Lancaster University Researchers Make Exercise an RFID-enabled Game

The Pac-Lan game, deployed at the university in early 2006, has been played on a temporary maze laid out at the campus. To play the game, each Pac-Lan player wears an NFC tag pendant and carries a Nokia phone with a built-in RFID interrogator. The playing field and each of the four players' locations are displayed on the phone's screen, using Pac-Lan game software designed by Mobile Applications. Players collect pills using their phone to tap the brightly colored RFID-enabled discs mounted on posts around the maze. Four other players take the role of the ghosts and attempt to hunt down the Pac-Lan players.

The game is controlled by a computer server running a Java application that links Pac-Lan players and the ghosts. The server relays to the Pac-Lan players their current position, and that of the ghosts, based on the pills collected. Ghosts can use the pills as well, tapping their phones within range of the RFID tags to learn the other Pac-Lan players' last known position, based on the last time they collected a pill. The ghosts can kill a Pac-Lan player by using a mobile phone to tap the player's pendants. Similarly, when a Pac-Lan player collects a power pill, he can then kill the ghosts using the same RFID detection process. Dead ghosts must then return to the central point to be reactivated into the game. Points are allocated based on the number of pills collected and ghosts killed.

The ghosts' RFID tag is attached to the back of their costume.

"The idea was to play a real-world mobile game by mixing reality with cyberspace," Coulton says. "It can help promote exercise with the fun of a video game." Pac-Lan was developed not just to encourage exercise, he notes, but also to explore new innovative ways to use mobile phone technology, which is part of the Mobile Applications Research Group's mission.

Bird contacted Coulton to suggest a similar system that would encourage exercise among Londoners. Bird envisioned using NFC-enabled phones in conjunction with RFID tags such as those embedded in Oyster cards, electronic transit tickets that contain an RFID inlay with a Mifare chip. The goal is to create a system that rewards Transport for London transit passengers for exercising on their way to and from work, or just making their way around the city.

In August 2007, Bird and Coulton sought the use of a Java-based system similar to Pac-Lan; in this case, however, 12 NFC-enabled Nokia phones were installed in sealed containers on posts around London's 350-acre Hyde Park. About 30 volunteers, consisting of park staff and others who were simply interested in the project, used small plastic cards with embedded Mifare RFID tags to simulate the Oyster cards commuters would use in the envisioned program.