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(Untitled)

An NguyenAn Nguyen Posts: 10
edited 2010-05-05 18:07 in Accessories
Hi all,
Please tell me what hardware and software we need to buit the ultrasonic translator to capture the wave form from another sensor?

Tahk you for your time.

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2010-05-03 22:36
    You will need to provide more information.· What do you mean by ultrasonic translator?· What do you mean by "capture the waveform"?· What other sensor?
  • An NguyenAn Nguyen Posts: 10
    edited 2010-05-04 14:03
    Hi Mike,

    I'm using the ultrasonic distance transducer to detect object, but it does not work properly in a room that have DT-205 (dual technology motion sensor·- combine PIR and·ultrasonic 40KHz·in one unit). So, I want to build a ultrasonic translator on the ultrasonic distance sensor, it can capture the ultrasonic sound from the DT-205. It is possible or not? do you have any advise?

    Thank you for your time.
  • Mike GreenMike Green Posts: 23,101
    edited 2010-05-04 14:26
    No, it's not possible. You have the DT-205 sensors emitting pulses of sound that fill the room (hopefully) and, somewhere in the room, you have a PING or equivalent also emitting pulses of sound in no particular relationship to the DT-205's pulses. The transducers are not sharply tuned, so they respond to a broad band of ultrasound, so the DT-205 interferes often with the PING's attempts to locate objects.

    To get these two devices to work in the same space, you need for them to work on widely different frequencies and you can't modify either device (not realistically). A frequency translator, while theoretically possible, isn't practical and would be way more complicated than simply duplicating the function of the PING at a different frequency.

    The PING works by measuring the time it takes for the sound pulse to return to it. For it to use the pulses from the DT-205, it would have to know exactly when the DT-205 produces its pulse and the PING would have to "know" where the DT-205 is in the room so it could compensate for the distance and direction of the sound source.

    The simplest solution would be to switch to the use of IR for object detection like that described (and used) in "Robotics with the BoeBot".
  • Spiral_72Spiral_72 Posts: 791
    edited 2010-05-04 15:14
    Mr. Green, A very good response!

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    "puff"...... Smile, there went another one.
  • An NguyenAn Nguyen Posts: 10
    edited 2010-05-05 16:13
    Hi mike,

    Can you tell me more how to duplicate function of ping))) sensor with different frequentcy.

    Thank you for your time.
  • Mike GreenMike Green Posts: 23,101
    edited 2010-05-05 17:08
    No, I can't. It's not a beginner's project. Ultrasonic transducers are made for specific frequencies, so first you'd have to find similar transducers made for a different frequency range. There are some Do-It-Yourself articles on the internet for ultrasonic distance finders and you'd have to find and modify such a design for a different frequency range. It should be easy, but you'd have to understand how they work enough to make the changes yourself. I think it would be a good learning experience, but would take some time and experimenting on your part to do it.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2010-05-05 18:07
    You should edit your original post using the pencil icon to the top right of the message and add a subject line.

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    Chris Savage

    Parallax Engineering
    ·
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