Google has offered additional details about the operation of its “loss of pulse” detection feature in the Pixel Watch 3, which could save lives.
In the first half of this month, Google declared that pulse detection would no longer be available for the Pixel 3. The company elaborated on its functionality and development.
According to Google, the Pixel Watch 3’s loss of pulse feature is based on three essential metrics.
The first reason, which is sensible enough, is that the optical heart rate sensor located on the back of the watch seems to identify the loss of the heart rate signal. Alternatively, to quote Google directly, the Pixel Watch detects “a sudden large drop in the alternating current (AC) component of the green PPG.”
Additionally, it utilizes a “machine learning algorithm” that examines the sensor data from the PPG heart rate sensor and accelerometer. Moreover, it evaluates data from an “additional sensor” through LEDs that vary in “geometries, wavelengths, LED currents, and photodiode gain settings.”
The only explanation that truly makes sense is that Google is talking about the sensor that would otherwise indicate your blood oxygen level.
According to Google, it collaborated with cardiac electrophysiologists and their patients to create the loss of pulse feature, as well as the “machine learning algorithm” mentioned in its explanation.
Recreating real-life scenarios in which a person’s heart stops is ethically and practically difficult, making this a crucial aspect of the feature’s development.
The blog provides helpful context to help you understand the significance of the Pixel Watch 3’s loss of pulse feature. It concerns converting an “unwitnessed” out-of-hospital cardiac arrest (OHCA) into a witnessed event.
However, the wearable takes on that role instead of a nearby person. As outlined in the initial report regarding the Pixel Watch 3’s loss of pulse functionality, efforts are undertaken to notify the wearer through auditory cues and haptic feedback prior to placing a call to emergency services.
