Google has unveiled a groundbreaking technology that could enable future Pixel Buds and other ANC (Active Noise Cancelling) earbuds to track a person’s heart rate. The method behind this innovation is known as Audioplethysmography (APG), and it has the potential to revolutionize wearable health monitoring.
Here’s how it works: ANC earbuds emit a low-intensity ultrasound probing signal through their speakers, which then bounces around in the ear canal. The echoes are picked up by on-board feedback microphones and are influenced by tiny ear canal skin displacement and heartbeat vibrations.
Google conducted comprehensive research, involving 153 participants in total, and found that ANC earbuds equipped with APG were able to accurately detect heartbeats with a remarkably low margin of error, around 3.21 percent. Even with music playing and ambient sounds, this technology remained effective, demonstrating its reliability.
One key advantage of APG is that it can function across different skin tones and ear canal sizes, making it inclusive and versatile. However, it is worth noting that APG may be disrupted by body movements, which could limit its implementation in certain scenarios.
The technology offers a compelling alternative to traditional electrocardiograms (ECG) in headphones, avoiding the added costs, weight, power consumption, design complexity, and form factor challenges associated with ECG integration.
The big question now is when we will see APG integrated into the next generation of Pixel Buds or other earbuds. Google has suggested that a simple software upgrade could enable ANC headphones to support APG, but further development is required to enhance its performance during rigorous activities like hiking, weightlifting, and boxing.
Beyond heart rate monitoring, Google’s research indicates that ANC headphones equipped with feedback and feedforward microphones have the potential to open new opportunities in the field of medicine, ranging from monitoring a person’s breathing to diagnosing ear diseases.