Very low friction potentiometer or encoder

Hi!

I just finished making a prototype wind vane. I used a rotary encoder (like this: http://www.ebay.com/itm/10pcs-New-High-Quality-Rotary-Encoder-Switch-With-Keyswitch-/310911594094?pt=LH_DefaultDomain_0&…) for detection of position, it's got 18 degrees of resolution.

But since it could occationally miss a step when moved around fast to both sides, I added a IR led and IR receiver that is used to calibrate north against the flat side of the rotary encoders shaft, after adding this it has been spot on.

The encoder got a little mechanical friction, but not enough to not move with small winds if the vane is properly designed.

I currently have it display the wind in degrees, and it shows the direction like: N, NE, etc.

Think I have nailed the calibration of north function too.

Would be happy to share the code I have pieced together so far, this is a very cheap way of making an accurate wind vane.

Maybe I will try to replace the IR with a hall effect sensor and a magnet, it may be a better long term solution in harsh conditions?

Hi!

I just finished making a prototype wind vane. I used a rotary encoder (like this: http://www.ebay.com/itm/10pcs-New-High-Quality-Rotary-Encoder-Switch-With-Keyswitch-/310911594094?pt=LH_DefaultDomain_0&…) for detection of position, it's got 18 degrees of resolution.

But since it could occationally miss a step when moved around fast to both sides, I added a IR led and IR receiver that is used to calibrate north against the flat side of the rotary encoders shaft, after adding this it has been spot on.

The encoder got a little mechanical friction, but not enough to not move with small winds if the vane is properly designed.

I currently have it display the wind in degrees, and it shows the direction like: N, NE, etc.

Think I have nailed the calibration of north function too.

Would be happy to share the code I have pieced together so far, this is a very cheap way of making an accurate wind vane.

Maybe I will try to replace the IR with a hall effect sensor and a magnet, it may be a better long term solution in harsh conditions?

.. Or use a sensor by AMS (5048, for instance), or RLS. Those just require one magnet (diametrically magnetized, for sale at supermagnete.de), and you'll get absolute rotation as output

Thank you for the tip! Haven't even read about that kind of sensor, just took what I had laying around.

Maybe i'll try that sensor in combination with a brushless motor or use the bearings and axle from a HDD for my next wind vane, don't really need the extra resolution, but hopefully it's a longer lasting solution.

Gents

Just some information regarding bearings and lubrication.

We were experiencing premature bearing failures in fans and anemometers, despite the installed ones lasting many years.

It was traced to the lubrication, and the newer synthetic oils had a shelf life of 1 year before they separated.

There service life was huge, but shelf life was 1 year, and once the bearings had been lubricated and sitting on the shelf for a year, they were effectively expired.

The solution was replacing them with items less than 3 months old, and the bearing issues went away.

So for your projects using something that's been lying around may not work, and if you can, flush out the old lubricant and replace it.

Mark

Hi just reading an old post on building a wind vane with rotary encoder. I was wondering if you would mind sharing your code. I am currently doing a similar project and would love to see what you came up with. This could certainly give me a jump start on my project.Thanks Seth.