fermentord

Control the temperature of your fermentation process.

TODO

• Cooler should not have min runtime, but run till min. temp cool level
  • E.g. cool until setpoint - 1 degrees is reached
  • ...or just make the damned PID work

Epics

Heater/Cooler

Persona	Description
Brewer	The person responsible for the wort and the fermentation process
Operator	The person responsible for the fermentation tank and the system controlling it

As a brewer I need to maintain the wort at a specific temperature so that my fermentation process is predictable As an operator I need an alert if the system can't maintain the temperature, so that I may correct the problem

Ambient temperature

• Ambient temperature
• Case temperature
• Wort temperature
• Wort gravity

User stories

Acceptance criteria

• Given the wort is at or above the requested temperature and the heater is running then stop the heater

• Given the wort is above the requested temperature and the heater is not running then start the cooler

• Given the wort is above the requested temperature

• Given the wort is too cold and the cooler is running then stop the cooler

• Given the wort is too cold and the cooler is not running then start the heater

• Given the cooler is running

• Given the cooler is running when then the heater may not start

• Given the heater is running then the cooler may not start

• Given the temperature is

Data logging

• Ambient temperature

• Case temperature

• Wort temperature

• Wort gravity

• Data is stored in sqlite3

• Data is scraped and stored in PostgreSQL

• Data is removed from sqlite3 when confirmed in PostgreSQL

Metrics

Prometheus metrics

• Ambient temperature
• Chamber temperature
• Wort temperature
• Wort gravity
• Heater state
• Cooler state
• Tank pressure

Drivers

On the Raspberry Pi you'll need to add dtoverlay=w1-gpio (for regular connection) or dtoverlay=w1-gpio,pullup="y" (for parasitic connection) to your /boot/config.txt. The default data pin is GPIO4, but that can be changed from 4 to x with dtoverlay=w1-gpio,gpiopin=x.

echo dtoverlay=w1-gpio,gpiopin=4,pullup=0 >> /boot/config.txt

modprobe wire
modprobe w1-gpio
modprobe w1-therm

Build

A Raspberry Pi 1 is used, so we compile for ARMv6.

cd cmd/fermentord
GOARCH=arm GOARM=6 GOOS=linux go build