Wednesday, October 24, 2012

diy anemometer

I was organizing here the other day (a rare thing) and I came across this DIY anemometer (do it yourself wind speed and direction indicator recorder) that I had built in 2002 according to Derek Weston's excellent DIY Rotorvane design. What a nice thing Derek helped me build!

I should be putting it outside but I will do that at the new place. For now it has to be put away. Should run it over the winter to make sure it still works OK? It does not really go anywhere until the spring. Hopefully this winter will be mild but there will be storms and it is a bit of a thrill to see how strong the wind got the night before, for example. I have a great tall post to mount it on which is mostly in the clear. It is in the house's shadow but the wind almost never blows from that direction (usually from the NW here).

This was a very nice DIY project for me with wonderful instructions, software and personal help from Derek via email. His webpage isn't live any more but Chris' site has a very thorough review of Derek's device.

I have just installed the RS232/USB driver and now Derek's software and manual which I'd saved on a CD with the device. It turns out that was a good idea since neither is available on the web. If you need either, let me know by email.

As I write this, I am having trouble getting the anemometer to talk to the computer thru COM1 via the RS232/USB adapter. When I spin the cups, the LEDs on the display track the movement so I can see it is responding correctly but I can't read it from the computer. It only "speaks" RS232 so I need to remember how to do that. I dropped the speed to 1200bps but that does not get it going. Update 10/27: I have it working now with a straight through RS232 cable. Not sure why the RS232/USB adapter does not like it.

By itself, the anemometer will store a months worth of readings and it can be remotely located. Here is a sample of the log in printed form that I was able to produce with Derek's software.

Ten years ago I had assembled the display easily and it worked well. There was a fair bit of fine soldering but no surface mount components which suited me just fine. Many LEDs mount in the board at the same height. It worked on the first try.

Derek's rotor assembly is particularly clever, robust and precise, all at the same time.

I was a bit skeptical of my ability to make the cups out of ping-pong balls as Derek described but I got very respectable results by simply being careful with a very sharp blade. I did a couple trial runs to get a bit of practice. The ping-pong balls were inexpensive and available anywhere thus illustrating an important principle of DIY projects - that the materials should be readily available anywhere and cheap to obtain.

Derek had a great small kit of the circuit board and some of the special parts like the machined spindle and the disk but I am assuming that is no longer available. Derek had explained on his website when you could see it that he had sold the rights to the design to a business and that there were a limited number of the kits available.

Derek, if you are sailing out there somewhere and want to say hello, please write to me! This was a great project - thank you. Nicely done.



Anonymous said...

Hi George,
I'm trying to find some information about Derek Weston's anemometer and your website is the only useful hit I;ve had.
Do you have any design information available? Derek's site is not longer available.
Geoff Steer

George Plhak said...

Hi Geoff. I am afraid you may have reached a dead end with me also. I thought I had a copy of the manual and software but I can't find it now. Sorry about that. Chris' review site seems to be live still - have you asked there?

Anonymous said...

Thanks George,
The email address on Chris' website no longer works so I'll have to try elsewhere.


Unknown said...

This is a very neat DIY wind measuring system. I'd like to build one myself but concede I may have to start from scratch and replicate it. I think the the originator was offered a deal to buy the copy rights to it, and hence DIY info was withdrawn. If so a great loss to the DIY community...

George Plhak said...
This comment has been removed by the author.
George Plhak said...

I found this very complete description of a self-built anemometer with details and rationale at:

George Plhak said...

I received this email from Derek Dec 14 2015:
Hi George,
I'm pleased you were happy with your DIY Rotorvane Anemometer.
All information regarding this project, now including theory and firmware source code, is at
Derek Weston

Margret said...

Hi George, thank you so much for this detailed information! I'm happy to say I just fixed an LED light string by replacing most of the bulbs, however there is one bulb that does not light even when replaced with a known working bulb. The socket doesn't appear to be reversed, though I'm not sure if I'm looking for the right thing. My question is whether I must fix this bulb somehow, as opposed to just ignoring it and enjoying the rest of the string. :) Sounds like leaving it will cause the whole string to fail down the road? Thanks again! --Margret

George Plhak said...

Margaret is commenting on this article You can read her subsequent comment there.