Ultrahuman Ring AIR Teardown

2024-06-23 | By bekathwia

Today we’re looking at the Ultrahuman Ring AIR, a biometric tracking smart ring. The device consists of two parts: the ring and the charging base. It also comes with a charging cable, but no charging brick. That’s a benefit in my opinion, since I already have plenty of AC adapters lying around.

The ring has a flat part inside that lines up with the flat part on the charging base. Ultrahuman provided two rings for this video, so big thanks to them for being down for this destructive and reverse-engineering type of review, which they did not get to influence otherwise.

Ultrahuman Ring AIR Teardown

Thanks to David Cranor for lending his EE expertise and to Lumafield for the 3D scan of the (ring) and the charging base.

The thicker part of the ring is home to the components for sensing your heart rate. It’s got some LEDs that shine through your skin, then a photodiode detects how much light reflects off your blood, which changes along with your pulse.

Ultrahuman Ring AIR Teardown

Tools used in this teardown:

So, then I began the teardown process in earnest, starting with the charging base. I saw a seam between the top and bottom of the base and figured I’d try to pry the thing apart at the seam.

Well, it turns out that was an unnecessary move since the base is held together with screws. They’re just covered up by this bottom sticker. I caused a lot of mutilating damage to the plastic before I realized this mistake.

Ultrahuman Ring AIR Teardown

Once I unscrewed the screws, I was left with a small red square circuit board with flex PCB elements attached.

Ultrahuman Ring AIR Teardown

Next up it was time to take apart the ring. I wised up and peeked at the scans before beginning this time, so I could avoid cutting through the battery.

I used my jewelry bench and a triangular file to cut two notches in the titanium shell. Then I was able to pry the shell off by sticking my flat pliers in the notch and twisting.

I was left with the circuit embedded in epoxy resin, which I peeled apart in some places. Since the plastic is very clear, it made sense to leave it in place where it wouldn’t easily separate, so I could still read the printing on the components.

Ultrahuman Ring AIR Teardown

The Ultrahuman Ring AIR has an inductive charging system, much like the Oura Ring we previously explored.

Ultrahuman Ring AIR Teardown

Inside, we found an intricate flex PCB, including a photodiode for heart rate sensing and an array of LEDs. The LEDs, prominently green and red, play a key role in accurate heart-rate monitoring.

Ultrahuman Ring AIR Teardown

We also found a Nordic NRF 52 series chip, known for its Bluetooth features, and its associated chip antenna with a telltale rounded trace connecting the two.

Here are all the components we could identify: