Trival endevour, though fun and easy to do.
Text and diagram taken from zip file attached.
Orange Pi Zero fan self adapting to temperature, inside Shenzhen Xunlong Software CO.,Limited manufacturered low profile (non-expansion board version) case.
Probably can be used with other SBC's. FanDaemon source provided.
Comes with no warranty of any sort. Use at your own risk.
The software included works with Mainline Kernel 4.13 Armbian image.