Re: Re: Sensors for doors & windows & ...

["Rob Iles" <rob.iles@xxxxxxxxx>]

I think shaft encoders (and my initial design proposal) may be
overkill.

I'm looking into a number of possibilities at the moment, and will post
some
clearly defined thoughts (that'd be a first!) in the next few days.

*IF* I come up with something I feel is sensible, would aby of you be
willing to test it? (I'm renting property in a listed building, which means
I can do very little in terms of screwing things to doors/windows etc - -
it's sticky pads/velcro/retrofit everywhere!) Any volunteers?

Cheers,

Rob


On 10/29/07, Karam Karam <kzkaram@xxxxxxx> wrote:
>
>   I'm pretty sure the Maxbotix sensors have analogue output variants -
> so you could interface 4 at a time into IDRANet via the QAI (4x
> analogue input) modules. What are you trying to achieve overall?
>
> Karam
> IDRATEK LTD
>
>
> --- In ukha_d@xxxxxxx <ukha_d%40yahoogroups.com>, Chris Hunter
> <cjhunter@...> wrote:
> >
> > Gerry's boards ... presumably as in :
> >
> > http://www.rgbled.org/maxbotix/index.html
> >
> > up to twelve sensors per board sounds pretty useful !
> >
> > our PC has four RS232 sockets, one maybe two being spare ... so
> could
> > be good for us, too (assuming I can link to Cortex) ... !
> >
> >
> > Chris
> >
> >
> > On 27 Oct 2007, at 12:23, Kevin Hawkins wrote:
> >
> > > I'm intending using some of the Maxbotix ultrasonic sensors
> pointing
> > > slightly diagonally across the doorways. These then provide
a
> > > direction
> > > indication for a person moving into or out of a room (short
to
> > > long or
> > > long to short reading) and based on distance you can elimate
> outside
> > > false trips. I use Gerrys boards, only played so far but
seems
> > > viable,
> > > fortunately I have deep doorways in walls often 3 foot
thick. .
> A
> > > top
> > > mount sensor might even identify people based on height- or
the
> dog .
> > >
> > > I also have some Pulsor -strain sensors arriving any day now
-
> which I
> > > hope to use on the stairs and a couple of doorways.
> > >
> > > K
> > >
> > > Chris Hunter wrote:
> > >>
> > >>
> > >> 'thinking of sensors for doors & windows ... and the
limitations
> of
> > >> the reed-switch (just open or closed & no certainty
on what it's
> > >> telling about the door, unless perhaps it's attached to
the
> locking
> > >> mechanism in some way - which can't see how to do as a
retro-
> fit) ...
> > >> was trying to think how else ... strain-gauge ... laser
+
> mirror ...
> > >> all have just-as-bad limitations ... hmmm ...
> > >>
> > >> 'wonder if PIRs are all the same ... obviously not, but
in the
> sense
> > >> of being designed to pick-up just movement .... are
there some
> that
> > >> are designed to pick-up position, say, or presence not
associated
> > >> with movement, or movement of hard but not soft objects,
or ... ?
> > >>
> > >> with MHVR, having doors or windows open might be
expected to
> affect
> > >> the pressure in the house ... so, all closed => some
> pressurisation,
> > >> maybe, depending on the relative speeds of the inlet
& outlet
> > >> fans ... 'wonder if adding air-pressure-sensor(s) to
each room
> could
> > >> be useful ... picking-up both level & fluctuations
... and so
> doors
> > >> open, people moving-about, curtains wafting, pesky
flies,
> > >> whatever ...
> > >>
> > >> micro-phones are air-pressure sensors, of course ...
wonder if a
> > >> broad or limited bandwidth one would be best ...
> > >>
> > >> hmmm ... would fuzzy logic be the thing, to make it work
...
> looked-
> > >> up Wiki, but 'am really none the wiser, 'though it did
mention
> > >> pattern recognition as being an application for it ...
> > >>
> > >> rambling, sorry, but I feel there's a glimmer here !
> > >>
> > >> or maybe I'm clutching at straws ...
> > >>
> > >> Chris
> > >>
> > >>
> > >
> > >
> > >
> > >
> > >
> > >
> >
>
>
>


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