The Fugitive, formerly known as Chase Bob, is a location-based Wifi game played on the UBC campus. The objective of this game is for a team of three players to seek, track, and surround a virtual person, Bob. In order to communicate with the other team members and to determine the position of all parties, each player uses a tablet PC that is connected to the UBC Wifi network.

When the 496 project team was enlisted by the UBC Ubicomp group to complete game implementation, the software of The Fugitive was at the end of a development iteration phase. Most of the client (user) components were finished for playability; however, the game had not been tested on the UBC campus. Therefore, positioning accuracy, Wifi connectivity, and usability were all indeterminate. In addition, the server replay tool that was vital for future research analysis had very limited functionality, and significant feature additions were necessary.

Following field testing, a number of tasks were done to improve the game. To increase positioning accuracy, the project team war-drove throughout the UBC campus and mapped GPS locations to Wifi access points. The connectivity of the Wifi network was characterized, and a new playing field for the game was determined. Software modifications for game usability, such as game parameters and UI features, were also implemented. The replay tool was changed to include ink widget display, stroke display, scroll bar of ink history, and Bob's location. Throughout the project, a primary challenge was Wifi connectivity and UBC wireless login for the game. This was solved with the addition of a software component to log into the UBC wireless network automatically whenever connection is lost. These modifications improved the usability of the game, and the 496 team effectively met the objectives of the project as determined by the Ubicomp group. The resulting state of The Fugitive game is playable and analyzable based on recent team testing.

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Project Task Summary

The following provides a quick summary of the tasks performed in this projects and the objectives that were achieved.

Field Testing

At the beginning of the 496 project, the game was at the end of an iterative development phase, and it was important to determine the current usability as well as the technical state of the game via field testing. From these tests, the following information was found: Positioning. The Fugitive uses a map of UBC as its game background and displays all 3 players at their detected location. The positioning accuracy as measured from the field tests was poor. The difference between the detected location and the actual location of players usually ranged between 40-50 meters. For some locations, the position inaccuracy was as significant as 100 meters. There was also a skipping behavior exhibited by players on the map. Connectivity. During the field tests, the game was frequently disconnected, which prompted players to manually sign in to the UBC wireless network numerous times through UBC's wireless login website. This was very troublesome, as the players were constantly interrupted in the game for login. Usability. The game parameters that navigated Bob proved to be too difficult for players to capture him. There were a number of UI annoynances that also needed to be fixed. The playing area was too big to play the game, and the 30-minute alloted time for playing the game was overrun. The game couldn't be completed within 2 hours. These issues needed to be addressed and resolved for game playability.

Location Accuracy

The most probable explanation for location inaccuracy was that only a limited number of UBC Wifi points were used to determine the position of the players, as only certain Wifi points were in the Place Lab database library used by The Fugitive game. To solve the problem, war-driving was done throughout the UBC campus. This increased the number of access points pertaining to the UBC campus area to include around 1000 new beacons, increasing the total number of access points at UBC from 2400 to 3400. The result of adding these new access points was very positive. Positioning accuracy for The Fugitive now improved to between 15 to 20 meters of error for most areas, and around 30 to 50 meters in locations of low Wifi signal strength.

Connectivity

The game relies on wireless connection to synchronize players' messages and locations. Therefore, the playing area should be located within a reliable wireless network. Also, when players are disconnected from UBC wireless, reconnecting should be as fast as possible. To find a reliable wireless connection area, UBC wireless IT was contacted, and it was discovered that UBC is covered 2 networks geographically, with one located on the north side of the campus, and the other located on the south. The border between these two networks has very poor connectivity. The north side of the network is also more established and appears to have more access points. Therefore, a new playing area was mapped, outlining areas of good connectivity, and informing players of poor connectivity via colored border zones graphically. To alleviate the pain of manual login experienced by users every time the game is disconnected from the UBC wireless network, an automatic login component was developed in Java and added to the game. When the game is being played, this component acts as an agent that automatically logs into the UBC wireless network using the player's CWL username and password whenever network connectivity is lost. If the component cannot log in, it continues its attempts at a period of every 10 seconds until a successful login is completed. With a new playable area and the addition of the UBC login component, connectivity has been improved drastically. Previously, users suffered from long periods of connectivity failure and the pain of manually logging into the UBC wireless network. Now, these effects have been minimized. The latest field testing demonstrated that these connectivity improvements have made the game much more enjoyable.

Game Parameters

The game parameters of The Fugitive determine the speed and movement of Bob. However, the original game parameters made the game too difficult to play. These parameters allowed Bob to run very fast away from the players, and enabled Bob to detect players from far way. It was unreasonable for players to run at top speeds while carrying a tablet. Therefore, the game parameters were modified to more reasonable values as determined through testing. A number of paramaters were modified. Bob's speed was lowered from 2.0 meters per second to 0.75 meters per second. Also, Bob's safety distance was decreased from 150 meters to 100 meters. The catch distance and maximum distance between players for capturing Bob were both lowered to make the game easier and more enjoyable to play.

UI and Related Usability Changes

Game paramaters were originally embedded in the Java code, making them difficult to modify. Since the server and client game parameters may differ from game to game, the software is changed to read parameters from a configuration file. This way, parameter values can be changed without recompiling the code for the game. The lack of a game start notification was identified by members of the UBIcomp group. Without the notification, new players would not intuitively know to synchronize their client game components with the server, and quite easily experience frustration. UI changes were made to the map such that the initial map displayed explicitly states for players to synchronize with the server by pressing the synchronization button. Once this button is pressed, another bold message notifies the user that the game has started. Following this, the playable map is displayed, and the game begins

Replay Tool

The replay tool is an important server component needed for collecting and analyzing game play data to advance strategy, collaboration, located-awareness research. At the beginning of the 496 project, the functionality of the tool was very limited. It was only capable of displaying the locations of the players during game play. The following changes were made to the tool as a result of this 496 project: Strokes logging and display Ink message logging and display through ink widget Colored ink ticks in the timer scroll bar to indicate ink message activity New drop down menu of usability features such as rewind, fast forward, and play Tracking and displaying Bob Better indication of distances travelled and game time Here's a screen shot of the replay tool at work:

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