Abstract: Disclosed are devices and methods for estimating blood pressure, which implement a pulse-transit-time-based blood pressure model that can be calibrated. Some implementations provide reliable and user friendly means for calibrating the blood pressure model using blood pressure perturbation methods and multiple sensors.

Abstract: Sleep tracking systems and techniques for monitoring two or more co-sleepers in a single bed are disclosed. Such systems and techniques may incorporate sleeper identification, as well as various non-user-specific aspects. Some implementations may incorporate user-specific or user-tailored alarm functionality.

Abstract: Disclosed are devices and methods for estimating blood pressure, which implement a pulse-transit-time-based blood pressure model that can be calibrated. Some implementations provide reliable and user friendly means for calibrating the blood pressure model using blood pressure perturbation methods and multiple sensors.

Abstract: Sleep tracking systems and techniques for monitoring two or more co-sleepers in a single bed are disclosed. Such systems and techniques may incorporate sleeper identification, as well as various non-user-specific aspects. Some implementations may incorporate user-specific or user-tailored alarm functionality.

Abstract: One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.

Abstract: Disclosed are devices and methods for estimating blood pressure, which implement a pulse-transit-time-based blood pressure model that can be calibrated. Some implementations provide reliable and user friendly means for calibrating the blood pressure model using blood pressure perturbation methods and multiple sensors.

Abstract: In some implementations, a device includes light emitter(s) to emit first light having a first wavelength and second light having a second wavelength. The device also includes light detector(s) to generate a first electrical signal while the light emitter emits the first light, a second electrical signal while the light emitter emits the second light, and a third electrical signal while the light emitter is not emitting light. The device also includes ambient light cancellation circuit(s) to generate a countering signal to counter a portion of one or both of the first and second electrical signals based on the third electrical signal. The device also includes analog to digital converter(s) to generate first and second digital signals based on values of the first and second electrical signals, respectively. The device further includes a controller to determine a saturation of peripheral oxygen metric based on the first and second digital signals.

Abstract: Techniques for measuring ion related metrics at a user's skin surface are disclosed. In one aspect, a method for operating a wearable device may involve determining, based on output of one or more ion selective field effect transistor sensors, various physiological conditions such as a state of hydration, a state of skin health, or the cleanliness of the wearable device or an associated garment.

Abstract: Techniques for measuring ion related metrics at a user's skin surface are disclosed. In one aspect, a method for operating a wearable device may involve determining, based on output of one or more ion selective field effect transistor sensors, various physiological conditions such as a state of hydration, a state of skin health, or the cleanliness of the wearable device or an associated garment.

Abstract: Techniques for measuring ion related metrics at a user's skin surface are disclosed. In one aspect, a method for operating a wearable device may involve determining, based on output of one or more ion selective field effect transistor sensors, various physiological conditions such as a state of hydration, a state of skin health, or the cleanliness of the wearable device or an associated garment.

Abstract: Techniques for measuring ion related metrics at a user's skin surface are disclosed. In one aspect, a method for operating a wearable device may involve determining, based on output of one or more ion selective field effect transistor sensors, various physiological conditions such as a state of hydration, a state of skin health, or the cleanliness of the wearable device or an associated garment.

Abstract: In some implementations, a device includes light emitter(s) to emit first light having a first wavelength and second light having a second wavelength. The device also includes light detector(s) to generate a first electrical signal while the light emitter emits the first light, a second electrical signal while the light emitter emits the second light, and a third electrical signal while the light emitter is not emitting light. The device also includes ambient light cancellation circuit(s) to generate a countering signal to counter a portion of one or both of the first and second electrical signals based on the third electrical signal. The device also includes analog to digital converter(s) to generate first and second digital signals based on values of the first and second electrical signals, respectively. The device further includes a controller to determine a saturation of peripheral oxygen metric based on the first and second digital signals.

Abstract: One innovative aspect is directed to heartrate data collection. In some implementations, a circuit includes a light detector for generating a detected signal based on received light. The circuit includes a switching circuit configured to receive a first signal based on the detected signal and to switch among a first and a second configuration. In some implementations, the circuit includes a first and a second sampling circuit for sampling a value of the first signal when the switching circuit is in the first configuration and second configurations, respectively. In some implementations, the circuit includes an ambient light cancellation circuit for countering a first component of the first signal while the first switching circuit is in the first configuration. In some implementations, the circuit includes an adjustable gain circuit for adjusting a gain of the first signal while the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heartrate data collection. In some implementations, a circuit includes a light detector for generating a detected signal based on received light. The circuit includes a switching circuit configured to receive a first signal based on the detected signal and to switch among a first and a second configuration. In some implementations, the circuit includes a first and a second sampling circuit for sampling a value of the first signal when the switching circuit is in the first configuration and second configurations, respectively. In some implementations, the circuit includes an ambient light cancellation circuit for countering a first component of the first signal while the first switching circuit is in the first configuration. In some implementations, the circuit includes an adjustable gain circuit for adjusting a gain of the first signal while the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heartrate data collection. In some implementations, a circuit includes a light detector for generating a detected signal based on received light. The circuit includes a switching circuit configured to receive a first signal based on the detected signal and to switch among a first and a second configuration. In some implementations, the circuit includes a first and a second sampling circuit for sampling a value of the first signal when the switching circuit is in the first configuration and second configurations, respectively. In some implementations, the circuit includes an ambient light cancellation circuit for countering a first component of the first signal while the first switching circuit is in the first configuration. In some implementations, the circuit includes an adjustable gain circuit for adjusting a gain of the first signal while the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heartrate data collection. In some implementations, a circuit includes a light detector for generating a detected signal based on received light. The circuit includes a switching circuit configured to receive a first signal based on the detected signal and to switch among a first and a second configuration. In some implementations, the circuit includes a first and a second sampling circuit for sampling a value of the first signal when the switching circuit is in the first configuration and second configurations, respectively. In some implementations, the circuit includes an ambient light cancellation circuit for countering a first component of the first signal while the first switching circuit is in the first configuration. In some implementations, the circuit includes an adjustable gain circuit for adjusting a gain of the first signal while the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.

Abstract: One innovative aspect is directed to heart rate data collection. In some implementations, a circuit includes a light detector for generating a first electrical signal based on received light. The circuit includes a switching circuit, having a first and a second configuration, configured to receive a first voltage signal based on the first electrical signal and to switch among the first and the second configurations. The circuit includes first and second sampling circuits for sampling a value of the first voltage signal when the switching circuit is in the first configuration and second configurations, respectively. The circuit includes an ambient light cancellation circuit for generating a current signal to counter a first component of the first electrical signal when the first switching circuit is in the first configuration.