ETH Life - wissen was laeuft
ETH Life - wissen was laeuftETH Life - wissen was laeuftETH LifeDie taegliche Web-Zeitung der ETHETH Life - wissen was laeuft
ETH Life - wissen was laeuftETH Life - wissen was laeuft

Rubrik: Science Life

High-tech game for Regensburg
The world as a mobile phone game

Published: 13.07.2006 06:00
Modified: 12.07.2006 21:17
Scientists from RWTH Aachen and ETH Zurich have developed a unique town game for the city of Regensburg. From August onwards it enables the history of this German city to be discovered easily by using a modified mobile phone. The game behaviour will be assessed to evaluate this way of conveying information.

Christoph Meier

“The ‘generation game’ or ’generation interactive’ has now arrived,” is Steffen P. Walz’s diagnosis. This also affects learning processes in general says the doctoral student at the ETH professor’s chair for CAAD (1) . That’s why he is working on interactive games that young adults also use to acquire reliable knowledge in a motivated way.

At a conference on Ubiquitous Computing in Tokyo in 2005, i.e. an event about the advance of computers into all areas of life, when Tico Ballagas, a colleague from the Media Computing Group of the Aachen University RWTH, asked Walz whether he was interested in collaborating on a town exploration game, he immediately agreed. The “REXplorer” project has made great progress since then (2) . From this August onwards tourists will be able to discover the city of Regensburg by playing thanks to this project.

But what is behind REXplorer? From the technical point of view the game is based on camera mobile phones additionally equipped with a navigation system, a sensor and analysis software, and housed in a specially designed case, the game controller. The upgraded mobile phones can contact a server at 29 locations in the old town centre of Regensburg.

The city’s spirit speaks from a mobile phone

To play the game, a city explorer borrows a suitable game controller at the Regensburg tourist information office and walks into town. On moving near to one of the nodes of the field of play that provides virtual coverage of the city, the mobile phone shows an increased heartbeat on its display. When sufficiently close, the player is contacted by the system and is asked to make a hand movement. There are four different hand movements to choose from. Depending on the gesture, a task related to the history of the locality is set.

For example one task is that a Domspatz, i.e. a cathedral choirboy, asks the player to take a love letter to a convent schoolgirl who is waiting in the cathedral garden. The player can do this by making an appropriate input gesture with his/her mobile phone. Another task is that an halting virgin, a reflection of her era, asks the player to question the great theologian Albertus Magnus whether it is permissible love someone without knowing anything about their downside.

Reconstructable through the Internet

The game has no dead ends even if the player is not able to solve all the tasks successfully, all that happens is that the player’s personal points score will be poorer. The game is also designed in such a way that certain tasks are intended to be solved by several players together. The winner at the end of the day is the one who has tracked down the most stories. After finishing the game, players can reconstruct their tour of discovery via the Internet. Participants can find their route through the city here, their photos and other information about the sightseeing highlights and the characters with whom the player came into contact.

The script for the Regensburg city discovery game with a mobile phone was written at ETH.

From August the town of Regensburg can be discovered using an upgraded mobile phone thanks to ETH research. (Photos: Steffen P. Walz)

The sequence of images reveals movement

The location-dependent recognition of hand movements is something special and is being used for the first time in a town game. It is based on software developed at ETH and adapted in Aachen, which can recognise movements based on the sequence of images from the mobile phone’s camera. Steffen P. Walz explains that “there are mobile phones that recognize movements with accelerometers, but the technology is different and has never before been integrated into an outdoor game.”

However, the challenge facing the ETH doctoral student lay not in developing special software, but in working out the rules for the game and its content. To do this he needed to collect a large amount of information, to write an extensive script, and also to organise texts and sound recordings. He was also responsible for designing the controller housing via which it is steered.

The mobile phones themselves were donated to ETH by the Nokia Company, which also contributed additional support for the game. REXplorer is operated by the Erlebnismuseum Regensburg Experience GmbH, a non-profit-making company. The game is also supported by the Swiss National Science Foundation within the "Mobile Information & Communication Systems (MICS)" project.

Play is researched

In the same way as REXplorer combines entertainment and information, there is also a connection between play and research. This is because the scientists use the data generated by the players to analyse the latters’ behaviour. These analyses are in turn designed to help improve comparable games and other town services.

However REXplorer did not simply start from nowhere. In the preparation stage Steffen P. Walz had already carried out opinion surveys among grammar school students in Stuttgart. These showed that there really was a willingness to take part in games such as REXplorer.

In this respect the ETH scientist also believes that the game’s concept could already be transferred to other places now. Walz would find the application of REXplorer to scientific topics really attractive. He had already developed the initial preparatory work in the “ETH Game” project (3) . For the time being an audio tour with podcasts will be offered for the first time this summer in Science City on the Hönggerberg campus. A really interactive Science City game is not yet in prospect, although the know-how would certainly exist. The ‘generation game' at ETH Zurich will have to wait a little longer before they can learn by playing.

(1 Steffen P. Walz and his projects at ETH: (
(2 Web site about Rexplorer: (
(3 Cf. the “ETH Life” report "ETH as a game”: (

Copyright 2000-2007 by ETH - Eidgenoessische Technische Hochschule Zurich - Swiss Federal Institute of Technology Zurich
!!! Dieses Dokument stammt aus dem ETH Web-Archiv und wird nicht mehr gepflegt !!!
!!! This document is stored in the ETH Web archive and is no longer maintained !!!