Patent Publication Number: US-2023144677-A1

Title: User interface with integrated sensors

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of, and priority to, U.S. Provisional Pat. Application No. 63/001,273 filed on Mar. 28, 2020, which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to systems and methods for analyzing data related to a user using a respiratory therapy system, and more particularly, to systems and methods for positioning sensors in a user interface worn by a user during use of the respiratory therapy system. 
     BACKGROUND 
     Many individuals suffer from sleep-related disorders, such as insomnia (e.g., difficulty initiating sleep, frequent or prolonged awakenings after initially falling asleep, and an early awakening with an inability to return to sleep), periodic limb movement disorder (PLMD), Obstructive Sleep Apnea (OSA), Cheyne-Stokes Respiration (CSR), respiratory insufficiency, Obesity Hyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease (COPD), Neuromuscular Disease (NMD), hypertension, diabetes, stroke, etc. Many of these sleep related disorders can be treated or managed more effectively if certain data about the is received and analyzed. However, it can be difficult to utilize sensors in a manner that is able to capture the desired data without interrupting the user’s sleep or treatment. Thus, it would be advantageous to locate sensors in the user interface that the user wears during sleep and treatment. The present disclosure is directed to solving these and other problems. 
     SUMMARY 
     According to some implementations of the present disclosure, a user interface of a respiratory therapy system comprises a strap assembly configured to be positioned generally about at least a portion of a head of a user when the user interface is worn by the user; a frame physically and electrically connected to the strap assembly, the frame defining an aperture; a connector having a first portion and a second portion, the first portion being configured to be at least partially positioned within the aperture of the frame such that the connector is physically and electrically connected to the frame; and a sensor coupled to the strap assembly or the frame such that the sensor abuts a target area of the user when the user interface is worn by the user. 
     According to some implementations of the present disclosure, a respiratory therapy device comprises a housing defining an inlet and an outlet; a blower motor positioned within the housing in fluid communication with the inlet and the outlet; a memory device storing machine readable instructions; and a control system including one or more processors configured to execute the machine-readable instructions to cause the blower motor to flow pressurized air out of the outlet, wherein the respiratory therapy device does not include a pressure sensor positioned within the housing and wherein the respiratory therapy device does not include a flow rate sensor positioned within the housing. 
     According to some implementations of the present disclosure, a user interface of a respiratory therapy system comprises a strap assembly configured to be positioned generally about at least a portion of a head of a user when the user interface is worn by the user; a frame physically and electrically connected to the strap assembly, the frame defining an aperture; a cushion coupled to the frame and positioned between the frame and the strap assembly, a connector having a first portion and a second portion, the first portion being configured to be at least partially positioned within the aperture of the frame such that the connector is physically and electrically connected to the frame; and a non-contact sensor positioned within the frame or within the cushion area of the user. 
     The above summary is not intended to represent each implementation or every aspect of the present disclosure. Additional features and benefits of the present disclosure are apparent from the detailed description and figures set forth below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a functional block diagram of a respiratory therapy system, according to some implementations of the present disclosure; 
         FIG.  2    is a perspective view of the respiratory therapy system of  FIG.  1   , a user of the respiratory therapy system, and a bed partner of the user, according to some implementations of the present disclosure; 
         FIG.  3    illustrates an exemplary timeline for a sleep session, according to some implementations of the present disclosure; 
         FIG.  4    illustrates an exemplary hypnogram associated with the sleep session of  FIG.  3   , according to some implementations of the present disclosure; 
         FIG.  5 A  is a perspective view of a first implementation of a user interface of the respiratory therapy system of  FIG.  1   , according to some implementations of the present disclosure; 
         FIG.  5 B  is a perspective exploded view of the user interface of  FIG.  3 A , according to some implementations of the present disclosure; 
         FIG.  6 A  is a perspective view of the alignment of electrical contacts of a connector and a frame of the user interface of  FIG.  5 A , according to some implementations of the present disclosure; 
         FIG.  6 B  is a magnified view of the electrical contacts of the frame of the user interface of  FIG.  5 A , according to some implementations of the present disclosure; 
         FIG.  6 C  is a cross-sectional view of the electrical connection between the connector and the frame of the user interface of  FIG.  5 A  prior to the connector being inserted into the frame, according to some implementations of the present disclosure; 
         FIG.  6 D  is a cross-sectional view of the electrical connection between the connector and the frame of the user interface of  FIG.  5 A  after the connector is inserted into the frame, according to some implementations of the present disclosure; 
         FIG.  7    is a perspective view of the electrical connection between the frame and a strap of the user interface of  FIG.  5 A , according to some implementations of the present disclosure; and 
         FIG.  8    is a perspective view of a user wearing the user interface of  FIG.  5 A , according to some implementations of the present disclosure. 
         FIG.  9 A  is a perspective view of a second implementation of a user interface of the respiratory therapy system of  FIG.  1   , according to some implementations of the present disclosure. 
         FIG.  9 B  is an exploded view of the user interface of  FIG.  9 A , according to some implementations of the present disclosure. 
     
    
    
     While the present disclosure is susceptible to various modifications and alternative forms, specific implementations and embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that it is not intended to limit the present disclosure to the particular forms disclosed, but on the contrary, the present disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims. 
     DETAILED DESCRIPTION 
     Many individuals suffer from sleep-related and/or respiratory-related disorders. Examples of sleep-related and/or respiratory-related disorders include Periodic Limb Movement Disorder (PLMD), Restless Leg Syndrome (RLS), Sleep-Disordered Breathing (SDB), Obstructive Sleep Apnea (OSA), Central Sleep Apnea (CSA), other types of apneas, Cheyne-Stokes Respiration (CSR), respiratory insufficiency, Obesity Hyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease (COPD), Neuromuscular Disease (NMD), chest wall disorders, and rapid eye movement (REM) behavior disorder, also referred to as RBD. 
     Obstructive Sleep Apnea (OSA) is a form of Sleep Disordered Breathing (SDB), and is characterized by events including occlusion or obstruction of the upper air passage during sleep resulting from a combination of an abnormally small upper airway and the normal loss of muscle tone in the region of the tongue, soft palate and posterior oropharyngeal wall. 
     Central Sleep Apnea (CSA) is another form of SDB that results when the brain temporarily stops sending signals to the muscles that control breathing. More generally, an apnea generally refers to the cessation of breathing caused by blockage of the air or the stopping of the breathing function. Typically, the individual will stop breathing for between about 15 seconds and about 30 seconds during an obstructive sleep apnea event. Mixed sleep apnea is another form of SDB that is a combination of OSA and CSA. 
     Other types of apneas include hypopnea, hyperpnea, and hypercapnia. Hypopnea is generally characterized by slow or shallow breathing caused by a narrowed airway, as opposed to a blocked airway. Hyperpnea is generally characterized by an increase depth and/or rate of breathing. Hypercapnia is generally characterized by elevated or excessive carbon dioxide in the bloodstream, typically caused by inadequate respiration. 
     Cheyne-Stokes Respiration (CSR) is another form of SDB. CSR is a disorder of a patient’s respiratory controller in which there are rhythmic alternating periods of waxing and waning ventilation known as CSR cycles. CSR is characterized by repetitive de-oxygenation and re-oxygenation of the arterial blood. 
     Obesity Hyperventilation Syndrome (OHS) is defined as the combination of severe obesity and awake chronic hypercapnia, in the absence of other known causes for hypoventilation. Symptoms include dyspnea, morning headache and excessive daytime sleepiness. 
     Chronic Obstructive Pulmonary Disease (COPD) encompasses any of a group of lower airway diseases that have certain characteristics in common, such as increased resistance to air movement, extended expiratory phase of respiration, and loss of the normal elasticity of the lung. 
     Neuromuscular Disease (NMD) encompasses many diseases and ailments that impair the functioning of the muscles either directly via intrinsic muscle pathology, or indirectly via nerve pathology. Chest wall disorders are a group of thoracic deformities that result in inefficient coupling between the respiratory muscles and the thoracic cage. 
     These and other disorders are characterized by particular events (e.g., snoring, an apnea, a hypopnea, a restless leg, a sleeping disorder, choking, an increased heart rate, labored breathing, an asthma attack, an epileptic episode, a seizure, or any combination thereof) that occur when the individual is sleeping. 
     The Apnea-Hypopnea Index (AHI) is an index used to indicate the severity of sleep apnea during a sleep session. The AHI is calculated by dividing the number of apnea and/or hypopnea events experienced by the user during the sleep session by the total number of hours of sleep in the sleep session. The event can be, for example, a pause in breathing that lasts for at least 10 seconds. An AHI that is less than 5 is considered normal. An AHI that is greater than or equal to 5, but less than 15 is considered indicative of mild sleep apnea. An AHI that is greater than or equal to 15, but less than 30 is considered indicative of moderate sleep apnea. An AHI that is greater than or equal to 30 is considered indicative of severe sleep apnea. In children, an AHI that is greater than 1 is considered abnormal. Sleep apnea can be considered “controlled” when the AHI is normal, or when the AHI is normal or mild. The AHI can also be used in combination with oxygen desaturation levels to indicate the severity of Obstructive Sleep Apnea. 
     A wide variety of types of data can be used to monitor the health of individuals having any of the above types of sleep-related and/or respiratory disorders (or other disorders). However, it is often difficult to collect accurate data in a manner that does not interrupt or disturb the user’s sleep, or interfere with any treatment the user may be undergoing during sleep. Thus, it is advantageous to utilize a system for treatment that includes various sensors to generate and collect data, without disturbing the user, the user’s sleep, or the user’s treatment. 
     Referring to  FIG.  1   , a system  100 , according to some implementations of the present disclosure, is illustrated. The system  100  is for providing a variety of different sensors related to a user’s use of a respiratory therapy system, among other uses. The system  100  includes a control system  110 , a memory device  114 , an electronic interface  119 , one or more sensors  130 , and one or more external devices  170 . In some implementation, the system  100  further includes a respiratory therapy system  120  that includes a respiratory therapy device  122 . 
     The control system  110  includes one or more processors  112  (hereinafter, processor  112 ). The control system  110  is generally used to control (e.g., actuate) the various components of the system  100  and/or analyze data obtained and/or generated by the components of the system  100 . The processor  112  can be a general or special purpose processor or microprocessor. While one processor  112  is shown in  FIG.  1   , the control system  110  can include any suitable number of processors (e.g., one processor, two processors, five processors, ten processors, etc.) that can be in a single housing, or located remotely from each other. The control system  110  (or any other control system) or a portion of the control system  110  such as the processor  112  (or any other processor(s) or portion(s) of any other control system), can be used to carry out one or more steps of any of the methods described and/or claimed herein. The control system  110  can be coupled to and/or positioned within, for example, a housing of the external device  170 , and/or within a housing of one or more of the sensors  130 . The control system  110  can be centralized (within one such housing) or decentralized (within two or more of such housings, which are physically distinct). In such implementations including two or more housings containing the control system  110 , such housings can be located proximately and/or remotely from each other. 
     The memory device  114  stores machine-readable instructions that are executable by the processor  112  of the control system  110 . The memory device  114  can be any suitable computer readable storage device or media, such as, for example, a random or serial access memory device, a hard drive, a solid state drive, a flash memory device, etc. While one memory device  114  is shown in  FIG.  1   , the system  100  can include any suitable number of memory devices  114  (e.g., one memory device, two memory devices, five memory devices, ten memory devices, etc.). The memory device  114  can be coupled to and/or positioned within a housing of a respiratory therapy device  122  of the respiratory therapy system  120 , within a housing of the external device  170 , within a housing of one or more of the sensors  130 , or any combination thereof. Like the control system  110 , the memory device  114  can be centralized (within one such housing) or decentralized (within two or more of such housings, which are physically distinct). 
     In some implementations, the memory device  114  ( FIG.  1   ) stores a user profile associated with the user. The user profile can include, for example, demographic information associated with the user, biometric information associated with the user, medical information associated with the user, self-reported user feedback, sleep parameters associated with the user (e.g., sleep-related parameters recorded from one or more earlier sleep sessions), or any combination thereof. The demographic information can include, for example, information indicative of an age of the user, a gender of the user, a race of the user, a family medical history (such as a family history of insomnia or sleep apnea), an employment status of the user, an educational status of the user, a socioeconomic status of the user, or any combination thereof. The medical information can include, for example, information indicative of one or more medical conditions associated with the user, medication usage by the user, or both. The medical information data can further include a multiple sleep latency test (MSLT) result or score and/or a Pittsburgh Sleep Quality Index (PSQI) score or value. The self-reported user feedback can include information indicative of a self-reported subjective sleep score (e.g., poor, average, excellent), a self-reported subjective stress level of the user, a self-reported subjective fatigue level of the user, a self-reported subjective health status of the user, a recent life event experienced by the user, or any combination thereof. 
     The electronic interface  119  is configured to receive data (e.g., physiological data and/or acoustic data) from the one or more sensors  130  such that the data can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . The electronic interface  119  can communicate with the one or more sensors  130  using a wired connection or a wireless connection (e.g., using an RF communication protocol, a WiFi communication protocol, a Bluetooth communication protocol, an IR communication protocol, over a cellular network, over any other optical communication protocol, etc.). The electronic interface  119  can include an antenna, a receiver (e.g., an RF receiver), a transmitter (e.g., an RF transmitter), a transceiver, or any combination thereof. The electronic interface  119  can also include one more processors and/or one more memory devices that are the same as, or similar to, the processor  112  and the memory device  114  described herein. In some implementations, the electronic interface  119  is coupled to or integrated in the external device  170 . In other implementations, the electronic interface  119  is coupled to or integrated (e.g., in a housing) with the control system  110  and/or the memory device  114 . 
     As noted above, in some implementations, the system  100  optionally includes a respiratory therapy system  120  (also referred to as a respiratory pressure therapy system). The respiratory therapy system  120  can include a respiratory therapy device  122  (also referred to as a respiratory pressure therapy device), a user interface  124 , a conduit  126  (also referred to as a tube or an air circuit), a display device  128 , a humidification tank  129 , or any combination thereof. In some implementations, the control system  110 , the memory device  114 , the display device  128 , one or more of the sensors  130 , and the humidification tank  129  are part of the respiratory therapy device  122 . Respiratory pressure therapy refers to the application of a supply of air to an entrance to a user’s airways at a controlled target pressure that is nominally positive with respect to atmosphere throughout the user’s breathing cycle (e.g., in contrast to negative pressure therapies such as the tank ventilator or cuirass). The respiratory therapy system  120  is generally used to treat individuals suffering from one or more sleep-related respiratory disorders (e.g., obstructive sleep apnea, central sleep apnea, or mixed sleep apnea), other respiratory disorders such as COPD, or other disorders leading to respiratory insufficiency, that may manifest either during sleep or wakefulness. 
     The respiratory therapy device  122  is generally used to generate pressurized air that is delivered to a user (e.g., using one or more motors that drive one or more compressors). In some implementations, the respiratory therapy device  122  generates continuous constant air pressure that is delivered to the user. In other implementations, the respiratory therapy device  122  generates two or more predetermined pressures (e.g., a first predetermined air pressure and a second predetermined air pressure). In still other implementations, the respiratory therapy device  122  is configured to generate a variety of different air pressures within a predetermined range. For example, the respiratory therapy device  122  can deliver at least about 6 cm H 2 O, at least about 10 cm H 2 O, at least about 20 cm H 2 O, between about 6 cm H 2 O and about 10 cm H 2 O, between about 7 cm H 2 O and about 12 cm H 2 O, etc. The respiratory therapy device  122  can also deliver pressurized air at a predetermined flow rate between, for example, about -20 L/min and about 150 L/min, while maintaining a positive pressure (relative to the ambient pressure). In some implementations, the control system  110 , the memory device  114 , the electronic interface  119 , or any combination thereof can be coupled to and/or positioned within a housing of the respiratory therapy device  122 . 
     The user interface  124  engages a portion of the user’s face and delivers pressurized air from the respiratory therapy device  122  to the user’s airway to aid in preventing the airway from narrowing and/or collapsing during sleep. This may also increase the user’s oxygen intake during sleep. Depending upon the therapy to be applied, the user interface  124  may form a seal, for example, with a region or portion of the user’s face, to facilitate the delivery of gas at a pressure at sufficient variance with ambient pressure to effect therapy, for example, at a positive pressure of about 10 cm H 2 O relative to ambient pressure. For other forms of therapy, such as the delivery of oxygen, the user interface may not include a seal sufficient to facilitate delivery to the airways of a supply of gas at a positive pressure of about 10 cm H 2 O. 
     In some implementations, the user interface  124  is or includes a facial mask that covers the nose and mouth of the user (as shown, for example, in  FIG.  2   ). Alternatively, the user interface  124  is or includes a nasal mask that provides air to the nose of the user or a nasal pillow mask that delivers air directly to the nostrils of the user. The user interface  124  can include a strap assembly that has a plurality of straps (e.g., including hook and loop fasteners) for positioning and/or stabilizing the user interface  124  on a portion of the user interface  124  on a desired location of the user (e.g., the face), and a conformal cushion (e.g., silicone, plastic, foam, etc.) that aids in providing an air-tight seal between the user interface  124  and the user. The user interface  124  can also include one or more vents  125  for permitting the escape of carbon dioxide and other gases exhaled by the user. In other implementations, the user interface  124  includes a mouthpiece (e.g., a night guard mouthpiece molded to conform to the user’s teeth, a mandibular repositioning device, etc.). 
     The conduit  126  allows the flow of air between two components of a respiratory therapy system  120 , such as the respiratory therapy device  122  and the user interface  124 . In some implementations, there can be separate limbs of the conduit for inhalation and exhalation. In other implementations, a single limb conduit is used for both inhalation and exhalation. Generally, the respiratory therapy system  120  forms an air pathway that extends between a motor of the respiratory therapy device  122  and the user and/or the user’s airway. Thus, the air pathway generally includes at least a motor of the respiratory therapy device  122 , the user interface  124 , and the conduit  126 . 
     One or more of the respiratory therapy device  122 , the user interface  124 , the conduit  126 , the display device  128 , and the humidification tank  129  can contain one or more sensors (e.g., a pressure sensor, a flow rate sensor, or more generally any of the other sensors  130  described herein). These one or more sensors can be used, for example, to measure the air pressure and/or flow rate of pressurized air supplied by the respiratory therapy device  122 . 
     The display device  128  is generally used to display image(s) including still images, video images, or both and/or information regarding the respiratory therapy device  122 . For example, the display device  128  can provide information regarding the status of the respiratory therapy device  122  (e.g., whether the respiratory therapy device  122  is on/off, the pressure of the air being delivered by the respiratory therapy device  122 , the temperature of the air being delivered by the respiratory therapy device  122 , etc.) and/or other information (e.g., a sleep score or a therapy score (also referred to as a myAir™ score, such as described in WO 2016/061629, which is hereby incorporated by reference herein in its entirety), the current date/time, personal information for the user, etc.). In some implementations, the display device  128  acts as a human-machine interface (HMI) that includes a graphic user interface (GUI) configured to display the image(s) as an input interface. The display device  128  can be an LED display, an OLED display, an LCD display, or the like. The input interface can be, for example, a touchscreen or touch-sensitive substrate, a mouse, a keyboard, or any sensor system configured to sense inputs made by a human user interacting with the respiratory therapy device  122 . 
     The humidification tank  129  is coupled to or integrated in the respiratory therapy device  122  and includes a reservoir of water that can be used to humidify the pressurized air delivered from the respiratory therapy device  122 . The respiratory therapy device  122  can include a heater to heat the water in the humidification tank  129  in order to humidify the pressurized air provided to the user. Additionally, in some implementations, the conduit  126  can also include a heating element (e.g., coupled to and/or imbedded in the conduit  126 ) that heats the pressurized air delivered to the user. In other implementations, the respiratory therapy device  122  or the conduit  126  can include a waterless humidifier. The waterless humidifier can incorporate sensors that interface with other sensor positioned elsewhere in the system  100 . 
     The respiratory therapy system  120  can be used, for example, as a ventilator or a positive airway pressure (PAP) system, such as a continuous positive airway pressure (CPAP) system, an automatic positive airway pressure system (APAP), a bi-level or variable positive airway pressure system (BPAP or VPAP), or any combination thereof. The CPAP system delivers a predetermined air pressure (e.g., determined by a sleep physician) to the user. The APAP system automatically varies the air pressure delivered to the user based at least in part on, for example, respiration data associated with the user. The BPAP or VPAP system is configured to deliver a first predetermined pressure (e.g., an inspiratory positive airway pressure or IPAP) and a second predetermined pressure (e.g., an expiratory positive airway pressure or EPAP) that is lower than the first predetermined pressure. 
     Referring to  FIG.  2   , a portion of the system  100  ( FIG.  1   ), according to some implementations, is illustrated. A user  210  of the respiratory therapy system  120  and a bed partner  220  are located in a bed  230  and are laying on a mattress  232 . The user interface  124  (e.g., a full facial mask) can be worn by the user  210  during a sleep session. The user interface  124  is fluidly coupled and/or connected to the respiratory therapy device  122  via the conduit  126 . In turn, the respiratory therapy device  122  delivers pressurized air to the user  210  via the conduit  126  and the user interface  124  to increase the air pressure in the throat of the user  210  to aid in preventing the airway from closing and/or narrowing during sleep. The respiratory therapy device  122  can include the display device  128 , which can allow the user to interact with the respiratory therapy device  122 . The respiratory therapy device  122  can also include the humidification tank  129 , which stores the water used to humidify the pressurized air. The respiratory therapy device  122  can be positioned on a nightstand  234  that is directly adjacent to the bed  230  as shown in  FIG.  2   , or more generally, on any surface or structure that is generally adjacent to the bed  230  and/or the user  210 . The user can also wear the blood pressure device  180  and the activity tracker  182  while lying on the mattress  232  in the bed  230 . 
     Referring back to  FIG.  1   , the one or more sensors  130  of the system  100  include a pressure sensor  132 , a flow rate sensor  134 , temperature sensor  136 , a motion sensor  138 , a microphone  140 , a speaker  142 , a radio-frequency (RF) receiver  146 , an RF transmitter  148 , a camera  150 , an infrared (IR) sensor  152 , a photoplethysmogram (PPG) sensor  154 , an electrocardiogram (ECG) sensor  156 , an electroencephalography (EEG) sensor  158 , a capacitive sensor  160 , a force sensor  162 , a strain gauge sensor  164 , an electromyography (EMG) sensor  166 , an oxygen sensor  168 , an analyte sensor  174 , a moisture sensor  176 , a light detection and ranging (LiDAR) sensor  178 , or any combination thereof. Generally, each of the one or sensors  130  are configured to output sensor data that is received and stored in the memory device  114  or one or more other memory devices. The sensors  130  can also include, an electrooculography (EOG) sensor, a peripheral oxygen saturation (SpO 2 ) sensor, a galvanic skin response (GSR) sensor, a carbon dioxide (CO 2 ) sensor, or any combination thereof. 
     While the one or more sensors  130  are shown and described as including each of the pressure sensor  132 , the flow rate sensor  134 , the temperature sensor  136 , the motion sensor  138 , the microphone  140 , the speaker  142 , the RF receiver  146 , the RF transmitter  148 , the camera  150 , the IR sensor  152 , the PPG sensor  154 , the ECG sensor  156 , the EEG sensor  158 , the capacitive sensor  160 , the force sensor  162 , the strain gauge sensor  164 , the EMG sensor  166 , the oxygen sensor  168 , the analyte sensor  174 , the moisture sensor  176 , and the LiDAR sensor  178 , more generally, the one or more sensors  130  can include any combination and any number of each of the sensors described and/or shown herein. 
     The one or more sensors  130  can be used to generate, for example physiological data, acoustic data, or both, that is associated with a user of the respiratory therapy system  120  (such as the user  210  of  FIG.  2   ), the respiratory therapy system  120 , both the user and the respiratory therapy system  120 , or other entities, objects, activities, etc. Physiological data generated by one or more of the sensors  130  can be used by the control system  110  to determine a sleep-wake signal associated with the user during the sleep session and one or more sleep-related parameters. The sleep-wake signal can be indicative of one or more sleep stages and/or sleep states, including sleep, wakefulness, relaxed wakefulness, micro-awakenings, or distinct sleep stages including a rapid eye movement (REM) stage (which can include both a typical REM stage and an atypical REM stage), a first non-REM stage (often referred to as “N1”), a second non-REM stage (often referred to as “N2”), a third non-REM stage (often referred to as “N3”), or any combination thereof. Methods for determining sleep stages and/or sleep states from physiological data generated by one or more of the sensors, such as sensors  130 , are described in, for example, WO 2014/047310, US 2014/0088373, WO 2017/132726, WO 2019/122413, and WO 2019/122414, each of which is hereby incorporated by reference herein in its entirety. 
     The sleep-wake signal can also be timestamped to indicate a time that the user enters the bed, a time that the user exits the bed, a time that the user attempts to fall asleep, etc. The sleep-wake signal can be measured one or more of the sensors  130  during the sleep session at a predetermined sampling rate, such as, for example, one sample per second, one sample per 30 seconds, one sample per minute, etc. Examples of the one or more sleep-related parameters that can be determined for the user during the sleep session based at least in part on the sleep-wake signal include a total time in bed, a total sleep time, a total wake time, a sleep onset latency, a wake-after-sleep-onset parameter, a sleep efficiency, a fragmentation index, an amount of time to fall asleep, a consistency of breathing rate, a fall asleep time, a wake time, a rate of sleep disturbances, a number of movements, or any combination thereof. 
     Physiological data and/or acoustic data generated by the one or more sensors  130  can also be used to determine a respiration signal associated with the user during a sleep session. the respiration signal is generally indicative of respiration or breathing of the user during the sleep session. The respiration signal can be indicative of, for example, a respiration rate, a respiration rate variability, an inspiration amplitude, an expiration amplitude, an inspiration-expiration amplitude ratio, an inspiration-expiration duration ratio, a number of events per hour, a pattern of events, pressure settings of the respiratory therapy device  122 , or any combination thereof. The event(s) can include snoring, apneas, central apneas, obstructive apneas, mixed apneas, hypopneas, a mask leak (e.g., from the user interface  124 ), a restless leg, a sleeping disorder, choking, an increased heart rate, a heart rate variation, labored breathing, an asthma attack, an epileptic episode, a seizure, a fever, a cough, a sneeze, a snore, a gasp, the presence of an illness such as the common cold or the flu, an elevated stress level, etc. 
     The pressure sensor  132  outputs pressure data that can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . In some implementations, the pressure sensor  132  is an air pressure sensor (e.g., barometric pressure sensor) that generates sensor data indicative of the respiration (e.g., inhaling and/or exhaling) of the user of the respiratory therapy system  120  and/or ambient pressure. In such implementations, the pressure sensor  132  can be coupled to or integrated in the respiratory therapy device  122 . The pressure sensor  132  can be, for example, a capacitive sensor, an electromagnetic sensor, an inductive sensor, a resistive sensor, a piezoelectric sensor, a strain-gauge sensor, an optical sensor, a potentiometric sensor, or any combination thereof. In one example, the pressure sensor  132  can be used to determine a blood pressure of the user. 
     The flow rate sensor  134  outputs flow rate data that can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . In some implementations, the flow rate sensor  134  is used to determine an air flow rate from the respiratory therapy device  122 , an air flow rate through the conduit  126 , an air flow rate through the user interface  124 , or any combination thereof. In such implementations, the flow rate sensor  134  can be coupled to or integrated in the respiratory therapy device  122 , the user interface  124 , or the conduit  126 . The flow rate sensor  134  can be a mass flow rate sensor such as, for example, a rotary flow meter (e.g., Hall effect flow meters), a turbine flow meter, an orifice flow meter, an ultrasonic flow meter, a hot wire sensor, a vortex sensor, a membrane sensor, or any combination thereof. 
     The temperature sensor  136  outputs temperature data that can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . In some implementations, the temperature sensor  136  generates temperatures data indicative of a core body temperature of the user, a skin temperature of the user, a temperature of the air flowing from the respiratory therapy device  122  and/or through the conduit  126 , a temperature in the user interface  124 , an ambient temperature, or any combination thereof. The temperature sensor  136  can be, for example, a thermocouple sensor, a thermistor sensor, a silicon band gap temperature sensor or semiconductor-based sensor, a resistance temperature detector, or any combination thereof. 
     The motion sensor  138  outputs motion data that can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . The motion sensor  138  can be used to detect movement of the user during the sleep session, and/or detect movement of any of the components of the respiratory therapy system  120 , such as the respiratory therapy device  122 , the user interface  124 , or the conduit  126 . The motion sensor  138  can include one or more inertial sensors, such as accelerometers, gyroscopes, and magnetometers. The motion sensor  138  can be used to detect motion or acceleration associated with arterial pulses, such as pulses in or around the face of the user and proximal to the user interface  124 , and configured to detect features of the pulse shape, speed, amplitude, or volume. 
     The microphone  140  outputs acoustic data that can be stored in the memory device  114  and/or analyzed by the processor  112  of the control system  110 . The acoustic data generated by the microphone  140  is reproducible as one or more sound(s) during a sleep session (e.g., sounds from the user) to determine (e.g., using the control system  110 ) one or more sleep-related parameters, as described in further detail herein. The acoustic data from the microphone  140  can also be used to identify (e.g., using the control system  110 ) an event experienced by the user during the sleep session, as described in further detail herein. In other implementations, the acoustic data from the microphone  140  is representative of noise associated with the respiratory therapy system  120 . The microphone  140  can be coupled to or integrated in the respiratory therapy system  120  (or the system  100 ) generally in any configuration. For example, the microphone  140  can be disposed inside the respiratory therapy device  122 , the user interface  124 , the conduit  126 , or other components. The microphone  140  can also be positioned adjacent to or coupled to the outside of the respiratory therapy device  122 , the outside of the user interface  124 , the outside of the conduit  126 , or outside of any other components. The microphone  140  could also be a component of the external device  170  (e.g., the microphone  140  is a microphone of a smart phone). The microphone  140  can be integrated into the user interface  124 , the conduit  126 , the respiratory therapy device  122 , or any combination thereof. In general, the microphone  140  can be located at any point within or adjacent to the air pathway of the respiratory therapy system  120 , which includes at least the motor of the respiratory therapy device  122 , the user interface  124 , and the conduit  126 . Thus, the air pathway can also be referred to as the acoustic pathway. 
     The speaker  142  outputs sound waves that are audible to the user. The speaker  142  can be used, for example, as an alarm clock or to play an alert or message to the user (e.g., in response to an event). In some implementations, the speaker  142  can be used to communicate the acoustic data generated by the microphone  140  to the user. The speaker  142  can be coupled to or integrated in the respiratory therapy device  122 , the user interface  124 , the conduit  126 , or the external device  170 . 
     The microphone  140  and the speaker  142  can be used as separate devices. In some implementations, the microphone  140  and the speaker  142  can be combined into an acoustic sensor  141  (e.g., a SONAR sensor), as described in, for example, WO 2018/050913 and WO 2020/104465, each of which is hereby incorporated by reference herein in its entirety. In such implementations, the speaker  142  generates or emits sound waves at a predetermined interval and/or frequency, and the microphone  140  detects the reflections of the emitted sound waves from the speaker  142 . The sound waves generated or emitted by the speaker  142  have a frequency that is not audible to the human ear (e.g., below 20 Hz or above around 18 kHz) so as not to disturb the sleep of the user or a bed partner of the user (such as bed partner  220  in  FIG.  2   ). Based at least in part on the data from the microphone  140  and/or the speaker  142 , the control system  110  can determine a location of the user and/or one or more of the sleep-related parameters described in herein, such as, for example, a respiration signal, a respiration rate, an inspiration amplitude, an expiration amplitude, an inspiration-expiration ratio, a number of events per hour, a pattern of events, a sleep stage, pressure settings of the respiratory therapy device  122 , or any combination thereof. In this context, a SONAR sensor may be understood to concern an active acoustic sensing, such as by generating/transmitting ultrasound or low frequency ultrasound sensing signals (e.g., in a frequency range of about 17-23 kHz, 18-22 kHz, or 17-18 kHz, for example), through the air. Such a system may be considered in relation to WO 2018/050913 and WO 2020/104465 mentioned above. In some implementations, the speaker  142  is a bone conduction speaker. In some implementations, the one or more sensors  130  include (i) a first microphone that is the same or similar to the microphone  140 , and is integrated into the acoustic sensor  141  and (ii) a second microphone that is the same as or similar to the microphone  140 , but is separate and distinct from the first microphone that is integrated into the acoustic sensor  141 . 
     The RF transmitter  148  generates and/or emits radio waves having a predetermined frequency and/or a predetermined amplitude (e.g., within a high frequency band, within a low frequency band, long wave signals, short wave signals, etc.). The RF receiver  146  detects the reflections of the radio waves emitted from the RF transmitter  148 , and this data can be analyzed by the control system  110  to determine a location of the user and/or one or more of the sleep-related parameters described herein. An RF receiver (either the RF receiver  146  and the RF transmitter  148  or another RF pair) can also be used for wireless communication between the control system  110 , the respiratory therapy device  122 , the one or more sensors  130 , the external device  170 , or any combination thereof. While the RF receiver  146  and RF transmitter  148  are shown as being separate and distinct elements in  FIG.  1   , in some implementations, the RF receiver  146  and RF transmitter  148  are combined as a part of an RF sensor  147  (e.g., a RADAR sensor). In some such implementations, the RF sensor  147  includes a control circuit. The specific format of the RF communication could be WiFi, Bluetooth, etc. 
     In some implementations, the RF sensor  147  is a part of a mesh system. One example of a mesh system is a WiFi mesh system, which can include mesh nodes, mesh router(s), and mesh gateway(s), each of which can be mobile/movable or fixed. In such implementations, the WiFi mesh system includes a WiFi router and/or a WiFi controller and one or more satellites (e.g., access points), each of which include an RF sensor that the is the same as, or similar to, the RF sensor  147 . The WiFi router and satellites continuously communicate with one another using WiFi signals. The WiFi mesh system can be used to generate motion data based at least in part on changes in the WiFi signals (e.g., differences in received signal strength) between the router and the satellite(s) due to an object or person moving partially obstructing the signals. The motion data can be indicative of motion, breathing, heart rate, gait, falls, behavior, etc., or any combination thereof. 
     The camera  150  outputs image data reproducible as one or more images (e.g., still images, video images, thermal images, or a combination thereof) that can be stored in the memory device  114 . The image data from the camera  150  can be used by the control system  110  to determine one or more of the sleep-related parameters described herein. For example, the image data from the camera  150  can be used to identify a location of the user, to determine a time when the user enters the user’s bed (such as bed  230  in  FIG.  2   ), and to determine a time when the user exits the bed  230 . The camera  150  can also be used to track eye movements, pupil dilation (if one or both of the user’s eyes are open), blink rate, or any changes during REM sleep. The camera  150  can also be used to track the position of the user, which can impact the duration and/or severity of apneic episodes in users with positional obstructive sleep apnea. 
     The IR sensor  152  outputs infrared image data reproducible as one or more infrared images (e.g., still images, video images, or both) that can be stored in the memory device  114 . The infrared data from the IR sensor  152  can be used to determine one or more sleep-related parameters during the sleep session, including a temperature of the user and/or movement of the user. The IR sensor  152  can also be used in conjunction with the camera  150  when measuring the presence, location, and/or movement of the user. The IR sensor  152  can detect infrared light having a wavelength between about 700 nm and about 1 mm, for example, while the camera  150  can detect visible light having a wavelength between about 380 nm and about 740 nm. 
     The IR sensor  152  outputs infrared image data reproducible as one or more infrared images (e.g., still images, video images, or both) that can be stored in the memory device  114 . The infrared data from the IR sensor  152  can be used to determine one or more sleep-related parameters during the sleep session, including a temperature of the user and/or movement of the user. The IR sensor  152  can also be used in conjunction with the camera  150  when measuring the presence, location, and/or movement of the user. The IR sensor  152  can detect infrared light having a wavelength between about 700 nm and about 1 mm, for example, while the camera  150  can detect visible light having a wavelength between about 380 nm and about 740 nm. 
     The PPG sensor  154  outputs physiological data associated with the user that can be used to determine one or more sleep-related parameters, such as, for example, a heart rate, a heart rate pattern, a heart rate variability, a cardiac cycle, respiration rate, an inspiration amplitude, an expiration amplitude, an inspiration-expiration ratio, estimated blood pressure parameter(s), or any combination thereof. The PPG sensor  154  can be worn by the user, embedded in clothing and/or fabric that is worn by the user, embedded in and/or coupled to the user interface  124  and/or its associated headgear (e.g., straps, etc.), etc. 
     The ECG sensor  156  outputs physiological data associated with electrical activity of the heart of the user. In some implementations, the ECG sensor  156  includes one or more electrodes that are positioned on or around a portion of the user during the sleep session. The physiological data from the ECG sensor  156  can be used, for example, to determine one or more of the sleep-related parameters described herein. 
     The EEG sensor  158  outputs physiological data associated with electrical activity of the brain of the user. In some implementations, the EEG sensor  158  includes one or more electrodes that are positioned on or around the scalp of the user during the sleep session. The physiological data from the EEG sensor  158  can be used, for example, to determine a sleep stage and/or a sleep state of the user at any given time during the sleep session. In some implementations, the EEG sensor  158  can be integrated in the user interface  124  and/or the associated headgear (e.g., straps, etc.). 
     The capacitive sensor  160 , the force sensor  162 , and the strain gauge sensor  164  output data that can be stored in the memory device  114  and used by the control system  110  to determine one or more of the sleep-related parameters described herein. The EMG sensor  166  outputs physiological data associated with electrical activity produced by one or more muscles. The oxygen sensor  168  outputs oxygen data indicative of an oxygen concentration of gas (e.g., in the conduit  126  or at the user interface  124 ). The oxygen sensor  168  can be, for example, an ultrasonic oxygen sensor, an electrical oxygen sensor, a chemical oxygen sensor, an optical oxygen sensor, or any combination thereof. In some implementations, the one or more sensors  130  also include a galvanic skin response (GSR) sensor, a blood flow sensor, a respiration sensor, a pulse sensor, a sphygmomanometer sensor, an oximetry sensor, or any combination thereof. 
     The analyte sensor  174  can be used to detect the presence of an analyte in the exhaled breath of the user. The data output by the analyte sensor  174  can be stored in the memory device  114  and used by the control system  110  to determine the identity and concentration of any analytes in the user’s breath. In some implementations, the analyte sensor  174  is positioned near a mouth of the user to detect analytes in breath exhaled from the user’s mouth. For example, when the user interface  124  is a facial mask that covers the nose and mouth of the user, the analyte sensor  174  can be positioned within the facial mask to monitor the user mouth breathing. In other implementations, such as when the user interface  124  is a nasal mask or a nasal pillow mask, the analyte sensor  174  can be positioned near the nose of the user to detect analytes in breath exhaled through the user’s nose. In still other implementations, the analyte sensor  174  can be positioned near the user’s mouth when the user interface  124  is a nasal mask or a nasal pillow mask. In this implementation, the analyte sensor  174  can be used to detect whether any air is inadvertently leaking from the user’s mouth. In some implementations, the analyte sensor  174  is a volatile organic compound (VOC) sensor that can be used to detect carbon-based chemicals or compounds, such as carbon dioxide. In some implementations, the analyte sensor  174  can also be used to detect whether the user is breathing through their nose or mouth. For example, if the data output by an analyte sensor  174  positioned near the mouth of the user or within the facial mask (in implementations where the user interface  124  is a facial mask) detects the presence of an analyte, the control system  110  can use this data as an indication that the user is breathing through their mouth. 
     The moisture sensor  176  outputs data that can be stored in the memory device  114  and used by the control system  110 . The moisture sensor  176  can be used to detect moisture in various areas surrounding the user (e.g., inside the conduit  126  or the user interface  124 , near the user’s face, near the connection between the conduit  126  and the user interface  124 , near the connection between the conduit  126  and the respiratory therapy device  122 , etc.). Thus, in some implementations, the moisture sensor  176  can be coupled to or integrated into the user interface  124  or in the conduit  126  to monitor the humidity of the pressurized air from the respiratory therapy device  122 . In other implementations, the moisture sensor  176  is placed near any area where moisture levels need to be monitored. The moisture sensor  176  can also be used to monitor the humidity of the ambient environment surrounding the user, for example the air inside the user’s bedroom. The moisture sensor  176  can also be used to track the user’s biometric response to environmental changes. 
     One or more LiDAR sensors  178  can be used for depth sensing. This type of optical sensor (e.g., laser sensor) can be used to detect objects and build three dimensional (3D) maps of the surroundings, such as of a living space. LiDAR can generally utilize a pulsed laser to make time of flight measurements. LiDAR is also referred to as 3D laser scanning. In an example of use of such a sensor, a fixed or mobile device (such as a smartphone) having a LiDAR sensor  178  can measure and map an area extending 5 meters or more away from the sensor. The LiDAR data can be fused with point cloud data estimated by an electromagnetic RADAR sensor, for example. The LiDAR sensor  178  may also use artificial intelligence (AI) to automatically geofence RADAR systems by detecting and classifying features in a space that might cause issues for RADAR systems, such a glass windows (which can be highly reflective to RADAR). LiDAR can also be used to provide an estimate of the height of a person, as well as changes in height when the person sits down, or falls down, for example. LiDAR may be used to form a 3D mesh representation of an environment. In a further use, for solid surfaces through which radio waves pass (e.g., radio-translucent materials), the LiDAR may reflect off such surfaces, thus allowing a classification of different type of obstacles. 
     While shown separately in  FIG.  1   , any combination of the one or more sensors  130  can be integrated in and/or coupled to any one or more of the components of the system  100 , including the respiratory therapy device  122 , the user interface  124 , the conduit  126 , the humidification tank  129 , the control system  110 , the external device  170 , or any combination thereof. For example, the acoustic sensor  141  and/or the RF sensor  147  can be integrated in and/or coupled to the external device  170 . In such implementations, the external device  170  can be considered a secondary device that generates additional or secondary data for use by the system  100  (e.g., the control system  110 ) according to some aspects of the present disclosure. In some implementations, the pressure sensor  132  and/or the flow rate sensor  134  are integrated into and/or coupled to the respiratory therapy device  122 . In some implementations, at least one of the one or more sensors  130  is not coupled to the respiratory therapy device  122 , the control system  110 , or the external device  170 , and is positioned generally adjacent to the user during the sleep session (e.g., positioned on or in contact with a portion of the user, worn by the user, coupled to or positioned on the nightstand, coupled to the mattress, coupled to the ceiling, etc.). More generally, the one or more sensors  130  can be positioned at any suitable location relative to the user such that the one or more sensors  130  can generate physiological data associated with the user and/or the bed partner  220  during one or more sleep session. 
     The data from the one or more sensors  130  can be analyzed to determine one or more sleep-related parameters, which can include a respiration signal, a respiration rate, a respiration pattern, an inspiration amplitude, an expiration amplitude, an inspiration-expiration ratio, an occurrence of one or more events, a number of events per hour, a pattern of events, an average duration of events, a range of event durations, a ratio between the number of different events, a sleep stage, an apnea-hypopnea index (AHI), or any combination thereof. The one or more events can include snoring, apneas, central apneas, obstructive apneas, mixed apneas, hypopneas, an intentional user interface leak, an unintentional user interface leak, a mouth leak, a cough, a restless leg, a sleeping disorder, choking, an increased heart rate, labored breathing, an asthma attack, an epileptic episode, a seizure, increased blood pressure, or any combination thereof. Many of these sleep-related parameters are physiological parameters, although some of the sleep-related parameters can be considered to be non-physiological parameters. Other types of physiological and non-physiological parameters can also be determined, either from the data from the one or more sensors  130 , or from other types of data. 
     The external device  170  includes a display device  172 . The external device  170  can be, for example, a mobile device such as a smart phone, a tablet, a laptop, or the like. Alternatively, the external device  170  can be an external sensing system, a television (e.g., a smart television) or another smart home device (e.g., a smart speaker(s) such as Google Home, Amazon Echo, Alexa etc.). In some implementations, the external device  170  is a wearable device (e.g., a smart watch). The display device  172  is generally used to display image(s) including still images, video images, or both. In some implementations, the display device  172  acts as a human-machine interface (HMI) that includes a graphic user interface (GUI) configured to display the image(s) and an input interface. The display device  172  can be an LED display, an OLED display, an LCD display, or the like. The input interface can be, for example, a touchscreen or touch-sensitive substrate, a mouse, a keyboard, or any sensor system configured to sense inputs made by a human user interacting with the external device  170 . In some implementations, one or more external devices  170  can be used by and/or included in the system  100 . 
     The blood pressure device  180  is generally used to aid in generating physiological data for determining one or more blood pressure measurements associated with a user. The blood pressure device  180  can include at least one of the one or more sensors  130  to measure, for example, a systolic blood pressure component and/or a diastolic blood pressure component. 
     In some implementations, the blood pressure device  180  is a sphygmomanometer including an inflatable cuff that can be worn by a user and a pressure sensor (e.g., the pressure sensor  132  described herein). For example, as shown in the example of  FIG.  2   , the blood pressure device  180  can be worn on an upper arm of the user. In such implementations where the blood pressure device  180  is a sphygmomanometer, the blood pressure device  180  also includes a pump (e.g., a manually operated bulb) for inflating the cuff. In some implementations, the blood pressure device  180  is coupled to the respiratory therapy device  122  of the respiratory therapy system  120 , which in turn delivers pressurized air to inflate the cuff. More generally, the blood pressure device  180  can be communicatively coupled with, and/or physically integrated in (e.g., within a housing), the control system  110 , the memory device  114 , the respiratory therapy system  120 , the external device  170 , and/or the activity tracker  182 . 
     The activity tracker  182  is generally used to aid in generating physiological data for determining an activity measurement associated with the user. The activity measurement can include, for example, a number of steps, a distance traveled, a number of steps climbed, a duration of physical activity, a type of physical activity, an intensity of physical activity, time spent standing, a respiration rate, an average respiration rate, a resting respiration rate, a maximum respiration rate, a respiration rate variability, a heart rate, an average heart rate, a resting heart rate, a maximum heart rate, a heart rate variability, a number of calories burned, blood oxygen saturation, electrodermal activity (also known as skin conductance or galvanic skin response), or any combination thereof. The activity tracker  182  includes one or more of the sensors  130  described herein, such as, for example, the motion sensor  138  (e.g., one or more accelerometers and/or gyroscopes), the PPG sensor  154 , and/or the ECG sensor  156 . 
     In some implementations, the activity tracker  182  is a wearable device that can be worn by the user, such as a smartwatch, a wristband, a ring, or a patch. For example, referring to  FIG.  2   , the activity tracker  182  is worn on a wrist of the user. The activity tracker  182  can also be coupled to or integrated a garment or clothing that is worn by the user. Alternatively, still, the activity tracker  182  can also be coupled to or integrated in (e.g., within the same housing) the external device  170 . More generally, the activity tracker  182  can be communicatively coupled with, or physically integrated in (e.g., within a housing), the control system  110 , the memory device  114 , the respiratory therapy system  120 , the external device  170 , and/or the blood pressure device  180 . 
     While the control system  110  and the memory device  114  are described and shown in  FIG.  1    as being a separate and distinct component of the system  100 , in some implementations, the control system  110  and/or the memory device  114  are integrated in the external device  170  and/or the respiratory therapy device  122 . Alternatively, in some implementations, the control system  110  or a portion thereof (e.g., the processor  112 ) can be located in a cloud (e.g., integrated in a server, integrated in an Internet of Things (IoT) device, connected to the cloud, be subject to edge cloud processing, etc.), located in one or more servers (e.g., remote servers, local servers, etc., or any combination thereof. 
     While system  100  is shown as including all of the components described above, more or fewer components can be included in a system for analyzing data associated with a user’s use of the respiratory therapy system  120 , according to implementations of the present disclosure. For example, a first alternative system includes the control system  110 , the memory device  114 , and at least one of the one or more sensors  130 . As another example, a second alternative system includes the control system  110 , the memory device  114 , at least one of the one or more sensors  130 , and the external device  170 . As yet another example, a third alternative system includes the control system  110 , the memory device  114 , the respiratory therapy system  120 , at least one of the one or more sensors  130 , and the external device  170 . As a further example, a fourth alternative system includes the control system  110 , the memory device  114 , the respiratory therapy system  120 , at least one of the one or more sensors  130 , the external device  170 , and the blood pressure device  180  and/or activity tracker  182 . Thus, various systems for analyzing data associated with a user’s use of the respiratory therapy system  120  can be formed using any portion or portions of the components shown and described herein and/or in combination with one or more other components. 
     As used herein, a sleep session can be defined in a number of ways based at least in part on, for example, an initial start time and an end time. In some implementations, a sleep session is a duration where the user is asleep, that is, the sleep session has a start time and an end time, and during the sleep session, the user does not wake until the end time. That is, any period of the user being awake is not included in a sleep session. From this first definition of sleep session, if the user wakes ups and falls asleep multiple times in the same night, each of the sleep intervals separated by an awake interval is a sleep session. 
     Alternatively, in some implementations, a sleep session has a start time and an end time, and during the sleep session, the user can wake up, without the sleep session ending, so long as a continuous duration that the user is awake is below an awake duration threshold. The awake duration threshold can be defined as a percentage of a sleep session. The awake duration threshold can be, for example, about twenty percent of the sleep session, about fifteen percent of the sleep session duration, about ten percent of the sleep session duration, about five percent of the sleep session duration, about two percent of the sleep session duration, etc., or any other threshold percentage. In some implementations, the awake duration threshold is defined as a fixed amount of time, such as, for example, about one hour, about thirty minutes, about fifteen minutes, about ten minutes, about five minutes, about two minutes, etc., or any other amount of time. 
     In some implementations, a sleep session is defined as the entire time between the time in the evening at which the user first entered the bed, and the time the next morning when user last left the bed. Put another way, a sleep session can be defined as a period of time that begins on a first date (e.g., Monday, Jan. 6, 2020) at a first time (e.g., 10:00 PM), that can be referred to as the current evening, when the user first enters a bed with the intention of going to sleep (e.g., not if the user intends to first watch television or play with a smart phone before going to sleep, etc.), and ends on a second date (e.g., Tuesday, Jan. 7, 2020) at a second time (e.g., 7:00 AM), that can be referred to as the next morning, when the user first exits the bed with the intention of not going back to sleep that next morning. 
     In some implementations, the user can manually define the beginning of a sleep session and/or manually terminate a sleep session. For example, the user can select (e.g., by clicking or tapping) one or more user-selectable element that is displayed on the display device  172  of the external device  170  ( FIG.  1   ) to manually initiate or terminate the sleep session. 
     Referring to  FIG.  3   , an exemplary timeline  240  for a sleep session is illustrated. The timeline  240  includes an enter bed time (t bed ), a go-to-sleep time (t GTS ), an initial sleep time (t sleep ), a first micro-awakening MA 1 , a second micro-awakening MA 2 , an awakening A, a wake-up time (t wake ), and a rising time (t rise ). 
     The enter bed time t bed  is associated with the time that the user initially enters the bed (e.g., bed  230  in  FIG.  2   ) prior to falling asleep (e.g., when the user lies down or sits in the bed). The enter bed time t bed  can be identified based at least in part on a bed threshold duration to distinguish between times when the user enters the bed for sleep and when the user enters the bed for other reasons (e.g., to watch TV). For example, the bed threshold duration can be at least about 10 minutes, at least about 20 minutes, at least about 30 minutes, at least about 45 minutes, at least about 1 hour, at least about 2 hours, etc. While the enter bed time t bed  is described herein in reference to a bed, more generally, the enter time t bed  can refer to the time the user initially enters any location for sleeping (e.g., a couch, a chair, a sleeping bag, etc.). 
     The go-to-sleep time (GTS) is associated with the time that the user initially attempts to fall asleep after entering the bed (t bed ). For example, after entering the bed, the user may engage in one or more activities to wind down prior to trying to sleep (e.g., reading, watching TV, listening to music, using the external device  170 , etc.). The initial sleep time (t sleep ) is the time that the user initially falls asleep. For example, the initial sleep time (t sleep ) can be the time that the user initially enters the first non-REM sleep stage. 
     The wake-up time t wake  is the time associated with the time when the user wakes up without going back to sleep (e.g., as opposed to the user waking up in the middle of the night and going back to sleep). The user may experience one of more unconscious microawakenings (e.g., microawakenings MA 1  and MA 2 ) having a short duration (e.g., 5 seconds, 10 seconds, 30 seconds, 1 minute, etc.) after initially falling asleep. In contrast to the wake-up time t wake , the user goes back to sleep after each of the microawakenings MA 1  and MA 2 . Similarly, the user may have one or more conscious awakenings (e.g., awakening A) after initially falling asleep (e.g., getting up to go to the bathroom, attending to children or pets, sleep walking, etc.). However, the user goes back to sleep after the awakening A. Thus, the wake-up time t wake  can be defined, for example, based at least in part on a wake threshold duration (e.g., the user is awake for at least 15 minutes, at least 20 minutes, at least 30 minutes, at least 1 hour, etc.). 
     Similarly, the rising time t rise  is associated with the time when the user exits the bed and stays out of the bed with the intent to end the sleep session (e.g., as opposed to the user getting up during the night to go to the bathroom, to attend to children or pets, sleep walking, etc.). In other words, the rising time t rise  is the time when the user last leaves the bed without returning to the bed until a next sleep session (e.g., the following evening). Thus, the rising time t rise  can be defined, for example, based at least in part on a rise threshold duration (e.g., the user has left the bed for at least 15 minutes, at least 20 minutes, at least 30 minutes, at least 1 hour, etc.). The enter bed time t bed  time for a second, subsequent sleep session can also be defined based at least in part on a rise threshold duration (e.g., the user has left the bed for at least 4 hours, at least 6 hours, at least 8 hours, at least 12 hours, etc.). 
     As described above, the user may wake up and get out of bed one more times during the night between the initial t bed  and the final t rise . In some implementations, the final wake-up time t wake  and/or the final rising time t rise  that are identified or determined based at least in part on a predetermined threshold duration of time subsequent to an event (e.g., falling asleep or leaving the bed). Such a threshold duration can be customized for the user. For a standard user which goes to bed in the evening, then wakes up and goes out of bed in the morning any period (between the user waking up (t wake ) or raising up (t rise ), and the user either going to bed (t bed ), going to sleep (t GTS ) or falling asleep (t sleep ) of between about 12 and about 18 hours can be used. For users that spend longer periods of time in bed, shorter threshold periods may be used (e.g., between about 8 hours and about 14 hours). The threshold period may be initially selected and/or later adjusted based at least in part on the system monitoring the user’s sleep behavior. 
     The total time in bed (TIB) is the duration of time between the time enter bed time t bed  and the rising time t rise . The total sleep time (TST) is associated with the duration between the initial sleep time and the wake-up time, excluding any conscious or unconscious awakenings and/or micro-awakenings therebetween. Generally, the total sleep time (TST) will be shorter than the total time in bed (TIB) (e.g., one minute short, ten minutes shorter, one hour shorter, etc.). For example, referring to the timeline  240  of  FIG.  3   , the total sleep time (TST) spans between the initial sleep time t sleep  and the wake-up time t wake , but excludes the duration of the first micro-awakening MA 1 , the second micro-awakening MA 2 , and the awakening A. As shown, in this example, the total sleep time (TST) is shorter than the total time in bed (TIB). 
     In some implementations, the total sleep time (TST) can be defined as a persistent total sleep time (PTST). In such implementations, the persistent total sleep time excludes a predetermined initial portion or period of the first non-REM stage (e.g., light sleep stage). For example, the predetermined initial portion can be between about 30 seconds and about 20 minutes, between about 1 minute and about 10 minutes, between about 3 minutes and about 5 minutes, etc. The persistent total sleep time is a measure of sustained sleep, and smooths the sleep-wake hypnogram. For example, when the user is initially falling asleep, the user may be in the first non-REM stage for a very short time (e.g., about 30 seconds), then back into the wakefulness stage for a short period (e.g., one minute), and then goes back to the first non-REM stage. In this example, the persistent total sleep time excludes the first instance (e.g., about 30 seconds) of the first non-REM stage. 
     In some implementations, the sleep session is defined as starting at the enter bed time (t bed ) and ending at the rising time (t rise ), i.e., the sleep session is defined as the total time in bed (TIB). In some implementations, a sleep session is defined as starting at the initial sleep time (t sleep ) and ending at the wake-up time (t wake ). In some implementations, the sleep session is defined as the total sleep time (TST). In some implementations, a sleep session is defined as starting at the go-to-sleep time (t GTS ) and ending at the wake-up time (t wake ). In some implementations, a sleep session is defined as starting at the go-to-sleep time (t GTS ) and ending at the rising time (t rise ). In some implementations, a sleep session is defined as starting at the enter bed time (t bed ) and ending at the wake-up time (t wake ). In some implementations, a sleep session is defined as starting at the initial sleep time (t sleep ) and ending at the rising time (t rise ). 
     Referring to  FIG.  4   , an exemplary hypnogram  250  corresponding to the timeline  240  ( FIG.  3   ), according to some implementations, is illustrated. As shown, the hypnogram  250  includes a sleep-wake signal  251 , a wakefulness stage axis  260 , a REM stage axis  270 , a light sleep stage axis  280 , and a deep sleep stage axis  290 . The intersection between the sleep-wake signal  251  and one of the axes  260 - 290  is indicative of the sleep stage at any given time during the sleep session. 
     The sleep-wake signal  251  can be generated based at least in part on physiological data associated with the user (e.g., generated by one or more of the sensors  130  described herein). The sleep-wake signal can be indicative of one or more sleep stages, including wakefulness, relaxed wakefulness, microawakenings, a REM stage, a first non-REM stage, a second non-REM stage, a third non-REM stage, or any combination thereof. In some implementations, one or more of the first non-REM stage, the second non-REM stage, and the third non-REM stage can be grouped together and categorized as a light sleep stage or a deep sleep stage. For example, the light sleep stage can include the first non-REM stage and the deep sleep stage can include the second non-REM stage and the third non-REM stage. While the hypnogram  250  is shown in  FIG.  4    as including the light sleep stage axis  280  and the deep sleep stage axis  290 , in some implementations, the hypnogram  250  can include an axis for each of the first non-REM stage, the second non-REM stage, and the third non-REM stage. In other implementations, the sleep-wake signal can also be indicative of a respiration signal, a respiration rate, an inspiration amplitude, an expiration amplitude, an inspiration-expiration amplitude ratio, an inspiration-expiration duration ratio, a number of events per hour, a pattern of events, or any combination thereof. Information describing the sleep-wake signal can be stored in the memory device  114 . 
     The hypnogram  250  can be used to determine one or more sleep-related parameters, such as, for example, a sleep onset latency (SOL), wake-after-sleep onset (WASO), a sleep efficiency (SE), a sleep fragmentation index, sleep blocks, or any combination thereof. 
     The sleep onset latency (SOL) is defined as the time between the go-to-sleep time (t GTS ) and the initial sleep time (t sleep ). In other words, the sleep onset latency is indicative of the time that it took the user to actually fall asleep after initially attempting to fall asleep. In some implementations, the sleep onset latency is defined as a persistent sleep onset latency (PSOL). The persistent sleep onset latency differs from the sleep onset latency in that the persistent sleep onset latency is defined as the duration time between the go-to-sleep time and a predetermined amount of sustained sleep. In some implementations, the predetermined amount of sustained sleep can include, for example, at least 10 minutes of sleep within the second non-REM stage, the third non-REM stage, and/or the REM stage with no more than 2 minutes of wakefulness, the first non-REM stage, and/or movement therebetween. In other words, the persistent sleep onset latency requires up to, for example, 8 minutes of sustained sleep within the second non-REM stage, the third non-REM stage, and/or the REM stage. In other implementations, the predetermined amount of sustained sleep can include at least 10 minutes of sleep within the first non-REM stage, the second non-REM stage, the third non-REM stage, and/or the REM stage subsequent to the initial sleep time. In such implementations, the predetermined amount of sustained sleep can exclude any micro-awakenings (e.g., a ten second micro-awakening does not restart the 10-minute period). 
     The wake-after-sleep onset (WASO) is associated with the total duration of time that the user is awake between the initial sleep time and the wake-up time. Thus, the wake-after-sleep onset includes short and micro-awakenings during the sleep session (e.g., the micro-awakenings MA 1  and MA 2  shown in  FIG.  4   ), whether conscious or unconscious. In some implementations, the wake-after-sleep onset (WASO) is defined as a persistent wake-after-sleep onset (PWASO) that only includes the total durations of awakenings having a predetermined length (e.g., greater than 10 seconds, greater than 30 seconds, greater than 60 seconds, greater than about 5 minutes, greater than about 10 minutes, etc.) 
     The sleep efficiency (SE) is determined as a ratio of the total time in bed (TIB) and the total sleep time (TST). For example, if the total time in bed is 8 hours and the total sleep time is 7.5 hours, the sleep efficiency for that sleep session is 93.75%. The sleep efficiency is indicative of the sleep hygiene of the user. For example, if the user enters the bed and spends time engaged in other activities (e.g., watching TV) before sleep, the sleep efficiency will be reduced (e.g., the user is penalized). In some implementations, the sleep efficiency (SE) can be calculated based at least in part on the total time in bed (TIB) and the total time that the user is attempting to sleep. In such implementations, the total time that the user is attempting to sleep is defined as the duration between the go-to-sleep (GTS) time and the rising time described herein. For example, if the total sleep time is 8 hours (e.g., between 11 PM and 7 AM), the go-to-sleep time is 10:45 PM, and the rising time is 7:15 AM, in such implementations, the sleep efficiency parameter is calculated as about 94%. 
     The fragmentation index is determined based at least in part on the number of awakenings during the sleep session. For example, if the user had two micro-awakenings (e.g., micro-awakening MA 1  and micro-awakening MA 2  shown in  FIG.  4   ), the fragmentation index can be expressed as 2. In some implementations, the fragmentation index is scaled between a predetermined range of integers (e.g., between 0 and 10). 
     The sleep blocks are associated with a transition between any stage of sleep (e.g., the first non-REM stage, the second non-REM stage, the third non-REM stage, and/or the REM) and the wakefulness stage. The sleep blocks can be calculated at a resolution of, for example, 30 seconds. 
     In some implementations, the systems and methods described herein can include generating or analyzing a hypnogram including a sleep-wake signal to determine or identify the enter bed time (t bed ), the go-to-sleep time (t GTS ), the initial sleep time (t sleep ), one or more first micro-awakenings (e.g., MA 1  and MA 2 ), the wake-up time (t wake ), the rising time (t rise ), or any combination thereof based at least in part on the sleep-wake signal of a hypnogram. 
     In other implementations, one or more of the sensors  130  can be used to determine or identify the enter bed time (t bed ), the go-to-sleep time (t GTS ), the initial sleep time (t sleep ), one or more first micro-awakenings (e.g., MA 1  and MA 2 ), the wake-up time (t wake ), the rising time (t rise ), or any combination thereof, which in turn define the sleep session. For example, the enter bed time t bed  can be determined based at least in part on, for example, data generated by the motion sensor  138 , the microphone  140 , the camera  150 , or any combination thereof. The go-to-sleep time can be determined based at least in part on, for example, data from the motion sensor  138  (e.g., data indicative of no movement by the user), data from the camera  150  (e.g., data indicative of no movement by the user and/or that the user has turned off the lights), data from the microphone  140  (e.g., data indicative of the using turning off a TV), data from the external device  170  (e.g., data indicative of the user no longer using the external device  170 ), data from the pressure sensor  132  and/or the flow rate sensor  134  (e.g., data indicative of the user turning on the respiratory therapy device  122 , data indicative of the user donning the user interface  124 , etc.), or any combination thereof. 
     A user interface  300  is illustrated in  FIGS.  5 A and  5 B . User interface  300  may be the same as or similar to user interface  124  as discussed herein with respect to  FIGS.  1  and  2   , and can be used in conjunction with any of the above-described components or features of system  100 , including respiratory therapy system  120  and respiratory therapy device  122 . The user interface  300  includes a strap assembly  310 , a cushion  330 , a frame  350 , and a connector  370 . The strap assembly  310  is configured to be positioned generally about at least a portion of the user’s head when the user wears the user interface  300 . The strap assembly  310  can be coupled to the frame  350  and positioned on the user’s head such that the user’s head is positioned between the strap assembly  310  and the frame  350 . 
     In some implementations, the cushion  330  is positioned between the user’s face and the frame  350  to form a seal on the user’s face. A first end portion  372 A of the connector  370  is coupled to the frame  350 , while a second end portion  372 B of the connector  370  can be coupled to a conduit (such as conduit  126 ). In turn, the conduit can be coupled to the air outlet of a respiratory therapy device (such as respiratory therapy device  122 ). A blower motor in the respiratory therapy device is operable to generate a flow of pressurized air out of the air outlet, to thereby provide pressurized air to the user. The pressurized air can flow from the respiratory therapy device and through the conduit, the connector  370 , the frame  350 , and the cushion  330 , until the air reaches the user’s airway through the user’s mouth, nose, or both. 
     The strap assembly  310  is formed from a rear portion  312 , a pair of upper straps  314 A and  314 B, and a pair of lower straps  316 A and  316 B. The rear portion  312  of the strap assembly is generally positioned behind the user’s head when the user wears the user interface  300 . The upper straps  314 A,  314 B and the lower straps  316 A,  316 B extend from the rear portion  312  toward the front of the user’s face. In the illustrated implementation, the rear portion  312  has a circular shape. However, the rear portion  312  may also have other shapes. The rear portion  312 , the upper straps  314 A,  314 B, and the lower straps  316 A,  316 B can be formed or woven from a generally stretchy or resilient material, such as fabric, elastic, rubber, etc., or any combination of materials. In some implementations, the electrical wires or traces may extend through the interior of a portion of the strap assembly  310 . This portion of the strap assembly  310  may generally form around the electrical wires or traces, or may have a hollow interior or channel through which electrical wires or traces extend, as discussed in further detail below. 
     The upper straps  314 A,  314 B and the lower straps  316 A,  316 B each have first ends originating at the rear portion  312 , and second ends that couple to the frame  350 . When the user wears the user interface  300 , the tension provided by the strap assembly  310  holds the frame  350  to the user’s face, thus securing the user interface  300  to the user’s head. 
     In some implementations, a tension sensor can be embedded in one of the straps of the strap assembly. For example,  FIG.  5 B  illustrates a tension sensor  313  embedded in upper strap  314 A. The tension sensor  313  is configured to measure tension in the straps of the user interface  124 . As discussed, the user interface  124  is generally fasted to the user  210 ’s head using straps that can be tightened using Velcro™ or some other fastener. The tension sensor  313  can sense the tension in the straps, which can then be used to inform and/or instruct the user  210  about the correct fitting of the user interface  124 . The tension sensor  313  can be integrated into yarn, fiber, wire, carbon fiber, warps, webs. etc. As the tension in the strap increases or decreases, the sensor element of the tension sensor  313  is deflected, causing a change in the voltage of an output signal. The tension sensor  313  can have high elasticity and low resistance, and the ability to be washed. In some implementations, the tension sensor  313  measures the diameter of an inflatable body by the principles of respiratory inductance plethysmography. The tensor sensor  313  can also be an electric impedance plethysmography sensor, a magnetometer, a strain gauge sensor, or be made of piezo-resistive material displacement sensor. 
     The frame  350  is generally formed from a body  352  that defines a first surface  354 A and an opposing second surface  354 B. When the user wears the user interface  300 , the first surface  354 A faces away from the user’s face, while the second surface  354 B faces toward the user’s face. The frame also defines an annular aperture  356  into which the cushion  330  and the connector  370  can be inserted, to thereby physically couple the cushion  330  and the connector  370  to the frame  350 . 
     The cushion  330  can be coupled to the inside of the frame  350  adjacent to the second surface  354 B, such that the cushion  330  is positioned between the user’s face and the frame  350 . The cushion  330  can be made from the same as or similar to the cushion of user interface  124 , and thus can be formed of a conformal material that forms an air-tight seal with the user’s face. The cushion  330  defines an aperture  336 , and includes an annular projection  338  extending from the cushion  330  about the aperture  336  of the cushion. The annular projection  338  is inserted into the annular aperture  356  of the frame  350 , such that the annular aperture  336  of the cushion  330  overlaps with the annular aperture  356  of the frame  350 . In some implementations, the annular projection  338  of the cushion  330  is releasably secured to the body  352  of the frame  350  via a friction fit between the annular projection  338  and the body  352  around the annular aperture  356 . 
     In other implementations, the annular projection  338  and the frame  350  can have mating features that mate with each other to secure the cushion  330  to the frame  350 . For example, the annular projection  338  of the cushion  330  may include an outwardly-extending peripheral flange, and the body  352  of the frame  350  can include a corresponding inwardly-extending peripheral flange about the annular aperture  356 . When the annular projection  338  of the cushion  330  is inserted into the annular aperture  356  of the frame  350 , the peripheral flanges can slide or snap past each other, to thereby secure the cushion  330  to the frame  350 . In additional implementations, the cushion  330  is held in place by the tension provided by the strap assembly  310 , and is not physically coupled to the frame  350 . In still other implementations, the cushion  330  and the frame  350  can be formed as a single integral piece. 
     The connector  370  can be coupled to the opposite side of the frame  350  in a similar manner to the cushion  330 . The first end portion  372 A of the connector  370  has a generally cylindrical shape and can be inserted into the annular aperture  356  of the frame  350 , such that a hollow interior  376  of the end portion  372 A (see  FIG.  6 A ) overlaps with the annular aperture  356 , and the aperture  336  of the cushion  330 . The opposing second end portion  372 B of the connector  370  is then coupled to the conduit, such that the user’s face (including the user’s mouth and/or nose) is in fluid communication with the conduit through the cushion  330 , the frame  350 , and the connector  370 . 
     The first end portion  372 A of the connector  370  is generally annular-shaped, and fits into the annular aperture  356  of the frame  350 . The frame  350  also includes an annular projection  358  that extends from the second surface  354 B of the frame  350  and is formed about the annular aperture  356 . When the first end portion  372 A is inserted into the annular aperture  356  of the frame  350 , an inner surface of the annular projection  358  overlaps with an outer surface of the first end portion  372 AA of the connector  370 . 
     In some implementations, a friction fit between the annular projection  358  and the first end portion  372 A secures the connector  370  to the frame  350 . In other implementations, the connector  370  can include a fastener configured to secure the connector  370  to the frame  350 . In one example, the annular projection  358  has an outwardly-extending peripheral flange, and the fastener is one or more deflectable latches formed on the first end portion  372 A of the connector  370 . As the first end portion  372 A slides is inserted within the annular projection  358 , the deflectable latch slides over the peripheral flange such that the deflectable latch is positioned outside of the annular projection  358 . As the deflectable latch passes by the peripheral flange, the peripheral flange pushes the deflectable latch away from the annular projection  358 . The deflectable latch then returns to its original position, such that the connector  370  cannot be removed from the frame  350  without manually deflecting the deflectable latch away from the annular projection  358 . 
     The frame  350  includes a T-shaped extension strip  360  extending upward from an upper end  351 A of the body  352 . In some implementations, the extension strip  360  is integrally formed with the body  352 . In other implementations, the extension strip  360  is a separate component that is coupled to the body  352 . When the user wears the user interface  300 , the extension strip  360  generally extends up to the user’s forehead. In some implementations, the extension strip  360  includes a cooling portion or mechanism that contacts and cools the user  210 ’s forehead, which can help users with insomnia fall asleep. 
     The lower straps  316 A,  316 B extend toward the frame  350  from the rear portion  312  of the strap assembly  310 , and are coupled to opposite sides of a lower end  351 B of the body  352 . The upper straps  314 A,  314 B extend toward the frame  350  from the rear portion  312  of the strap assembly  310 , and are coupled to opposite sides of the upper end  361  extension strip  360  (e.g., the generally horizontal “cross” of the T). The frame  350  can include a variety of different strap attachment points to couple with the upper straps  314 A,  314 B and the lower straps  316 A,  316 B. 
     One type of strap attachment point is shown in the extension strip  360 . The upper end  361  of the extension strip  360  includes two apertures  362 A,  362 B. These apertures can be integrally formed in the extension strip  360  itself, or may be formed as part of a separate component or piece that is coupled to the extension strip  360 . The apertures  362 A,  362 B are shaped to allow the ends  315 A,  315 B of the upper straps  314 A,  314 B to be inserted through the apertures  362 A,  362 B. The ends  315 A,  315 B can then loop back and fasten to remainder of the upper straps  314 A,  314 B via any suitable mechanism, such as Velcro™, adhesive, etc. The upper straps  314 A,  314 B are thus secured to the extension strip  360  of the frame  350 . 
     The frame  350  is shown with a different type of strap attachment point used to couple the lower straps  316 A,  316 B to the frame  350 . The frame  350  includes two lateral strips  364 A,  364 B extending away from opposite ends of the lower end  351 B of the body  352 . The first end of each lateral strip  364 A,  364 B is coupled to the body  352 , and a corresponding magnet  366 A,  366 B is disposed at the second end of each lateral strip  364 A,  364 B. A magnet  318 A is coupled to end  317 A of lower strap  316 A, while a magnet  318 B is coupled to end  317 B of lower strap  316 B. Magnet  318 A can be secured to magnet  366 A via magnetic attraction, while magnet  318 B can be secured to magnet  366 B via magnetic attraction, to thereby couple the lower straps  316 A,  316 B to the body  352  of the frame  350 . 
     In some implementations, the frame  350  does not include the extension strip  360 , and the upper straps  314 A,  314 B are instead coupled to the frame, above the lateral strips  364 A,  364 B. The upper straps  314 A,  314 B in these implementations extend past the user  210 ’s temples and around to the rear of the user  210 ’s head. The frame  350  may include upper lateral strips which the upper straps  314 A,  314 B are coupled to. 
     The user interface  300  can also include one or more sensors  390 . While  FIG.  5 B  generally only shows a single sensor, any number of sensors can be coupled to the strap assembly  310 . In some implementation, the one or more sensors  390  are coupled to the strap assembly  310 , and are configured to abut a target area of the user when the user wears the user interface  300 . The target area could be the user’s forehead, temple, throat, neck, ear, etc. Generally, the one or more sensors  390  abutting the target area can include sensors that directly contact the target area of the user (e.g., the sensors touch the target area of the user), and/or sensors that do not directly contact the user (e.g., the sensors are separated from the target area of the user in some fashion). 
     In some implementations, the one or more sensors  390  are contact sensors, which can include an electroencephalography (EEG) sensor, an electrocardiogram (ECG) sensor, an electromyography (EMG) sensor, an electrooculography (EOG) sensor, an acoustic sensor, a peripheral oxygen saturation (SpO 2 ) sensor, a galvanic skin response (GSR) sensor, or any combination thereof. The contact sensors can directly contact the target area of the user, or may contact a layer of material positioned between the contact sensors and the target area, such as fabric (which could be the strap assembly  310 ), silicone (which could be the cushion  330 ), foam (which could be the cushion  330 ), plastic (which could be the frame  350 ), etc. In some implementations, the one or more sensors  390  are non-contact sensors, which can include a carbon dioxide (CO 2 ) sensor (to measure CO 2  concentration), an oxygen (O 2 ) sensor (to measure O 2  concentration), a pressure sensor, a temperature sensor, a motion sensor, a microphone, an acoustic sensor, a flow sensor, a tension sensor, or any combination thereof. Generally, these non-contact sensors can be spaced apart from the target area, such that there is air (or any other material) positioned between the one or more sensors  390  and the target area. 
     In other implementations, the one or more sensors  390  are not coupled to the strap assembly  310 , but are instead located at other positions within the user interface  300 , such as within the connector  370 . The one or more sensors  390  can be any one or more of the sensors  130  described herein with respect to  FIG.  1   , and can additionally or alternatively include other types of sensors as well. In some implementations, the one or more sensors  390  can include one or more non-contact sensors and one or more contact sensors. In some of these implementations, the non-contact sensor is not coupled to the strap assembly  310 , but is instead disposed in the cushion  330 , the frame  350 , or the connector  370 . Moreover, the user interface  300  can include multiple non-contact sensors disposed in any combination of these locations. In one example, one of the one or more sensors  390  is coupled to the frame  350 , and contacts the target area via the cushion  330 . In this example, the sensor could be positioned at or near the surface of the cushion  330 . Thus, the one or more sensors  390  can include any combination of sensors that (i) directly touch the target area or (ii) are spaced apart from the target area and are separated from the target area by air or some other material. The one or more sensors  390  can include any combination of contact sensors and non-contact sensors. 
     Generally, the one or more sensors  390  of the user interface  300  need to be electrically connected to a control system and a memory device (such as control system  110  and memory device  114  of system  100 ) in order to transmit data to the control system and memory device. These data can be used to modify the operation of the respiratory therapy device, and can also be used for other purposes. In order send the data from the one or more sensors  390  to the control system and memory device, the one or more sensors  390  can be electrically connected to various parts of the user interface  300 , including the frame  350  and the connector  370 . Data from the one or more sensors  390  can be transmitted using the electrical connection between the one or more sensors  390 , the frame  350 , and the connector  370 . Thus, wherever the one or more sensors  390  are located in the user interface  300 , the one or more sensors  390  need to be able to be electrically connected to the control system and the memory device. 
       FIGS.  6 A and  6 B  show the electrical connection between the frame  350  and the connector  370 . The frame  350  includes electrical contacts  368 A,  368 B,  368 C, and  368 D disposed on the inside of the annular projection  358 . The electrical contacts  368 A- 368 D can be formed on the inner surface of the annular projection  358 , or may extend radially inward from the inner surface of the annular projection  358 . In  FIGS.  6 A and  6 B , a portion of the annular projection  358  has been removed to better show the electrical contacts  368 A- 368 D. The connector  370  includes corresponding electrical contacts  378 A,  378 B,  378 C,  378 D disposed on the surface of the annular-shaped end portion  372 A. 
     When the end portion  372 A of the connector  370  is inserted into the annular aperture  356  of the frame  350 , each electrical contact of the frame  350  physically contacts one of the electrical contacts of the connector  370 , such that the frame  350  is electrically connected to the connector  370 . Thus, electrical contact  368 A is physically and electrically connected to electrical contact  378 A, electrical contact  368 B is physically and electrically connected to electrical contact  378 B, electrical contact  368 C is physically and electrically connected to electrical contact  378 C, and electrical contact  368 D is physically and electrically connected to electrical contact  378 D. Thus, the connector  370  can be physically and electrically connected to the frame  350 . 
     In the illustrated implementation, each electrical contact  378 A- 378 D of the connector  370  is an annular electrical contact that forms a ring on the surface of the end portion  372 A of the connector  370 . Annular electrical contacts  378 A- 378 D may be formed on the surface of end portion  372 A, or may extend radially outward from the surface of end portion  372 A. The electrical contacts  368 A- 368 D of the frame  350  are formed as single electrical pads, each located at one location on the inner surface of the annular projection  358 . The electrical contacts  368 A- 368 D may be formed on the inner surface of the annular projection  358 , or may be formed as pins that extend radially inward from the inner surface of the annular projection  358 . The annular shapes of electrical connectors  378 A- 378 D ensures that if the connector  370  is rotated relative to the frame  350  once the end portion  372 A is inserted into the annular aperture  356  of the frame  350 , some portion of each electrical contact  378 A- 378 D will always be physically touching its corresponding electrical contact  368 A- 368 D of the frame  350 . 
     In other implementations however, the electrical contacts  368 A- 368 D of the frame  350  may have annular shapes that form rings on the inner surface of the annular projection  358 , while the electrical contacts  378 A- 378 D of the connector  370  are single electrical pads, each located at one location on the outer surface of end portion  372 A. In still other implementations, electrical contacts  368 A- 368 D and electrical contacts  378 A- 378 D are all annular electrical contacts. In further implementations, electrical contacts  368 A- 368 D and electrical contacts  378 A- 378 D are all formed as single electrical pads. In some implementations, electrical contacts  368 A- 368 D and electrical contacts  378 A- 378 D are at least partially annular, meaning that they can form partial rings. The rings can be quarter-rings (e.g., 90°), half-rings (e.g., 180°), three-quarter rings (e.g., 270°), or any other partially annular arrangement. 
     The connector  370  includes electrical contacts  382 A- 382 D located at the other end portion  372 B. Electrical contact  382 A is electrically connected to electrical contact  378 A via an electrical pathway  380 A formed in the hollow interior  376  of the connector. Electrical contact  382 B is electrically connected to electrical contact  378 B via an electrical pathway  380 B formed in the hollow interior  376  of the connector. Electrical contact  382 C is electrically connected to electrical contact  378 C via an electrical pathway  380 C formed in the hollow interior  376  of the connector. Electrical contact  382 D is electrically connected to electrical contact  378 D via an electrical pathway  380 D formed in the hollow interior  376  of the connector. 
     The electrical pathways  380 A- 380 D can be formed in a variety of manners. In some implementations, electrical pathways  380 A- 380 D are electrical traces formed on the inner surface of the hollow interior  376  of the connector  370 , or within the connector  370  itself. In other implementations, electrical pathways  380 A- 380 D are formed from wires positioned inside the hollow interior  376  of the connector  370 . The second end portion  372 A of the connector  370  can be inserted into the conduit, which can have similar electrical contacts. In turn, the electrical contacts of the conduit may be electrically connected to the control system and memory device when the conduit is coupled to the respiratory therapy device. Thus, the connector  370  can be physically and electrically coupled to a conduit. 
     The electrical contacts  368 A- 368 D of the annular projection  358  can be electrically connected to the strap attachment points of the frame  350 . Electrical pathways  369 A and  369 B extend from electrical contacts  368 A and  368 B, respectively, through lateral strip  364 A, and out to magnet  366 A. As discussed further herein, lateral strip  364 A and magnet  366 A can be electrically connected to one of the straps of the strap assembly  310 . In a similar manner, electrical pathways  369 C and  369 D extend from electrical contacts  368 C and  368 D, respectively, upwards through the extension strip  360 . While not shown in  FIGS.  6 A and  6 B , one or more electrical pathways may also extend through lateral strip  364 B out to magnet  366 B. 
     Electrical pathways  369 A- 369 D can be formed in a variety of different manners. In some implementations, electrical pathways  369 A- 369 D are formed by wires positioned between adj acent to the second surface of the body  352 , between the frame  350  and the cushion  330 . In other implementations, electrical pathways  369 A- 369 D can be formed by electrical traces that are formed on the second surface of the body  352 , or formed within the body  352  between the first surface and the second surface. 
     Electrical pathways  3689 - 369 D shown in  FIGS.  6 A and  6 B  are example implementations. In other implementations, any number of electrical pathways can be formed between the electrical contacts  368 A- 368 D of the annular projection  358  and any point on the frame  350 . For example, some of the electrical contacts  368 A- 368 D can be electrically connected to lateral strip  364 B and magnet  366 B, instead of or in addition to electrical connections to lateral strip  364 A and magnet  366 A, and extension strip  360 . 
       FIG.  6 C  shows a cross-sectional view of the annular projection  358  of the frame  350  and the first end portion  372 A of the connector  370 , prior to the first end portion  372 A being inserted into the annular aperture  356  of the frame  350 .  FIG.  6 D  shows a cross-section view after the first end portion  372 A is inserted into the annular aperture  356  of the frame  350 . Electrical contacts  368 A- 368 D of the annular projection  358  are formed as single pads on the inner surface of the annular projection  358 . Electrical contacts  378 A- 378 D of the connector  370  are annular electrical contacts formed as rings on the outer surface of the first end portion  372 . Electrical pathways  369 A- 369 D of the frame  350  are electrically connected to electrical contacts  368 A- 368 D, respective. Electrical pathways  380 A- 380 D of the connector  370  are electrically connected to electrical contacts  378 A- 378 D, respective. 
     Once the first end portion  372 A is inserted into the annular aperture  356  of the frame  350 , annular electrical contacts  378 A- 378 D come into contact with electrical contacts  368 A- 368 D, thereby electrically connecting the two sets of electrical contacts. In turn, electrical pathways  369 A- 369 D are electrically connected to electrical pathways  378 A- 378 D. Because electrical contacts  378 A- 378 D are annular-shaped, the connector  370  can be rotated through any number of revolutions, and the connector  370  will remain electrically connected to the frame  350 . 
       FIGS.  7 A and  7 B  illustrate an implementation for electrically connecting the strap attachment points of the frame  350  to straps of the strap assembly  310 .  FIG.  7 A  shows only the strap attachment point formed by lateral strip  364 A. However, this implementation can be used for lateral strip  364 B, or for other strap attachment points of the frame  350 . 
     As shown in  FIG.  7 A , electrical pathways  369 A and  369 B extend through lateral strip  364 A and terminate at magnets  365 A and  365 B. Magnets  365 A and  365 B are generally the same as or similar to magnet  366 A in  FIGS.  6 A and  6 B , except that the magnet is formed from two smaller magnets  365 A and  365 B. Electrical pathway  369 A terminates at an electrical contact  371 A that is adjacent to magnet  365 A. Similarly, electrical pathway  369 B terminates at an electrical contact  371 B that is adjacent to magnet  365 B. In the illustrated implementation, electrical contact  371 A is generally flush with the surface of magnet  365 A, while electrical contact  371 B is generally flush with the surface of magnet  365 B. 
     The end  317 A of lower strap  316 A is generally formed in the same fashion. Magnets  319 A and  319 B are mounted at the end  317 A of the lower strap  316 A. Magnets  319 A and  319 B are generally the same as magnet  318 A shown in  FIG.  5 B , except that the magnet is formed from two smaller magnets  319 A and  319 B. Magnet  319 A includes electrical contact  320 A that is generally flush with the surface of magnet  319 A. Similarly, magnet  319 B includes electrical contact  320 B that is generally flush with the surface of magnet  319 B. Electrical contact  320 A is electrically connected to electrical pathway  322 A, while electrical contact  320 B is electrically connected to electrical pathway  322 B. Electrical pathways  322 A,  322 B extend through the lower strap  316 A, to any desired point along the strap assembly  310 . Generally, electrical pathways  322 A and  322 B extend to a point along the strap assembly  310  that is in close proximity to the target area on the user’s face. Thus, the electrical pathways  322 A and  322 B generally have a first end positioned at the electrical contacts  320 A,  320 B, respectively, and a second end position at some other portion of the strap assembly  310  near the target area of the user. 
     When the end  317 A of lower strap  316 A is brought near lateral strip  364 A, magnets  319 A and  319 B are magnetically attracted to magnets  365 A and  365 B. The magnetic attraction secures end  317 A of lower strap  316 A to lateral strip  364 A, which causes electrical contact  371 A to physically contact electrical contact  320 A and electrical contact  371 B to physically contact electrical contact  320 B. Electrical pathway  369 A is thus electrically connected to electrical pathway  322 A, while electrical pathway  369 B is electrically connected to electrical pathway  322 B. Because of the electrical connection between lateral strip  364 A, the annular projection  358  of the frame  350 , and the connector  370 , electrical pathways  322 A,  322 B (which extend into the strap assembly  310 ) are electrically connected to the connector  370 . Thus, the frame  350  can be physically and electrically connected to the strap assembly  310 . 
     The end  317 A of lower strap  316 A includes a rotation-locking feature, and the lateral strip  364 A includes a corresponding rotation-locking feature. In the illustrated implementation, rotation-locking feature of end  317 A of the lower strap  316 A is a T-shaped projection  324  that extends away from magnets  319 A and  319 B, and the rotation-locking feature of the lateral strip  364 A is a channel  373  defined between magnets  365 A and  365 B sized to receive at least a portion of the T-shaped projection  324 . Generally, the linear portion of the T-shaped projection  324  can fit into the channel  373  when the end  317 A of lower strap  316 A is secured to lateral strip  364 A. The T-shaped projection  324  is thus locked between the magnets  365 A and  365 B, preventing magnets  365 A and  365 B from rotating relative to magnets  319 A and  319 B. This locked rotation turn ensures that electrical contact  371 A remains physically touching electrical contact  320 A, and that electrical contact  371 B remains physically touching electrical contact  320 B. Additionally, the lower curved portion of the T-shaped projection  324  generally fit underneath magnets  365 A and  365 B (relative to the plane of  FIG.  7 A ), which prevents the lower strap  316 A from inadvertently being pulled away from lateral strip  364 A. 
     The electrical pathways  322 A and  322 B that extend from end  317 A of lower strap  316 A into the strap assembly  310  can be formed in a variety of different manners. In some implementations, the electrical pathways  322 A and  322 B are formed from wires that run through a generally hollow interior of the lower strap  316 A and/or any other portion of the strap assembly  310 . In other implementations, the strap assembly  310  is not hollow, and the wires forming the electrical pathways  322 A and  322 B are instead woven in with the material forming the strap assembly  310 . In still other implementations, electrical pathways  322 A and  322 B are formed by electrical traces that run along the surface of the lower strap  316 A and the rest of the strap assembly  310 . 
     By utilizing the electrical pathways and electrical contacts of the user interface  300 , the one or more sensors  390  can be placed at any suitable location, and can be electrically connected to the connector  370 . By coupling the connector  370  with a conduit having its own electrical pathways (e.g., wires or traces inside the conduit), the one or more sensors  390  can be electrically coupled to a control system and memory device disposed in or near the respiratory therapy device. 
     In some implementations, the one or more sensors  390  are positioned near the connector  370 . In this implementation, the one or more sensors  390  are electrically connected to one or more of the electrical contacts  378 A- 378 D of the connector  370 , so that data generated by the one or more sensors  390  can be transmitted via electrical contacts  378 A- 378 D. In these implementations, the one or more sensors  390  may be positioned inside the connector  370 . 
     In other implementations, the one or more sensors  390  are positioned near the frame  350 . For example, the one or more sensors  390  can be positioned between the user’s face and the cushion  330 , between the cushion  330  and the frame  350 , or inside the annular aperture  356  of the frame  350 . In this implementation, the one or more sensors  390  are electrically connected to one or more of the electrical contacts  368 A- 368 D of the frame  350 , so that data generated by the one or more sensors  390  can be transmitted via electrical contacts  368 A- 368 D of the frame  350 , and electrical contacts  378 A- 378 D of the connector  370 . 
     In further implementations, the one or more sensors  390  are positioned near either of the strap attachments points of the frame  350 . In some of these implementations, the one or more sensors  390  are positioned in or near the extension strip  360 , and is electrically connected through the extension strip  360  to the frame  350  and the connector  370 . In others of these implementations, the one or more sensors  390  can be positioned, for example, near the magnet  366 A of the lateral strip  364 A, and electrically connected to one or both of electrical contacts  371 A and  371 B, so that data generated by the one or more sensors  390  can be transmitted through electrical contacts  371 A and  371 B of the lateral strip  364 A, electrical contacts  368 A- 368 D of the frame  350 , and electrical contacts  378 A- 378 D of the connector  370 . 
     In still other implementations, the one or more sensors  390  are positioned near the end of one of the lower straps, such as near end  317 A of lower strap  316 A. The one or more sensors  390  can be electrically connected to one or both of electrical contacts  320 A and  320 B, so that data generated by the one or more sensors  390  can be transmitted through electrical contacts  320 A and  320 B, electrical contacts  371 A and  371 B of the lateral strip  364 A, electrical contacts  368 A- 368 D of the frame  350 , and electrical contacts  378 A- 378 D of the connector  370 . 
     In some implementations, the one or more sensors  390  are positioned along the strap assembly  310  adjacent to the target area of the user. In these implementations, the one or more sensors  390  can be electrically connected to the electrical pathway extending through the strap assembly  310 , such as electrical pathways  322 A and  322 B. Thus, data generated by the one or more sensors  390  can be transmitted through electrical pathways  322 A and  322 B, electrical contacts  320 A and  320 B, electrical contacts  371 A and  371 B of the lateral strip  364 A, electrical contacts  368 A- 368 D of the frame  350 , and electrical contacts  378 A- 378 D of the connector  370 . Further, the one or more sensors  390  can include contact portions that contact the target area of the user, and a wire that electrically connects the contact portion of the sensor with the electrical pathways in the strap assembly  310 , such as electrical pathways  322 A and  322 B. 
     In even further implementations, instead of being electrically connected to the control system and memory device through a conduit, the one or more sensors  390  can be electrically connected to a processing device (such as a microprocessor) that is located in the connector  370 . In these implementations, the microprocessor is electrically connected to the electrical contacts  378 A- 378 D of the connector  370 , so that data generated by the sensor can be transmitted via the strap assembly  310 , the frame  350 , and the connector  370  to the microprocessor. 
     The user interface  124  and/or the conduit  126  may also include one or more safety features to mitigate the risk of electrical shock due to excessive leakage currents, which may result from worn or defective circuity, or inadvertently exposed components. In some implementations, opto-isolators or 1:1 transformers can be used to electrically isolate various components. In addition, heating of any of the electrical components can be mitigated, for example using a variety of different insulators. 
       FIG.  8    illustrates a user (such as user  210 ) wearing the user interface  300  with three different sensors coupled to the strap assembly  310  and being positioned adjacent to or abutting different portions of the user. As shown, the strap assembly  310  is positioned around the user’s head, and is coupled to the frame  350 . The cushion  330  is attached to the frame  350  and positioned between the user’s face and the frame  350 . The connector  370  is coupled to the frame  350 . 
     The user interface  300  in  FIG.  8    includes three sensors  402 A,  402 AB, and  402 C located at or adjacent to different areas of the strap assembly  310 , and abutting different areas on the user. Sensor  402 A is located adjacent to the lower strap  316 A, sensor  402 B is located in the extension strip  360 , and sensor  402 C is located in the upper strap  314 A. 
     In the illustrated implementation, sensor  402 A is clipped to the user’s ear, and can be an SpO 2  sensor used to measure peripheral oxygen saturation. By clipping the SpO 2  sensor to the user’s ear instead of another portion of the user (such as a finger or a toe), more reliable measurements of peripheral oxygen saturation can be obtained. Sensor  402 A is electrically connected to the connector  370  through the frame  350 , a first electrical pathway  404 A, a second electrical pathway  404 B, and a third electrical pathway  404 C. The first electrical pathway  404 A is disposed in the frame  350 , and can be a wire or an electrical trace. The first electrical pathway  404 A out to a strap attachment point of the frame  350 , where the lower strap  316 A is coupled to the frame  350 . The second electrical pathway  404 B extends through the lower strap  316 A itself, and can be a wire or an electrical trace positioned inside the lower strap  316 A or on the surface of lower strap  316 A. The first electrical pathway  404 A and the second electrical pathway  404 B can be electrically coupled using magnets located in the frame  350  and the lower strap  316 A, as illustrated in  FIG.  7   . The third electrical pathway  404 A extends out of the lower strap  316 A to the sensor  402 A clipped to the user’s ear. The third electrical pathway  404 A is thus generally formed as a wire. Thus, data generated by the sensor  402 A can be transmitted via the lower strap  316 A, the frame  350 , and the connector  370 . 
     In other implementations, sensor  402 A could be located adjacent to the neck or throat of the user. In these implementations, the second electrical pathway  404 B can extend out of the lower strap  316 A and downward to the sensor  402 A. 
     In the illustrated implementation, sensor  402 B is a contact sensor that abuts the user’s forehead (such as an EEG sensor) when the user interface  300  is worn by the user. The sensor  402 B can measure brain activity at of the frontal lobe, which can aid in determining which stage of sleep the user, and in detecting arousals and micro-arousals during the user’s sleep session. The sensor  402 B is electrically connected to the connector  370  through the frame  350  and through electrical pathway  406 . Electrical pathway  406  generally extends from the frame  350  and up to the extension strip  360 , and can be a wire or an electrical trace. Generally, sensor  402 B is positioned outside of the extension strip  360  between the extension strip  360  and the user’s forehead. Sensor  402 B can be electrically connected to the electrical pathway  404  at the backside surface of the extension strip  360 , or the electrical pathway  404  may protrude slightly from the backside surface (e.g., as a wire) to electrically connect with the sensor  402 B. Thus, data generated by the sensor  402 B can be transmitted via the extension strip  360 , the frame  350 , and the connector  370 . 
     In the illustrated implementation, sensor  402 C is a contact sensor that contacts the user’s temple (such as an EOG sensor) when the user interface  300  is worn by the user. Sensor  402 C is electrically connected to the connector  370  through the frame  350 , a first electrical pathway  408 A, and a second electrical pathway  408 B. The first electrical pathway  408 A can generally be the same as or similar to electrical pathway  406 , and thus extends from the frame  350  up to the extension strip  360 . However, the first electrical pathway  408 A is connected to the second electrical pathway  408 B, which extends through the upper strap  314 A. In some implementations, the transition between the first electrical pathway and the second electrical pathway  408 B can utilize magnets, as illustrated in  FIG.  8   . In other implementations, the upper strap  314 A is looped through an aperture in the extension strip  360 , and magnets are not used. In these implementations, the first electrical pathway  408 A may end in a wire extending from the extension strip  360  toward the upper strap  314 A. The wire may then extend into the upper strap  314 A, thus beginning the second electrical pathway  408 B. 
     The second electrical pathway  408 B extends toward the user’s temple, where it electrically connects with the sensor  402 C. Similar to sensor  402 B, sensor  402 C can be positioned between the user’s temple and the upper strap  316 A. Sensor  402 C can be electrically connected to the second electrical pathway  408 B at the backside surface of the upper strap  316 A, or the second electrical pathway  408 B may protrude slightly from the backside surface (e.g., as a wire) to electrically connect with the sensor  402 C. Thus, data generated by the sensor  402 C can be transmitted via the upper strap  316 A, the extension strip  360 , the frame  350 , and the connector  370 . 
     The system  100  can also include sensors configured to determine if the user is sleeping on their back or on either side. In some implementations, sensors can be placed in the user interface  124  or the conduit  126  that measure relative airflow between different sides of the conduit  126 . If the user is sleeping on their side, one of the sensors will measure less airflow relative to the other side, which enables the system  100  to determine which side the user is sleeping on. If the air between the sensors is generally equal, the system  100  can determine that the user is sleeping on their back. This information can, in some examples, be used to provide an estimate of the integrity or wear and tear on the mask. 
     In some implementations, existing electrical wires that may be inside the conduit can be used with user interface  300 . For example, the conduit may include two wires coupled to a thermistor, which can be used as a temperature sensor. The thermistor can be removed, and these two wires can be electrically connected to the connector, in order to transmit data from the one or more sensors  390 . In another example, the thermistor is retained but the connector is configured to bypass the thermistor and electrically connect to the two wires. In yet another example, the conduit may include wires used to heat air flowing through the conduit. These wires can be used instead as a voltage source (for example by attaching a voltage regulator component such as a Zener diode) to power the one or more sensors  390  or any other sensors or components in the user interface  300  that require power to operate. 
     In some implementations, the airflow through the conduit and the connector  370  can be used to power the one or more sensors  390  and any other components. In these implementations, a small power generator can be placed in the conduit or the connector  370 , in the path of the pressurized air flowing through the conduit and the connector  370 . The air flowing through and past the power generator can be used to generate some or all of the required power. In some of these implementations, the power generator includes a turbine that spins as the air flows through the conduit and connector  370 , to thereby generate power. Other implementations can include a thermoelectric generator that converts heat flux to electricity. The power generator can include nanomaterials. 
     The one or more sensors  390  (which can generally include one or more of the sensors  130 , or other sensors) can be used for a variety of different purposes. In one implementation, the one or more sensors  390  are used to detect mouth leak (e.g., pressurized air entering the noise and exiting through the mouth without entering the user’s throat, trachea, or lungs). In this implementation, sensors located in the cushion  330  and/or in the frame  350  can be used to detect air leaking from the user’s mouth. These sensors could include a pressure sensor (such as pressure sensor  132 ), a flow rate sensor (such as flow rate sensor  134 ), a CO 2  sensor, an O 2  sensor, an acoustic sensor, a microphone, or any other combination of sensors. 
     Generally, many respiratory therapy devices that can be used to provide respiratory treatment to a user during a sleep session contain their own sensors to measure various parameters. However, user interface  300  can be used on conjunction with a respiratory therapy device that does not contain any separate sensors. In these implementations, the respiratory therapy device includes a housing defining an inlet and an outlet, and has a blower motor within the housing that is in fluid communication with the inlet and the outlet. The respiratory therapy device also includes a control system with one or more processors that execute machine-readable instructions stored on a memory device to cause the blower motor to flow pressurized air out of the outlet. However, because any required sensors can be placed in the user interface  300 , the respiratory therapy device does not include its own sensors. 
     For example, pressure sensors and flow rate sensors are often used in respiratory therapy devices to monitor operation of the blower motor and the amount of air that is being delivered to the user. Because the user interface  300  can include a pressure sensor and a flow rate sensor, the respiratory therapy device does not need its own pressure sensor and flow rate sensor. The pressure sensor and the flow rate sensor of the user interface  300  can generate data related to the respiratory therapy device and/or the user of the respiratory therapy device, and that data can be transmitted via the user interface  300  and a conduit fluidly connecting the user interface  300  and the respiratory therapy device. The control system of the respiratory therapy device can use the data from the pressure sensor and the flow rate sensor to operate the blower motor. 
     Generally, any of the above techniques or features for electrically connecting components can be used in other locations on the user interface  300 . For example, the strap assembly  310  could have only straps that couple to the frame  350  using magnets. In another example, the strap assembly  310  could have only straps that couple to the frame  350  by looping through apertures in the frame  350  and the extension strip  360 . In still other example, the lower straps  316 A,  316 B could loop through apertures in the frame  350 , while the upper strap  314 A,  314 B couple to the extension strip  360  using magnets. In still other example, the frame  350  may not have the extension strip  360 , and thus the upper straps  314 A,  314 B are coupled to the body  352  of the frame  350 , closer to the lower straps  316 A,  316 B. 
     Further, the user interface  300  is not limited to the specific number or arrangement of electrical contacts in the connector  370 , the frame  350 , or the strap assembly  310  as is illustrated. The user interface  300  can generally include any arrangement of electrical contacts and electrical pathways through the various components, in order to place the one or more sensors  390  in their desired locations while also electrically connecting each of the one or more sensors  390  back to the connector  370 . For example, the frame  350  and connector  370  could each include single electrical contacts for a single sensor, multiple sets of electrical contacts for a single sensor, more or less than four electrical contacts for any number of sensors, etc. Finally, any of the one or more sensors  390  can be located in any suitable location in the strap assembly  310  or in other portions of the user interface  300 . 
     In other implementations, the various electrical pathways are not formed by wires or by traces on or in the various parts of the user interface  124  or the conduit  126 , but instead are wireless electrical pathways or inductive electrical pathways. Wireless electrical pathways can use energy harvesting and wireless communication. Inductive electrical pathways can utilize magnetic fields and/or electrical fields. 
     In some implementations, the strap assembly  310  includes hollow tubes that extend around the user  210 ’s face. The hollow tubes can generally have all of the same characteristics as the upper and lower straps  314 A,  314 B,  316 A,  316 B, except that they are hollow along their entire length. Any wires or sensors can then be positioned within the hollow tubes that make up the strap assembly  310 . 
       FIGS.  9 A and  9 B  illustrate a perspective view and an exploded view, respectively, of a user interface  500  that can include a variety of different sensors according to aspects of the present disclosure. The user interface  500  includes a strap assembly  510 , cushion  530 , a frame  550 , and a connector  570 . The strap assembly  510  can be coupled to the frame  550 , and when the user dons the user interface  500 , the strap assembly  510  is be positioned generally about the back of the user’s head, such that the user’s head is positioned between the strap assembly  510  and the frame  550 . The cushion  530  can be attached to lower ends of the frame  550  so that the cushion  530  is positioned near the user’s face when the user dons the user interface  500 , so that the cushion  530  forms a seal on the user’s face. The connector  570  is configured to be inserted into an aperture in the frame  550 , to thereby couple the connector  570  to the frame  550 . The conduit  126  of the respiratory therapy system  120  can be coupled to the other end of the connector  570 , to thereby connect the respiratory therapy system  120  to the user interface  500 . In other implementations, the connector  570  can be optional and the frame  550  can alternatively connect directly to conduit of the respiratory therapy system. 
     The user interface  500  is configured to deliver pressurized air from the conduit  126  of the respiratory therapy system  120  to the user through the cushion  530  and the frame  550 , or more specifically, to the volume of space around the mouth and/or nose of the user and enclosed by the cushion  530 . In the illustrated implementation, the user interface  500  includes hollow portions  552 A and  552 B to provide two passageways for the pressurized air that fluidly connect the cushion  530  to the connector  570 . In this manner, the cushion  530  is in fluid communication with the interior of the connector  570 . When the user dons the user interface  500 , the hollow portions  552 A and  552 B will generally be positioned on either side of the user’s head/face. In other implementations, the user interface  500  may only include one of the hollow portions  552 A and  552 B to provide a single passageway for the pressurized air, with the other portion being a solid portion that does not form a passageway for the pressurized air. In still other implementations, both portions  552 A and  552 B can be solid, and the frame  550  may one or more tubes (or other hollow portions) that form one or more passageways for the pressurized air between the connector  570  and the user’s mouth and/or nose. Thus, in the implementation of  FIGS.  9 A and  9 B , the conduit  126  of the respiratory therapy system  120  is generally attached to the frame of the user interface at the top of the user’s head, instead of in front of the user’s face. 
     The user interface  500  can include a variety of different electrical pathways, similar to user interface  500 . For example, the connector  570  can be similar to the connector  370 , and include electrical contacts on the end of the connector  370  that are configured to mate with the conduit  126  of the respiratory therapy system  120 . The connector  570  can also include annular electrical contacts at the opposite end of the connector  370  that are configured to mate with the frame  550 . The frame  550  in turn can be similar to the frame  350 , and include electrical contacts near the end of the frame  550  that mate with connector  570 . Thus, the electrical contacts in the frame  550  and the connector  570  allow an electrical connection to be made between the conduit  126  of the respiratory therapy system  120  and the frame  550 . Electrical pathways can then be formed from the frame  550  to a target area for a sensor, through any desirable path. For example, wires or traces can extend from the frame  550  to the user’s face; from the frame  550 , through the strap assembly  510 , and to the user’s face; from the frame  550 , through the cushion  530 , and to the user’s face; from the frame  550 , through the strap assembly  510  and the cushion  530 , and to the user’s facer; or from the frame  550 , through the cushion  530  and the strap assembly  510 , and to the user’s face. In this manner, the frame  550  can be physically and electrically connected to the strap assembly  510 , and the connector  570  can be physically and electrically connected to the frame  550 . Similar to use interface  300 , sensors can be positioned in generally any target area on the user or around the user, and electrical connections can be formed to the sensors using any of the components of the user interface  500 . 
     The one or more sensors  390  of the user interface  300  or of the user interface  500  can include a variety of different sensors in different locations to accomplish a variety of different sensing tasks. In some implementations, the one or more sensors  390  includes one or more EEG sensors that contact a portion of the user’s head, which could include the user’s forehead and/or scalp. The EEG sensors measure electrical activity associated with the user’s brain (e.g., brain activity), and can be used to detect sleep stages and/or to detect micro sleep arousals. The EEG sensors could also be implemented in an earbud positioned in the user’s ear, which can additionally be used to monitor sound and temperature. The one or more sensors  390  can include multiple EEG sensors contacting a variety of different areas on the user’s scalp, which can then be used for quantitative EEG, also referred to as brain mapping. 
     In some implementations, the one or more sensors  390  includes one or more ECG sensors configured to measure electrical activity of the user’s heart (e.g., cardiac activity). The ECG sensors can measure the difference in electrical activity between different portions of the user’s, such as between different portions of the user’s head, between the user’s ears, between the user’s chin and one of the user’s ear, etc. 
     In some implementations, the one or more sensors  390  includes one or more EOG sensors configured to measure movements of the user’s eyes. The EOG sensors can thus be used to detect when the user is moving their eyes, which in turn can aid in determining when the user is in a REM sleep stage. 
     In some implementations, the one or more sensors  390  includes one or more EMG sensors configured to measure electrical activity of the user’s muscles. The EMG sensors can be placed near muscles in the user’s face to detect facial movements. For example, the EMG sensors can be placed near the user’s jaws to detect jaw movement, which can be indicative of the user grinding their teeth during a sleep session, also known as bruxism. Jaw movement detected by the EMG sensors (and/or other muscle activity) can also be used to aid in determining whether the user is experiencing a seizure. 
     In some implementations, the one or more sensors  390  includes one or more microphones that can be used to detect a variety of different sounds, such as breathing sounds (e.g. mouth or nose breathing), noises from the user interface (which can occur if the user interface moves during the sleep session, such as when the user moves), background noises, noises caused by air leaking from the user interface, etc. The microphones can also be used to determine if any detected air leaks are intentional and due to the operation of any vents in the user interface, or if the detected air leaks are unintentional and due to a poor seal between the user and the user interface. A breathing signal can be derived from the microphone data, which can indicate the quality of the user’s breathing (e.g., normal, slow, fast, raspy, wheezing, whistling, etc.). In some implementations, the microphone can be implemented as an earbud positioned in or near the user’s ear, which could also be used as an EEG sensor and a temperature sensor. 
     In some implementations, the one or more sensors  390  includes one SpO 2  sensors configured to measure the user’s peripheral oxygen saturation. The SpO 2  sensors can be placed in a variety of locations, including near the user’s ears, nose, lips, and/or forehead. The SpO 2  sensors can be reflective sensors or transmissive sensors, and can utilize, in some implementations, green LEDs and/or red LEDs. 
     In some implementations, the one or more sensors  390  includes one or more GSR sensors configured to measure electrical properties of the user’s skin (also referred to as electrodermal activity, or EDA), The GSR sensors can be located on the user’s face, and can aid in determining the user’s emotions, performing lie detection, and performing sleep analysis. 
     In some implementations, the one or more sensors  390  includes one or more motion sensors, which can include accelerometers, gyroscopes, magnetometers, inertial measurement units (IMUs), or any combination thereof. The motion sensors can be used to measure activity (such as movement during the sleep session), the user’s gait if walking, fall detection (for example if the user is elderly and at risk of falling out of bed or falling when walking), etc. The motion sensors can be used to measure movements of the user due to the user breathing (e.g., the user’s chest rising and falling during respiration), which can in turn be used to derive a breathing signal. The motion sensors can measure the rate of movement to determine the breathing rate; can detect the user’s chest struggling to move during breathing which can be indicative of an obstructive sleep apnea; and can detect when the chest is not moving at all due to a central sleep apnea where the user’s brain does not signal to breathe. The breathing signal can indicate the quality of the user’s breathing (e.g., normal, slow, fast, raspy, wheezing, whistling, etc.). In some implementations, the motion sensors can be used to determine if there is any movement of the user interface on the user’s head, which can indicate that the user interface does not fit properly. This determination can also be based on data from tension sensors, which can represent the tension in the straps of the user interface, and whether the user interface is tightened properly on the user’s head. In some implementations, the motion sensors can be used to determine the user’s position in bed, which can aid in determining whether the user interface is improperly fitted and causing leaks or poor air flow. 
     In some implementations, the one or more sensors  390  includes one or more analyte sensors that can be used to detect analytes in the user’s breath, such as ketones. The analyte sensors can thus be used to perform breath sampling and analysis. The analyte sensors can also detect analytes in the air, and thus can be used to perform air quality analysis. 
     In some implementations, the one or more sensors  390  includes one or more pressure sensors that can be used to determine the pressure of the pressurized air delivered to the user’s airway. These pressure sensors can be placed in the user interface closer to the user’s mouth and/or nose than pressure sensors in the conduit  126  or in the respiratory therapy device  122 , and thus can in some implementations provide a more accurate measure of the pressure of the pressurize air. 
     In some implementations, the one or more sensors  390  includes one or more RF sensors, one or more sonar sensors, one or more flow sensors (which can be in addition to or as an alternative to any flow sensors in the respiratory therapy system  120 ), one or more temperature sensors (which can be used to measure the user’s core temperature at the user’s temples or in the user’s ears, or the temperature of the user interface), one or more heart rate sensors (which can be used to measure the user’s heart rate, for example at the user’s temples), and others. The temperature sensor can be implemented as an earbud positioned in or near the user’s ear, which could also be used as an EEG sensor and a microphone. The heart rate sensors can include PPG sensors, RF sensors, or even motion sensors that are able to detect motion caused the user’s heartbeat (such as movement of the user’s chest or movement due to a pulse in a vein or artery). 
     The one or more sensors can be used for a variety of different applications. In some implementations, the one or more sensors  390  can be used to perform polysomnography (PSG), which measures a variety of body functions while the user is asleep. PSG can use EEG sensors to measure brain activity, ECG sensors to measure cardiac activity, EOG sensors to measure eve movements, EMG sensors to measure muscle activity, and other sensors. PSG is commonly conducted during sleep studies, and thus aspects of the present disclosure allow a PSG to be conducted using a user interface that the user will already be wearing during their sleep session. Because of the electrical pathways that can be formed in the user interface that is already being worn by the user, the sensors required to perform PSG can be attached and/or positioned near the patient as needed through the user interface. 
     In some implementations, the one or more sensors  390  can be used for emotion mapping. The one or more sensors  390  can detect a variety of different characteristics, including facial expressions and body positions, that may be relevant to the user’s emotional state. The one or more sensors  390  can also be used to detect spontaneous emotions versus forced emotions. The user’s heart rate and breathing rate detected by the one or more sensors  390  can also be used to determine the user’s emotional state, as they can be indicative of the user’s stress levels. Speech detected by the one or more sensors  390  can also be used to aid in determining the user’s emotional state. Data from galvanic skin response sensors can also aid in determining the user’s emotional state. 
     The data from the one or more sensors  390  can be used to test for conditions other than the sleep-related condition that the user uses the respiratory therapy system  120  to treat. For example, the data can be used to determine if the user had any underlying conditions such as atrial fibrillation, which may be evidenced by intermittent cardiac abnormalities, breathing abnormalities, etc. The data from the one or more sensors  390  can also be used to determine the level of the user’s cognitive functioning, including checking for signs of early onset Alzheimer’s, dementia, and other cognitive abnormalities. The data from the one or more sensors  390  can also be used to determine the user’s level of drowsiness, which can be connected to conditions such as the cold or flu, or other chronic diseases. In some implementations, the data from the one or more sensors  390  can be used to detect any discomfort or pain being experienced by the user, and to determine potential causes of the pain/discomfort (e.g., a specific body or neck position may be painful to the user during the sleep session). In some implementations, the one or more sensors  390  can be used to detect various characteristics of the user’s bedroom (or any other room that the user may be in during the sleep session). For example, a sonar sensor could be used to identify and map physical features of the room. In some implementations, the data from the one or more sensors  390  can be used to provide feedback to the user after their sleep session. The feedback can include providing the user with the data itself, and/or analysis based on the data. By using the one or more sensors  390  to detect and monitor these other conditions, the user interface  300  and/or the user interface  500  provide a more efficient mechanism for detecting and monitoring other conditions in users who suffer from these other conditions, and/or require other therapies to treat these other conditions. 
     In some implementations, the user interface may include one or more actuators configured to perform functions based on data from the one or more sensors  390 . The actuators can be used to adjust the fit of the user interface on the user (for example by tightening or loosening the strap assembly, or by re-positioning the user interface relative to the user’s face), to wake up the user during the sleep session, or to perform any other desired function. 
     In some implementations, the user interface may include components to power the one or more sensors  390  separate from any power provided by the respiratory therapy system  120 . The user interface can also include one or more communication interfaces (e.g., transmitters, receivers, transceivers, data ports, etc.) that allow the data generated by the one or more sensors  390  to be transferred and stored independently from the respiratory therapy system  120 . Thus, the user interface can in some implementations form an independent sensor suite that is able to independently generate and transfer data. 
     One or more elements or aspects or steps, or any portion(s) thereof, from one or more of any of claims  1 - 69  below can be combined with one or more elements or aspects or steps, or any portion(s) thereof, from one or more of any of the other claims  1 - 69  or combinations thereof, to form one or more additional implementations and/or claims of the present disclosure. 
     While the present disclosure has been described with reference to one or more particular embodiments or implementations, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present disclosure. Each of these implementations and obvious variations thereof is contemplated as falling within the spirit and scope of the present disclosure. It is also contemplated that additional implementations according to aspects of the present disclosure may combine any number of features from any of the implementations described herein.