Abstract: Techniques for conduction-based contact detection for physiological sensors are described. In an example, a wearable device includes a contact-based sensor configured to collect physiological data of a user and at least one electrode positioned proximate to the contact-based sensor, such that a contact status of the electrode corresponds to a contact status of the sensor. The wearable device includes a contact detection circuit that is configured to determine a contact condition of the contact-based sensor that indicates whether the sensor is in sufficient contact with the skin surface based on an electrical characteristic of a conduction path between the at least one electrode and a skin surface of the user. In this way, the techniques described herein support reliable detection of sensor contact quality through conduction-based measurements, which enables wearable devices to ensure accurate physiological data collection while optimizing power consumption and improving an overall user experience.

Abstract: Techniques for cuffless blood pressure monitoring with multiparameter correction are described and are implementable to reduce measurement inaccuracies in wearable cuffless blood pressure devices. In an example, a wearable device includes a sensor arrangement to collect physiological timing data indicative of a pulse propagation time along a cardiovascular pathway and a correction sensor that is configured to measure a correction parameter that impacts the pulse propagation time independent of a corresponding change to blood pressure, such as body temperature, skin temperature, perfusion index, hydration level, or muscle activation.  A processor of the wearable device is configured to process the physiological timing data to determine the pulse propagation time and generate a blood pressure measurement based on the pulse propagation time and measurements of the correction parameter.

Abstract: A replaceable overpatch with embedded sensors is described to attach a main body of a wearable device to a skin surface of a user. For example, the main body houses a processing circuit to process physiological data collected by the embedded sensors of the overpatch. A bottom surface of the main body is configured to face the skin surface during wear and a top surface opposite the bottom surface includes a body connection interface. The overpatch is dimensioned to be placed over the main body to secure the main body to the skin surface and includes an overpatch connection interface that is dimensioned to mate with the body connection interface to form an electrical connection between the overpatch and the main body. In this way, physiological data collected by the embedded sensors can be communicated to the processing circuit without interference caused by proximity to the skin surface.

Abstract: Techniques for conduction-based contact detection for physiological sensors are described. In an example, a wearable device includes a contact-based sensor configured to collect physiological data of a user and at least one electrode positioned proximate to the contact-based sensor, such that a contact status of the electrode corresponds to a contact status of the sensor. The wearable device includes a contact detection circuit that is configured to determine a contact condition of the contact-based sensor that indicates whether the sensor is in sufficient contact with the skin surface based on an electrical characteristic of a conduction path between the at least one electrode and a skin surface of the user. In this way, the techniques described herein support reliable detection of sensor contact quality through conduction-based measurements, which enables wearable devices to ensure accurate physiological data collection while optimizing power consumption and improving an overall user experience.