skyward-flora

Prototype for a solution to read and transfer data between plant sensors and the cloud.

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Description

Embedded firmware

The sensor-iiot directory is a PlatformIO project, containing the Arduino-based firmware which:

• Reads from a temperature-humidity sensor and a soil moisture sensor then send the data to Azure IoT Hub.
• Controls a relay using Cloud-to-Device (C2D) messages sent from Azure IoT Hub.

The project was tested on a system with the following components:

• NodeMCU-32S ESP32 WiFi+Bluetooth Development Board
• DHT11 sensor
• Sen0193 capacitive soil moisture sensor
• SRD-05VDC-SL-C relay

Web application

The web-app directory is a FastAPI application that reads messages sent to the IoT Hub and displays them onto a web dashboard.

User Manual

• Clone the repository:

git clone https://github.com/emberfox205/skyward-flora.git

Azure IoT Hub

• Follow the guide over IoT for Beginners course to setup Azure IoT Hub up to the point of retrieving the Connection String.

PlatformIO

• Follow official documentation to install and use PlatformIO IDE for VSCode.
• Settings for peripherals' GPIOs, (soil moisture) calibration values, relay control messages and some other global constants are found in platformio.ini.
• Set up credentials by duplicating iotconfigs.h.dist and remove the extension .dist. Follow the instructions within the file.

Note

The codes assume you use SAS Token as the authenticaton method. Value "Device Key" is found on Azure Portal by accessing your IoT Hub (Exact name differs) -> Device Management -> Devices -> Your Device (Exact name differs) -> Primary Key

Hardware assembly

• Make sure the microcontroller is connected to 2.4 GHz WiFi. For Windows laptops and mobile devices, you can enable Mobile Hotspot, adjust the Network band, and connect your ESP to there.

Web Dashboard

• Install miniconda or use your preferred virtual environment option.
• (For miniconda) Create and activate a virtual environment:

conda create --name plant-to-cloud python=3.10.0

conda activate plant-to-cloud

• Install dependencies:

pip install -r requirements.txt

• Move into web-app directory if you haven't already:

cd web-app

• Within the web-app directory, create a .env file:

code .env

• Structure it as below, with the values after the equal sign replaced by your own:

IotHubConnectionString=your-connection-string
EventHubConsumerGroup=your-consumer-group

Note

To get your Consumer Group, access Azure Portal -> Your IoT Hub (Exact name differs) -> Hub settings -> Built-in endpoints -> Consumer Group. You should create a new consumer group and use it for the web app.

• Start a local server:

uvicorn main:app --host 0.0.0.0 --port 8000 --reload

• Now you should be able to access the localhost dashboard in your browser at http://127.0.0.1:8000

• (For miniconda) After usage, deactivate the virtual environment:

conda deactivate

Azure Web App (optional)

• Follow this video to set up Azure Web Services with a free plan. Note that the tutorial does not use Github Actions.
• Also watch this video to setup CI/CD with Azure and Github Actions. Note that you must replace the workflow .yml file created by Azure with this repo's own, as there are differences.

Credits

• azure-sdk-C-arduino
• azure-sdk-for-python
• web-apps-node-iot-hub-data-visualization