Will two side b side Ultrasonic sensors affects each other's receiving signal

Discussion in 'The Projects Forum' started by Ahmed Adel Hosni, Sep 29, 2011.

  1. Ahmed Adel Hosni

    Thread Starter Active Member

    Aug 16, 2010
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    I want to use two ultrasonic sensors side by side. the distance may be 12 cm for example. the sensors will measure the distance between it and an object.

    If the first sensor transmits a wave so that the first receiver can detect it, will the second receiver also detects it ?? or can i adjust them to different frequencies or any other technique to avoid that problem ?

    Thanks
     
  2. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    If both have the same frequency it's very likely that both receivers will give you an output signal. Two transmitters with different frequencies and receivers with band-pass filters to pass only the corresponding frequency will probably work.
    Did you think about what components you want to use, what are available to you?
     
  3. Georacer

    Moderator

    Nov 25, 2009
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    I did a similar project once and even with a viewing angle of 90degrees there was jitter from the echo in the room. I 'd leave a window of at least 50ms between measurements.
     
  4. Ahmed Adel Hosni

    Thread Starter Active Member

    Aug 16, 2010
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    Thanks for your help

    I will be using an Unltrasonic sensor from Parallax

    http://ram-e-shop.com/oscmax/catalog/product_info.php?products_id=1725

    i am confused and i don't know whether it will work side by side or not. according to the datasheet the frequency is 40 Khz.

    Does anyone have a solution or another idea ?? infrared sensors for example ?
     
  5. Georacer

    Moderator

    Nov 25, 2009
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    Since those sensors are packaged together in a single board, it is almost certain that the necessary compensation has been made. Make sure you read its manual before you use it.
     
  6. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    The Ping))) sensor uses a single pin to first enable a measurement, then the Ping))) drives that same pin with a pulse who's width is proportional to the distance of the target.

    If you drive two sensors off the same controller, one will be busy while the other one is idle, so they will typically not cross-drive each other. At worst, you may need some dead time delay between switching sensors.
     
  7. Ahmed Adel Hosni

    Thread Starter Active Member

    Aug 16, 2010
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    right. i thought of generating the pulse of the first sensor and then generate the second pulse after a small delay so they don't conflict.

    I hope this solves the problem.

    Thanks Erniem & Georacer for your efforts
     
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