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Python client for the $20 Colmi R02 smart ring

tahnok.github.io

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Re: Python client for the $20 Colmi R02 smart ring

#61

Post by wongarsu »

fulafel wrote: post #54

So you just scan for devices and then read? There's no authorization involved, these just publish the readings wirelessly for all interested?

The ring has a very minimal interface. Apart from the sensors - an accelerometer to count steps and two LEDs with photodiode to get heart rate and blood oxygen - there is one status LED on the inside to indicating charging. That's it. The ring is a pure data collection device that basically can't be interacted with without the app.

Maybe they could have required you to hit the ring on a surface to initiate pairing mode. But as it stands the ring will pair with any device that asks for it.

I'm looking forward to someone making a custom firmware for these rings. There is some work in the linked ATC_RF03 project, but I'm not sure if anyone is still working on it

Re: Python client for the $20 Colmi R02 smart ring

#62

Post by wellthisisgreat »

Galanwe wrote: post #25
franga2000 wrote: post #22

Earlier quoted context omitted.

The problem with that idea is that all secure implementations of RFID lock the user out, meaning you can't just buy an NFC ring/fob/implant and copy your bank card or transit card onto it. The only implementations where the user can do that are terribly insecure and, while still commonly used, are slowly getting phased out. So for anything other than systems you control or are good friends with the IT guy for, you're…

Right I agree with you on theory. But in practice, I already do clone most of my smart cards on small NFC stickers on the back of my phone case. The things is 99.9% of access cards (where I leave at least) are default-encrypted mifare classic, making cloning trivial. Transport cards are an other beast since they have their own backlog and proper encryption, but there are ways. So all in all, dumping the card is not t…

Sounds interesting, which sticker are you using?

Re: Python client for the $20 Colmi R02 smart ring

#63

Post by stavros »

edent wrote: post #58
stavros wrote: post #36

Earlier quoted context omitted.

I have a suspicion this is a whitelabeled NFC ring I got from AliExpress for $12. That one includes a T5577 chip and a Mifare tag. You can read and write the Mifare tag with your phone, as normal, and the T5577 with a Flipper Zero or a Proxmark (also from Ali, $40). The NFC tag is a small target, probably because of the size of the antenna, but the RFID one has pretty good range. I got five of those rings, very much…

I think your suspicions are wrong. Those $12 rings will allow you to serve NDEF messages or similar. They won't do U2F, payment, car unlock etc.

It doesn't look like the Z1 does payment either, though. I don't know how they do U2F, but it looks like it comes with a custom reader, which is non-standard. I don't know how Tesla unlock works, so I can't say there.

Re: Python client for the $20 Colmi R02 smart ring

#64

Post by HumblyTossed »

alwayslikethis wrote: post #49
stavros wrote: post #40

Earlier quoted context omitted.

I tried blood oxygen and the readings were the same as my pulse oximeter (though it always shows 98%, so I haven't managed to test any other value), but my sleep reporting with the ring would regularly be three or four hours longer than I actually slept, making it useless.

> test any other value Try this: Hyperventilate for a minute or two. Then, make a full exhale and hold it. You should be able to hold your breath for longer than you normally can and during this time you should see the value drop a bit. Be sure to inhale before you start getting dizzy or faint. (Note: do not do this under water)

> (Note: do not do this under water)

Or while operating heavy machinery.

Re: Python client for the $20 Colmi R02 smart ring

#65

Post by cyberpunk »

woadwarrior01 wrote: post #50
bhaney wrote: post #12

Cool. Just ordered one (from Temu, $18) even though I already wear an Apple Watch. Love the idea of having something I can interface with directly and pull realtime data from without having to install some middleman phone app.

I just did the same. I'd love to try augmenting the sleep tracking data from my Apple Watch with the sleep tracking data from this ring. A couple of months ago, I learnt from this YT video[1] that sleep tracking gadgets are all quite inaccurate compared to a proper polysomnography study. But they're all inaccurate in different ways. [1]: https://www.youtube.com/watch?v=mjOYhxLJP90

Right but if it’s the same sensor you are wearing each night you can still learn something from the trends instead of relying on the raw numbers.

E.g there’s a definite motivation kick to drink less when I see what it does to my hrv and sleep trends for days afterwards, while I don’t particularly care about the numbers being all that accurate.

Edit: Oh and turning on afib history in your Apple Watch will make it record like 10x data points which also helps with that. Maybe

Re: Python client for the $20 Colmi R02 smart ring

#66

Post by [deleted] »

cyberpunk wrote: post #65
woadwarrior01 wrote: post #50

Earlier quoted context omitted.

I just did the same. I'd love to try augmenting the sleep tracking data from my Apple Watch with the sleep tracking data from this ring. A couple of months ago, I learnt from this YT video[1] that sleep tracking gadgets are all quite inaccurate compared to a proper polysomnography study. But they're all inaccurate in different ways. [1]: https://www.youtube.com/watch?v=mjOYhxLJP90

Right but if it’s the same sensor you are wearing each night you can still learn something from the trends instead of relying on the raw numbers. E.g there’s a definite motivation kick to drink less when I see what it does to my hrv and sleep trends for days afterwards, while I don’t particularly care about the numbers being all that accurate. Edit: Oh and turning on afib history in your Apple Watch will make it reco…

[deleted]

Re: Python client for the $20 Colmi R02 smart ring

#67

Post by BarryMilo »

daghamm wrote: post #59
stavros wrote: post #41

This is great! I tried to do this because I wanted to add an indicator of my heart rate to Slack, so people would see if I'm pissed off, but I could never get the data from the ring. I'm very curious to see how the author does it.

This has the unintentional effect of people knowing when you fall asleep in meetings.

Hope it stops updating after business hours!

Re: Python client for the $20 Colmi R02 smart ring

#68

Post by michaelt »

fulafel wrote: post #54

So you just scan for devices and then read? There's no authorization involved, these just publish the readings wirelessly for all interested?

The basically-no-authorisation arrangement is somewhat common for modern bluetooth devices.

It's problematic for things like keyboards used for entering passwords - but if my next door neighbour wants to snoop on my living room thermometer or someone wants to snoop on my heart rate strap as I jog past their house? It doesn't seem to be much of a problem, in practice.

In the bad old days of bluetooth, loads of devices without screens would just hard code the pairing code to 000000 anyway. So it wasn't adding much security anyway. Unlike internet-connected devices, it's not exposed to a billion griefers from around the globe at any given moment.

Re: Python client for the $20 Colmi R02 smart ring

#69

Post by michaelt »

petemir wrote: post #42
yjftsjthsd-h wrote: post #16

Earlier quoted context omitted.

Wouldn't a watch do that? Ex. the https://pine64.com/product/pinetime-smartwatch-sealed/ is dirt cheap and its alarms just vibrate the watch.

I guess it depends. My partner still gets woken up by my (smart)watch at the lowest vibration setting.

If your partner gets woken by a watch vibration actuator, I doubt it's possible for you to sneak out of bed without waking them, as your body weighs about 10,000 times as much as that actuator.
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