Q: Where are you at in the project?
A: I'm in the analysis phase trying to create the "detection and intervention" algorithm. Currently I have the code running on a RasPi3 to gather biometric data at night, and I'm got a Voice Activated Recording application running on a old Android phone to help me identify the times of the (audible) nightmares. I've written a script to parse the VAR output to correlate and graph the nightmare events for analysis.
I've done some work to get a VAR app (svar) running on the RasPi itself, however I've not figured out how to make it record properly so for now I'm still using the Android app.
I did implement a "timed vibration" functionality in the interim, however it's not been particularly successful.
Q: What's the best way to secure the band for sleep?
A: The stock wristband is uncomfortable during sleep, and this was also the case for the other wristbands we've tried. I've constructed a ~40mm wide plastic collar for the main unit of the band out of a piece of soft 1mm thick plastic, lined it with duck tape for softness, then secured that against the skin of the ankle with a dollar-store elastic wrist-support. So far this has worked well.