Invented by Amihood; Patrick M., Fan; Xiaoran, Wortham; Cody, Google LLC

In today’s world, people want to track their health with less hassle. A new patent application brings a fresh way to monitor health through earbuds and headphones, using something called audioplethysmography and motion-sensing data fusion. Let’s break down what this means, why it matters, how it builds on past ideas, and what’s new and clever here.

Background and Market Context

People want to live longer by staying healthy. Tracking health, like heart rate or breathing, helps spot problems early and encourages healthy habits. But most health monitors are bulky, uncomfortable, or get in the way when you move. Some need blood samples or have sensors that make the device heavy and costly. That’s why many people skip using them altogether.

Wireless earbuds and headphones—called “hearables”—are everywhere now. Folks use them to listen to music, podcasts, or talk on the phone. Most people already wear them for hours each day. This opens a door: what if these hearables could also measure your health, without any extra gadgets or making you uncomfortable?

This patent application aims to do just that. It describes how to turn regular earbuds into health trackers by using sound waves and built-in motion sensors. The promise? A way to check your heart rate, breathing, or even detect if you’re talking or chewing, all while you go about your day. No need to strap on a wristband, wear a chest patch, or prick your finger.

The challenge, however, is movement. When you nod, walk, or even chew, it shakes up the readings. The noise from motion can hide the real health signals. This is where combining sound data with motion sensor data comes in—it can help separate the real signals from the noise. That’s the core problem this patent tries to solve, making hearable-based health tracking practical in real life.

Scientific Rationale and Prior Art

Let’s keep things simple. Your ear canal isn’t just for hearing; it’s also a neat place to sense changes in your body. When your heart pumps, tiny blood vessels in your ear expand and contract. This changes the shape and size of your ear canal, even if just by a little bit. If you send a sound wave into your ear and listen to how it comes back, you can pick up these tiny changes. That’s the big idea behind audioplethysmography.

Previous health monitors have used light (like those red lights in fingertip pulse oximeters) or electricity (like chest straps for heart rate). Some tried to use sound, but they often struggled with noise from movement. If you’re sitting still, it’s easier. But if you’re moving your head, talking, or walking, the sound signal gets messy.

Some earlier hearables tried to use microphones and speakers to pick up heartbeats or breathing, but they didn’t deal well with motion. Other health trackers put motion sensors in watches or chest bands. Sometimes, they tried to use these sensors to cancel out noise, but not many did this with sound signals in the ear.

What’s different here is the clear idea of combining two things: the sound signal (from inside your ear) and the motion signal (from a sensor like an accelerometer or gyroscope). By comparing the two, the system can figure out which parts of the sound are real health signals and which are from you moving around. This “data fusion” lets the hearable keep tracking your health, even while you’re active.

Past patents and products often focused on just one sensor or didn’t fuse the data in a meaningful way. This patent stands out by offering several ways to mix and filter the data, making the measurements work in more real-life situations. That includes walking, exercising, chewing, or just turning your head.

Invention Description and Key Innovations

Now let’s get into what this patent actually claims and how it works.

The invention is a method (and a device) that uses both sound and motion to measure things happening in your ear canal. Here’s how it works:

First, the hearable (like an earbud) sends a sound into your ear. It could be a tone or a bunch of tones at once. The sound bounces around inside your ear, and the earbud listens to the echo with its microphone. As your heart beats, your blood vessels and the shape of your ear canal change a little. This changes the echo.

But if you’re moving, the echo also changes because of your motion. That’s where the motion sensor comes in. It records how your head is moving—sideways, up and down, spinning, or tilting.

The invention’s magic is in how it processes these two streams of data. It matches up the timing of the sound and the motion. Then, it uses special filters—sometimes smart ones that adjust themselves—to subtract the noise caused by movement from the sound signal. The result is a cleaner signal that’s mostly just your health data.

This cleaned-up signal can be used to measure your heart rate, breathing rate, or even blood pressure. It can also tell if you’re talking, chewing, or performing certain gestures. The system can even decide when to turn these features on or off, based on how much you’re moving or what activity you’re doing.

Let’s break down some of the clever steps and options described:

– Motion-Artifact Filtering: This is the core idea. When the earbud hears a sound that looks like a heartbeat but also sees that you’re nodding your head, it knows to ignore some of that sound—it’s probably just from moving.

– Different Filtering Techniques: The patent suggests using regular filters that adjust their settings based on motion, adaptive filters that learn what to ignore, and even machine learning models that get better over time.

– Multi-Earbud Systems: If you’re wearing two earbuds, each with its own microphone and motion sensor, they can work together. This means the system can compare signals from both ears, making it even easier to spot real health signals and filter out noise.

– Activity Detection and Classification: Not only does the system clean up the sound, it can also use the motion data to figure out what you’re doing. Are you sitting, walking, running, or talking? Once it knows this, it can adjust its measurements or even control your music and calls.

– Custom Calibration: Everyone’s ear is a bit different, and earbuds might fit better or worse depending on the day. The system can send out a series of sounds to check the best tones and settings for each user and each time they put on the earbuds. This makes the measurements more accurate.

– Real-Time Operation: The whole process happens quickly. The hearable can measure your health and react to your activity in real time, so you get up-to-date feedback or alerts.

– Control and Privacy: The user can decide when to turn these features on or off, and the system is designed to respect privacy by not sending personal data unless you say so.

What does this mean in practice? With these techniques, your earbuds could track your heart rate while you run, tell you if you’re grinding your teeth at night, or notice if you’re talking to someone (and pause your music). It can do all this without extra straps, sensors, or discomfort, and it works even when you’re moving—something most old methods couldn’t handle.

This invention is not just about measuring more things, but measuring them reliably in more of life’s moments. It uses both the sound inside your ear and how you move to paint a clearer picture of your health and activity. That’s a big leap from older methods.

Conclusion

This patent application shows a clear, clever way to make everyday earbuds into powerful, comfortable health monitors. By fusing acoustic and motion data, it promises to give better, more accurate health readings without making life harder for the user. It builds on past science but adds new methods for cleaning up signals and understanding what the user is doing, all in real time.

As hearables become more common, inventions like this could turn them into everyday health companions—helping people live better, healthier lives, all while listening to their favorite tunes.

Click here https://ppubs.uspto.gov/pubwebapp/ and search 20250213142.