PIC distance measurement

Discussion in 'The Projects Forum' started by Bluedogfreddy, Sep 24, 2007.

  1. Bluedogfreddy

    Thread Starter New Member

    Sep 24, 2007
    I would like to measure a distance (55ft) electronically and need to be accurate to less than 1/4". - Any thoughts as to what might be hardware could used would be appreciated.
  2. cumesoftware

    Senior Member

    Apr 27, 2007
    I said this a couple of times to others: you should have some ideas. We are here to help but don't expect us to do the entire work. At least give some details about the requirements of your project.

    Hope you don't take this wrong.
  3. Bluedogfreddy

    Thread Starter New Member

    Sep 24, 2007
    No offense taken - I should have been clearer and investigated more thoroughly before posting. I've actually taken a step back and am thinking that i don't require an actual linear measurement but a comparison of the two sides of a triangle (isosceles). I was comtemplating using a stationary ultrasonic emitter to produce a beacon and use 2 recvr's to calculate the diff in time, anyone think a high speed pic could accomplish the task?

    I'm not looking for schematics- just a direction to investigate that may produce the accuracy I'm looking for. (I'm not versed in ultrasound/measurement at all - but will be reading on)
  4. beenthere

    Retired Moderator

    Apr 20, 2004
    If that's a distance to a flat wall, you might do it that way. Your frequency has to be such that you can resolve better than 1/4". At 55', the sound back may be affected by wind and attenuation from the 110' sound path.

    Are you planning on using the PIC to generate the measuring frequency? If so, what amp and emitter are you planning to use? what is the proposed layout of your beacon and receivers?