Interactive Physical Map Displays Regional Air Quality

Air quality is a serious issue in many areas. For example, Cairo (a city notorious for poor air quality) has an estimated 12,600 premature deaths per year that are attributable to pollution in the air. But reading a statistic like that is not as effective as a visualization of the danger; humans respond better to what they can see than to what they are told. To harness that for the good of his city, Ahmed Oyenuga created the Interactive Air Quality Map.

This project contains two major parts: the data collection system and the display map. The map contains LED edge-lit clear acrylic cutouts of different regions in the area around Lagos, Nigeria. When a user touches a region, it illuminates in a color that corresponds to the current air quality. Light yellow means that the air quality is good, while red indicates that the current air quality is so bad that it is dangerous. Several levels along a gradient between those two colors provide an approximate measure of the real-time air quality.

For this map to be effective, it needs up-to-date air quality data. While the AQI (Air Quality Index) for Lagos as a whole is available online, the information isn’t granular enough to show how air quality varies throughout the city (like the online maps we have for much of the United States). That forced Oyenuga to gather his own data. To do that, he developed air quality sensor stations using DesignSpark’s Environmental Sensor Development Kit. Each station detects the air quality and uploads the data, along with its GPS location, to the cloud. Oyenuga’s resources are limited and he hasn’t been able to deploy many of these stations, but he did prove the concept.

The interactive map pulls that data from the cloud using an Arduino MKR WiFi 1010 development board. When the user selects a region on the map, the Arduino sets WS2812B individually addressable RGB LED strips around that region to the proper color. A custom board that Oyenuga built on a Microchip ATSAMD21J17 microcontroller handles the capacitive touch sensing and tells the Arduino which region to illuminate.

This project serves two purposes. First, it provides a visualization that hammers home the severity of the air quality in Lagos and that could motivate change. Second, individuals could use the map to plan their trips through the city. If a particular region has especially poor air quality on that day, then they can avoid that area and take an alternate route.