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Controlling Motors with Infrared Light

  1. Nov 12, 2013 #1
    Hi everyone,
    I'm looking to create a circuit where an infrared detector is located above the edge of a small wooden disk with an infrared light also on its edge. I want to wire this up so that while the detector does not see the light, power is supplied to a motor that will turn the small wooden disk (and thus eventually put the infrared light into the detectors angle of view). However, I also want to wire it so that when the detector actually does see light, another, separate motor is activated.

    Is this any way to do this without the use of IC's?

    thanks for reading!
  2. jcsd
  3. Nov 12, 2013 #2


    Staff: Mentor

    It seems like you could do the first part with a power transistor in series with the motor and battery with say a PIR sensor controlling the base of the transistor switching it on/off when light is detected.

    This link may help:


    However, if this is for a real project then you might want to do it with stock components like an Arduino using PIR sensor and servos for fun and flexibility. Alternatively you could replace the Arduino with a Raspberry-Pi.

    As they say in the industry, SMOP: A Simple Matter of Programming
    Last edited: Nov 12, 2013
  4. Nov 13, 2013 #3
    you could do that with a ir transistor and dpdt relay.
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