Sensosr for detecting REM sleep
Hi,
Do any of you knows good sensors for detecting rem sleep?
I'm in electronics engineering so I can work with anything.
I found 3 ways of reliably detecting rem sleep :
Heart rate : R-R power spectrum in the low frequency is quite different during rem sleep
eyes movement : it's in the name, REM, rapid eyes movement.
ECG : just monitor the right signals
Heart rate :
I recently made an optical heart rate sensor working on you finger, forehead or ear lobe.
But it is greatly influenced by movement, plus keeping it 9h on you while you sleep require unconfortable attachment method.
influenced by movement : movement in any of your lim will chance the blood flow and cause false readings.
I wouldn't use an electrical ECG, it has electrodes directly in contact with your skin, too many things can lead to fibrilation.
EOG :
I could make a optical EOG to detect eye movment but you get the same problem than before :
hard to keep in place
unconfortable
However motion artifact can be ignored using a accelerometer, and thus being able when the head is moving.
Electrode based EOG is also out of the question for the same reason than the ECG.
ECG :
Too complex, to get a reliable rem detection you need a lot of electrodes (and dangerous, because electrodes)
commercial ECG like zeo are just not reliable at all.
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Commercial sensors :
I found a wrist optical based sensor for heart rate : mio alpha
but it's expensive, 200$, I have no idea if the heart rate reading is really reliable or not
and I have no idea if it's hackable or not (if the circuit is drowned in epoxy resin I won't be able to do anything).
So if any of you know any other way, or any other sensors.