Re: Sensors for doors & windows & ...

["Frank Mc Alinden" <frankmc@xxxxxxxxxxxxxxxx>]

Hi Chris

> up to twelve sensors per board sounds pretty useful !

Gerrys pcb only has only provision to connect 4 sensors .....To connect
more
sensors you would have to solder wires to the appropiate pins on the
pic....

Frank


----- Original Message -----
From: "Chris Hunter" <cjhunter@xxxxxxx>
To: <ukha_d@xxxxxxx>
Sent: Saturday, October 27, 2007 10:50 PM
Subject: Re: [ukha_d] Sensors for doors & windows & ...


> 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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