IAQLogger

An Indoor Air Quality monitor I built for a client who wanted to display the capabilities of their filters in a fair exposition cabinet.

The device sports an ESP32, a SPS30 particulate matter sensor, an iAQ-Core CO2 and TVOC sensor, and an eInk Display for coolness.

One of the requirements was also to expose both live and histyorical data through an API to drive a WEB frontend (not part of this project).

All code has been released under the GNU General Public License V3, with permission of the client, as it doesn't represent their core business and allowed me to showcase my projects.

Hardware

The assembled contraption, with a generous dose of hot glue to add extra sturdiness during trasportation (I know, I know, it's not production ready). At the bottom you can barely see the large (2500 mAh) battery that ensures at least a full day at the fair with WiFi and all sensors enabled.

The temporary nature of the hand-wiring and hot glueing is hidden in a 3D-Printed enclosure.

API

The /info endpoint returns current live data from the device.

GET 'http://iaqm.local/info'

{
    "ip": "192.168.8.134",
    "disk": {
        "used": "411389",
        "total": "1378241"
    },
    "battery": {
        "level": "73",
        "voltage": "3.88"
    },
    "iaq": {
        "temperature": "26.0",
        "humidity": "58",
        "co2": "-9999",
        "tvoc": "-9999",
        "pm1": "7",
        "pm2p5": "9",
        "pm4": "10",
        "pm10": "10"
    }
}

The /logs/{n-days} endpoint allows to fetch a CSV data log {n-days} in the past

GET 'http://192.168.8.134/log/0'

TIME,T,H,CO2,TVOC,PM1,PM2.5,PM4,PM10
2022-03-15T00:00,22.4,35,3620,998,2,2,2,3,4118
2022-03-15T00:01,22.5,37,3675,1013,4,5,5,5,4132
2022-03-15T00:02,22.7,36,3690,1018,4,5,5,5,4138
...