Abstract: Methods, systems, and devices for a wearable ring device are described. A wearable ring device may include a ring-shaped housing and a printed circuit (PCB) that at least partially contacts an inner shell of the ring-shaped housing. Light-emitting components and light-receiving components may be disposed on a first surface of the PCB and may extend through an aperture(s) in the inner shell such that the light-emitting and light-receiving components are substantially flush with an inner ring-shaped surface of the inner shell. Optical lenses may cover the light-emitting and light-receiving components within the aperture(s). In some cases, the optical lenses may be molded over the light-emitting and light-receiving components before the PCB is inserted into the ring-shaped housing. In other cases, the optical lenses may be molded over the light-emitting and light-receiving components (and the aperture(s)) after the PCB is inserted into the ring-shaped housing.

Abstract: Methods, systems, and devices for detecting an orientation of a wearable device are described. The method may include the wearable device transmitting, using a light-emitting component, first light and second light and generating a first signal and a second signal based on the first light and the second light, respectively, received using photodetectors. The first and second light may be associated with first and second wavelengths, where signals associated with the first wavelength are relatively unaffected by varying orientations of the wearable device, whereas signals associated with the second wavelength vary based on different orientations of the wearable device. Further, the wearable device may determine an orientation of the wearable device worn by the user based on a comparison of a first signal and the second signal, and may acquire physiological data from the user via the wearable device using measurement parameters that are determined based on the orientation.

Abstract: Methods, systems, and devices for optical signal measurement are described. A wearable electronic device may activate a first combination of optical sensors, the first combination of optical sensors including a set of transmitter sensors and a set of receiver sensors. In some cases, one or more optical sensor of the first combination of optical sensors may be positioned under a protrusion on an inner surface of the wearable electronic device. The device may measure, at the set of receiver sensors at a first time, one or more signals from the set of transmitter sensors, determine a signal quality metric associated with the one or more signals, and select a second combination of optical sensors for use at a second time based on the signal quality metric.

Abstract: Methods, systems, and devices for determining blood pressure based on a relative timing of pulses are described. In some implementations, a system may include one or more wearable devices configured to measure heartbeats at different locations on the body of a user. The different locations may be different physiological locations (e.g., chest and finger/wrist), and/or different penetration depths at the same physiological location. The system may use the components of the wearable devices to acquire physiological data and to observe one or more heartbeats of the user over a time period. The system may compare pulse observation times observed at the different locations, and may determine a blood pressure metric for the user based on a relative timing of when heartbeats are observed at the different locations.

Abstract: Methods, systems, and devices for identifying representative photoplethysmogram (PPG) pulses are described. A method may include acquiring a first set of PPG pulses from a user via a wearable device. The method may include comparing a set of morphological features of the first set of PPG pulses, and determining one or more PPG profiles for the user, where the one or more PPG profiles each include a set of morphological value ranges for the set of morphological features. The method may include acquiring a second set of PPG pulses from the user via the wearable device, and determining that one or more PPG pulses from the second set of PPG pulses match the one or more PPG profiles. The method may include determining one or more physiological metrics associated with the user based on the one or more PPG pulses matching the one or more PPG profiles.

Abstract: Methods, systems, and devices for optical signal measurement are described. A wearable electronic device may activate a first combination of optical sensors, the first combination of optical sensors including a set of transmitter sensors and a set of receiver sensors. In some cases, one or more optical sensor of the first combination of optical sensors may be positioned under a protrusion on an inner surface of the wearable electronic device. The device may measure, at the set of receiver sensors at a first time, one or more signals from the set of transmitter sensors, determine a signal quality metric associated with the one or more signals, and select a second combination of optical sensors for use at a second time based on the signal quality metric.

Abstract: Methods, systems, and devices for optical signal measurement are described. A wearable electronic device may activate a first combination of optical sensors, the first combination of optical sensors including a set of transmitter sensors and a set of receiver sensors. In some cases, one or more optical sensor of the first combination of optical sensors may be positioned under a protrusion on an inner surface of the wearable electronic device. The device may measure, at the set of receiver sensors at a first time, one or more signals from the set of transmitter sensors, determine a signal quality metric associated with the one or more signals, and select a second combination of optical sensors for use at a second time based on the signal quality metric.

Abstract: Methods, systems, and devices for blood oxygen measurement are described. A method may include receiving, via a wearable device, a first photoplethysmogram (PPG) signal for a user acquired during a time interval using a first set of PPG sensors, and receiving a second PPG signal for the user acquired during the time interval using a second set of PPG sensors that are different from the first set of PPG sensors. The method may include comparing the first PPG signal and the second PPG signal, and determining one or more blood oxygen saturation metrics for the user during the time interval based on the comparison of the first PPG signal and the second PPG signal. The method may include causing a graphical user interface (GUI) to display an indication of the one or more blood oxygen saturation metrics.

Abstract: Methods, systems, and devices for heart rate detection are described. A method for measuring heart rate for a user may include receiving physiological data associated with the user, wherein the physiological data may include photoplethysmogram (PPG) data and motion data collected throughout a first time interval via a wearable device associated with the user. The method may include determining a set of candidate heart rate measurements within the first time interval based at least in part on the PPG data, selecting a first heart rate measurement from the set of candidate heart rate measurements based on the received motion data, and determining a first heart rate for the user within the first time interval based on the selected first heart rate measurement.

Abstract: Methods, systems, and devices for heart rate detection are described. A method may include receiving physiological data associated with the user, where the physiological data may include motion data and temperature data collected throughout a time interval via a wearable device associated with the user. The method may include determining a condition quality metric associated with the time interval based on the received motion data and temperature data. The condition quality metric may indicate a relative quality of the physiological data collected throughout the time interval for determination of heart rate measurements. The method may include sampling photoplethysmogram (PPG) data for the user via the wearable device based on the condition quality metric satisfying a threshold metric value and a timer satisfying a first threshold time duration. The method may include determining a heart rate measurement for the user based at least in part on the sampled PPG data.

Abstract: Methods, systems, and devices for temperature calibration are described. A device may support temperature calibration for a set of temperature sensors. For example, a wearable device may activate a set of temperature sensors associated with the wearable device. The set of temperature sensors may include a primary temperature sensor and one or more secondary temperature sensors. The wearable device may determine a trigger to calibrate the one or more secondary temperature sensors based on one or more conditions, and calibrate the one or more secondary temperature sensors using the primary temperature sensor based on the trigger. Based on the calibrating, the wearable device may process temperature data associated with a user that is received from one or more of the primary temperature sensor or the one or more secondary temperature sensors.

Abstract: Methods, systems, and devices for wearing detection are described. A method may include directing light from a first light emitting element to a first light detecting element via an optical interface, at least one of the first light emitting element or the first light detecting element dedicated to detecting a level of surface contact at the optical interface. The method may include measuring, via the first light detecting element, an amount of escaped light which escaped the optical interface, where the amount of escaped light is indicative of the level of surface contact. The method may further include controlling an activation of a second light emitting element and a second light detecting element based on the level of surface contact, at least one of the second light emitting element or the second light detecting element dedicated to measuring a physiological phenomenon at a user of the wearable device.