Seamful Game is a GPS and WiFi based game exploring the concept of seamfulness, in which we harness negative aspects of infrastructure technologies, which are normally concealed and unexplained, and present them as game features allowing users to explore and understand them.

Equator

University of Glasgow, UK

Matthew Chalmers, Marek Bell, Barry Brown, Malcolm Hall, Scott Sherwood, Paul Tennent

Demos at Ubicomp 2004, MobileHCI2004 and WMCSA 2004

The Concept

The Seamful Game is a GPS and WiFi based game played in the streets using PDAs. It began life as a project to test an idea about exploiting and exploring the seams of an 802.11 wireless network. Now approximately one year on, Bill is a fully featured multiplayer team game, which has been accused of being fun to play. Players must develop an understanding of the network coverage and the effect of signal strength in order to successfully play the game. In this way we are turning the patchy network coverage, which is usually seen as a problem to be overcome, or worse ignored, into a feature (indeed possibly the main feature) of the game.

The Game

The game consists of two teams of ‘runners’ each of whom is given a PDA equipped with 802.11b WiFi and GPS. Players travel around a designated area collecting digital ‘coins’ and uploading them in exchange for points. The team with the highest total at the end of the game wins. Each player is provided with a zoomable and panable map of the game area, displaying their own position and the positions of the other players in the game. ‘Coins’ appear all over this map, including those places not covered by the 802.11b wireless network. Players must use their GPS positioning to navigate to where the coin is displayed, and collect it using the 'pickup' button on the PDA interface. In

 order to gain the points from collecting the coin, players must then successfully upload it to the server. To do this requires the player to press the 'upload' button on their interface in an area where there is 802.11b coverage. It is with this distinction that we introduce the concept of seams to the players. Only by understanding the boundaries of the network, and the effect of signal strength on their ability to upload coins, and thus score points, will players be successful in winning the game. If players attempt to upload coins in an area not covered by WiFi, the upload fails and they loose all the coins they are carrying.

In order to encourage users to interact while playing the game, two additional features are provided, one collaborative and one competitive. The first is a collaborative upload. This feature allows users to upload coins simultaneously with other members of their team to receive a points bonus (each player receives the cumulative total points for the upload) and the more team members participate, the more points they stand to gain. The players are given a three second window in which to upload their coins, to get the bonus. The second feature added was the ‘Pick Pocket’. This proved one of the more popular and certainly one of the most discussed features of the whole system. The ‘Pick Pocket’ allows a player to steal coins from other players nearby. To use it a player must be inside network coverage, and use his or her GPS to get within 10 meters of another player (also within network coverage). He or she then presses the 'Pick Pocket' button on the PDA and the any ‘coins’ the victim is carrying but has not uploaded are transferred to the PDA of the perpetrator. Players may ‘Pick Pocket’ as many times they wish. As well as ‘Pick Pockets’, players face another hazard along the way. Scattered infrequently around the map are ‘Mines’. If a player moves to within 10 meters of a ‘mine’, it will detonate, causing the player’s PDA to be temporarily disabled. ‘Mines’ are displayed clearly on the map, but can be obscured by a large cluster of coins if the map is zoomed too far out. This means that mines can be hidden, but if players are suitably aware, they will be able to avoid them. One method of staying safe from ‘Mines and ‘Pick Pockets’ is the ‘Shield’. When a player presses the 'shield' button on their PDA, they cannot be affected for 20 seconds. However once the time runs out, the ‘shield’ must be ‘recharged’ in an area of network coverage before it can be used again.

Along the top of the PDA’s display is shown state information. The player’s own score, the two team’s total scores, the number of coins currently carried and the time remaining in the game is shown, along with the current signal strength and the number of GPS satellites available (equating roughly to GPS accuracy). Finally, the players are provided with an instant messaging system. Players can scribble notes, using Pocket PC2003’s built in handwriting recognition (or explicitly type them), then send to either a whole team or an individual.

Displaying the Signal Strength

Two approaches were taken to displaying the 802.11b signal strength. As mentioned in the previous section, a subjective view of signal strength is provided; this is in the mobile phone-esque form of signal bars and shows a player’s immediate signal strength. This actually served a dual purpose. It was reasoned that this would be easy to understand, and perhaps more usefully provided a connection to mobile phones, helping us to explain the idea of seams in networks in easy to understand terms (e.g. Highlighting the idea of being outside network coverage, or pretending to be…and missing a call). The second method of display used was slightly more complex. The idea of signal coverage maps, such as those used by mobile phone companies, was taken and expanded to create something more dynamic. Traditionally these maps show us the best possible coverage, not taking into account the fact, that wireless networks are distinctly malleable. In this system, players build up a collaborative aggregate map of the signal strength across the game area as the game is played. By leveraging the power of the technology we are using, we are able to display the most up to the minute data possible, as the map is being constantly updated from all the players within network range. This second display gives players a more objective view of the network. Instead of thinking ‘I can upload my coins here’ they are now able to think ‘I can upload my coins there’. This dynamic mapping has great potential for system understanding. Imagine if a phone company with thousands of users in every node could see these maps of their network. The granularity could be extremely fine, and far more accurate than the current systems mentioned earlier.