How to use ESP8266 to design a portable air quality monitoring station

This time I will introduce a portable air quality monitoring station based on ESP8266 - AiryFi.

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Air is what we breathe. It's about 78% nitrogen, 21% oxygen, and 1% argon, along with various "other" bits and pieces, many of which have been filtered by humans and their associated respiratory organs. While carbon dioxide is an obvious pollutant that contributes to climate change, there are other factors to consider when it comes to human health, such as particulate matter. This is just very tiny particles like soot and smoke. They are divided into two categories based on particle size: those less than 2.5 microns in diameter (PM2.5) and those with a width between 10 and 2.5 microns (PM10). Respiratory disease, heart disease and lung cancer have all been linked to this pollution.

Obviously this is vital information and while most major cities have official sensors, the impact is likely to be very localized near busy routes and localized to valleys.

AiryFi is an air quality monitoring station based on ESP8266, with built-in PMSA003 laser dust sensor and BME280 humidity sensor. AiryFi is an open source portable air quality monitoring station that measures the quantity and mass of suspended particulate matter (PM1.0, PM2.5 and PM10) per unit volume in the air.

AiryFi allows you to collect detailed information about the quality and quantity of suspended particles in the air, as well as humidity sensors that measure relative humidity, air pressure, and ambient temperature. You can also share data to the cloud using the onboard ESP8266, which comes pre-programmed with AT command set firmware, allowing you to connect it to your Arduino device using C++, and you can see the output on the onboard 1.14" TFT display.

The AiryFi board also has a battery connector for direct connection to a battery that acts as a UPS, as well as optional debug pins and some onboard switches for power on/off, flash and reset, making the AiryFi a great Other features of the product.

Construct

PMSA003-Digital Laser Dust Sensor: A Brief Overview

PMSA003 (PlantowerPMSA003PM2.5 laser dust sensor) is a digital universal particle concentration sensor that can be used to calculate the mass and quantity of suspended particles in the air per unit volume and output it in digital format. To provide fast and accurate concentration data, sensors can be placed in the air of suspended particulate matter over a range of environmentally relevant concentration ranges.

What is the function of PlanpowerPMSA003PM2.5 laser dust sensor?

The concept of laser scattering is used in the PMSA003 sensor. Specifically, laser irradiation scatters in airborne particles while collecting scattered light at a certain angle to produce a curve of scattering intensity versus time. The particle equivalent particle diameter and unit volume of particles of different particle sizes are calculated by the microprocessor using the MIE theory of this method.

PMSA003 technical details

BME280 Brief Overview

Relative humidity, air pressure and ambient temperature are measured by the BME280 humidity sensor

The BME280 is a humidity sensor designed for mobile and wearable applications where small size and low battery consumption are important design criteria. The device combines excellent linearity with a high-precision sensor and is ideal for low current consumption, long-term stability and EMC resiliency. The humidity sensor's very fast response time allows it to meet performance standards for new applications, including environmental sensing and excellent accuracy over a wide temperature range.

BME280 technical data

ESP8266WiFi module

Low-power, highly integrated Wi-Fi solutions from Espressif. The ESP8266 WiFi module is a standalone SOC with a built-in TCP/IP protocol stack that can provide any microcontroller with access to WiFi networks. The ESP8266 can run applications or offload all Wi-Fi network activity to another CPU. Each ESP8266 module comes pre-programmed with AT command set firmware.