Smart bed, How does it work?

Hi Everyone,

I can't really sleep well at nights and I stumbled upon this bad boy a while ago ( LINK )

So I decided to build my own with arduino. I just don't know what kind of sensors they use that can be implemented inside a sheet. How do they even heat the sheet?

Optimal temperature is it's most important function. Other than that ... "(Luna is) embedded with sensors to detect breathing and heart rate, accelerometers to track sleep patterns and microphones to hear your snoring."

I get no love?