My last housemate was a nice chap. Still is, by all accounts. I used to regularly (but inadvertantly) annoy him by going away for a couple of days, leaving my alarm clock on. It's a persistent little thing (I need that) and will, given time, disturb anybody, even through a couple of walls. Every now and again, I'd remember in the evening and give him a call. Often though, all he got was a mid-morning apology as I realised that I'd woken him again when he still had two hours to sleep.

What I needed then (and still want now) is an alarm clock that only goes off if I'm at home. To do this it has to, by the simplest possible mechanism, know when I am there. Now, I could mess about with bluetooth and personal area networks but I don't want to get that complex.

Instead, the Alarm Clock Keyfob would be a small piece of plastic that you attach you your keyring and insert into the top of the alarm clock when you're home. An override switch would allow others (not in possession of a plastic keyfob) to use the alarm clock.

A small added advantage is that you always know where your keys are in the morning. A small disadvantage is that you have to remember where your keys are the night before.
-- st3f, Jul 22 2005

For bristolz http://www.thinkgee...odies/lights/788e/`
No biometrics, but it has a different alarm for each day of the week. (I suspect this would solve st3f's problem as well, if he simply didn't set an alarm for Saturdays and Sundays.) [DrCurry, Aug 25 2005]

Or you could have a pressure sensor somewhere on the bed to detect if there is anyone in it. [+]
-- pooduck, Jul 22 2005


[st3f]'s idea is good. [pooduck]'s idea is much better.
-- wagster, Jul 22 2005


And when everyone in the house hears the bed-pressure-sensor alarm clock switching on and off, repeatedly and rapidly, some fine morning; what are you going to tell them all?

[Later] Oh, yeah, something on the topic . . . I remember trying to explain to my machining instructor that the way to prevent us leaving the chuck key in the lathe was to convert the on-switch to chuck-key-operated. I got another safety lecture and a poor grade. You get a croissant.
-- baconbrain, Jul 22 2005


I think a simple PIR sensor could be used to arm the alarm clock. The arm state could be shown by a small lamp. The allowed time slot for arming would be somewhere between, say, 6pm and the setting time for the alarm in the morning. If you don't move about in the bedroom during that time slot, then it won't arm.
-- Ling, Jul 22 2005


My memory is that good old-fashioned wind-up alarm clocks had to be turned on every time. Get one of those.
-- DrCurry, Jul 22 2005


What about us who keep forgetting where a) we don't know where we left our keys or b) forgetting where we left the alarm clock and the keys? (or if you chuck the evil little clocky out the window...)
-- froglet, Jul 22 2005


Maybe you could have a small digital alarm on your key ring.
-- weedy, Jul 22 2005


I'd rather find my keys at the night than in the morning. +

I do think that an inexpensive fingerprint scanner on the alarm clock might be suitable as well. No matter whether fob or biometric, you must remember to set the alarm each evening, though.

The biometric approach adds a wee bit of security that can be used to protect alarm settings or to even set different alarm settings (i.e. left index for standard wakeup time, left thumb for Saturday, little finger for Sunday, etc.).
-- bristolz, Jul 22 2005


What's that word now...ah, yes, "over-engineering."
-- DrCurry, Jul 22 2005


Indeed, and a counterpoise to "under-imagining."
-- bristolz, Jul 22 2005


In my imagination, at least, this could all be done with a bog-standard PDA, no biometrics needed. Whether you attach your keys to it or not.
-- DrCurry, Jul 22 2005


What would be the invention in that?
-- bristolz, Jul 22 2005


Good old-fashioned ingenuity, dear. We don't need to throw silicon at everything.
-- DrCurry, Jul 22 2005


Have you a PDA without silicon?
-- bristolz, Jul 22 2005


*New* silicon.

And for st3f's original problem, no silicon at all - alarm clocks always worked that way, before we started making them out of silicon and plugging them into walls and things.
-- DrCurry, Jul 22 2005


The problem here [DrCurry] is that you require an invention to have an accompanying function that needs fulfilling. As we have solved most simple problems already, you restrict yourself to looking only at the unsolved problems - the hard ones. Because of this you find few inventions that interest you. I think many good inventions aren't really needed.
-- wagster, Jul 22 2005


Vodka, for example.
-- bristolz, Jul 22 2005


Without vodka, how are you going to run your tractor?

baconbrain: A chuck-key operated lathe? Absolutely.
-- st3f, Jul 22 2005


wags: actually, no, I'm just more demanding. If we're going to start using biometics, let's use that technology (now baked) that figures out when you're ready to wake up before waking you. If we're going totally over the top, then let's have the house recognize who is sleeping where, and when to wake them up (and taking account of when one brings home a hottie, and wants more time cuddling before being jolted back to the real world).
-- DrCurry, Jul 23 2005


//I'm just more demanding// - Yes, you are. Good job someone around here is I suppose. While we're on the subject, would your house be able figure out if you've actually brought home a hottie or just drunkenly picked the first minger who said yes? It could invent some 'emergency' if it thought you were about to do something you'd regret in the morning.
-- wagster, Jul 23 2005


<even more overengineering>surely your alarm clock could just have a wireless connection to your online diary, and, noticing you're away from home that night, not bother to ring in the morning.</even more overengineering>
-- neilp, Aug 25 2005



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