March 2018 – July 2019
It all began with my neighbor giving me his old Playstation 3 that he raised from the infamous YLOD death several times until it finally breathed its last breath. Interested in the unexpected treasures I might find in such a legendary game console, I began disassembling it. Besides a strong 12 V power supply that I could modify for my dad in order to use it for a 12 V air pump, I have salvaged a huge radial fan.
In that time I was living in an apartment the second floor and the summer was ahead of us. So I thought I could build a cooling fan for hot summer nights that could be controlled via an Android App.
I began by constructing the spiral cover for the radial fan, so that the air is drawn in from the bottom and only leaving the cover at its destined outlet. Within the stand a 12 V power supply and an ESP32 micro controller are doing their best to control the fan’s output power.
I couldn’t find something extravagant enough to suit as a base. One Sunday afternoon I was going for a walk in the beautiful forest nearby. I thought, maybe my heavenly father has a good idea what material to choose from. While continuing spending further time with him and taking a look besides the path every here and then, I caught a glimpse of an overturned tree, carrying a tinder fungus. Happily about this idea I would never have thought of on my own, I took the fungus and let it stay for several days in the freezer, so that every insect and parasite would be turned silent.
The tinder fungus was used as a fire starter in the old days – hence the name (have a look at https://en.wikipedia.org/wiki/Fomes_fomentarius). The softer part surrounded by the hard peel is very easy to cut or saw. I inserted a standard power jack and added some 3d-printed feet for a less wobbly stand.
The ESP32 is a much more capable micro controller than e.g. a common Arduino Uno, supporting Wifi, Bluetooth, a bunch of PWM-pins, touch-pins and many more features for just a few bucks. The German diy- and how-to-magazine c’t MAKE: published an article about how to write an Android App by using the Processing API (a slightly different one can be found here https://www.heise.de/make/artikel/Processing-fuer-die-Android-App-Entwicklung-nutzen-4117340.html). I modified their example to fit my needs and letting me control the fan’s blowing strength, direction and tilt angle with a finger tip.
Alongside the app, the ESP32 acts as a web server and the fan’s status can be inspected on the website accessible via the IP address of the ESP32.
Further more, touch buttons on the outside are serving as the primary user interface. The left and right are serving to pan the fan, while the airflow’s power can be reduced or increased via the upper and lower touch buttons. Finally, the button in the center is working as an on-off-knob.
To be honest, since then I didn’t use the fan very often. It is quiet enough when having a stronger blow. And unfortunately I expected sawdust underneath the stand, indicating animals still or again living within the tinder fungus (I cannot explain how).
But I have learned a lot during the process of making it: Besides improving my skills in working with Autodesk Fusion 360, I learned how to program an ESP32 and having it to serve as a web server, even displaying more complex canvasses. It was a good project to catch a glimpse of programming Android Apps with Processing and doing a basic electronic circuit.
Tinder Fungus Fan
March 2018 – July 2019