Fall asleep

Hello!
I'm new in arduino and I have just done basic expiriments with leds etc. I'm planning to do a little project, the headpoint is to recognize if someone sitting in a chair for example fall asleep and then send out and alarm.

It will not be that advanced, my idea was that the first sign when someone fall asleep is the nodding. So I thought about using a tilt sensor perhaps placed on head somewhere which sends out an signal when the person nodd, then the alarm goes on. It should be really basic at the beginning then I might improve it. My question is, how many degrees counts as a tilt, and where should i place it on the head to get it work? (And is the tilt sensor the optimal choice)? Well I hope someone could help me.

/Fjantztone.

fjantztone:
My question is, how many degrees counts as a tilt, and where should i place it on the head to get it work? (And is the tilt sensor the optimal choice)? Well I hope someone could help me.

That sounds like a something that you are going to have to experiment with yourself.

but you think the tilt sensor is one way then?

fjantztone:
but you think the tilt sensor is one way then?

I don't know enough about the science of sleep to say.

Your question is extremely specific, so it's going to be hard for people to answer unless they have done a similar project before.

I have a good Idea you can try to hack one of those toys that read your brain waves. I have seen tutorials on MAKE to do it. You can detect when someone's brain waves drop to a certain frequency (lower when in sleep) of course the person would have to have electrode pads on them but thats sounds just as bad as a tilt sensor.

Most tilt sensors will tell you in data sheet how many degrees you have to tilt in order to activate them.

Here's a commercial product that might be a start. Maybe they have some specs on their Web site:

Hope this helps

How about an accelerometer?? An accelerometer breakout board is fairly small and you could have it turn the alarm on if say the Y axis variable moves from its last point by however much the person has to nod...