21cncstudio/project_aura

Project Aura is an open-source DIY air quality monitoring station designed for makers who want a finished, polished device rather than a bare electronics board. It uses an ESP32-S3 microcontroller, a compact, Wi-Fi-capable chip popular in hobbyist electronics, combined with a touchscreen display and multiple sensors to measure a wide range of air quality metrics. The device measures particulate matter at sizes PM0.5, PM1, PM2.5, PM4, and PM10, temperature, humidity, CO2, VOC (volatile organic compounds, chemicals that evaporate at room temperature), NOx (nitrogen oxides), formaldehyde, and optionally carbon monoxide and other gases. Data is displayed on a touchscreen UI with night mode and customizable themes, and also served through a local web dashboard accessible in your browser, no internet required. It integrates with Home Assistant, a popular open-source home automation platform, via MQTT, a messaging protocol for connected devices, with automatic device discovery. This means readings can appear in your smart home dashboard without manual configuration. There is also an optional analog output for controlling a 0 to 10 volt fan based on air quality thresholds. Assembly requires no soldering, since components connect via standard Grove and QT cables, and the minimum parts list is just the ESP32-S3 board, a Sensirion SEN66 sensor module, and power. The firmware is built with PlatformIO and Arduino-ESP32. A crowdfunding campaign offers 3D-printable enclosure files and detailed build guides, and the device includes safe-boot rollback if a configuration crash occurs. The full README is longer than what was shown.