Design
AQAb is designed as a safety vest using authentic materials and looks of work wear. Three gasses indicating air quality are measured by sensors build into the vest. It uses a soft display to visualise the results. This display is made up of fluorescent fabric covered with a layer of thermochromic ink. If air quality deteriorates a larger portion of the fluorescent fabric is visible. Better air quality results in smaller portions being visible. The shape of the areas that will light up are taken from the molecule shapes of the gasses measured. Three different fabric colours are used for the three gasses. Every two minutes the current air quality is measured resulting in a slow animation of the changes in air quality over time.
The vest has one soft switch: a zipper that can be opened and closed. With this zipper the wearer can inform the system that it smells good (open) or bad (closed.)
The vest has numerous pockets some of which contain: a mobile phone (for sending data to the internet), two battery packs (to power the electronics), a black box (that holds the sensors.)
Air quality
The three gasses that are measured by the AQAb are: Carbon Monoxide, Ozone and Nitrogen Dioxide. The choice for these sensors was bases on national and international regulations, mimicking a part of the measurements as being done by the Dutch government. Choice was also limited by the small availability of different sensors. In addition to the gas sensors, humidity and temperature are measured to provide a context for interpretation.
Awareness
Awareness is promoted in different ways. Obviously the wearer can get an insight into clean and polluted areas just by wearing the vest in different locations and under different conditions. Measurement is automated and conducted every two minutes. As location and air quality data are send to internet and saved in an online database they can be looked up and compared. The zipper button is a useful tool for stimulating awareness in the wearer. Working the zipper triggers measuring. So the wearer can investigate if smell tells her anything about air quality and thus enhance intuition.
Sharing
The online data not just sits in the database but is visualised on
this website. Maps are used to display air quality in different locations. A calendar helps to compare locations at different moments. The structured data can also be shared on other locations on the web like Pachube.
Safety
AQAb plays with the safety vest metaphor. High visibility standards for work wear are strictly regulated. The more reflective material the better the visibility, the higher the safety level. AQAb visualises air quality data by increasing the high visibility area shaped as the gas’ molecules. Here higher visibility means less safety.
The internal workings of the vest consists of two parts. One part takes care of the data, the other of the display.
Five sensors are placed inside (Carbon monoxide, Ozone, Nitrogen Dioxide, humidity) and attached to (temperature) a ventilated box. This box also holds the microcontroller and Bluetooth board. All is powered by six AA size batteries making sure that the power is adapted for the different parts. The software on the Arduino checks the sensors every two minutes and sends a formatted string of values via a Bluetooth connection to the Python program running on the Symbian phone. That program submits the sensor data, user activated data (view below) and the GPS data from the phone to an online database. Through a website front-end visitors can retrieve the logged data and see them in context through the use of Google Maps.
The three displays, one for every gas measured, are constructed using thermochromic ink and rings of isolated resistive wire and are placed at the front of the vest. They display the sensor reading every two minutes. Three D size batteries supply power for the heating of the rings. Four custom made print boards control the driving and powering of the strips. One board contains the shift registers which control the turning on and off of the 24 display elements. The other three amplify the power, one for each display. Low air quality means more rings will light up, high air quality means less or no rings will light up.
The wearer may activate the system by opening or closing a special zipper which functions as a switch. Opening the zipper indicates a good smell to the system, closing the zipper a bad smell. After activation the system automatically runs the cycle of measuring, sending and displaying once.
The whole system can be switched on and off by two switches attached to the battery packs.
Fabrics: cotton polyester mix
Silver reflective strip
Thermostar® thermochromic ink
Resistive wire & silicon tubing
1 custom shift register board
3 custom FET boards
Wires
Metal zipper
Conductive wire
Arduino Pro Mini 328 - 5V/16MHz
BlueSMiRF Gold Bluetooth board
AppliedSensor CO & NO2 sensors
Futurlec MQ131 O3 sensor
3 1,2 Volt, 10 Ampere D-cell batteries (rechargeable)
6 1,2 Volt 2,5 Ampere AA-cell batteries (rechargeable)
Symbian 5 Mobile Phone
The people who played important parts in the realisation of AQAb:
People or organisations who made possible the realisation of AQAb by funding, sponsoring or (free) advice and help:
