Air Quality
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The monitoring of air quality has become a more significant activity as the health implications of poor air quality have become more apparent.
This project shows how a low cost sensor, managed by a small Raspberry Pi Zero, can be built using a Nova SDS011 particle concentration sensor.
This type of sensor uses a laser scattering technique to measure particle concentrations in the air from 0.3 through to 10 μg/m3 (see this link for more detail on various techniques for particle size analysis). Data output from the SDS011 sensor provides direct readings of PM2.5 and PM10 (where PM stands for Particulate Matter) that are the two readings most used to assess air quality.
The project demonstrates how a complete sensor assembly can be built housing not only a SDS011 sensor, but also:
- a DHT11 humidity and temperature sensor,
- a DS18B20 temperature sensor,
- a BMP180 pressure and temperature sensor
- a Raspberry PiZero, used to control and manage the system, with
- a 3 USB port + ethernet port adaptor used to expand the Pi's options.
The two images at the top right of the page show the two builds that have been completed and have been installed at indoor and outdoor locations. The image at the top left of the page shows a close up of the SDS011 held in a custom 3D printed framework that is inserted into a (readily available UK domestic plumbing!) PVC tube.
All the custom 3D print designs can be downloaded from the Prusa web site here.
A measurement regime has been implemented, controlled by Python coding on the Raspberry Pi Zero, that collects data every 30 minutes where the temperature, humidity and pressure measurements are single readings but the PM2.5 and PM10 values are averages of 50 readings taken with a short interval between each reading - where the full measurement cycle of all the readings and their storage typically takes about 85 seconds.
The collected data is stored locally on a USB drive as well as being automatically uploaded to a Tiki tracker using the IoT/Tiki API methods discussed in the main IoT web page with further IoT documentation and downloadable software available here.
Further details of this Air Quality Monitoring project are at these links:
IoT projects currently documented:
More about IoT:
All the currently available maker project information: