Heated carpets exist, as a type of portable radiant heating, and (in smaller format) as foot warmers for under-desk usage.

These devices may be thermostat controlled, but basically consume electricity as long as they're plugged in and turned on.

If pressure sensors were incorporated into a heated rug, it could be designed to turn off within a certain period of time from when it was last stepped on.

To avoid the heat being kept active due to someone leaving a chair on it, the rug could be designed to only pay attention to changes in pressure -- someone stepping on or off.
-- goldbb, Oct 15 2009

[+]
-- FlyingToaster, Oct 19 2009


But what if somebody is standing still on it while someone else walks off hmmm? Or your pet wanders on and off hmmm? or dust accumulation puts enough weight on the carpet to turn it on hmmm? Or the owner of the rug spontaneously combusts hmmm? [+]
-- DrWorm, Oct 19 2009


's that last one we're mostly worried about here.
-- FlyingToaster, Oct 19 2009


Radiant heating is intended to heat the whole room, slowly, not just the area where you are standing. Do you turn off your heating system every time you go out of a room, or leave it on so that the pipes don't freeze whilst you buy fish and chips?
-- vincevincevince, Oct 19 2009


Vince³, do you turn of your electric blanket when you get out of bed in the morning, or leave it on to keep the bed from freezing while you're away at work?
-- goldbb, Oct 22 2009



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