I wanted to create a simple, networked system that I could customize as needed to monitor environmental factors for enclosed environments (terrariums, grow chambers, etc.). Essentially, I wanted a custom IoT solution I could understand at a low level and manage myself without abstraction layers (Alexa Skills, Automation Hubs, and the like). It should be able to save info to a server for further analysis. Secondarily, it should be able to react to changes in the environment and correct them.

This is meant to be used in a client/server system with remote sensor/control hardware. See:

• https://github.com/LinkedMink/environ-manager-hw-rpi
• https://github.com/LinkedMink/environ-manager-server
• https://github.com/LinkedMink/environ-manager-client

Disclaimer: This project was mainly intended as a learning aid and for private use.

Install packages not included in Raspbian.

pip3 install --upgrade pip setuptools wheel  
pip3 install psycopg2 # (or any DB engine compatible with SQL alchemy)  
pip3 install pyodbc   # (or any DB engine compatible with SQL alchemy)  
pip3 install sqlalchemy  
pip3 install Adafruit_Python_DHT  

ConnectionString: https://docs.sqlalchemy.org/en/13/core/engines.html

You can leave the value empty then nothing will be logged. This project has been tested on SQL Server. The latest version of PostgreSql caused problems with the .NET server application.

HttpHost: The host name of this device

This should match the seed value that's inserted within the .NET application. It's used to uniquely identity a hardware device.

This can be ran alone without the API server. You can create the database schema:

python3 create_schema.py  

However, it's probably best to create the entire schema for the API server.

See: https://github.com/LinkedMink/environ-manager-server

See the schematic. It's pretty general, and the components can be swapped out as needed.

• Raspberry Pi
• DHT22
• 1 x 10k Resistor
• 1 x 1k Resitor
• 1 x NPN Transistor
• 1 x LED
• Control Hardware (As needed)
  • 4 x 1k Resitor
  • 3 x NPN Power Transistors
  • Lighting LEDs
  • Humidifier Element
  • Heating Element
  • Power Supply

python3 environ_manager.py  

If everything is working correctly, you can have the process start on boot.

sudo vi /etc/systemd/system/environ-manager.service  

Point the service to the python script.

[Unit]
Description=Environ Manager
After=multi-user.target

[Service]
Type=simple
ExecStart=/usr/bin/python3 /path/to/source/environ_manager.py
StandardInput=tty-force

[Install]
WantedBy=multi-user.target

Enable the server.

sudo systemctl daemon-reload  
sudo systemctl enable environ-manager.service  
sudo systemctl start environ-manager.service  

Check that it started correctly.

sudo systemctl status environ-manager.service