Beer fermentation bubble counter: Heltec ESP32 Node-Red Thingsboard

Finally I got it to work! So great. Since i do not have internet access in the cellar and I wanted to count the bubbles created by my fermenting beer in order to know when its finished, I thought why not use the Things Network.
The setup is an heltec node with lmic sending to ttn. from there an http integration to my raspberry with node-red and from there an mqtt request to the Thingsboard running on the same device.

Really great stuff…
Here the prototype Sensor on the air-lock of the fermenter

and the dashboard in TB
The beer just started to produce carbon dioxid!!!


What kind of sensor did you use?

For measuring the temperature I used a
and in order to count the bubbles the following

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Hello Trononimon,
very cool projekt.
Is it possible to get the code for my beer brewing ?

It would be really interesting if you could explain how that works.

My initial guess would be you shine a light at 90 degrees to the sensor and look for reflection off the bubbles, but curious what you actually found workable.

Hello divemax yes sure hier it is. I just updated my old sensor to work with a T-Beam Lilygo. I guess the code is a bit messy, I was experimenting a lot and it is my first TTN Project, but it works. It is not optimized for power consumption or other resources, as it is always plugged in. Any improvements are welcome.
Arduino code to count bubbles and measuring temperature during beer fermentation

Here some images and a short video

I also added a Grafana Dashboard
Grafana Dashboard

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Hello cslorabox
I just attach the sensor (photocell) to the airlock. As soon as a bubble passes by the sensor the output changes. The change triggers an interrupt and increments an integer.

counting bubbles video