What you need is a trained monkey to jot down notes. Could help grandmother unload as well. cc > On Jun 2, 2008, at 8:40 PM, Jinx wrote: > >> The IR transmitters sound interesting, and would lie somewhere >> between 1 and 2 above, but might be tricky to place so that they >> aren't also blocked by the passengers or cargo > > If an IR transmitter pings into the car space with enough power > it may not matter that something is in the way. And it's unlikely > that something would be in the way as you get closer to the hinge. > People would generally be sitting way back by the door latch, > perhaps a good 60cm from the hinge > > We know how sensitive a VCR receiver is if the transmitter is in > the room, but point the transmittion out the door and it's lost > ----------------- > Is there enough of a round-trip resistance difference in a car > body when a door is open ? > ----------------- > I wonder if ultra-sound might work. If you flooded the car space > with it, would opening a door cause enough of a 'leak' to detect, > over and above the movement of people within ? > ----------------- > Detecting an interior ceiling light would be simple, but getting the > wiring tidy might not be easy for the mechanically-challenged > ----------------- > Most cars now would have a door indicator light on the dash ? > Perhaps tap into its supply or a photo-detector on the dash (not > very aesthetic) > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist