ROOK: Urban Play and Data Visualization

Rook is a playful, non-screen data visualization device designed to disseminate air quality information in North Holland. Built around the Hollandse Luchten (HL) project's network of citizen-deployed sensor kits, the unit retrieves hourly particulate matter (PM2.5) readings through an API and expresses them as colored mist illuminated by RGB light, with colors mapped to the HL maps on a green-yellow-red scale derived from European Union directive 2008/50/EC. The paper positions Rook as a response to the limitations of dashboards and numerical displays, which it argues are often difficult for the public to interpret and tend to be experienced individually. Its central thesis is that ludic, physicalized visualization in public space can raise awareness of environmental issues and enable collective experience, while the interplay between playful interaction and occasionally menacing red tones invites critical reflection.

The document outlines the device's technical specifications, including its dimensions of 54 by 54 by 72 centimeters, its ultrasonic mist generation from clean water, and three buttons that display hourly average, minimum, and maximum PM2.5 levels. It frames three design principles: avoiding screen-based interfaces, enabling playful engagement through the affordances of mist, and avoiding top-down solutions. Rook is described as deployable both indoors, such as at a climate change center, and outdoors at public events. The authors present the work as a contribution to research at the intersection of smart cities, media architecture, and playful design, arguing for bringing the "control room" of urban data into physical public space. The paper is a design-oriented contribution, with its reflections drawn from the literature on citizen sensing, urban gamification, and reflective design rather than from empirical user studies.