anton

A quick and dirty air sensor which submits data directly to an InfluxDB v1 instance, without auth.

I built this because the west coast is on fire, and I ran out of Luftdaten sensor parts. It's not pretty or full featured but it works.

Requirements

Hardware:

• An ESP development board for ESP8266 or ESP32, such as:
  • NodeMCUv3 or similar ESP8266 platform
  • Lolin32 or similar ESP32 platform
• A particulate sensor, one of:
  • ZH03B
  • PMS7003; Only the PMS7003 has been tested, but other PMSX003 sensors may work.
• (Optional) A multisensor:
  • BME680 sensor and breakout board; configured for i2c
• (Optional) A CO₂ sensor:
  • MH-Z19B

Software:

• InfluxDB v1.8

Wire the ZH03B as follows:

• Pin1: VU
• Pin2: Ground
• ESP8266
  • Pin4: D4
  • Pin5: D3
• ESP32
  • Pin4: TX2 (GPIO17)
  • Pin5: RX2 (GPIO16)

Or the PMS7003 as follows:

• Pin1: VU
• Pin3: Ground
• ESP8266
  • Pin7: D3
  • Pin9: D4
• ESP32
  • Pin7: TX2 (GPIO17)
  • Pin9: RX2 (GPIO16)

(Optional) Wire the BME680 as follows:

• VCC: 3v3
• GND: Ground
• ESP8266
  • SCL: D1
  • SDA: D2
• ESP32
  • SCL: SCL (GPIO22)
  • SDA: SDA (GPIO21)

(Optional) Wire the MH-Z19B as follows, tested only on ESP32:

• VCC: VU
• GND: Ground
• ESP8266
  • TXD: D5
  • RXD: D6
• ESP32:
  • TXD: GPIO18
  • RXD: GPIO19

A 3D printable case for Anton is available at PrusaPrinters. Note: the case fits the ZH03B and ESP8266; for PMS7003 or ESP32, you're on your own right now, but I'll make one in the future.

Installation

This is built using PlatformIO; refer to their docs on building/uploading.

Setup

Once uploaded and booted, a wireless network called anton will be created; join this network and you will be directed to a captive portal for configuration.

Measurements

Measurements are submitted to the configured database as a measurement named particulate_matter. It will contain the following tags:

• node the sensor name
• location (optional) the sensor location

…and the following fields containing integer values:

• p1_0 PM1.0
• p2_5 PM2.5
• p10_0 PM10
• aqi EPA AQI

…and the following string values:

• aqi_contributor the primary AQI contributor (highest value); the string will match the measurement name, e.g. p2_5

Note: currently only PM10 and PM2.5 are accounted for in AQI measurements, following the EPA standard.

Note: if the AQI cannot be determined, either due to overflow or other error, it will be omitted from the InfluxDB submission.

Multisensor

If you have the optional multisensor connected, the following additional fields fields will be sent; all are integers unless noted:

• temperature_c (float) °C
• temperature_c_raw (float) °C, uncompensated
• humidity %rh
• pressure hPa
• gas_resistance Ohm
• iaq EPA IAQ.
• iaq_accuracy IAQ accuracy; see notes
• co2_equiv Equivalent CO₂ PPM
• co2_equiv_accuracy Equivalent CO₂ accuracy; see notes
• breath_voc (float) Breath VOC
• breath_voc_accuracy Breath VOC Accuracy; see notes

Note: Various accuracy values are provided by the Bosch Sensortec BSEC library, which have the following meaning (source):

• 0 sensor is stabilizing
• 1 readings were too stable to define references
• 2 currently calibrating
• 3 calibrated

Dedicated CO₂ Sensor

If you have the optional dedicated CO₂ sensor connected, the following additional integer fields will be sent:

• co2 PPM

Note: when using the optional dedicated CO₂ sensor, you must provide a base calibration every few weeks. This can be done from the dashboard's calibration page, and should be initiated when background levels are low. If indoors it's recommended to open a window and allow good air circulation for several minute before performing the calibration. This calibration takes 20 minutes.

Administration

Once configured, a webserver is exposed on port 80 which can be used to view sensor values, update firmware, change configuration, and reboot or reset the sensor.

Changelog

See CHANGELOG.

Acknowledgements

This was quick to implement due to the following excellent libraries:

• @ShaggyDog18/SD_ZH03B
• @tobiasschuerg/InfluxDB-Client-for-Arduino
• @prampec/IotWebConf
• @BoschSensortec/BSEC-Arduino-library
• @fu-hsi/PMS
• @Erriez/ErriezMHZ19B

License

The code contained in this repo is released under the GNU GPL-3.0.

Building this project requires pulling in the various submodules under the lib directory, each of which has their own license; of note the BSEC library provided by Bosch Sensortec has a closed source binary blob provided under a unique license which you must abide to use this software.