Rough fall asleep detection to support Intensive Sleep Retraining

You are probably familiar with the research where they found by waking up test subjects right after they fall asleep, they achieved consistent improvements in both sleep onset and duration

Although the research mentions a 24 hour sleep deprived state of very short naps, there is also an extended protocol over a number of weeks, where subjects are awoken only a few times each night and seems to achieve the same result. A currently unavailable ring device, Thim, has been designed to do this for the first hour of sleep time.

To be able to try this via SaA, we need two things:

  1. Detection of actual fall asleep time via actigraphy, heart rate, hrv etc.
  2. A new alarm type to fire after sleep detection event with two configurable options:
    a. Nap length - even though the nap period should be very short (<~5m) this would let us adjust for the unreliability in #1
    b. Don’t re-arm after HH:MM (until then the event would reset & re-arm everytime this alarm fired)