Just about every fitness wearable around tracks your sleep patterns, but none of them track what's happening in the room. Over on Adafruit, they put together a guide to build a system that tracks all kinds of data.
The DIY sleep monitor tracks temperature, humidity, light levels, noise levels, and your heart rate. This way, you can start to pinpoint why you're getting a bad night's sleep, whether it's because the light from a car's headlights keep flooding your room through the window, or just some weird noises.
It's not exactly the prettiest looking little machine around, but it certainly gets the job done. Head over to Adafruit for the full guide.
Designing a Sleep Monitor [Adafruit]