Discussion in 'The Projects Forum' started by keiserandy19, May 19, 2008.

  1. keiserandy19

    Thread Starter New Member

    May 19, 2008
    can anyone give me an idea of where to start and where i can get a schematic diagram for a motion detector/sensor that have a range of 10meters?? do you any idea my fellow friends?? :( it's our lab-project.. help!!
  2. 2ManyHobbies

    New Member

    May 16, 2008
    It might be easier to buy one off the shelf -- unless your project specifically requires you to design one. A motion light from a local big box store comes to mind.

    If you are required to design one, options are vast. Anything from a CCD to radio based would qualify, so it really depends on your needs.
  3. Wendy


    Mar 24, 2008
    I remember a neat design in Popular Electronics about 20 years ago, it used two speakers, one for an ultrasonic oscillator and the other was the reciever. The neat thing is motion caused a sideband (ie, doppler), which could be picked off with a circuit very similar to a simple AM diode radio with an op amp low pass filter and oodles of gain. If there was a low frequency out the op amp, then there was movement out there.

    No direct coupling was necessary between the circuits. The reciever speaker would pick up the other speakers sound and any bounce simultaneously. With the two speakers set up it looked like a stereo, so it was a hidden setup to boot.

    Another really simple technique is to take the video out of a camera and intigrate it. There there is a sudden change in the picture it will show up as a signal on the output of the intigrator. Think op amp intigrators.
    Last edited: May 19, 2008
  4. SgtWookie


    Jul 17, 2007
    There are several DIY kits on this page:
    Take a look at kit 80-620. It just contains the movement sensor, a movement detector IC, and a couple of Fresnel lenses. It comes with a good bit of documentation and a couple of schematics on how you might wire it up.