Sensor box v1

Objective

Create a system capable of collecting environmental data and sending it to an MQTT broker by connecting to WiFi.

Data to collect

• temperature (AHT20)
• humidity (AHT20)
• air quality (PMS7003, SGP30)
• atmospheric pressure (BMP180)

Power supply

• 3.3V lithium battery
• solar panel

Operation

Every 60 seconds, the system wakes up from a sleep state, checks the WiFi connection, collects and sends data to the MQTT broker. During the interval of time between one transmission and the next, the system goes into a sleep state to consume as little energy as possible.

Topics MQTT

• box01/temperature (float, °C)
• box01/humidity (int, %)
• box01/pressure (int, Pa)
• box01/caqi (int)
• box01/pm01 (int, ug/m3)
• box01/pm25 (int, ug/m3)
• box01/pm100 (int, ug/m3)
• box01/eco2 (int, ppm)
• box01/tvoc (int, ppb)
• box01/h2 (int, ppm)
• box01/ethanol (int, ppm)

Circuit Diagram

Hardware used

• Raspberry Pi Pico W (RP2040) or ESP32
• AHT20
• BMP180
• PMS7003
• SGP30
• Step-up converter 3.3 V - 5 V
• Solar panel
• CN3065
• 3.3V lithium battery

License

MIT License

Authors

• John Toniutti

Notes

• Currently, the DORMANT state isn't used because it doesn't work correctly.