Would those imported $20. wireless doorbells work?
The main problem is false triggering.  Maybe others here can
give some suggestions - my first thought is a mercury switch
that feeds some simple logic (555/PIC?)  Set the switch so it
is made when vertical or upside down.  If the switch is made for a long
time,
the person is in trouble.  If the switch is making intermittently, the
person is walking,
moving etc. and that's OK.  The transmitter is small enough - could be
clipped to
a belt.  I have wired the receivers to a relay for other projects - finding
a logic level
signal in the receiver is fairly easy with a scope.  You could use this
signal
if the alarm was not loud enough or you wanted to trigger a phone
dialer, louder alarm, ect.  Another company called Linear makes longer
range transmitters/receivers - used for wireless security for example.
Mike

> ----------
> From:         White Horse Design[SMTP:whd@ZETNET.CO.UK]
> Sent:         Friday, August 14, 1998 4:35 PM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Body worn transmittor/wireless/alarm if wearer falls over
> project
>
> Can anyone help with this (UK based) ??
>
> At 20:57 14/08/98 +0100, you wrote:
> >Hello Adrian,
> >
> >Not sure whether you can help me as this is not exactly your line
> >(but you might know 'a man who can').
> >
> >I'm looking for a small body worn transmittor which will send a signal
> >to a receiver which will sound/flash an alarm if the wearer falls over.
> >
> >The person in need is a young lady with Learning Disabilities and
> >epilepsy - so the Lifeline style phones won't help as she may well not
> >be able to press the pendant/clip on button.
> >
> >She lives with her parents on a small holding and likes to go see the
> >animals - parents don't like having to keep tabs as it doesn't give her
> >any independance.
> >
> >I'm sure such things exist but can't find any references as most people
> >are on the phone systems.
> >
> >Sorry to trouble you, but I thought you may be able to point me in the
> >right direction.
>
> You need to contact the BCS (British Computer Society) Disability group.
> An
> ex-colleague of mine, Ruben Ashkenazy designed an LCD based cpu system
> with
> a buzzer to remind patients to take their medication.
>
> I'll look out their number and contact details.
>
> Regards
>
> Adrian
> ---
> WWW    WWW   Adrian Gothard
> WWW WW WWW   White Horse Design
> WWWWWWWWWW   +44-385-970009 (Mobile/SMS), +44-118-962-8913/4 (voice/fax)
> WWWW  WWWW   whd@zetnet.co.uk, http://www.users.zetnet.co.uk/whd
> ---
> Developers of GPS satellite-based tracking systems for
> vehicles/helicopters
>