In 2019 I experimented with greens at times. One day I came across an article describing how certain bacteria break down unpleasant chlorophyll when the product is kept at a certain humidity level. In order to maintain humidity but not allow the goods to mold, it is important to ventilate several times a day. At this point my automation drive kicked in and I had to build a little automat.

❮ ❯

It ended up being a big canning jar with a servo to open the only overlying lid on defined times. Through a glass hole a dht22 is connected to control humidity. The control is done by an Arduino Nano, which is housed in a TikTak box. The running program can be controlled via a menu on an OLED screen with a joystick. I liked the integration in the box.

The menu can be used to open and close the glass manually. The main function is the automatic mode with a certain number of openings per day and defined opening time. In addition, there is a moisture protection. If a limit value is reached, the glass opens additionally. The menu fields can be easily controlled via left-right movements. Individual options are always selected via top-bottom movements. The control is without delays.

To exchange more air when opening the jar, a paper fan is placed on the underside of the lid. In addition, the lid moves back and forth quickly several times when opening and closing. The fit to attach the servo well to the glass is cast with a glue gun.

For the realization of the menu I used the U8g2 library. It was my first programming project, so the code is quite cumbersome. That is the only reason why I did not share it here. Also dont judge my soldering solutions from back then. ;)

The system was in use for some months and did great.