T. C. Nicholas Graham

Using games to increase exercise motivation

In recent years, there has been significant work in integrating physical activity into video games. One goal of this work has been to help motivate sedentary people to be more physically active. Konamis Dance Dance Revolution and Nintendos Wii Sports have shown that exercise games can be both fun and commercially successful. To date, however, there has been little attempt to investigate what properties of exercise games will help motivate sedentary people to start and continue exercise programs. This paper reviews the literature on exercise motivation and derives from it requirements for computer-aided exercise games. The paper then introduces the new Life is a Village exercise game, and uses it to illustrate how these requirements can be met.

Use of eye movements for video game control

We present a study that explores the use of a commercially available eye tracker as a control device for video games. We examine its use across multiple gaming genres and present games that utilize the eye tracker in a variety of ways. First, we describe a first-person shooter that uses the eyes to control orientation. Second, we study the use of eye movements for more natural interaction with characters in a role playing game. And lastly, we examine the use of eye tracking as a means to control a modified version of the classic action/arcade game Missile Command. Our results indicate that the use of an eye tracker can increase the immersion of a video game and can significantly alter the gameplay experience.

Efficient distributed implementation of semi-replicated synchronous groupware

The Model View Controller (MVC) architecture has proven to be an effective way of organizing synchronous groupware applications. Distributed implementations of MVC, however, can suffer from poor performance. This paper demonstrates how optimized semi-replication of MVC architectures can lead to good performance over both local and wide area networks. We present a series of optimizations to network communication based on specific communication properties of groupware. These optimizations have been implemented in the Clock groupware development toolkit, allowing programmers to develop applications directly in the high-level MVC style, with Clock automatically providing optimized performance. Timings of an application developed in Clock show that usable speed was obtained in a highly interactive groupware application running between Toronto and Calgary, with a typical latency of 190 ms per round trip message. The paper discusses the tradeoffs involved in the algorithms, and presents timings to demonstrate the effectiveness of the different approaches. The timings show that when running over a wide area network, the best optimization can achieve a factor 60 speedup over the naive implementation of distributed MVC.

Designing action-based exergames for children with cerebral palsy

Children with cerebral palsy (CP) want to play fast-paced action-oriented videogames similar to those played by their peers without motor disabilities. This is particularly true of exergames, whose physically-active gameplay matches the fast pace of action games. But disabilities resulting from CP can make it difficult to play action games. Guidelines for developing games for people with motor disabilities steer away from high-paced action, including recommendations to avoid the need for time-sensitive actions and to keep game pace slow. Through a year-long participatory design process with children with CP, we have discovered that it is in fact possible to develop action-oriented exergames for children with CP at level III on the Gross Motor Function Classification Scale. We followed up the design process with an eight-week home trial, in which we found the games to be playable and enjoyable. In this paper, we discuss the design of these games, and present a set of design recommendations for how to achieve both action-orientation and playability.

Real-time groupware in the browser: testing the performance of web-based networking

Standard web browsers are becoming a common platform for delivering groupware applications, but until recently, the only way to support real-time collaboration was with browser plug-ins. New networking approaches have recently been introduced - based on re-purposed techniques for delivering web pages (Comet), or integration of real-time communication directly into the browser (HTML5 WebSockets). Little is currently known, however, about whether these new approaches can support real-time groupware. We carried out a study to assess the performance of the three different networking approaches, based on a framework of groupware requirements, in several network settings. We found that web-based networking performs well - better than plug-in approaches in some cases - and can support the communication requirements of many types of real-time groupware. We also developed two groupware applications using Comet and WebSockets, and showed that they provided fast and consistent performance on the real-world Internet. Our studies show that web-based networking can support real-time collaboration, and suggest that groupware developers should consider the browser as a legitimate vehicle for real-time multi-user systems.

Design of an exergaming station for children with cerebral palsy

We report on the design of a novel station supporting the play of exercise video games (exergames) by children with cerebral palsy (CP). The station combines a physical platform allowing children with CP to provide pedaling input into a game, a standard Xbox 360 controller, and algorithms for interpreting the cycling input to improve smoothness and accuracy of gameplay. The station was designed through an iterative and incremental participatory design process involving medical professionals, game designers, computer scientists, kinesiologists, physical therapists, and eight children with CP. It has been tested through observation of its use, through gathering opinions from the children, and through small experimental studies. With our initial design, only three of eight children were capable of playing a cycling-based game; with the final design, seven of eight could cycle effectively, and six reached energy expenditure levels recommended by the American College of Sports Medicine while pedaling unassisted.

A dimension space for the design of interactive systems within their physical environments

This paper introduces a Dimension Space describing the entities making up richly interactive systems. The Dimension Space is intended to help designers understand both the physical and virtual entities from which their systems are built, and the tradeoffs involved in both the design of the entities themselves and of the combination of these entities in a physical space. Entities are described from the point of view of a person carrying out a task at a particular time, in terms of their attention received, role, manifestation, input and output capacity and informational density. The Dimension Space is applied to two new systems developed at Grenoble, exposing design tradeoffs and design rules for richly interactive systems.

Relational views as a model for automatic distributed implementation of multi-user applications

Multi-user applications support multiple users performing a related task in a distributed context. This paper describes Weasel, a system for implementing multi-user applications. Weasel is based on the relational view model, in which user interfaces are specified as relations between program data structures and views on a display. These relations are specified in RVL, a high-level, declarative language. Under this model, an application program and a set of RVL specifications are used to generate a multi-user application in which all issues of network communication, concurrency, synchronization, and view customization are handled automatically. These programs have a scalable distribution property, where adding new participants to a session does not greatly degrade over-all system performance. Weasel has been implemented, and was used to generate all examples in this paper. CR Categories: D.2.2 (Software Tools and Techniques for User Interfaces); D.1.1 (Applicative Programming); D.3.4 (Compilers and Runtime Environments) General Terms: Human Factors, Languages Additional

Flexibly Mapping Synchronous Groupware Architectures to Distributed Implementations

Design-level architectures allow developers to concentrate on the functionality of their groupware application without exposing its detailed implementation as a distributed system. Because they abstract issues of distribution, networking and concurrency control, design-level architectures can be implemented using a range of distributed implementation architectures. This paper shows how the implementation of groupware applications can be guided by the use of semantics-preserving architectural annotations. This approach leads to a development cycle that involves first developing the functionality of the application in a local-area context, then tuning its performance by setting architecture annotations. The paper concludes with timing results showing that architectural annotations can dramatically improve the performance of groupware applications.

The Vista environment for the coevolutionary design of user interfaces

User centered design requires the creation of numerous design artifacts such as task hierarchy, task-oriented specification, user interface design, architecture design and code. It is increasingly accepted that such artifacts cannot be created in isolation, but instead incrementally coevolve, where information obtained from the development of one artifact contributes to the development of the others. In user interface development, these artifacts are typically developed by different people with different backgrounds, hindering the communication necessary for coevolution. This paper demonstrates how different design artifacts can be linked, exposing their common elements. Such links can be developed despite the differing points of view and differing levels of detail of the design artifacts. This paper describes Vista, a prototype tool for examining the links between design artifacts, and demonstrates how making these links explicit supports coevolutionary design.