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Circuits motion detector light assembly 3 way proximity

  1. Oct 8, 2016 #1

    VxP

    User Avatar

    Is it possible to create a series of circuits capable of detecting a moving object with 3 levels of proximity e.g. green light when object is 10ft. away, yellow light at 5ft., red light at approx. 1ft. away, etc?

    Thanks, Dave
     
  2. jcsd
  3. Oct 8, 2016 #2

    anorlunda

    Staff: Mentor

    Yes. The simplest way I can think of is the photo detector method. Simply shoot a beam of light across the path, and sense when the light is interrupted by a passing object. You can have multiple beams at different distances.

    Automatic doors at stores and office buildings and garage door openers use such photo detector circuits.
     
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