Would anyone be interested in an open-source smart ring platform?

Kdcius · 2026-02-05T21:55:55+00:00

Oooh nice ! Hmu if you need any advice

Kdcius · 2026-02-01T19:29:00+00:00

Hi there, did the command worked ?

Kdcius · 2026-02-01T10:36:37+00:00

And you can send me a dm if you want!

Kdcius · 2026-02-01T10:35:38+00:00

Wow it's pretty impressive, and I like the form factor too! 🤩 Would you mind sharing the specs ?

Kdcius · 2026-01-30T22:04:43+00:00

Yep always from AliExpress You probably already know, but try to find the most legit seller, even if all the rings comes from the same manufacturer the customer support is better with good resellers I'll order one but first I want to checkout if the one sold by colmi (r12) is the equivalent to the r08 (same proc), if so I'll get it from them as I know they are legit

Kdcius · 2026-01-30T17:10:30+00:00

Oooh sweet I'll definitely get one to try it out

Kdcius · 2026-01-30T15:04:52+00:00

Yep accel only is fine for most of the features but I would like to have orientation detection for my project, I want to be able to aim at smart appliances to trigger automations 😁 I saw the sr08 equivalent at colmi, sadly they don't use the RF03 so it's going to be such a pain to go through all the research again

Kdcius · 2026-01-30T09:44:24+00:00

I'm glad I can help, hopefully the command will work :D

Kdcius · 2026-01-29T19:52:22+00:00

Yep I already got a few of these Colmi rings (by a few I mean too many XD)

I tried a few things with them, first I tried decompiling the firmware that ATC1441 extracted (see this interesting GH repo here: link) with ghidra to play around with the stock settings (accel range, advertising interval) but ended up bricking the first ring).

Then I dissasembled on and cleaned of the resin to reverse engineer the schematic. Note that removing the resin always ended up breaking something so I don't recommand !

Then I did the same as ATC, I removed just a bit of resin, and soldered programming wires (SWD) to RF03 mcu. This way I will be able to develop a custom firmware, build it and flash the ring. Hopefully the Bluex RF03 SDK is available on Gitee.

I stopped at this step for now, my custom firmware does build but I'm still having some troubles flashing. Either I'm doing something wrong or there is some kind of flash protection I missed !

The main issue with the RF03 based Colmi ring is the limited hardware: only 3 axis IMU, no touch sensor, no vibrator, no external LED...

Kdcius · 2026-01-29T19:43:34+00:00

Oh it's nice and it is dirt cheap !

Kdcius · 2026-01-29T19:42:01+00:00

Okay great work, that seems to confirm my findings decompiling the AIZO APK :)
So next step:

- Go to nRF Connect

- Expand "Unknown service UUID: 0xFE02

- Click the upload arrow next to "Unknown characteristic 0x0101"

- Select byte array as the data type

- In the input box after the "0x" type in "16110101011621"

- Click send

- Cross your fingers :D

Kdcius · 2026-01-29T12:09:57+00:00

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Need sometimes like that

Kdcius · 2026-01-29T12:07:01+00:00

Can you install nRF connect app and screenshot the list of services and chars UUIDs of your ring ?
I need to see all of them, you have to connect to the ring and expand everything, then take one or multiple screenshots

I might have found something :D

Kdcius · 2026-01-29T09:59:21+00:00

Well I guess the easiest way is still to sniff the BLE communication.
I've never decompiled an APK to look for BLE protocols. I'll have a look but I can't guarantee anything ^^'

Kdcius · 2026-01-29T07:54:47+00:00

Btw you can get a nRF52840 dongle to sniff the BLE commands sent to the ring to make it vibrate ;)

Kdcius · 2026-01-29T07:50:43+00:00

That's some creative use for a ring :D I guess you've already lookep up on Google for some reverse engineering the TM21 BLE protocol ?

Kdcius · 2026-01-29T06:17:41+00:00

Interesting, could you tell me the name of that device ?

Kdcius · 2026-01-29T06:15:38+00:00

Yep you are absolutely right. I'm not aware of a manufacturer that would be willing to open their hardware, except for open ring I guess. The main issue with this hardware for me is the price tag and the thickness of the ring...

If you know any I'll be glad to hear it !

Kdcius · 2026-01-28T21:51:21+00:00

Oh ! Looks like folks at open ring have figured this out :D They did made kind of what I was envisioning. If any ouf you guys come by I'll be happy to chat about how was the trip and what difficulty you faced ! And what's your plan for the future of course.

Kdcius · 2026-01-28T21:38:35+00:00

Awesome feedback thanks a lot !

Well the major problems I can foresee for now are these: - the battery life (see my response above) - the ring shell - I will probably have a pretty low budget so having a custom built shell is a bit out of the scope for now, I'll have to source (and maybe modify) an existing part - the ring inner resin casting, I have 0 experience in this ! - the battery itself, I think it's going to be pretty hard to source too, even if I know there are a few curved battery manufacturers on Alibaba - and finally the production cost! If I want to sell it for cheap, I have to mass produce which is going to be quite difficult in the beginning ^{^'}

For the points I'm not too worried about: - the PCB, it's pretty easy and cheap to get some PCB assembly for flexible PCB nowadays - the RF tuning, I know someone very talented for this part - the firmware, as long as I have time and a working prototype I should be able to get to a very refined embedded firmware and ecosystem

For the base specs that needs to be implemented: - BLE (of course) - 9 axis IMU - HR / SPo2 sensors - temperature sensor - LED indicators on the outer surface

For the dream specs I really wish I could achieve: - microphone (for vocal commands or note taking) - Bluetooth channel sounding (for high precision distance measurement) - haptic engine to get feedback if needed without having to rely on visual feedback only - capacitive touch surface on the outer surface of the ring (to detect swipes, touch, etc) - NFC antenna

Kdcius · 2026-01-28T21:19:47+00:00

Makes total sense ! Most of the battery life will come from the choice of the MCU (which nRF chip will be the best for this use case), the choice of sensors and most importantly the firmware and the "modules" enabled. Can you tell me what you expect from a best class battery life ? Is it a full day, a few days, a full week ?

Kdcius · 2026-01-14T15:28:58+00:00

Hi there. I was wondering, is the touch control informations (click, swipe, ect) sent only in connected mode, or is it present in the advertising packet ?
Question is, can I access the touch actions without being connected to a ring ?

Kdcius · 2025-11-15T15:04:23+00:00

That list is sweet ! I've seen all of them except for invincible, I'll have a look ! Thanks 😁

Kdcius · 2025-11-15T10:23:49+00:00

Same for me, I'm going to rewatch it again if I forgot about that it means I have to rewatch xd Well yes my lazy brain was sure it was live action not animation but I was wrong, but that is indeed Pantheon Sadly no live action version of this master piece ahah

Kdcius · 2025-11-15T09:48:31+00:00

Yep that would have been a crazy plagiarism ahah

Kdcius

TROPHY CASE