room occupied detection

[OrangeGummyTree]

I've been thinking about this issue myself for a long time now. I
agree, motion detectors completely fail in this respect.

I think there are, in fact, at least five expensive ways to do
occupancy detection right now. Including software to monitor video
feeds, radar and sonar based circuits.

Unfortunately, no off the shelf, low cost, self-contained 'presence'
detector circuits seem to exist. I think the best solution would be a
low cost, low-resolution, thermally tuned CCD (on a chip device). I
think some CMOS devices were recently created that could be perfect
room-to-room, indoor presence detection. Your going to have to DIY
though, no one else is.

Another design option would be coils above ceiling combined with some
intelligent PC based signal analysis to distinguish not just 'is'
someone in the room, maybe even tell who or how many. Somewhat similar
circuit to a metal detector

Two other complex approaches include: 1. Using a comparator circuit
analyzing ambient RF from multiple antennas, or; 2. sub-audible
frequency analysis. Perhaps some 'breathing' clues outside of our
hearing range.

RF transponders badges or RFID are the easy choices. Though these are
the least desirable options. They would require 'tagging' of your
clothes or body.

There seems to be little innovation in HA or at least not on a consumer
level. Maybe this is because so many designs are priced out of a mass
audience hands.

[Andrew Burgess]

"OrangeGummyTree" <ProperPlace@gmail.com> writes:

>I've been thinking about this issue myself for a long time now. I
>agree, motion detectors completely fail in this respect.

Me too :-)

>I think there are, in fact, at least five expensive ways to do
>occupancy detection right now. Including software to monitor video
....
>Unfortunately, no off the shelf, low cost, self-contained 'presence'
>detector circuits seem to exist.

I've seen wired cameras for around $10 each and there is motion detection
software that costs nothing (Motion for linux). You are right that it isn't
off-the-shelf :-(

> I think the best solution would be a
>low cost, low-resolution, thermally tuned CCD (on a chip device).

Hard to say. Room temperature changes with time. Maybe less than visible
light video but you probably have to solve the problem for either to make
them workable...The Motion software does allow masking of areas so you
could omit eg a window with an active street scene

....
>2. sub-audible
>frequency analysis. Perhaps some 'breathing' clues outside of our
>hearing range.

I like the _audible_ audio schemes to detect occupancy, you're going to have
voice activated home automation eventually right? :-) And its built in to many
cameras...

Be extreamly cool if a video based HA system could distinguish different
home occupants!

[Dan]

What about pressure sensors such as the SureAction sensors? I have
deployed 1 zone so far (kitchen), and they will detect when someone is
in the kitchen even if that person isn't moving. They mount underneath
the joists and connect to a zone controller, which can connect to an
Ocelot or any other device which can connect to the NC/NO contact
closure outputs.

As for audio, what would happen if the TV is left on but no one is in
the room (due to phone call or someone at the door)?

dan


OrangeGummyTree wrote:
> I've been thinking about this issue myself for a long time now. I
> agree, motion detectors completely fail in this respect.
>
> I think there are, in fact, at least five expensive ways to do
> occupancy detection right now. Including software to monitor video
> feeds, radar and sonar based circuits.
>
> Unfortunately, no off the shelf, low cost, self-contained 'presence'
> detector circuits seem to exist. I think the best solution would be a
> low cost, low-resolution, thermally tuned CCD (on a chip device). I
> think some CMOS devices were recently created that could be perfect
> room-to-room, indoor presence detection. Your going to have to DIY
> though, no one else is.
>
> Another design option would be coils above ceiling combined with some
> intelligent PC based signal analysis to distinguish not just 'is'
> someone in the room, maybe even tell who or how many. Somewhat similar
> circuit to a metal detector
>
> Two other complex approaches include: 1. Using a comparator circuit
> analyzing ambient RF from multiple antennas, or; 2. sub-audible
> frequency analysis. Perhaps some 'breathing' clues outside of our
> hearing range.
>
> RF transponders badges or RFID are the easy choices. Though these are
> the least desirable options. They would require 'tagging' of your
> clothes or body.
>
> There seems to be little innovation in HA or at least not on a consumer
> level. Maybe this is because so many designs are priced out of a mass
> audience hands.
>

[Andrew Burgess]

Dan <haguru@gmail.com> writes:

>What about pressure sensors such as the SureAction sensors? I have
>deployed 1 zone so far (kitchen), and they will detect when someone is
>in the kitchen even if that person isn't moving. They mount underneath
>the joists and connect to a zone controller, which can connect to an
>Ocelot or any other device which can connect to the NC/NO contact
>closure outputs.

A mic close to the floor will detect walking, though detecting a stationary
weight on the floor, as you mention, does sound very cool!

OB HA Fantasy: With an analog output instead of on/off you could even tell
where the dog was sleeping

>As for audio, what would happen if the TV is left on but no one is in
>the room (due to phone call or someone at the door)?

The HA software _knows_ when the TV is on :-)

And when the phone rings and when someone is at the door, and mutes the TV in
those cases anyway :-) :-)

[Dan]

Andrew Burgess wrote:
> Dan <haguru@gmail.com> writes:
>
>
>>What about pressure sensors such as the SureAction sensors? I have
>>deployed 1 zone so far (kitchen), and they will detect when someone is
>>in the kitchen even if that person isn't moving. They mount underneath
>>the joists and connect to a zone controller, which can connect to an
>>Ocelot or any other device which can connect to the NC/NO contact
>>closure outputs.
>
>
> A mic close to the floor will detect walking, though detecting a stationary
> weight on the floor, as you mention, does sound very cool!
>
> OB HA Fantasy: With an analog output instead of on/off you could even tell
> where the dog was sleeping
>
>
>>As for audio, what would happen if the TV is left on but no one is in
>>the room (due to phone call or someone at the door)?
>
>
> The HA software _knows_ when the TV is on :-)
>
> And when the phone rings and when someone is at the door, and mutes the TV in
> those cases anyway :-) :-)
>
This is where I introduce you to Murhpy's Law, especially when you are
married ;)

[L. M. Rappaport]

On Mon, 03 Jan 2005 00:26:39 GMT, Dan <haguru@gmail.com> wrote (with
possible editing):

>What about pressure sensors such as the SureAction sensors? I have
>deployed 1 zone so far (kitchen), and they will detect when someone is
>in the kitchen even if that person isn't moving. They mount underneath
>the joists and connect to a zone controller, which can connect to an
>Ocelot or any other device which can connect to the NC/NO contact
>closure outputs.

So far as I know, pressure sensors are the only commercial solution
available today. Of course, they don't work under a slab.

--

Larry
Email to rapp at lmr dot com

[Robert L. Bass]

>> What about pressure sensors such as the
>> SureAction sensors? I have deployed 1
>> zone so far (kitchen), and they will detect
>> when someone is in the kitchen even if
>> that person isn't moving...

Hmm. I've only used SureAction on a few sites. The ones I used employed a
piezo device to detect movement of the floor joists when someone walked
above them. They did not detect someone's mere presence unless he was
walking about. Perhaps this is something different...?

> So far as I know, pressure sensors are the
> only commercial solution available today.
> Of course, they don't work under a slab.

They also won't tell you that someone is lying on a couch watching TV.

--

Regards,
Robert L Bass

=============================>
Bass Home Electronics
2291 Pine View Circle
Sarasota · Florida · 34231
877-722-8900 Sales & Tech Support
http://www.bassburglaralarms.com
=============================>

[Dan]

Robert L. Bass wrote:
>>>What about pressure sensors such as the
>>>SureAction sensors? I have deployed 1
>>>zone so far (kitchen), and they will detect
>>>when someone is in the kitchen even if
>>>that person isn't moving...
>
>
> Hmm. I've only used SureAction on a few sites. The ones I used employed a
> piezo device to detect movement of the floor joists when someone walked
> above them. They did not detect someone's mere presence unless he was
> walking about. Perhaps this is something different...?
>
>
>>So far as I know, pressure sensors are the
>>only commercial solution available today.
>>Of course, they don't work under a slab.
>
>
> They also won't tell you that someone is lying on a couch watching TV.
>
I haven't tried that yet, but it's next on my list. But as far as I
know, these sensors measure how much the joists is 'flexing'. When there
is no 'pressure', the sensors return back to the state they were in when
they were first installed (which I assume is why you have to take the
resistance measurements once they are installed, so you can callibrate
your system).

Eventho they tell you not to place these under furniture, I would think
if you place them close, that the added weight of sitting down close to
a sensor would also trigger this sensor. I do know that the kitchen
sensors I installed will detect when someone is in the kitchen, even if
that person isn't moving. Avertised coverage area of one sensor is
about 4'x8', but I placed some of mine closer. I still have some
adjustments to make, but I am impressed so far.

dan

[L. M. Rappaport]

On Tue, 25 Jan 2005 00:14:08 -0500, "Robert L. Bass"
<robertlbass@comcast.net> wrote (with possible editing):

>>> What about pressure sensors such as the
>>> SureAction sensors? I have deployed 1
>>> zone so far (kitchen), and they will detect
>>> when someone is in the kitchen even if
>>> that person isn't moving...
>
>Hmm. I've only used SureAction on a few sites. The ones I used employed a
>piezo device to detect movement of the floor joists when someone walked
>above them. They did not detect someone's mere presence unless he was
>walking about. Perhaps this is something different...?

Yes, the ones I'm talking about are based on weight, not movement.
They are not piezo, they are strain gauges. Also, I'm not sure they
are SureAction - the job I used them was a long time ago. They're a
real PITA to setup and they need to be recalibrated every time you
move the furniture. Not worth it, IMO, but OP's mileage may vary.

>> So far as I know, pressure sensors are the
>> only commercial solution available today.
>> Of course, they don't work under a slab.
>
>They also won't tell you that someone is lying on a couch watching TV.

Actually, they will. But subject to the conditions above.
--

Larry
rapp@lmr.com