On 21/02/2012 8:57 AM, Marcel Duchamp wrote:
> On 2/20/2012 2:42 PM, David Duffy (AVD) wrote:
>> Has anyone here done much work with proximity sensors?  I am looking to
>> trigger an event when someone stands in front of (or walks past) a
>> specific area in a retail environment.  The sensing must be done from
>> one side only (no beam break methods).
>>
> Multiple sensors can be used if you control them all.  Just use time
> division multiplexing - only one on at a time. For the other
> requirements, I would look at IR transmitters/receivers.
>
> What is the penalty for false positives?

That's a fair point about multiplexing the sensors.  I was envisaging a=20
central controller board that processes up to 8 sensors.  Larger=20
installations would have multiple controller boards, or maybe an=20
expander board.

There is no serious consequence of a false positive.
David...

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___________________________________________
David Duffy        Audio Visual Devices P/L
Unit 8, 10 Hook St, Capalaba 4157 Australia
Ph: +61 7 38235717      Fax: +61 7 38234717
Our Web Site: www.audiovisualdevices.com.au
___________________________________________

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