Wind Speed Sensor

Discussion in 'General Electronics Chat' started by nanobyte, Jun 3, 2006.

  1. nanobyte

    Thread Starter AAC Fanatic!

    May 26, 2004
    Hi everybody. I currently in the process of designing a senior project (an intelligent house system) in college. I need a sensor that detects wind speed and either outputs a corrresponding voltage or corresponding number of pulses per a unit time based on the speed of the wind. The sensor would have to be small, because it has to be mounted on a small scale model house. I have been looking all over the internet, but can not find anything that suits by purpose. Does anyone know where I can find and/or order the sensor I need?
  2. n9352527

    AAC Fanatic!

    Oct 14, 2005
    How small is small?

    These are several different anemometer design that I know of:
    - Three cups (usually fitted with Hall sensor) - simple and cheap.
    - A tube and a ball, vacuum action - inaccurate.
    - Pitot tube - hard to read, rugged.
    - Heated thermocouples - difficult to calibrate and interpret, expensive.
    - Ultrasonic - difficult to read, expensive.

    It depends on your budget, and how far you would compromise on the size.
  3. hgmjr

    Retired Moderator

    Jan 28, 2005
    Another solution that might be effective is the use of an optical based shaft encoder.

  4. beenthere

    Retired Moderator

    Apr 20, 2004

    Must it be in scale with the house, or do you just need windspeed over the model?

    Any anemommeter will do for the latter, and thay homebuild easily. But you do have to do a calibration run to make use of the output. Any small DC motor and the cups made from ping pong balls will do the trick.

    For something more in scale, a differential pressure sensor working in a passage through the house would work. Same principle as a pitot tube for aircraft airspeed. Helps to have the wind always from the same direction, though.
  5. thingmaker3

    Retired Moderator

    May 16, 2005
    Goldmine Electronics had some surplus pressure sensors that could be used in a pilot-tube knock-off.

    The pilot tube could have vanes on the back for pivoting into the wind, but would than need slip-rings.

    Another idea might be to use a vertical windmill with tachometer. (Hall effect or optical would do for the tach, as has been previously suggested.) Try an internet search on "Persian windmill."
  6. nanobyte

    Thread Starter AAC Fanatic!

    May 26, 2004
    I like the first option that n9352527 gave which was three cups (usually fitted with Hall sensor) - simple and cheap. n9352527 could you are anybody else give me more information or point me in the direction where I can get more information on this this type of wind speed sensor.
  7. thingmaker3

    Retired Moderator

    May 16, 2005
    "Anemometer" is the term to use for an internet search! B)
  8. billbehen

    Active Member

    May 10, 2006
    How fancy do you need? A micromachine pressure sensor with a sail (small flat piece of card) might be enough. Mount it on a roof surface, angled back facing the wind.