Wind Sensors

[seandepagnier]

Hi abarrow,


It uses the Peet Bros principle, a rotating magnet, metal shield and two hall sensors. The plastic parts can be 3d printed.
He uses a ESP8266 for the processing and wlan to send the wind data to OP. I have got one of his prototypes for just
25 EUR.

I think the rotating magnet with shield concept is ok if you don't care about high resolution of wind direction. It is probably ok for a weather station to get 8 or 16 directions, but I am not sure it is good for making boat polars or steering autopilot to wind. Can anyone comment on this?

I'm not sure about a standard wireless link for wind data. wifi protocol can have significant lag, and this will affect the control loop in an autopilot. It's really impossible to control since it is in the linux kernel, and your VNC packets may slow down the weather measurement. It will work with degraded performance I imagine people will do it.

Otherwise, wired or some other type of wireless transmitter, or maybe even if you have a dedicated wifi receiver (ESP8266) just for the wind sensors it would be better.

One very clever idea is to reuse the existing cable for the anchor light. The white led will not light below seven volts.
If you put six volts to the anchor light it powers the wind sensor with 6-12V -> 3.3V regulator placed inside the anchor light 
housing. If you enable the anchor light the leds get 12 V and start lighting. The wind sensor keeps running.

Very nice idea.

I have built a windvane around four years ago. It uses a BLE112 bluetooth module from Bluegiga. I have connected a
four quadrant magnetic sensor that measures the angular position of a diametral magnet. The angle is sent via BLE

four quadrant? How accurate is wind direction in degrees?

For sailing and polars, we want resolution of 1-2 degrees although 0.5 or better is desired. The davis anemometer with potentiometer vane gives 0.1 degree resolution, but there is a 7 degree deadband which I adjust to face forward (since boat cannot sail directly into wind)