Re: HA Holy Grail #1: Occupancy Detection

[ian.bird@xxxxxxxxxxxxxx]

For this shower problem the ultrasonic range sensors would be good.
You
could mount one on the ceiling and detect when someone was in the shower.
The main challenge would be making it showerproof whilst keeping it
effective. Just a thought

Ian



---------+---------------------------->
"David Gumbrell"
<david.gumbrell@g
mail.com>
Sent by:
ukha_d@yahoogroup
s.com


29/08/2006 22:17
Please respond to
ukha_d

---------+---------------------------->
>-----------------------------------------------------------------------------------------------------------------------------

To:       ukha_d@xxxxxxx
cc:       (bcc: Ian Bird/CV/Novartis)
Subject:  Re: [ukha_d] HA Holy Grail #1: Occupancy Detection
>-----------------------------------------------------------------------------------------------------------------------------





Detecting shower "on" is the tricky part. At the moment I get
reasonable
off-to-on transition detection using an humidity sensor, but the on-to-off
is not so good (shallower curve). I considered a flow sensor, but seems
like
overkill and may reduce the waterflow (and I can't face the plumbing), so
probably will just alter the room timeout when shower off-on detected to
allow for average shower duration and then reset to shorter when redetect
on
exit from shower cubicle. Or just have a 10 minute time-out :-)

I was planning temperature sensors on the CH pipes anyway, so will probably
add one to the shower hot feed too to sharpen the Off-to-on detection a bit
further.