I like homebrewing, electronics and programming.
One important aspect of brewing is to control the temperature of the fermentation. The temperature has a huge influence on the taste of the produced beer. It is important that you can keep the temperature very stable. Also there are different phases in the fermentation. For example you want to start the fermentation at 20C, near the end of the main fermentation you might want to go to 22C, followed by a couple of days at 5C.
Many homebrewers have some kind of thermostat to control a cooler and a heater. Most solutions are pretty simple (dutch forum, flemish forum). The most advanced solution I have looked at is Henielms's TControl. I actually bought this solution, and I think it works very well. The main components are an IO-board with some relays, software (Labview based) and a CO2 volume sensor.
The IO-board and Labview do not allow me to make changes. Therefor (and just because it is fun to do) I decided to make my own version. I do plan to keep using the CO2 production sensor as I think it works very well.
I want to use as much as possible 'standard/off the shelf' components and free/open-source stuff.
That is how I ended up looking at the Arduino.
Some early project ideas/requirements were:
- minimal 'hardware' work - use off the shelf components
- use free/open source stuff
- measure temperature
- control 2 relays (one for heating, one for cooling)
- work with Henielma's CO2 sensor.
- follow the status from internet
- control over internet, eventually also using my android phone
- simple GUI
Obviously not everything will be there from the start...
Given the above requirements I ended up looking into the Arduino environment.
The Arduino Yun looked like a very good candidate for this project.
The appealing features of the Yun board for me were:
- microcontroller with enough IO
- Wifi on-board
- Linux on-board with support for easy internet access (curl, temboo, ...)
- relatively cheap (around 60 EUR)
From a hardware point of view, I think I only need the Yun, a temperature sensor, the CO2 sensor, a USB power source, 2 relays (plus maybe some resistors, LEDs, ...)
The rest of this blog will present the progress (hopefully) with this project. I also plan to use the blog for myself as a reference and log-book.