that represent the position of the user within a given section. Additionally, a plurality of measurements of electrical signals can be taken, such as a measurement of electrical signals in section  501  that can be separate and independent from the measurement of electrical signals in section  503 . System  599  can associate each measurement with a given user or a given section and can perform analysis specific to that user or section. 
       FIGS. 5B-1 to 5B-3  illustrate an exemplary process flow for dynamically partitioning the mat into multiple sections according to examples of the disclosure. Drive circuitry can stimulate one or more drive electrodes creating a mutual capacitance with one or more sense electrodes (step  552  of process  550 ). In some examples, all of the drive electrodes can be stimulated to allow the monitoring system to partition the entire mat. Sense circuitry can be coupled to one or more sense electrodes. Sense circuitry can measure any changes in capacitance caused by the user&#39;s force causing changes in the distances between the drive and sense electrodes (step  554  of process  550 ). Controller can form an image of the user&#39;s body position and/or location on the mat (step  555  of process  550 ). Based on the image, the system can determine that there are multiple users located on the mat, and the controller can partition the mat into multiple sections (step  556  of process  550 ). In some examples, one or more switching matrices can couple (or decouple) two or more electrodes to decrease (or increase) the granularity (step  558  of process  550 ). For example, increased granularity for discerning the boundaries of the body position and/or locations of the multiple users may not be needed, for example, when the users are spatially separated far apart (e.g., more than one electrode not subjected to either user&#39;s body can be located between users). 
     In some examples, the measurements of each section can be taken independently. Each section can operate in multiple modes: one mode (i.e., first mode) for measuring capacitance values and another mode (i.e., second mode) for measuring electrical signals. In some examples, the mode of operation of a given section can be independent from the other section(s). 
     During a first mode for a first section (e.g., section  501  illustrated in  FIG. 5A ), drive circuitry can stimulate one or more drive electrodes (e.g., electrodes  536  and electrodes  538  illustrated in  FIG. 5A ) in the first section to create a mutual capacitance with one or more sense electrodes in the first section (step  560 A of process  550 ). Sense circuitry can be coupled to one or more sense electrodes in the first section. Sense circuitry can measure any changes in capacitance caused by the force of the user (e.g., user  598 ) that can change the distance between the drive and sense electrodes associated with the first section (step  562 A of process  550 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s body position and/or location in the first section (step  564 A of process  550 ). The controller or processor can determine which drive and sense electrodes are not affected by the user&#39;s force in the first section (step  566 A of process  550 ) and can disable or disconnect the drive and/or sense electrodes (e.g., electrodes  536  illustrated in  FIG. 5A ) in the first section to conserve power, for example (step  568 A of process  550 ). The measured capacitance values can be used to form at a least a portion of a first BCG measurement associated with the first section (step  570 A of process  550 ). Operation of the first section in the first mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location in the first section changes (step  572 A of process  550 ). In some examples, operation of the first section in the first mode can be repeated after operation of the first section in the second mode has been completed (step  574 A of process  550 ). In some examples, operation of the first section in the first mode can depend on operation of the second section. 
     During operation of the first section (e.g., section  501  illustrated in  FIG. 5A ) in the second mode, one or more electrodes (e.g., electrode  538  illustrated in  FIG. 5A ) can be configured to measure electrical impulses from the heart of the user (e.g., user  598 ) located in the first section (step  576 A of process  550 ). In some examples, the difference in electrical potentials between multiple electrodes can be measured. The controller or processor can determine which electrodes in the first section are not affected by the electrical signals of the user&#39;s heart (step  578 A of process  550 ) and can disable or disconnect the electrodes to conserve power, for example (step  580 A of process  550 ). The measured electrical signals can be used to form at least a portion of a first ECG measurement (step  582 A of process  550 ). In some examples, the electrical signals can be used to determine the user&#39;s body position, the user&#39;s body location, the location of the user&#39;s heart, or a combination thereof (step  584 A of process  550 ). In some examples, step  564 A (and/or step  552  and step  554 ) can be used to form a rough estimate or coarse image of the user&#39;s body position and/or location, and step  584 A can be used to form a more detailed or finer image of the user&#39;s body position and/or location. Operation of the first section in the second mode can be repeated after a predetermined time interval and/or when the body position and/or location of the user in the first section change (step  586 A of process  550 ). In some examples, operation of the first section in the second mode can be repeated after operation of the first section in the first mode has been completed (step  588 A of process  550 ). In some examples, operation of the first section in the second mode can depend on operation of the second section. 
     At the same time or at a time different from operating the first section, the second section (e.g., section  503  illustrated in  FIG. 5A ) can operate in the first mode. Drive circuitry can stimulate one or more drive electrodes (e.g., electrodes  532  and electrode  534  illustrated in  FIG. 5A ) in the second section to create a mutual capacitance with one or more sense electrodes in the second section (step  560 B of process  550 ). Sense circuitry can be coupled to one or more sense electrodes in the second section. Sense circuitry can measure any changes in capacitance caused by the force of the user (e.g., user  596 ) that can change the distance between the drive and sense electrodes associated with the second section (step  562 B of process  550 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s position in the second section (step  564 B of process  550 ). The controller or processor can determine which drive and sense electrodes are not affected by the user&#39;s force in the second section creating separations between drive and sense electrodes (step  566 B of process  550 ) and can disable or disconnect the drive and/or sense electrodes (e.g., electrodes  532  illustrated in  FIG. 5A ) in the second section to conserve power, for example (step  568 B of process  550 ). The measured capacitance values can be used to form at a least a portion of a second BCG measurement associated with the second section (step  570 B of process  550 ). Operation of the second section in the first mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location in the second section changes (step  572 B of process  550 ). In some examples, operation of the second section in the first mode can be repeated after operation of the second section in the second mode has been completed (step  574 B of process  550 ). In some examples, operation of the second section in the first mode can depend on operation of the second section. 
     During operation of the second section (e.g., section  503  illustrated in  FIG. 5A ) in the second mode, one or more electrodes (e.g., electrode  534  illustrated in  FIG. 5A ) can be configured to measure electrical impulses from the heart of the user (e.g., user  596 ) located in the second section (step  576 B of process  550 ). In some examples, the differences in electrical potential between multiple electrodes can be measured. The controller or processor can determine which electrodes in the second section are not affected by the electrical signals of the user&#39;s heart (step  578 B of process  550 ) and can disable or disconnect the electrodes to conserve power, for example (step  580 B of process  550 ). The measured electrical signals can be used to form at a least a portion of a second ECG measurement (step  582 B of process  550 ). In some examples, the electrical signals can be used to determine the user&#39;s body position, the user&#39;s body location, the location of the user&#39;s heart, or a combination thereof (step  584 B of process  550 ). In some examples, step  564 B (and/or step  552  and step  554 ) can be used to form a rough estimate or coarse image of the user&#39;s body position and/or location, and step  584 B can be used to form a more detailed or finer image of the user&#39;s body position and/or location. Operation of the second section in the second mode can be repeated after a predetermined time interval and/or when the body position and/or location of the user in the second section changes (step  586 B of process  550 ). In some examples, operation of the second section in the second mode can be repeated after operation of the second section in the first mode has been completed (step  588 B of process  550 ). In some examples, operation of the second section in the second mode can depend on operation of the first section. 
     If any one of the number of users, the size of one or more sections, and the locations of one or more sections changes (step  590  of process  550 ), the system can return to selecting the number of sections and partitioning the system into the selected number of sections. Although  FIG. 5B  illustrates step  590  as after step  588 A and step  588 B, examples of the disclosure can include selecting the number of sections and partitioning the system into the selected number of sections at any step in the process. 
     At any time, the controller can utilize other (e.g., predetermined) information to discern between users and to form the sections. For example, if two users are contacting each other or in close proximity to each other, the controller may not be able to discern whether one or more electrodes are measuring one user, the other user, or both. The controller can associate the measurement information (e.g., stored in a database or in memory) to characteristics of the human anatomy. For example, if the overall measurement image does not match the outline of one user, the controller may determine that more than one user can be utilizing the system. The controller may attempt to match the measurement image to differing combinations of user positions and/or may use other measured information (e.g., location of a user&#39;s heart based on the intensity of the electrical signals) to discern between the multiple users. 
     Although  FIG. 5A  illustrates the monitoring system being partitioned into two sections, examples of the disclosure can include any number of sections including, but not limited to, one or greater than two sections. In some examples, the monitoring system can be capable of further partitioning selected sections.  FIG. 5C  illustrates a top view of an exemplary monitoring system including multiple sections according to examples of the disclosure. Multiple users, such as user  596 , user  597 , and user  598 , can be located on system  599 . System  599  can be capable of detecting the body position and/or locations of the multiple users and can be capable of partitioning the system into a plurality of sections, such as section  503 , section  505 , and section  507 . In some examples, system  599  can select less than all of the sections to further partition into multiple sections, where the partitioning can be dynamic. For example, user  596  and user  598  can be located on system  599 . System  599  can detect the presence of multiple users and can dynamically partition into two sections (e.g., section comprising the left side of system  599  and section  503 ). User  598  located in the left section can change body position and/or location. For example, user  598  can move closer to the upper edge of system  599  to make room for user  597 , as shown in  FIG. 5C . System  599  can detect the change in body position and/or location of user  598  and can dynamically partition left section into multiple sections, such as section  505  and section  507 . In some examples, dynamically partitioning a section can include measuring the capacitance values and/or electrical signals using any or all of the techniques previously discussed. In some examples, while dynamically partitioning the left section into multiple sections, the size, shape, and/or location of section  503  can be maintained. In some examples, maintaining section  503  can include omitting capacitance and/or electrical measurements to determine the size, shape, and/or location of section  503  and/or the body position and/or location of user  599 . In some examples, one or more sections can be inactivated if, for example, analysis of the user (e.g., user  597 ) is not desired. 
       FIGS. 6A-6B  illustrate top and perspective views of layers included in an exemplary mat according to examples of the disclosure. The exemplary mat can include layer  620  and layer  630 . The design and/or operation of layer  630 , plurality of electrodes  632 , and electrode  622  can include the design and/or operation of layer  230 , plurality of electrodes  232 , and electrode  222 , respectively, as discussed above. In some examples, the exemplary mat can include an additional layer (not shown) configured to provide support or electrical insulation from one or more materials or layers (e.g., the mattress). In some examples, the additional layer can include one or more electrodes (not shown). 
     Layer  630  can further include one or more piezoelectric sensors  634 . Piezoelectric sensors  634  can include a sensor capable of generating one or more electrical signals in response to one or more changes in material properties (e.g., pressure or force). Examples of the disclosure can include piezoresistive sensors. The user&#39;s heartbeat can create mechanical impulses, which can change the properties of piezoelectric sensors  634 . The piezoelectric measurement can form at least a portion of a BCG measurement. In some examples, piezoelectric sensors  634  can be located in areas of mat with greater strain than other areas. System  699  can include any number, size, and/or shape of piezoelectric sensors  634 . In some examples, piezoelectric sensors  634  can include sections of rigid material physically connected together by flexible material. The rigidity of a piezoelectric sensor and the material between piezoelectric sensors can be adjusted. In some examples, piezoelectric sensors  634  can be interleaved with one or more rows of plurality of electrodes  632 . In some examples, some of piezoelectric sensors  634  can be activated, and some of the piezoelectric sensors  634  can be deactivated at any given time based on the location of the user. For example, activated piezoelectric sensors can be located directly under (or in the immediate periphery of) the user, whereas deactivated piezoelectric sensors can be located elsewhere. 
       FIGS. 6C-6D  illustrate cross-sectional views of an exemplary mat according to examples of the disclosure. The exemplary mat can be configured with any number of layers and/or arrangement of layers relative to the other layers. For example, as illustrated in  FIG. 6C , layer  620  can be located on one side of layer  630 , and user  698  can be located on the other side of layer  630 . Plurality of electrodes  632  and plurality of piezoelectric sensors  634  can be located between layer  620  and layer  630 . Electrode  622  can be located on the opposite side of layer  620  than plurality of electrodes  632 . In some examples, as illustrated in  FIG. 6D , layer  630  can be located on one side of layer  620 , and user  698  can be located on the other side of layer  620 . Electrode  622  can be located between layer  620  and layer  630 . Plurality of electrodes  632  and plurality of piezoelectric sensors  634  can be located on the opposite side of layer  630  than electrode  622 . 
     Electrode  622 , plurality of electrodes  632 , and plurality of piezoelectric sensors  634  can be configured with one or more functionalities. The design and/or operation of layer  630 , plurality of electrodes  632 , and electrode  622  can include the design and/or operation of layer  230 , plurality of electrodes  232 , and electrode  222 , respectively, as discussed above. In some examples, plurality of electrodes  632  can be configured as multifunctional sensors capable of measuring capacitance during one mode and measuring electrical signals during another mode. In some examples, some of the plurality of electrodes  632  can be configured to measure capacitance and others of the plurality of electrodes  632  can be configured to measure electrical signals. In some examples, the monitoring system can include one or more switching matrices (not shown) configured to couple or decouple together sections of electrode  622  (not shown), two or more of the plurality of electrodes  632 , and/or two or more piezoelectric sensors  634 . 
     In some examples, the monitoring system can operate in multiple modes: a first mode for measuring capacitance, a second mode for measuring electrical signals, and a third mode for measuring changes in pressure.  FIGS. 6E-1 and 6E-2  illustrate an exemplary process flow for capacitive, electrical, and piezoelectric measurements according to examples of the disclosure. During the first mode, drive circuitry can stimulate one or more drive electrodes creating a mutual capacitance with one or more sense electrodes (step  652  of process  650 ). Sense circuitry can be coupled to one or more sense electrodes. Sense circuitry can measure any changes in capacitance caused by the user&#39;s force that can change the distance between the drive and sense electrodes (step  654  of process  650 ). A controller or processor coupled to sense circuitry can form an image of the user&#39;s body position and/or location on the mat (step  656  of process  650 ). The controller or processor can determine which drive and/or sense electrodes are not affected by the user&#39;s force or body weight (step  658  of process  650 ) and can disable or disconnect the drive and/or sense electrodes to conserve power, for example (step  660  of process  650 ). The measured capacitance values can be used to form at least a portion of a BCG measurement (step  662  of process  650 ). The first mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  664  of process  650 ). In some examples, the first mode can be repeated after the second mode has been completed (step  666  of process  650 ). 
     During the second mode, one or more piezoelectric sensors can be configured to measure the changes in pressure on the sensors from the user&#39;s body movement (step  668  of process  650 ). The controller or processor can determine which piezoelectric sensors are not affected by change in pressure due to the user&#39;s body movement (step  670  of process  650 ) and can disable or disconnect the piezoelectric sensors to conserve power, for example (step  672  of process  650 ). In some examples, the controller or processor can compare the strain of all or some of the piezoelectric sensors; can enable the piezoelectric sensors located in areas of the mat with greater strain than in other areas; and can disable the piezoelectric sensors located in the other areas. The measured piezoelectric signals can be used to form at a least portion of the BCG measurement (step  674  of process  650 ). 
     In some examples, the electrodes and piezoelectric sensors can be configured to measure the same type of information, but at different levels of granularity. For example, BCG information can be used to determine the user&#39;s body movement. Mutual capacitance measurements (i.e., step  654 ) can be used to form a rough estimate or coarse determination of the user&#39;s body movement, and the piezoelectric measurements (i.e., step  658 ) can be used for a more accurate determination of the user&#39;s body movement. Although a user&#39;s breathing can cause a motion artifact, the breathing motion can different from gross motion due to the user moving or stirring. Being able to discriminate gross motion from breathing can lead to a more accurate analysis. In some examples, the mutual capacitance measurements can be used to measure displacement of the user&#39;s body, while the piezoelectric measurements can be used to measure the velocity of the user&#39;s body. 
     The third mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  676  of process  650 ). In some examples, the second mode can be repeated after the first mode has been completed (step  678  of process  650 ). Although  FIG. 6E  illustrates the controller beginning with the first mode measurement, examples of the disclosure can include beginning with the second mode measurement or beginning with both the first and second mode measurements. Although  FIG. 6E  illustrates the controller performing the first and second mode measurements sequentially, examples of the disclosure can include performing the first and second mode measurements concurrently. 
     In some examples, monitoring system can include a plurality of piezoelectric sensors.  FIGS. 7A-7B  illustrate top views of exemplary layers included in a mat according to examples of the disclosure. Piezoelectric sensors can include any size, size, and/or resolution. For example, piezoelectric sensors  735  can be rectangular and/or have a length greater than electrodes  732 , as illustrated in  FIG. 7A . Layer  730  can be configured such that piezoelectric sensor  735  on one side can be configured for one user, and piezoelectric sensor  735  on the other side can be configured for another user. In some examples, the piezoelectric sensors  735  can be electrically isolated from each other allowing independent measurements to be taken for different users. In some examples, some of piezoelectric sensors  735  can be enabled, and some of piezoelectric sensors  735  can be disabled. When the user moves in a direction perpendicular to the long axis of the piezoelectric sensors  735 , the enabled and disabled piezoelectric sensors  735  can change. In some examples, piezoelectric sensors  735  enabled on one side of the mat can be longitudinally displaced from the piezoelectric sensors  735  enabled on the other side. Layer  730  can further include a plurality of electrodes  732 . 
     In some examples, piezoelectric sensors  736  can have the same size as electrodes  732 , as illustrated in  FIG. 7B . Layer  730  can include a plurality of electrodes  732  and a plurality of piezoelectric sensors  736 . Given the smaller size and greater number of piezoelectric sensors (e.g., compared to the mat illustrated in  FIG. 7A ), the resolution of the piezoelectric measurement can be greater. In some examples, each piezoelectric sensor  736  can include sections of rigid material that can be physically connected to by flexible material. The rigidity of a piezoelectric sensor and the material between piezoelectric sensors can be adjusted. Plurality of piezoelectric sensors  736  can be located in any arrangement including, but not limited to, one or more rows of piezoelectric sensors  736  running across the mat or a matrix of rows and columns of piezoelectric sensors. In some examples, each of the piezoelectric sensors  736  can be electrically isolated and independently controlled from the other piezoelectric sensors  736 . The monitoring system can be configured to form an image representative of the changes in pressure across the mat. 
     In some examples, one or more electrodes can be disposed on one or more piezoelectric sensors.  FIGS. 7C-7D  illustrate top and cross-sectional views of an exemplary mat including electrodes disposed on piezoelectric sensors according to examples of the disclosure. The exemplary mat can include layer  720  and layer  730 . Layer  720  can include electrode  722 . 
     Layer  730  can include a plurality of sensors  737 . Plurality of sensors  737  can include one or more electrodes  732  and one or more piezoelectric sensors  736 . Sensors  737  can be capable of measuring capacitance values between electrode  722  and electrode  733 , measuring changes in pressure from piezoelectric sensor  736 , and/or measuring electrical signals from electrode  722  and/or electrode  732 . The mat can be configured with every other row including sensors  737  (i.e., electrodes  732  disposed on piezoelectric sensors  736 ) and the other rows including only electrodes  732 , as illustrated in  FIG. 7C . 
       FIGS. 7E-7G  illustrate cross-sectional views of exemplary mats according to examples of the disclosure. In some examples, as illustrated in  FIG. 7E , system  799  can include sub-mat  702  and sub-mat  704  with user  798  located between sub-mat  702  and sub-mat  704 . Sub-mat  702  can include layer  720  and electrode  722 . In some examples, electrode  722  can be deposited on a substantial (e.g., 75%) area of layer  720 . Electrode  722  can be continuous (i.e., a discrete piece of material). Sub-mat  704  can include layer  730 , a plurality of electrodes  732 , and a plurality of piezoelectric sensors  734 . Electrode  722 , plurality of electrodes  732 , or both can include any conductive material including, but not limited to, silver, copper, gold, aluminum, steel, brass, bronze, and graphite. In some examples, electrode  722  and plurality of electrodes  732  can include the same materials. 
     Electrode  722  and plurality of electrodes  732  can be configured with one or more functionalities. The design and/or operation of layer  730 , plurality of electrodes  732 , and electrode  722  can include the design and/or operation of layer  330 , plurality of electrodes  332 , and electrode  322 , respectively, as discussed above. Additionally, the design and/or operation of piezoelectric sensors  734  and piezoelectric sensors  736  can include the design and/or operation of piezoelectric sensors  634 , as discussed above. 
     In some examples, electrode  722  can include one or more sections of conductive material electrically coupled together for capacitance and/or BCG measurements. In some examples, electrode  722  can include a plurality of electrodes and can be further configured as sensing electrodes capable of sensing electrical signals for ECG measurements. In some examples, plurality of piezoelectric sensors  734  can be configured to measure changes in pressure/force caused by the mechanical impulses from the user&#39;s blood acceleration. In some examples, plurality of electrodes  732  can be configured as multifunctional sensors capable of measuring capacitance during one mode and measuring electrical signals during another mode. In some examples, some of the plurality of electrodes  732  can be configured to measure capacitance and others of the plurality of electrodes  732  can be configured to measure electrical signals. In some examples, system  799  can include one or more switching matrices (not shown) configured to couple or decouple together sections of electrode  722  (not shown), two or more of the plurality of electrodes  732 , and/or two or more piezoelectric sensors  734 . 
     In some examples, sub-mat  702  can include a switching matrix (not shown). The switching matrix can be configured to electrically couple one or more electrodes included in the plurality of electrodes  732  together and/or one or more piezoelectric sensors included in the plurality of piezoelectric sensors  734  together. The system can be capable of dynamically switching one or more electrodes utilized for the capacitance measurements. For example, in a first mode, user  798  can be located between sub-mat  702  and sub-mat  704 . Electrode  722  can be configured as a sense electrode, and the plurality of electrodes  732  can be configured as drive electrodes. Changes in capacitance values can be due to the user&#39;s body parts increasing the separations between the sense and drive electrodes. In a second mode, sub-mat  704  can be removed from system  799  or located a certain distance away. The separation between sub-mat  704  from sub-mat  702  can prevent electrode  722  from capacitively coupling to plurality of electrodes  732 , or the measured capacitance values can be below a predetermined threshold. 
     The switching matrix can electrically couple together the plurality of electrodes  732  and/or electrically couple together the plurality of piezoelectric sensors  734 . The electrically coupled electrodes  732  can be configured as a drive electrode, and electrode  722  can be configured as a sense electrode. Changes in capacitance values can be due to the user&#39;s body weight applying a force that can change the distance between the sense and drive electrodes. When sub-mat  704  is returned back to system  799  and located a close enough distance such that electrode  722  can capacitively couple to the plurality of electrodes  732 , system  799  can remain in the second mode or switch to the first mode. 
     Although  FIG. 7E  illustrates layer  730  located closer to user  798  than plurality of electrodes  732  and plurality of piezoelectric sensors  734  and layer  720  located closer to user  798  than electrode  722 , examples of the disclosure can include plurality of electrodes  732  and plurality of piezoelectric sensors  734  located closer to user  798  than layer  730 , electrode  722  located closer to user  398  than layer  720 , or both. In some examples, sub-mat  702  and/or sub-mat  704  can include a layer (not shown) configured to provide support or electrical insulation from one or more materials or layers (e.g., the mattress), for example. In some examples, as illustrated in  FIG. 7F , plurality of electrodes  732  and the plurality of piezoelectric sensors  734  can be included in sub-mat  702  along with layer  730 . Additionally or alternatively, electrode  722  and layer  720  can be included in sub-mat  704 . 
     In some examples, capacitance values can be measured between sub-mats, between a layer in the sub-mat, or both.  FIG. 7G  illustrates a cross-sectional view of an exemplary mat according to examples of the disclosure. In some examples, electrode  722  and electrode  742  can be configured as sense electrodes, and plurality of electrodes  732  can be configured as drive electrodes. System  799  can be configured such that stimulating some of the plurality of electrodes  732  can create a mutual capacitance with electrode  722 , and stimulating others of the plurality of electrodes  732  can create a mutual capacitance with electrode  742 . In this manner, the individual or combination of the measured capacitance values can be used to determine more information about the user&#39;s sleep. For example, the user  798  can be positioned with its back contacting sub-mat  702  and fingers contacting only sub-mat  704 . Movement of the user&#39;s fingers may not be detected by electrodes located in sub-mat  702  due to the low change in pressure that can be associated with finger movements and the distance from the user&#39;s fingers and the electrodes located in sub-mat  702 . However, fingers can be contacting or in close proximity to sub-mat  704 , so one or more electrodes, such as electrode  742 , included sub-mat  704  can be capable of detecting the user&#39;s finger movements. In some examples, electrodes included in sub-mat  702  can be configured to measure larger changes in body movements, and electrodes included in sub-mat  704  can be configured to measure smaller changes in body movements. 
     In some examples, the mat can include one or more temperature sensors.  FIG. 8A  illustrates a top view of an exemplary layer of a mat including a plurality of electrodes, a plurality of piezoelectric sensors, and a plurality of temperature sensors according to examples of the disclosure. Layer  830  can include a plurality of electrodes  832 , a plurality of piezoelectric sensors  834 , and a plurality of temperature sensors  838 . Plurality of electrodes  832  can be configured for measuring capacitance values and/or electrical signals. The design and/or operation of plurality of electrodes  832  and plurality of piezoelectric sensors  834  can include the design and/or operation of plurality of electrodes  232  and plurality of piezoelectric sensors  634 , respectively, as discussed above. 
     Plurality of temperature sensors  838  can be any type of sensor capable of measuring temperature including, but not limited to, a resistance thermometer, a thermistor, and a thermocouple. In some examples, one or more of the plurality of temperature sensors  838  can be located on the same layer as one or more of electrodes  832  and piezoelectric sensors  834 . In some examples, the system can include one or more temperature sensors, such as temperature sensor  836 , configured to measure the temperature of the room. In some examples, temperature sensors  836  can be in addition or instead of temperature sensors (e.g., temperature sensors  139  illustrated in  FIG. 1 ) located in the control system (e.g., control system  140 ). Although  FIG. 8A  illustrates three different types of sensors (i.e., electrodes, piezoelectric sensors, and temperature sensors), examples of the disclosure can include some, but not all, of the different types of sensors. 
       FIGS. 8B-8C  illustrate cross-sectional and top views of the monitoring system including temperature sensors according to examples of the disclosure. The plurality of temperature sensors (e.g., plurality of temperature sensors  838  illustrated in  FIG. 8A ) can include multiple sets of temperatures sensors, such as plurality of temperature sensors  835 , plurality of temperature sensors  837 , and plurality of temperature sensors  839 . In some examples, each set can include the same type of temperature sensor. In some examples, temperature measurements from each set can be utilized in a different manner (discussed below). In some examples, plurality of temperature sensors  835  can be located in areas outside of where user  898  can be located. 
     Plurality of temperature sensors  837  can be configured to measure the temperature of the local ambient (i.e., the space between the sub-mats  802 ). In some examples, plurality of temperature sensors  837  can be located in close proximity to, but not directly below user  898 . In some examples, plurality of temperature sensors  837  can be located at or in close proximity to where sub-mat  804  contacts sub-mat  802  (as illustrated in  FIG. 8B ). Plurality of temperature sensors  839  can be configured to measure the temperature of user  898 . By measuring the temperatures of both user  898  and the local ambient, the monitoring system can associate the temperatures in the sleep analysis of the user (discussed below). 
     In some examples, system  899  can be capable of determining the location of user  898  to disable or disconnect the temperature sensors (e.g., plurality of temperature sensors  835 ) not affected by the user&#39;s body temperature or not within close proximity to the user&#39;s body. In some examples, plurality of temperature sensors  839  can be located below user  898 . In some examples, system  899  can be configured to dynamically change which temperature sensors are not associated with the user, which temperature sensors are associated with the temperature of user  898 , and which temperature sensors are associated with the local ambient. Any of the temperature sensors (e.g., temperature sensors  935 , temperature sensors  937 , and temperature  939 ) can be coupled together using one or more switches. 
       FIG. 8D  illustrates an exemplary process flow for temperature measurements according to examples of the disclosure. In some examples, the monitoring system can measure temperatures across the mat and can create a temperature image (step  852  of process  850 ). The monitoring system can determine the location of the user&#39;s body (step  854  of process  850 ). In some examples, the monitoring system can utilize the temperature image to associate boundaries of the user&#39;s body to differences in temperature. In some examples, determining the location of the user&#39;s body can include any of the capacitance measurements, electrical measurements, piezoelectric measurements, or any combination thereof. For example, plurality of temperature sensors  835  and plurality of temperature sensors  837  can have different temperatures than plurality of temperature sensors  839  due to the differences in temperature between locations where the user is not located (measured by plurality of temperature sensors  835  and plurality of temperature sensors  837 ) and locations where the user is located (measured by the plurality of temperature sensors  839 ). Based on the different temperatures, the monitoring system can determine where the user&#39;s body is located. In some examples, plurality of temperature sensors  837  can have different temperatures than plurality of temperature sensors  835  due to the gap between sub-mat  802  and sub-mat  804  (as illustrated in  FIG. 8B ), and monitoring system can further uses these differences to determine the user&#39;s body location and/or to associate the temperature sensors in the sleep analysis of the user. 
     In some examples, the monitoring system can assign each temperature sensor to a certain set (step  856  of process  850 ), where each set can correspond to a type of area (e.g., locations not in close proximity to the user, locations in close proximity to the user, locations underneath the user) of the mat. A controller coupled to the temperature sensors can determine which temperature sensors correspond to locations not in close proximity to the user (step  858  of process  850 ) and can disable or disconnect those temperature sensors to conserve power, for example (step  860  of process  850 ). The measured temperatures can be used at least partially in determining the temperatures of the user&#39;s body and local ambient (step  862  of process  850 ). Examples of the disclosure can include measuring capacitance values, electrical signals, and/or piezoelectric signals at the same time or at different times than measuring the temperatures. 
     In some examples, the mat can include one or more accelerometers.  FIG. 9  illustrates a top view of an exemplary layer of a mat including a plurality of electrodes, a plurality of piezoelectric sensors, a plurality of temperature sensors, and a plurality of accelerometers according to examples of the disclosure. Layer  930  can include a plurality of electrodes  932 , a plurality of piezoelectric sensors  934 , a plurality of temperature sensors  938 , and a plurality of accelerometers  942 . The design and/or operation of plurality of electrodes  932  and plurality of piezoelectric sensors  934  can include the design and/or operation of plurality of electrodes  232  and plurality of piezoelectric sensors  634 . 
     Plurality of accelerometers  942  can any type of device configured for measuring acceleration or vibrations. In some examples, the plurality of accelerometers can be configured to measure velocity of the user&#39;s body. In some examples, one or more of the plurality of accelerometers  942  can be located on the same layer as one or more of electrodes  932 , piezoelectric sensors  934 , and plurality of temperature sensors  938 . In some examples, the monitoring system can include one or more accelerometers that can be located in areas (e.g., structure of bed  110  illustrated in  FIG. 1 ) of the monitoring system different from the sub-mats. By including one or more separate accelerometers in a location different from the sub-mats, the controller can be capable of including or utilizing the measurement from the one or more separate accelerometers to differentiate the acceleration measurements from the other measurements (e.g., capacitive, electrical, and piezoelectric). 
     In one or more of the exemplary monitoring systems described above, the monitoring system can be configured to measure impedance cardiography (ICG). The ICG measurement can be used to measure the impedance and the total electrical conductivity of the user&#39;s body. The ICG measurement can be used at least partially to measure the heart rate, heart rate variability, respiratory rate, and/or respiratory rate variability. In some examples, one or more electrodes can be configured for an ICG measurement by measuring the change in impedance due to the user&#39;s electrical conductivity. 
       FIG. 10A  illustrates a top view of an exemplary layer included in a mat configured for ICG measurements, and  FIG. 10B  illustrates a corresponding circuit diagram according to examples of the disclosure. System  1099  can include layer  1030  and a plurality of electrodes, such as plurality of electrodes  1032 , plurality of electrodes  1034 , and plurality of electrodes  1036 . Plurality of electrodes  1034  can be located directly under the body of user  1098 . Plurality of electrodes  1036  can be located in the immediate periphery (i.e., adjacent to the electrodes located directly under the body of the user) of the user&#39;s body. Plurality of electrodes  1032  can be located in the periphery of the mat. In some examples, one or more electrodes can be located in both the immediate periphery of the user&#39;s body and the periphery of the mat. Plurality of electrodes  1032 , plurality of electrodes  1036 , or both can be coupled to drive circuitry  1096 . Drive circuitry  1096  can be configured to drive current through the electrodes coupled to it. Plurality of electrodes  1034  can be coupled to sense circuitry  1097 . Sense circuitry  1097  can be configured to measure changes in impedances and transmit the measured impedance values to controller  1095 . 
     In some examples, one or more of plurality of electrodes  1032 , plurality of electrodes  1034 , and plurality of electrodes  1036  can be configured for capacitive, electrical, or impedance measurement during one operation mode and can be configured for another (e.g., capacitive, electrical, or impedance) measurement during another operation mode. In some examples, drive circuitry for capacitive measurements can be the same as drive circuitry for impedance measurements. In some examples, drive circuitry for capacitive measurements can be different from drive circuitry for impedance measurements. In some examples, the frequency for stimulating the electrodes for impedance measurements can be included in a narrow band. In some examples, the frequency for stimulating the electrodes for impedance measurements can include 50 Hz. 
       FIG. 10C  illustrates an exemplary process flow configured for impedance measurement according to examples of the disclosure. In some examples, the monitoring system can operate in multiple modes: one mode (i.e., first mode) for measuring electrical signals and another mode (i.e., second mode) for measuring changes in impedances. During the first mode, one or more electrodes can be configured to measure the user&#39;s electrical signals (step  1052  of process  1050 ). In some examples, the difference in electrical potential between multiple electrodes can be measured. The controller or processor can determine which electrodes are not affected by the user&#39;s electrical signals (step  1054  of process  1050 ) and can disable or disconnect the electrodes to conserve power, for example (step  1056  of process  1050 ). In some examples, the controller can select the electrodes located underneath the user&#39;s body for electrical measurements. The measured electrical signals can be used to form at least a portion of an ECG measurement (step  1058  of process  1050 ). In some examples, the electrical signals can be used to determine the user&#39;s body position, user&#39;s body location and/or location of the user&#39;s heart (step  1060  of process  1050 ). In some examples, step  1052  can be used to form a rough estimate or coarse image of the user&#39;s body position and/or location, and step  1060  can be used to form a more detailed or finer imager of the user&#39;s body position and/or location. The second mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  1062  of process  1050 ). In some examples, the second mode can be repeated after the first mode has been completed (step  1064  of process  1050 ). 
     During the second mode, one or more electrodes can be coupled to drive circuitry. The drive electrodes can be stimulated with a stimulation frequency (step  1066  of process  1050 ). In some examples, the difference in impedance between multiple electrodes can be measured. In some examples, the controller can select the electrodes (e.g., electrodes  1036  illustrated in  FIG. 10A ) located in the immediate periphery of the user&#39;s body as the drive electrodes. In some examples, the controller can select the electrodes (e.g., electrodes  1032  illustrated in  FIG. 10A ) located in the periphery of the mat as the drive electrodes. One or more sense electrodes can be coupled to sense circuitry (e.g., sense circuitry  1097  illustrated in  FIG. 10B ). Sense circuitry can measure the changes in impedances (step  1068  of process  1050 ). The measured impedance values can be used to form at a least a portion of an ICG measurement (step  1070  of process  1050 ). The second mode can be repeated after a predetermined time interval and/or when the user&#39;s body position and/or location change (step  1072  of process  1050 ). In some examples, the second mode can be repeated after the first mode has been completed (step  1074  of process  1050 ). 
     The monitoring system can be configured in one or more measurement modes at a given time. For example, as illustrated in  FIG. 11A , the monitoring system can be configured to time multiplex and cycle between the different measurement modes (e.g., capacitance measurement in t 1 , electrical measurement in t 2 , piezoelectric measurement in t 3 , temperature measurement in t 4 , acceleration measurement in t 5 , and impedance measurement in t 6 ). In some examples, as illustrated in  FIG. 11B , the monitoring system can be configured for one or more measurements responsive to the user&#39;s action. For example, the system can be in a standby mode during t 1 . The user&#39;s body position can move (i.e., user action during time t 2 ), and the monitoring system can be configured for capacitive and electrical measurements, in response to the user action, during time t 3 . In some examples, as illustrated in  FIG. 11C , the monitoring system can be configured for one or more first measurements responsive to one or more changes in conditions. For example, the monitoring system can be configured for periodically measuring the temperature of the room using a control panel (e.g., control panel  140  illustrated in  FIG. 1 ) during standby mode in time t 1 . The monitoring system can determine that the temperature of the room increased above a predetermined threshold during time t 2  (i.e., change in conditions). In response to the change in temperature, the monitoring system can measure the temperature of the local ambient and the user&#39;s body temperature during time t 3 . In some examples, one or more second measurements can be performed conditioned upon the one or more first measurements. If the temperature of the local ambient and/or the user&#39;s body temperature increased to greater than another predetermined threshold, then the user may have transitioned to a different sleep state, which may have affected the user&#39;s respiratory rate and respiratory rate variability. The monitoring system can be configured for piezoelectric measurements during time t 4  to measure the user&#39;s respiratory rate and respiratory rate variability. 
     The monitoring system can be further configured to provide analysis to the user by giving the user feedback regarding the consistency, quality, and duration of the user&#39;s sleep. For example, the system can correlate disruption of one user&#39;s sleep with movement and/or position of another user in the bed. The monitoring system can provide feedback based on the movement and/or position of other users in the bed and can help the users analyze and troubleshoot their sleep. 
     In some examples, the system can correlate disruption of a user&#39;s sleep to one or more room conditions (e.g., room temperature, ambient lights, and environmental sounds). In some examples, the correlation can be used to adjust the temperature of the room through the control system and/or adjust the temperature of the local ambient through active heating or cooling of the mat. In some examples, the monitoring system can determine that the thermal comfort of multiple users can be different, and active heating and/or cooling can be used to accommodate the differences in thermal comfort. In some examples, the monitoring system can communicate one or more non-system components (e.g., window blinds) to enhance the ambient conditions. In some examples, the monitoring system can include one or more actuators in the mat or in communication with the mat. The one or more actuators can be configured to, for example, wake up one or more users based on the user&#39;s sleep state, duration of sleep, and/or time of day. 
     In some examples, the monitoring system can compare present sleep analysis and measurements with historical sleep analysis and measurements. The monitoring system can notice a change in sleep patterns over the course of time and can alert the user or provide feedback. 
     As discussed above, examples of the disclosure can include measuring a plurality of vital signs for one or more users. Additional information can be used to improve the delivery of measured information, analysis, or any other content that may be of interest to the users. In some examples, the measured information, analysis, or other content may include personal information that may uniquely identify the user or may be used to contact or locate the user. Such personal information can include geographic information, demographic information, telephone numbers, email addresses, mailing addresses, home addresses, or other identifying information. In some examples, the use of such personal information can be used to the benefit of the user. For example, the personal information can be used to deliver to the user the measured information, analysis, or other content. Use of personal information can include, but is not limited to, enabling timely and controlled delivery of the content. 
     The disclosure also contemplates that an entity that may be using (e.g., measuring, collecting, analyzing, disclosing, transferring, and/or storing) the personal information will comply with well-established privacy policies and/or privacy practices. These privacy policies and/or privacy practices can be generally recognized as meeting (or exceeding) industry or governmental requirements for private and secure personal information and should be implemented and consistently used. For example, personal information should be collected for legitimate and reasonable purposes and should not be shared (e.g., sold) outside of those purposes. Furthermore, collected personal information should occur only after receiving the informed consent of the user(s). To adhere to privacy policies and/or privacy practices, entities would take any steps necessary for safeguarding and securing outside access to the personal information. In some examples, entities can subject themselves to third party evaluation(s) to certify that the entities are adhering to the well-established, generally recognized privacy policies and/or privacy practices. 
     In some examples, the user(s) can selectively block or restrict access to and/or use of the personal information. The monitoring system can include one or more hardware components and/or one or more software applications to allow the user(s) to selective block or restrict access to and/or use of the personal information. For example, the monitoring system can be configured to allow users to “opt in” or “opt out” of advertisement delivery services when collecting personal information during registration. In some examples, a user can select which information (e.g., home address) to withhold from the advertisement delivery services. 
     Although examples of the disclosure can include monitoring systems and method for measuring vital signs with the use of the user&#39;s personal information, examples of the disclosure can also be capable of one or more functionalities and operation without the user&#39;s personal information. Lack of all or a portion of the personal information may not render the monitor systems and methods inoperable. In some examples, content can be selected and/or delivered to the user based on non-user specific personal (e.g., publicly available) information. 
     A system for determining one or more physiological signals of a user is disclosed. The system can comprise: a first one or more electrodes configured to measure one or more electrical signals; a second one or more electrodes configured to capacitively couple to the first one or more electrodes; and logic configured to: detect a plurality of changes in capacitive coupling between the first one or more electrodes and the second one or more electrodes; determine at least one or more of one or more positions, one or more body motions, and one or more locations of the user based on the plurality of changes in capacitive coupling; detect the one or more electric signals; and determine one or more physiological signals based at least in part on the plurality of changes in capacitive coupling and the one or more electrical signals. Additionally or alternatively, in some examples, the first one or more electrodes are located within a first portion of the system, and the second one or more electrodes are located within a second portion of the system, the second portion is at least partially physically separated from the first portion. Additionally or alternatively, in some examples, the first portion is included in a sheet, and the second portion is included in a blanket. Additionally or alternatively, in some examples, the system further comprises: one or more switches configured to electrically couple at least two of the first one or more electrodes together or at least two of the second one or more together, wherein the logic is further configured to associate a decrease in each of the plurality of changes in capacitive coupling to an increase in gap due to a body of the user physically separating the first one or more first electrodes from the second one or more electrodes. Additionally or alternatively, in some examples, the system further comprises: a first section with a first granularity; a second section with a second granularity capable of being different from the first granularity; and one or more switches configured to couple or decouple the first one or more electrodes together, the second one or more electrodes together, or both to dynamically change one or more of the first and second granularities. 
     A method for determining one or more physiological signals of a user is disclosed. The method can comprise: stimulating a first one or more electrodes; coupling a second one or more electrodes to sense circuitry, the second one or more electrodes configured to capacitively coupling to the first one or more electrodes; detecting a plurality of changes in capacitive coupling at the second one or more electrodes; determining at least one of more of one or more positions, one or more body motions, and one or more locations of the user based on the plurality of changes in capacitive coupling; detecting one or more electrical signals using the second one or more electrodes; and determining one or more physiological signals based on at least in part to the plurality of changes in capacitive coupling and the one or more electrical signals. Additionally or alternatively, in some examples, the method further comprises: forming electrocardiography information from at least the one or more electrical signals, wherein the one or more physiological signals include one or more of a heart rate, heart rate variability, a respiratory rate, and respiratory rate variability. Additionally or alternatively, in some examples, the method further comprises: forming ballistocardiography information from at least the plurality of changes in capacitive coupling, wherein the one or more physiological signals include one or more of a heart rate, heart rate variability, a respiratory rate, and respiratory rate variability. Additionally or alternatively, in some examples, the method further comprises: determining gross motion based on the plurality of changes in capacitive coupling; and determining fine body movements based on the one or more electrical signals. Additionally or alternatively, in some examples, the method further comprises: determining that a change in capacitive coupling between at least one of the first one or more electrodes and at least one of the second one or more electrodes is less than a predetermined threshold; electrically coupling the first one or more electrodes together; stimulating a third one or more electrodes, the third one or more electrodes configured to capacitively couple to the first one or more electrodes; coupling the first one or more electrodes to sense circuitry; and detecting a second plurality of changes in capacitive coupling at the first one or more electrodes. Additionally or alternatively, in some examples, the method further comprises: dynamically changing a granularity of at least a section of the system by electrically coupling or decoupling at least two of the first one or more electrodes, at least two of the second one or more electrodes, or both. Additionally or alternatively, in some examples, the method further comprises: associating a first of the plurality of changes in capacitive coupling, a first of the one or more electrical signals, or both to a first user; and associating a second of the plurality of changes in capacitive coupling, a second of the one or more electrical signals, or both to a second user. Additionally or alternatively, in some examples, the method further comprises: determining one or more temperature values with a plurality of temperature sensors; and refining the determination of the at least one of the one or more positions, one or more body motions, one or more locations, or both of the user based on the one or more temperature values. Additionally or alternatively, in some examples, the method further comprises: determining one or more temperature values with a plurality of temperature sensors; associating a first set of the one or more temperature values to a local ambient; and associating a second set of the one or more temperature values to a temperature of the user. 
     A system for determining one or more physiological signals of a user is disclosed. The system comprises: a plurality of electrodes configured to operate in at least one operation mode, wherein the operation modes comprise: capacitance measurement mode, electrical measurement mode, and impedance measurement; one or more piezoelectric sensors configured to measure one or more mechanical impulses; and logic further configured to: determine one or more values, the one or more values being one or more of changes in capacitive coupling, electrical signals, and impedance using the plurality of electrodes, determine at least one or more of the one or more positions, one or more body motions, and one or more locations of the user based on the one or more values; determine one or more mechanical impulses using the one or more piezoelectric sensors; and determine the one or more physiological signals based at least in part on the one or more values and the one or more mechanical impulses. Additionally or alternatively, in some examples, the one or more piezoelectric sensors include one or more sections of rigid material physically connected with flexible material. Additionally or alternatively, in some examples, the one or more piezoelectric sensors are arranged in one or more rows, one or more columns, or both of piezoelectric sensors, each piezoelectric sensor capable of being independently controlled. Additionally or alternatively, in some examples, the one or more piezoelectric sensors are interleaved with the plurality of electrodes. Additionally or alternatively, in some examples, at least some of the plurality of electrodes are disposed on the one or more piezoelectric sensors. Additionally or alternatively, in some examples, the system further comprises: a plurality of temperature sensors configured to measure one or more temperatures, wherein the plurality of temperature sensors are arranged in one or more rows, one or more columns, or both of temperature sensors, and further wherein the plurality of temperature sensors are interleaved with at least one of the plurality of electrodes and the one or more piezoelectric sensors. Additionally or alternatively, in some examples, the system further comprises: one or more accelerometers configured to measure one or more acceleration values, wherein the one or more accelerometers are arranged in one or more rows, one or more columns, or both of accelerometers, and wherein the one or more accelerometers are interleaved with at least one of the plurality of electrodes, the one or more piezoelectric sensors, and the one or more temperature sensors. Additionally or alternatively, in some examples, the system further comprises: one or more accelerometers configured to measure one or more acceleration values, wherein at least one of the one or more accelerometers is located on a frame of a bed. Additionally or alternatively, in some examples, the system further comprises: one or more actuators configured to provide motion or vibration to the system. Additionally or alternatively, in some examples, the system further comprises: a transceiver configured for communicating with one or more components separate and distinct from the system. Additionally or alternatively, in some examples, the system includes one or more of a sheet, blanket, and pillow. 
     A method for determining one or more physiological signals of a user is disclosed. The method can comprise: stimulating a first one or more electrodes; coupling a second one or more electrodes to sense circuitry, the second one or more electrodes configured to capacitively couple to the first one or more electrodes; detecting a plurality of changes in capacitive coupling at the second one or more electrodes; determining movement information of the user based on the plurality of changes in capacitive coupling, the determination having a first granularity; detecting one or more mechanical impulses with one or more piezoelectric sensors; and determining movement information of the user based on the one or more mechanical impulses, the determination having a second granularity greater than the first granularity. 
     A method of analyzing a sleep of a user is disclosed. The method can comprise: operating a monitoring system in at least two operation modes, the operation modes comprising: capacitance measurement mode, electrical measurement mode, piezoelectric measurement mode, temperature measurement mode, acceleration measurement mode, impedance measurement mode, and standby mode. Additionally or alternatively, in some examples, at least two operation modes are operated concurrently. Additionally or alternatively, in some examples, the operation modes alternate. Additionally or alternatively, in some examples, the method further comprises: detecting one or more changes in conditions associated with the system; and dynamically switching to one or more operating modes based on the one or more changes in conditions. 
     While various examples have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Although examples have been fully described with reference to the accompanying drawings, the various diagrams can depict an exemplary architecture or other configuration for this disclosure, which is done to aid in the understanding of the features and functionality that can be included in the disclosure. The disclosure is not restricted to the illustrated exemplary architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, although the disclosure is described above in terms of various examples and implementations, it should be understood that the various features and functionality described in one or more of the examples are not limited in their applicability to the particular example with which they are described. They instead can be applied alone or in some combination, to one or more of the other examples of the disclosure, whether or not such examples are described, whether or not such features are presented as being part of a described example. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described examples.

Metadata:
Filing Date: 20170811
Publication Date: 20191224
Grant Date: 20191224
Priority Date: 20160812
Inventors: SHAHPARNIA, SHAHROOZ
KLAASSEN, ERNO H.
Assignee: APPLE INC
CPC Classifications: [{"code": "A61B5/1036", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6843", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/4815", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02444", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/113", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/046", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/053", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/01", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2560/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/0247", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/0214", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/02405", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/053", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02438", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/01", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2560/0252", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/7278", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/4815", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/0816", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/046", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/0247", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/1126", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/1102", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/02444", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/113", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/0214", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6843", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/1036", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0252", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/7278", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/1102", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/02438", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/01", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/0816", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/02405", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/04028", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/1126", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/113", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/0247", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/04085", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6843", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/053", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02444", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/4815", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/1036", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/0214", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/046", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2560/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/6892", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6891", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/4806", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02055", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/1102", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/02405", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/0816", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/327", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/282", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/282", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/304", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 59687047