Moderating leaf blower air flow so that it reflects Met weather reports.

I am wanting to do a project where I connect an electric leaf blower up to a computer which moderates the airflow to represent Met weather reports from the web. So, allowing more or less air through depending on say, changes in temperature or something. I am a complete beginner and was wondering how possible/easy this would be and what the best way to go about it would be. Would be grateful for any help/advice!

Thanks! Beth

What power source does your leaf blower use?

I haven't brought on yet as wanted advice first on what kinda power source ect would be best.

What is the total goal of the blowing wind?

Its going to blow some fabric, it's part of an art project.

If its a small dc fan, maybe you can pwm a transistor to drive it the hardest part will probably be telling it the wind speed from the web once you have it you can set a range( say 0-25 mph) and map it to the anlog value(0-255) maybe an easier idea would be to make your own wind speed sensor on the outside and convey the data?

bmoonan-howard: I haven't brought on yet as wanted advice first on what kinda power source ect would be best.

Electric leaf blowers would probably be mains driven which means that electronic speed control is going to need a fair bit of technology. If you can lower your sights a bit to a low voltage DC fan then things get much easier. (All the leaf blowers I've seen have been hideously loud as well, and I imagine it'd take the shine off an arts project if the thing was so loud you couldn't hear yourself think.

okay yeah thats good advice, i could use a dc fan instead. but with regards to getting the windspeed it kinda has to be from the web because its part of the idea,

You might be able to use a light dimmer (600w) or tool speed controller to control the blower, which is turned via a servo. Use an arduino with ethernet shield to read RSS weather feeds to get wind speed.

Or you could put some kind of airflow diverter at the end of the blower and use a motor to move that causing more or less air to blow on the fabric. While you're at it, perhaps changing where the blower aims or using more than one blower would give you more options as to the dynamics your fabric will be affected by.

You could make a DIY air flow damper operated by a servo. Probably could be simply made from cardboard and hot glue.

if yoiu want to go the simple but loud route, get some brush-less motors that are used in rc planes

You could use more than one DC fan, say 1 fan for every 10 knots of wind? Powering 3 computer fans in series, shows how that could be done.

Or you could use fans that has a speed sensor on it and then turn them on and off to get to desired speed. Reading Fan Speed

Looking forward to seeing how you do this.

bmoonan-howard:
…which moderates the airflow to represent Met weather reports from the web.

Hi Beth

The Yahoo API for weather (http://developer.yahoo.com/weather/) can give you the info you need. Your request includes a code for your location (or at least the one you’re interested in) and there are two tags in the response relevant to wind

<yweather:units temperature="F" distance="mi" pressure="in" speed="mph"/>
  <yweather:wind chill="50"   direction="0"   speed="0" />

For your project everything else in the response can be discarded.

With some kind of network shield your Arduino could take care of this request as well as the control of the fan without the need for a computer in the mix at all.

Interesting concept you’ve come up with!
Geoff

Leaf blowers tend to be loud. A $15 box fan from walmart is quiet and has three speeds.

You can also stack two computer fans on top of each other to increase the amount of blow, not sure if more would have any more benefit than two.
Computer some fans can be powered from 9v to 24vdc with 58 CFM, 4350 RPM, 80 mm Fan.1 80 CFM 2

Of if you need some real grunt. 600 CFM @ 0.000-In SP, Voltage 115 AC, 60 Hz, Single Phase. 3 A bit harder to control as it would require a relay that you turn on and off to vary the speed.
Could hack up a fan speed detection system to have greater control over the fan speed.

Or there is the model aircraft fans and controllers a 4 and Fans(push force of maybe 3-5 kilos)

thanks strykeroz, that yahoo api is exactly what i need!! And yeah i have discarded the leaf blower idea in exchange for a fan after people pointed out it would be very loud, which is true…i’m in the UK so don’t have Walmart but sure i will find something similar.

In the US you can get a rotary knob incandescent light dimmer for ~$5, which might control the speed of the fan. The dimmer knob could be rotated with a servo.

have a look at this project too. it might not help with the technical details (unless you asked Tao himself) but it might help your thinking....

http://www.taogvs.org/VirtualHoleWindMain.html

http://www.kontejner.org/virtual-hole-english

personally, i think making a test before embarking on the main piece is always a good idea. with this in mind i'd grab an old computer fan or two and start experimenting with PWM.

Yeah I am currently in the process of experimenting with dc fans and PWM. The 'virtual hole' is really cool, gave me a lot of inspiration, thanks for directing me to it!