My WindPOV project was featured on Hackaday:
It displays the temperature and humidity on the wing tip by way of persistence of vision.
The idea of using our Contiki enabled 802.15.4 board has been tossed around a bit, this would allow tweets to be sent directly from the windmill via twitter.
The newest version uses the same PCB but with a bigger (NEMA23) stepper motor, a larger wingspan and 5mm straw-hat red LEDs mounted in the blade. The blade angle was reversed to spin counter clockwise and the software counters were inverted to compensate. A pair of blade hangers were CNC milled from HDPE to match the NEMA23 motor.
And here is the video, the cut in speed, which is calculated in software needs to be adjusted a little higher to reduce visible artifacts at low wind speeds. Some artifacting is also present from the video compression and frame rate aliasing. It’s a work in progress…
And here is a picture of the backside, all of the components rotate with the blades including the motor body. The circuit board is attached with wire ties, with a bit of rubber between it and the motor for padding. The PCB has only a few coats of clear acrylic spray to protect it from the elements.