Overview

Location-based services provide data using a wireless local area network (e.g. WiFi) or a positioning system such as GPS. The general objective is to support an enhanced mobile experience for the person interacting within their physical environment. Location-based services use the location of an individual to deliver context sensitive information. A key theme that has emerged in the study of location-based games is a focus on human experiences rather than the traditional emphasis on the network infrastructure used to support the game.

In the Fugitive, this information is simply the player’s position in the game space. The Fugitive is a multiplayer, location-based, collaborative game that is played using mobile TabletPCs in a natural campus environment. The objective is to track and capture a hidden object called the Fugitive on a digital campus map using annotations for communication among one’s teammates.

Background

In the summer of 2005 we established the UBC Ubicomp group with the intent of exploring how location-based services may be designed to educate, entertain, and enable collaboration among users. The general idea was to form an interdisciplinary group composed of students, professors, and researchers from different departments to share and discuss experiences gained from our individual and collaborative projects.

In order to gain experience, we designed the Fugitive, a mobile game based on CatchBob!, where three team members move around a campus with the objective of finding and capturing a stationary, hidden, virtual object (Bob). The game is played on the EPFL campus in Lausanne, Switzerland.

The Platform

The dimensions of our game field are approximately 700 by 700 meters; however, not all areas of the playing field have WiFi coverage. The CatchBob! platform provides a web services interface to the game client implemented in Java.

During our testing phase, we used Intel Place Lab software for WiFi access point-based positioning to show a participant’s location on the game map. This software requires a calibration process called war driving to be conducted once. To calibrate, we walked around campus logging GPS coordinates and the signal strength of nearby WiFi access points. These logs were then uploaded to a central database, and using the coordinates and signal strength data, the location of the access points were estimated.

We switched to using pocket-sized Bluetooth-enabled GPS units for more accurate positioning during our field study.

Field Study

Participants were given a 10 minute introduction to the game in which they were provided with instructions about how to use the TabletPC and stylus, an explanation of the game objective, and the maximum time limit (30 minutes) provided for the game. During testing we found that carrying the TabletPC longer than thirty minutes could create a strain on one’s arm.

Lesson Learned from Field Study

We discovered that participants developed different purposes and strategies for the use of the map annotation area and the ink messaging area. The map area was used by the groups to convey location and positioning information (“I am here – X”), while the ink messaging area was used for communication regarding strategies between team mates.

There were not any complaints about carrying the TabletPC for 30 minutes, nor were there any accidents during campus navigation. We believe the TabletPC to be valuable for games that require displaying maps (e.g. a treasure hunt game involving the map of a neighbourhood) and for applications that showcase large displays.

From a social perspective, although only given brief pre-game instructions, participants understood how to play the game the first time. They understood the functionality of the game and how to effectively use and understand what the different UI features meant. Participants loved the idea of a mixed reality in which they interacted in the real world while chasing a virtual character.

Future Work

Based on our experience with the CatchBob! game platform, the UBC wireless network and Place Lab, we have begun work on a more general purpose platform for large scale ubiquitous computing environments (see Blackstock, Lea, & Krasic, 2006 in Publications). Unlike the CatchBob! and the Fugitive web service, this platform aims to provide an interoperable general purpose interface and model for all context aware computing environments based on a comprehensive survey of existing systems. We intend to use this new platform for future game development.

People

• Michael Blackstock
• Meghan Deutscher
• Matthias Finke
• Phillip Jeffrey
• Rodger Lea
• Kento Miyaoku

Undergraduates

• Gabriel Leung
• Si Colleen Qin
• Vincent Tsao
• William Tsui
• Steven Zhou

For Further Information

Contact Michael Blackstock