Key research themes and publications

Trajectories through user experiences

A conceptual framework for understanding and designing complex cultural user experiences in terms of multiple trajectories. Trajectories capture the idea of establishing a coherent journey through an extended experience that combines many different spaces, times, roles and interfaces. The framework identifies the different kinds of transitions and traversals that may occur along a trajectory and shows how diverging, converging and crossing trajectories describe important aspects of multi-user experiences and reflect the tension between pre-scripted narrative and interactivity.

• From interaction to trajectories (Benford, Giannachi, Koleva and Rodden, Proceedings of CHI 2009) introduces the trajectories conceptual framework. The paper reflects upon four experiences, Desert Rain, Uncle Roy all Around You, fairground: Thrill Laboratory, and Day of the Figurines. It introduces the core approach of trajectories along with key transitions and traversals. It also introduces canonical and participant trajectories and discusses interleaved trajectories. Winner of a CHI 2009 best paper award.

• Temporal Trajectories in Shared Interactive Narratives (Benford & Giannachi, Proceedings of CHI 2008). A precursor to the general trajectories framework that focuses specifically on trajectories through time. This paper introduces a conceptual framework for reasoning about time in narrative driven experiences such as games, hypermedia stories and interactive performances based upon the concept of temporal trajectories that express different mappings between fictional story time and actual clock time. Three kinds of temporal trajectory, canonical, participant and historic, enable us to reason about issues such as pacing, synchronisation and fictional time travel.

• Flypad: Designing Trajectories in a Large-Scale Permanent Augmented Reality Installation (Flintham et al, Proceedings of ECSCW 2011). Presents and ethnographic study of Flypad, a twelve player augmented reality game that is a permanent installation at The Public art gallery. The study reveals how the artists designed a trajectory through the experience, how this was experienced by visitors, and how it has evolved over time.

• Creating the Spectacle: Designing Interactional Trajectories through Spectator Interfaces (Benford et al, ACM Transactions on CHI, 2011). An ethnographic study reveals how professional artists created a spectator interface for the interactive game Day of the Figurines, designing the size, shape, height and materials of two tabletop interfaces before carefully arranging them in a local setting. We consider how the artists worked with a multi-scale notion of interactional trajectory that combined trajectories through individual displays, trajectories through a local ecology of displays, and trajectories through an entire experience.

Thrilling interactions

A series of projects exploring the theme park as a microcosm for entertainment computing, including developing new forms of interactive thrill ride controlled by biosensing, broadcasting ride experiences to spectators, and new approaches to collaborative souvenir production.

• Uncomfortable Interactions (Benford, Greenhalgh, Walker, Giannachi, Marshall, Rodden, Proceedings of CHI 2012) explores the deliberate use of discomfort to create interactions that are more entertaining, enlightening or foster social bonding. Identified four primacy aspects of discomfort, visceral, cultural, control and intimacy. Considers how discomfort may be embedded into an overall experience and also explores ethical justifications and issues. Winner of a CHI 2012 best paper award.

• Automics: souvenir generating photoware for theme parks (Durrant, Rowland, Kirk, Benford, Fischer, McAuley, Proceedings of CHI 2011) describes the design and evaluation of the Automics souvenir system that combines visitors own photos within those of fellow group members alongside images from on-ride photo systems, enabling people to annotate and caption them and then create individual photostories of their ride experiences. Winner of a CHI 2011 best paper award.

• Breath Control of Amusement Rides (Marshall, Rowland, Egglestone, Benford, Walker, McAuley, Proceedings of CHI 2011). Describes a study of a prototype breath controlled amusement ride in the form of a bucking bronco and proposes tactics for using breathing to create thrilling rides.

• The Gas Mask: A Probe for Exploring Fearsome Interactions (Marshall, Walker, Benford,Tomlinson, Egglestone, Reeves, Brundell, Tennent, Cranwell, Harter, Longhurst, Proceedings of alt.chi 2011) describes the design of a breath-sensing and Wi-Fi enables gas mask as a technology probe for exploring fearsome interactions.

• Performing Thrill: Designing Telemetry Systems and Spectator Interfaces for Amusement Rides (Schnadelbach, Rennick Egglestone, Reeves, Benford, Walker and Wright, Proceedings of CHI 2008) studies a specific spectator interface (a wearable telemetry system for fairground rides that conveyed video, audio, heart-rate and acceleration data to large public screens) showing how it reconfigured the relationships between riders, spectators and ride operators and raising the need for selective and careful revealing of an individuals experience to the public.

Interaction in public

The increasingly public nature of interaction, in museums, galleries, theme parks, clubs, bars, and on the city streets, raises new challenges for HCI concerning the nature of spectatorship and the framing of interaction in public.

• Designing the spectator experience (Reeves, Benford, OMalley and Fraser, Proceedings of CHI 2005) explores different strategies for designing he spectator view of interaction. A comparison of different approaches to hiding, transforming, revealing or even amplifying manipulations of an interface and their consequent effects reveals four contrasting approaches referred to as secretive, expressive, magical and suspenseful. Winner of a CHI 2005 best paper award.

• The frame of the game: blurring the boundary between fiction and reality in mobile experiences (Benford, Crabtree, Reeves, Flintham, Drozd, Sheridan and Dix, Proceedings of CHI 2006) explores through a study of the game Uncle Roy All Around You some of the different ways in which public interaction can be framed, leading to a distinction between audience and possibly unwitting bystanders, and considering ambiguous framing can raise new opportunities and also risks for playful experiences.

• Creating a Live Broadcast from a Virtual Environment (Greenhalgh, Benford, Taylor, Bowers, Walker & Wyver, Proceedings of SIGGRAPH 1999) describes the design and collaborative use of virtual cameras so as to create a public broadcast view of a live gameshow in a collaborative virtual environment as an experiment into what we referred to as Inhabited Television

Time, history and the evolution of interfaces

The temporal aspects of interaction are complex but important, from the short term impacts of delays, to the synchronisation of different participants experiences, to new approaches to interweaving recorded interactions with live ones, to the long term evolution of systems.

• Temporal Trajectories in Shared Interactive Narratives (Benford & Giannachi, Proceedings of CHI 2008) introduces a conceptual framework for reasoning about time in narrative driven experiences such as games, hypermedia stories and interactive performances based upon the concept of temporal trajectories that express different mappings between fictional story time and actual clock time. Three kinds of temporal trajectory, canonical, participant and historic, enable us to reason about issues such as pacing, synchronisation and fictional time travel.

• Revealing delay in collaborative environments (Gutwin, Benford, Dyck, Fraser, Vaghi, & Greenhalgh, Proceedings of CHI 2004) describes experiments that show that revealing the presence and nature of delay at the interface can support participants in developing coping strategies, leading to proposals for new interface widgets,

• Temporal links: recording and replaying virtual environments (Greenhalgh, Purbrick, Benford, Craven, Drozd & Taylor, Proceedings of ACM Multimedia 2000) presents a techniques for making system recordings of events in collaborative virtual environments and then playing them back in live virtual environments at various speeds, sizes and with different presentations, so that live participants can follow and react to them, which in turn may generate further nested recordings and so on.

• The evolution of buildings and implications for the design of ubiquitous domestic environments (Rodden & Benford, Proceedings of CHI 2003), draws on the work of the architect Stewart Brand to reflect on the ways in which interactive technologies in the home form part of an evolving ecology and proposes how we might consider the evolution of such technologies in terms of different layers of time.

• Are You Watching This Film or What?: Interruption and the Juggling of Cohorts (Tolmie, Crabtree, Rodden & Benford, Proceedings of CSCW 2008) presents an ethnographic study of how participants in the text messaging adventure game Day of the Figurines managed and accounted for interruptions from the game.

• Inferring player engagement in a pervasive experience (Fischer & Benford, proceedings of CHI 2009) presents a study using the experience sampling method to investigate the prediction of player engagement to address temporal issues arising from the long-term character of pervasive experiences such as interruptibility, mutual player state awareness, disengagement and synchronization on re-engagement.

Space and embodiment in collaborative virtual environments

This work proposes conceptual frameworks for designing and structuring virtual environments and avatars so as to support rich, dynamic and scalable online social interaction.

• Collaborative Virtual Environments (Benford, Greenhalgh, Rodden & Pycock, Communications of the ACM, 2001) provides a brief introduction to and overview of CVEs.

• A Spatial Model of Interaction in Large Virtual Environments (Benford & Fahlen, Proceedings of ECSCW 1993) introduces spatial fields called aura, focus and nimbus as a way of managing awareness and hence mediating communication in collaborative environments. This set of concepts is intended to be relatively small and straightforward while being directly implementable in software, and yet also powerful enough to support diverse and potentially large-scale communication situations.

• MASSIVE: a collaborative virtual environment for teleconferencing (Greenhalgh & Benford, ACM Transactions on Computer-Human Interaction, TOCHI, September 1995, Volume 2 Issue 3) presents an example implementation of the spatial model of interaction in the MASSIVE system.

• Crowded Collaborative Virtual Environments (Benford & Greenhalgh, Lloyd, Proceedings of CHI 1997) introduces an extension to the spatial model of interaction called third party objects that expresses the properties of dynamic groups of participants or objects, providing different membership policies, introducing various affects on awareness within the groups, and also providing a common aggregated view of their activity to those outside. The aim is to support greater scalability of collaborative virtual environments, ultimately leading to the introduction of large dynamic crowds of avatars.

• User Embodiment in Collaborative Virtual Environments (Benford, Bowers, Fahlen & Greenhalgh, Proceedings of CHI 1995) introduces a general framework for designing user embodiments (avatars) in collaborative virtual environments addressing the issues of conveying presence, location, identity, activity, availability, history of activity, viewpoint, actionpoint, gesture, facial expression, voluntary versus involuntary expression, degree of presence, reflecting capabilities, physical properties, active bodies, time and change, manipulating ones view of others, representation across multiple media, autonomous and distributed body parts, truthfulness and efficiency.

• Object-focused interaction in collaborative virtual environments (Hindmarsh, Fraser, Heath, Benford & Greenhalgh, ACM Transactions on Computer-Human Interaction, TOCHI, Volume 7 Issue 4, December 2000) describes a series of naturalistic studies of participants carrying out a design task in a collaborative virtual environment that reveal problems arising from limited fields of view leading to proposals for extending and enhancing avatars.

Ambiguity and uncertainty

Concerns the nature of uncertainty in human-computerinteraction, especially where invisible sensing systems are used, and therelated idea of exploiting ambiguity as a resource in interface design.

• Deception and Magic in Collaborative Interaction (Marshall, Benford, Pridmore, Proceedings of CHI 2010) presents a framework to explain how collaborative interfaces can be designed to support deception as part of the performance of illusion and stage magic.

• Ambiguity as a resource for design (Gaver, Beaver & Benford, Proceedings of CHI 2003) argues that, in contrast to the traditional view in HCI, ambiguity can in fact be a useful resource for the design of user interfaces, engaging and provoking users and requiring them to interpret the interface. The paper argues that there are three broad types of ambiguity to be considered - ambiguity of information, context and relationship - and proposes a set of design tactics.

• Expected, sensed, and desired: A framework for designing sensing-based interaction (Benford, Schnadelbach, Koleva, Anastasi, Greenhalgh, Rodden, Green, Ghali, Pridmore, Gaver, Boucher,Walker, Pennington, Schmidt, Gellersen & Steed, ACM Transactions on Computer-Human Interaction, TOCHI, Volume 12 Issue 1, March 2005) provides a framework for designing sensing-based interfaces. Illustrated with three case studies - interactive flashlights, the augurscope, and the drift table - designers are encouraged to systematically explore the partial overlaps between the expected movements of an interfaces, those that can sensed and those that are actually desired for the application.

• Can you see me now? (Benford, Crabtree, Flintham, Drozd, Anastasi, Paxton, Tandavanitj, Adams & Row-Farr, ACM Transactions on Computer-Human Interaction, TOCHI, Volume 13 Issue 1, March 2006) presents an ethnographic study of a mobile mixed reality game in which mobile runners on the streets of the city used handheld computers with GPS and wireless networking to chase online players through a virtual model of this city. The study revealed the profound impacts of uncertainty of coverage and accuracy on the experience leading to five different design strategies: removing, hiding, managing, revealing and exploiting uncertainty.

• Extending Authoring Tools for Location-Aware Applications with an Infrastructure Visualization Layer (Oppermann, Broll, Capra & Benford, Proceedings of Ubicomp 2006) responds to previous studies of experiences such as Can You See Me Now and Hitchers by exploring how we can extend authoring tools for mobile applications with an infrastructure visualisation layer that enables designers to reason about the likely impact of variations in the coverage and accuracy of positioning and wireless communications on their applications.

• The Error of Our Ways: The Experience of Self-Reported Position in a Location-Based Game (Benford, Seager, Flintham, Anastasi et al, Proceedings of Ubicomp 2004) presents a study of how mobile participants in the experience Uncle Roy All Around You made use of self-reported positioning when communicating with remote online players. The study shows that players would often report where they were going rather than where they actually were and discusses the implications for the design of location-aware experiences.

• Hitchers: Designing for Cellular Positioning (Drozd, Benford, Tandavanitj & Wright, Proceedings of Ubicomp 2006) discusses early experience with a mobile phone game in which players created, shared and carried digital hitch hikers, that revealed some of the seams that need to be understood when designing for cellular positioning.

• The ins and outs of home networking: The case for useful and usable domestic networking (Grinter, Edwards, Chetty, Poole, Sung, Yang, Crabtree, Tolmie, Rodden, Greenhalgh, Benford, ACM Transactions on CHI) presents an ethnographic study of work involved in people managing their own home networks.

Permeable boundaries between the real and virtual

Transforms the conventional computer screen into a permeable boundary between real and virtual worlds and enables participants to project their presence from the real to the virtual and vice versa

• Understanding, Constructing Shared Spaces with Mixed-Reality Boundaries (Benford, Greenhalgh, Reynard, Brown & Koleva, ACM Transactions on Human Computer Interaction, TOCHI, Volume 5, Issue 3, 1998) introduces the concept of mixed reality boundaries as a generic approach to connecting real and virtual worlds and introduces a set of underlying boundary properties that enable us to define many different kinds of connection,

• Traversable Interfaces Between Real and Virtual Worlds (Koleva, Schnadelbach, Benford & Greenhalgh, Proceedings of CHI 2000) extends the idea of mixed reality boundaries with the further concept of traversable interfaces, permeable physical projection interfaces that are intended to support the illusion of participants stepping into and out of projected images of virtual worlds.

• Orchestrating a Mixed Reality Performance, (Koleva, Taylor, Benford, Fraser, Greenhalgh, Schnadelbach, vom Lehn, Heath, Row-Farr & Adams, Proceedings of CHI 2001) presents an ethnographic study of the performance Desert Rain (a collaboration with Blast Theory) that deployed an example traversable interface, a physically permeable projection screen called the rain curtain that was composed of a fine water spay through which performers could move, so that they appeared to physically emerge from and disappear into a virtual world.

• Moving Office: Inhabiting a Dynamic Building (Schnadelbach, Penn, Steadman,Steve Benford, Koleva & Rodden, Proceedings CSCW 2006) Presents a study of the use of mixed reality boundaries in an office environment to create a persistent and navigable media space in which video views of offices are embedded into a 3D virtual world which is in turn permanently projected back into the offices.

Pervasive games and performances

Have involved a series of collaborations with creative partners to create new forms of art, entertainment and learning that combine mobile and online interaction.

• Performing Musical Interaction: Lessons from the Study of Interactive Theatrical Performances (Benford, the Computer Music Journal) discusses how various HCI frameworks (including expected sensed desired; spectator interfaces; and trajectories) apply to the design of future musical instruments.

• Interweaving mobile games with everyday life (Bell, Chalmers, Barkhuus, Hall, Sherwood, Tennent, Brown, Rowland, Benford, Capra, Hampshire, Proceedings of CHI 2006) describes the design and study of a location-based game and how it came to be embedded into the patterns of daily life. Nominated for a CHI 2006 best paper award.

• Bridging the Physical and Digital in Pervasive Gaming (Benford, Magerkurth & Ljungstrand, Communications of the ACM, 2005) provides a brief introduction to and overview of pervasive gaming.

• Where On-Line Meets On-The-Streets: Experiences With Mobile Mixed Reality Games (Flintham, Anastasi, Benford, Hemmings, Crabtree, Greenhalgh, Rodden, Tandavanitj, Adams, Row Farr, Proceedings of CHI 2003) presents a study of Can You See Me Now, a game of chase in which mobile players, equipped with handheld computers with GPS and wireless networking, ran through the city streets chasing online players who ran through the streets of an online virtual model of the city.

• The frame of the game: blurring the boundary between fiction and reality in mobile experiences (Benford, Crabtree, Reeves, Flintham, Drozd, Sheridan and Dix, Proceedings of CHI 2006), presents Uncle Roy All Around You, a performance in the form of a game in which street players searched the city for the mysterious Uncle Roy, guided by online players as well as ambiguous clues from the game that encouraged them that blurred the boundaries between fiction and reality.

• Life on the Edge: Life on the Edge: Supporting Collaboration in Location-Based Experiences (Benford, Rowland, Flintham, Drozd, Hull, Reid, Morrison & facer, Proceedings of CHI 2005) presents a study of a educational location-based game that transformed a school playing field into a virtual savannah so that groups of children could role-play lions.

• In support of City Exploration (bedwell, Schnadelbach, Benford, Rodden, Koleva, Proceedings of CHI 2009) presents a study of the experience Anywhere that allowed participants to explore an urban area, tying together information not normally available, new points of views and interaction embedded into physical places. Guided by unseen, on-the-street performers in an ongoing conversation maintained over mobile phones, they gained access to locative media and staged performances. Our analysis demonstrates how Anywhere produced engaging and uniquely personalised paths through a complex landscape of content, negotiated by the performer-participant pair around various conflicting constraints.

• Using Fast Interaction to Create Intense Experiences (Marshall, Benford, Proceedings of CHI 2011) describes a study of how physical exertion related to digital media in I Seek the Nerves Under Your Skin, an artwork in which participants have to run to a frenzy in order to listen to an increasingly frenzied poem.