Fan POV

[allank]

Hi,
I'm experimenting with mounting the spoke POV board to a pedestal fan. Like this one:
http://dev.spirit.co.za/NuWorld/Uploade ... e%2005.jpg
I've taken off the fan blades and replaced it with some wood to mount the boards to. I've also removed the protective cage.

I have it working great except for the position of the sensor/magnet and their interaction. I've been mounting the magnet to the pole (near the buttons) so that it aligns with the bottom side of the fan circumference, but, as there is a little vibration from the swivel part of the fan, the magnet keeps falling out of sync.

My solution is to mount the magnet so that it protrudes from the top of the fan motor, but to do this the sensor will need to be moved about half-way down the board. This is fine to re-wire, but (here is my problem) it will give false information regarding the speed it's spinning. The sensor will tell the chip that it is spinning faster than it actually is - because the circumference is now about half the size.

So.... is there a way of re programing the chip to calibrate it to the new sensor position?

Any help would be greatly appreciated!

Thanks,
A.

[adafruit]

the micro it doesnt calculate linear speed, it calculates rotational speed. otherwise, how would it work on BMX bikes as well as road bikes?

[jennyfan]

Try to look for some aluminum fan blade for the unit to make it better. Wood is not hard enough to support the power of the fan motor. It would easily broke down and also are you going to use the same cover which is like "net" for your fan? I think safety wise they are advisable especially if there are kids around but in proper circulation of air, I don't think they are good.