Beddit vs. Emfit QS

Dan_Dascalescu · October 4, 2015, 2:57am

Has anyone tried the Emfit QS sleep monitor? It’s marketed as in a higher sensitivity class than the Beddit, and the readout shows indeed a lot more data, including Heart Rate Variability (HRV).

I’ve used both for a while, albeit irregularly, and not under optimal conditions (very large mattress, + partner, while the strips are intended only for one sleeper). The overall impression was that the devices generally agreed, though sometimes gave conflicting readouts, and sometimes mis-classified sleep for non-sleep and counted non-existed bed exit events. The Beddit was repeatedly surprisingly accurate at detecting when I fell asleep.

Here are two screenshots that I’ve matched on the time axis. The sleep stage identification coincides among the two pretty well.

ejain · October 6, 2015, 3:49pm

I have been using both devices for a while now, but haven’t done a proper comparison yet. I also noticed that the Beddit works very well for detecting when I fall asleep, but it rarely detects when I wake up…

Dan_Dascalescu · December 14, 2016, 5:48am

I’ve started looking at some Emfit QS plots. The first that jumped out was that it thought I was asleep while I was actually watching a movie in bed and moved around quite (I know, not the best sleep hygiene - blame the girlfriend ;)). Anyway, the Emfit band covers only half the bed and I was roughly in the middle.

This seems to be a data interpretation problem rather than a sensing one, because breathing was clearly detected only after I actually went to sleep around 2:45AM:

Toss & turn detection confirms that:

This false positive is quite common. Here is another Sunday afternoon movie:

Notice how no breathing was detected:

I’ll reach out to the Emift CEO with this feedback - maybe they can adjust their sleep phase detection algorithm to consider no breathing = awake.

Caroline17 · December 30, 2016, 2:27pm

Does anyone have any experience getting data out of the emfit? It seems like I can only download one day at a time.

lotusflyer · January 10, 2017, 3:32am

Hi, I use Sense https://hello.is – which is “OK” just based on “eye-balling” the data but the EMFIT (esp. the integrated HRV measurement) looks pretty interesting. Any experience with that aspect?

Dan_Dascalescu · January 17, 2017, 4:07am

I wouldn’t recommend the Sense.

Justin_Lawler · January 17, 2017, 2:01pm

Has anyone had any success downloading the data from emfit site? Still seems like can only download one day at a time still

I’m thinking of using a screen-scraper to download multiple days - anyone else done this either?

Thanks,
Justin

ejain · January 31, 2017, 10:03pm

gist.github.com

https://gist.github.com/ejain/0b2fed983394742e33eee0416c4e2fce

emfitqs.py

import io, re, requests, sys, time, zipfile

def get_device(token):
  r = get("/api/v1/user/get", token)
  device = r.json()["user"]["devices"]
  print("Device: " + device, file = sys.stderr)
  return device

def list_presences(token, device):
  r = get("/v4/presence/{0}/latest".format(device), token)

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Dan_Dascalescu · February 1, 2017, 8:18am

Very cool Eric, thank you!

Since gist comments don’t send comment notifications, it’d be great to put that code in a regular repo, so people can submit PRs/file issues/ask questions.

ejain · February 1, 2017, 5:33pm

The lack of comment notifications is surprising, but this is a one-off script I don’t intend to maintain or support. If anyone has any questions, here and now is the only opportunity

Justin_Lawler · February 6, 2017, 7:52am

That is fantastic, just what I was looking for. Thanks Eric!