Silent Alarm Clock!

so there's this guy named Johan Brengesjo who invented this Alarm clock, but not just any alarm clock, this one is silent! There are little bracelets you wear when you sleep and when the alarm clock senses that its time for you to get up, the bracelets activate and vibrate, and can be turned off by removing the bracelets. I think this would be a super idea, especially when your in a building or house with lots of other people, this way if you had to get up early, you could use the vibration alarm, and wake up without disturbing anyone. it would also be a bit less of a bite to wake up to in the morning, rather than a jarring schreeching beep noise every morning!