Anr air quality sensor mounted on a bike's handlebar

Measuring Air Quality Using Mobile Sensors For The Masses

December 13, 2021 by Robin Kearey 8 Comments

Poor air quality is a major problem for city dwellers the world over. Dust, smoke, particles and noxious gases from vehicles, industry and agriculture makes many megacities downright hazardous to live in. Pinpointing the source of pollution and developing strategies for mitigation requires accurate data on pollutant levels, but obtaining these numbers is not always easy.

Enter CanAirIO, a citizen science project that aims to gather air quality data from around the world by putting sensors into the hands of as many people as possible. Its team has developed two different sensor nodes for this purpose: an indoor one that can measure CO₂, and a mobile one that can measure particulate matter (PM) levels. Both versions are powered by an ESP32 microcontroller that reads out the air quality sensors and connects to the Internet using WiFi or BlueTooth. The data can then be shared online to create detailed maps showing local variations in air quality.

The design of the sensor nodes is fully open-source, allowing anyone with basic electronic skills to build them. The sensors are a Sensirion SCD30 for CO₂ measurement and an SPS30 for PM levels. The mobile version comes with a neat 3D-printed enclosure that can be mounted on a bike’s handlebar, enabling the user to quickly gather data around their neighbourhood. A mobile app simplifies setting up the sensors and sharing the data.

The project has already been successful in gathering detailed data in the city of Bogotá, Colombia, and will no doubt prove useful in many other pollution hotspots around the world. We’ve seen similar community efforts to monitor air pollution and even radiation in various places, both showing how relatively simple devices can help to make a difference in people’s wellbeing. Continue reading “Measuring Air Quality Using Mobile Sensors For The Masses” →

Prepare For Wildfire Season With An Air Quality Monitor

November 4, 2021 by Bryan Cockfield 12 Comments

For some reason, wildfire seasons in Australia, North America, and other places around the world seem to happen more and more frequently and with greater and greater fervor. Living in these areas requires special precautions, even for those who live far away from the fires. If you’re not sure if the wildfires are impacting your area or not, one of the tools you can build on your own is an air quality meter like [Costas Vav] shows us in this latest build.

The air quality indicator is based around an Adafruit Feather RP2040 which is in turn based on the 32-bit Cortex M0+ dual core processor. This makes for a quite capable processor in a small package, and helps accomplish one of the design goals of a rapid startup time. Another design goal was to use off-the-shelf components so that anyone could easily build one for themselves, so while the Feather is easily obtained the PMS5003 PM2.5 air quality sensor needed to be as well. From there, all of the components are wrapped up in an easily-printed enclosure and given a small (and also readily-available) OLED screen.

[Costas Vav] has made all of the files needed to build one of these available, from the bill of materials to the software running on the Pi-compatible board to the case designs. It’s a valuable piece of technology to have around even if you don’t live in fire-prone areas. Not only can wildfire smoke travel across entire continents but simple household activities such as cooking (especially with natural gas or propane) can decimate indoor air quality. You can see that for yourself with an army of ESP32-based air quality sensors.

Compact Sensor Keeps You Safe By Watching CO2 Levels

August 24, 2021 by Dan Maloney 21 Comments

Remember when work meetings were just a bunch of people filling up a small, poorly ventilated room with their exhaled breath? Back in the good old days, all you had to worry about was being lulled to sleep by a combination of the endless slide deck and the accumulation of carbon dioxide. Now? Well, the stakes may just be a little bit higher.

In either situation, knowing the CO₂ level in a room could be a handy data point, which is where a portable CO₂ sensor like this one could be useful. Or at least that’s [KaRMaN]’s justification for SYPHCOM, the “simple yet powerful handheld carbon dioxide meter.” The guts of the sensor are pretty much what you’d expect — an Arduino Pro Micro, a SenseAir S8 CO₂ sensor board, and the necessary battery and charging circuits. But the build does break the mold in a couple of interesting places. One is in the choice of display — a 1980s-era LED matrix display. The HDSP2000 looks like it belongs in a nice bench meter, and is surprisingly legible without a filter. It looks like it flickers a bit in the video below, but chances are that’s just a camera artifact.

The other nice part of this build is the obvious care [KaRMaN] put into making it as small as possible. The layout of boards and components is very clever, making this a solid, compact package, even without an enclosure. We’ve seen CO₂ sensors with more features, but for a quick check on air quality, SYPHCOM looks like a great tool.

Continue reading “Compact Sensor Keeps You Safe By Watching CO2 Levels” →

Hacked IKEA Air Quality Sensor Gets Custom PCB

August 13, 2021 by Tom Nardi 19 Comments

Last month we brought word of the IKEA VINDRIKTNING, a $12 USD air quality sensor that could easily be upgraded to log data over the network with the addition of an ESP8266. It only took a couple of wires soldered to the original PCB, and since there was so much free space inside the enclosure, you didn’t even have to worry about fitting the parasitic microcontroller; just tape it to the inside of the case and button it back up.

Now we’ve got nothing against the quick and dirty method around these parts, but if you’re looking for a slightly more tidy VINDRIKTNING modification, then check out this custom PCB designed by [lond]. This ESP-12F board features a AP2202 voltage regulator, Molex PicoBlade connectors, and a clever design that lets it slip right into a free area inside the sensor’s case. The project description says the finished product looks like it was installed from the factory, and we’re inclined to agree.

Nothing has changed on the software side, in fact, the ESP-12F gets flashed with the same firmware [Sören Beye] wrote for the Wemos D1 Mini used in his original modification. That said [lond] designed the circuit so the MCU can be easily reprogrammed with an FTDI cable, so just because you’re leaving the development board behind doesn’t mean you can’t continue to experiment with different firmware builds.

It’s always gratifying to see this kind of community development, whether or not it was intentionally organized. [lond] saw an interesting idea, found a way to improve its execution, and released the result out into the wild for others to benefit from. It wouldn’t be much of a stretch to say that this is exactly the kind of thing Hackaday is here to promote and facilitate, so if you ever find yourself inspired to take on a project by something you saw on these pages, be sure to drop us a line.

ESP8266 Adds WiFi Logging To IKEA’s Air Quality Sensor

July 24, 2021 by Tom Nardi 38 Comments

Introduced back in June, the IKEA VINDRIKTNING is a $12 USD sensor that uses colored LEDs to indicate the relative air quality in your home depending on how many particles it sucks up. Looking to improve on this simplistic interface, [Sören Beye] tacked an ESP8266 to the board so it can broadcast sensor readings out over MQTT.

Just three wires link the ESP8266 to the PCB.

While some of us would have been tempted to gut the VINDRIKTNING and attach its particle sensor directly to the ESP8266, the approach [Sören] has used is actually quite elegant. Rather than replacing IKEA’s electronics, the microcontroller is simply listening in on the UART communications between the sensor and the original controller. This not only preserves the stock functionality of the VINDRIKTNING, but simplifies the code as the ESP doesn’t need to do nearly as much.

All you need to do if you want to perform this modification is solder a couple wires to convenient test pads on the VINDRIKTNING board, then flash the firmware (or write your own version), and you’re good to go. There’s plenty of room inside the case for the ESP8266, though you may want to tape it down so it doesn’t impact air flow.

While not required, [Sören] also recommends making a small modification to the VINDRIKTNING which makes it a bit quieter. Apparently the 5 V fan inside the sensor is occasionally revved up by the original controller, rather than kept at a continuous level that you can mentally tune out. But by attaching the sensor’s fan to the ESP8266’s 3.3 V pin, it will run continuously at a lower speed.

We’ve seen custom firmware for IKEA products before, but this approach, which keeps the device’s functionality intact regardless of what’s been flashed to the secondary microcontroller, is particularly appealing for those of us who can’t seem to keep the gremlins out of our code.

[Thanks to nexgensri for the tip.]

Lamp Sheds Light On Air Quality

June 3, 2021 by Kristina Panos 4 Comments

It can be difficult to appreciate when the air quality is decent and when it’s poor, unless conditions are so bad that you can literally see the smog hanging in the air. Rather than try to digest a bunch of air quality numbers, [guillaume_slizewicz] built Canari — a lovely lamp that sheds light on the air pollution problem by taking local air quality data and turning it into light patterns.

Canari is of course named after the brave birds that once alerted miners to dangerous air conditions before they were forced to switch to carbon monoxide sensors. This bird has a Raspberry Pi Zero W that gets air quality data from a public API and controls the lights with a PWM bonnet based on the concentration of particulates in the air. The more particulates, the dimmer the LEDs are, and the faster they fade in and out.

The main piece of data that Canari grabs is the amount of particulate matter, and the display can switch between representing the level of PM2.5 (particulate matter with diameter less than 2.5 micrometers) in the air and PM10. Check out the demo and setup video after the break.

More of a numbers person? All you really need is a microcontroller, an air quality sensor, and a display.

Continue reading “Lamp Sheds Light On Air Quality” →

Ooohhh, That Smell: Arduino Monitors Air Quality

April 23, 2021 by Al Williams 26 Comments

According to [Dr. Tom Lehrer’s] song Pollution, “Wear a gas mask and a veil. Then you can breathe, long as you don’t inhale!” While the air quality in most of the world hasn’t gotten that bad, there is a lot of concern about long-term exposure to particulates in the air causing health problems. [Ashish Choudhary] married an Arduino with a display and a pollution sensor to give readings of the PM2.5 and PM10 levels in the air.

The sensor uses a laser diode and a photodiode to detect and count particles, while a fan moves air through the system. If you aren’t up on pollution metrics, PM2.5 is a count of very fine particles (under 2.5 microns) and PM10 is a count of particles for 10 microns. You can find a datasheet for the device online.

Continue reading “Ooohhh, That Smell: Arduino Monitors Air Quality” →