Sounds like I may like to have this for a hobby project that I want to build. Imagine a tripod with a motorized turret on top. Mount on top of it a battery operated, water type, squirt gun. Have the IR heat sensers track the little kid walking by and use ultrasonics to detect range. When the kid gets within range.....ZAP!!! Now imagine putting this directly in front of your friends front door and watch him get into the house. Andrew Hooper wrote: > How about using a Heat Detector.? > > I have a circut floating around that was designed for animals, it detects > not > only the heat when an animal walks past but also detects the direction the > animal was going. > > An IR or RF proximity sensor could also work. > > Regards > Andrw > -----Original Message----- > From: Mauricio Jancic > To: PICLIST@MITVMA.MIT.EDU > Date: Friday, March 31, 2000 2:55 PM > Subject: [OT] people detector, cheap, low consume, and esay to build, is > that too much? > > >Hi people, > > I'm looking for some ideas on how to make a "people detector". The > idea is to make a device that plays a pre-recorded voice message (ISD14000 > series) each time someone is in front (or near) it. > > At the first time, I was thinking on a Datalogic infrared sensor > (abou U$S 120 + 21% (taxes) here in Argentina). But there were two problems: > 1st. The high price in relation to the rest of the circuit. > > 2nd. As it must be battery > powered i make some calc on the total consume and it was too much for me. > According to specifications the sensor consumes 25 to 30 mA (the same that > the isd when playing) and that get's me to a 2.5 weeks with a 12Ah and 12 v > battery. > > > > 3rd. It isn't very nice to > put such device on this simple circuit. > > > > So, wath im looking for is some bright and ease to build ideas on > infrared or ultrasound "spectrum". > > Do you have any?? > > > > Thank in advance, Mauricio.