Google Unveils Method To Monitor Heart Rate Through Any ANC Headphones
When it comes to measuring heart rate, most people rely on off-the-shelf fitness trackers and smartwatches. But what if you could use your wireless noise canceling earbuds to measure your heart rate as well? Well, that’s exactly what Google has attempted in a research paper spotted by 9to5Mac.
But before we get into Google’s approach, let’s learn how heart rate is typically measured using photoplethysmography. This optical technology detects changes in blood volume using pulsating lights.
Google’s earbuds approach, on the other hand, uses a different technique called audioplethysmography (APG). Unlike the optical method, this technique relies on ultrasound to detect the heartbeat.
According to the paper, Google notes that the APG “transmits a low-intensity ultrasound probe signal through the speakers of the ANC headphones and receives the echoes through the built-in feedback microphones.” Simply put, the ultrasound wave bounces off the ear canal and returns to the microphone. This reading includes complexities such as changes in the shape of the blood vessels, which modulate the ultrasound echoes with the heartbeat.
Google says it has developed a new model that includes a “polyphonic APG signal processing pipeline” that detects both heart rate and heart rate variability in “constrained and unconstrained settings.”
“APG enables effective monitoring of heart activity on mass-market ANC headphones in the presence of music playback and body movement such as running,” Google added. The company also states that APG technology withstands variations in skin tone, optimal sealing conditions and ear canal size.
