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  1. #1
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    Reflective area detection - optical lap counter

    Hello,

    I have a device as you can see on the image attached that always is always spinning around an axis. It has a reflective surface that i want to use to detect it and count it as a lap. So, i don't know which kind of optical sensor use or which idea could you give me to do this. I hope to use a microcontroller with ultra low consumption so i would like that all my application remain with this important feature.

    I would like you help me with this. Thanks!

    Click image for larger version. 

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  2. #2
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    Re: Reflective area detection - optical lap counter

    Use any of 100's of photodetectors, IR sensors, LDRs etc to detect reflection. Count the pulses time the pulses. Use Schmitt gates.

    It's simple enough.



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  3. #3
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    Re: Reflective area detection - optical lap counter

    Quote Originally Posted by Rikr09 View Post
    I hope to use a microcontroller with ultra low consumption so i would like that all my application remain with this important feature.
    The flywheel needs to be illuminated if you wish to use optical detection. You must shine a light on it unless there is ambient light present. Light needs to reflect from it exactly onto the sensor. An led (visible or IR) runs on a certain amount of milli-Amps. Ultra low power consumption may not be feasible.



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  4. #4
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    Re: Reflective area detection - optical lap counter

    Optical reflective sensors have both illumination and detection. I would suggest an analog version and detect the relative change in output voltage of the shiny spot vs the other part of the flywheel.

    https://www.digikey.com/products/en/...log-output/546



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