Existing Applications who can measure your sleepphase

Sleep Cycle is a app which measures the sleep cycle. This app can measure your sleep phase on two manners. The first one is with a microphone. Your smartphone determines on basis of the sound you produce during your sleep in which sleep phase you are. You’ve to place your phone like this:

The second manner is with an accelerator. Now, your smartphone determines on basis of your movements during the sleep in which sleep phase you are. You’ve to place your phone like this:

Calibration

Sometimes, you need to calibrate your smartphone one or two nights. This, because the microphone or accelerometer will be to sensitive. For example, you don’t only measure your movements or sounds, but also the vibrations and sound of a passing truck.

Sleeping with two persons

Some Apps claims that they can measure the sleepphase of a single person when he sleeps together with someone else. They give the following explanation:

Sound decays exponentially with distance. So the sound generated by your partner will have a much lower volume than the sound generated by yourself. This makes it possible to determine where a sound originates from with an accuracy of 30 cm.

References

Sources (three App’s)

[1]

[2] Pillow2.0 (App), https://neybox.com/pillow/

[3] [7] Azumio, Sleep Time (app), http://support.azumio.com/customer/en/portal/topics/667008-sleep-time/articles