From Interaction to Trajectories

1. From Interaction to Trajectories Steve Benford Mixed Reality Laboratory University of Nottingham

2. Desert Rain (1997)

3. Uncle Roy All Around You (2003)

4. Fairground: Thrill Laboratory (2006)

5. Day of the Figurines (2006)

6. Trajectories • All four experiences combine interactivity with live performance • They also exhibit complex and extended spatial and temporal structures • They are unified by the approach of creating a coherent journey through the experience • Building on recent studies of interactive exhibits, these journeys can be described in terms of trajectories

7. Mixed Reality Continuum (Milgram and Kishino) Virtual Reality Augmented Virtuality Augmented Reality (Everyday) Reality immersion ubiquity Our experiences combine multiple points on the continuum to form complex hybrid space through which participants move Trajectories through hybrid space

8. The timing of interactions as perceived by the participant Perceived time The times at which a participant chooses or is able to interact Interaction time The times at which the narration is made available Schedule time The temporal structure of the narration of the story Plot time The temporal structure of the underlying story world Story time Trajectories through hybrid time Time as perceived by the participant Time as conceived by the author

9. Street players Participants Online players Actors Performers Orchestrators Audience Spectators Bystanders Trajectories through roles each role follows its own trajectory and there are trajectories between roles

10. Trajectories through interfaces • Interfaces are designed and also arranged to establish a trajectory of interaction

11. Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

12. beginnings Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

13. Role and interface transitions beginnings Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

14. Role and interface transitions Temporal episodes beginnings Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

15. Role and interface transitions Physical-virtual traversals Temporal episodes beginnings Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

16. Role and interface transitions Physical-virtual traversals Temporal episodes beginnings Access to physical resources Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

17. Role and interface transitions Seams Physical-virtual traversals Temporal episodes beginnings Access to physical resources Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

18. Role and interface transitions Seams endings Physical-virtual traversals Temporal episodes beginnings Access to physical resources Transitions and Traversals Trajectories have to negotiate various transitions and traversals during which continuity may be at risk

19. Negotiating Trajectories Canonical trajectory Participant trajectory Canonical and participant trajectories represent an author’s ideal journey and a participant’s actual journey respectively

20. Negotiating Trajectories Canonical trajectory Interactivity drives divergence Participant trajectory Canonical and participant trajectories represent an author’s ideal journey and a participant’s actual journey respectively

21. Negotiating Trajectories Orchestration drives convergence Canonical trajectory Participant trajectory Canonical and participant trajectories represent an author’s ideal journey and a participant’s actual journey respectively

22. Interleaving Trajectories Participant ‘red’ Participant ‘blue Multiple trajectories can represent different participants or different applications

23. Mutual awareness and encounters when trajectories come together Interleaving Trajectories Participant ‘red’ Participant ‘blue Multiple trajectories can represent different participants or different applications

24. Interleaving Trajectories Participant ‘red’ Participant ‘blue Steer trajectories apart to avoid contention or to minimise distractions and interruptions Multiple trajectories can represent different participants or different applications

25. Pacing involves keeping trajectories together Interleaving Trajectories Participant ‘red’ Participant ‘blue Multiple trajectories can represent different participants or different applications

26. Summary of Trajectories • A trajectory describes a journey through an extended user experience emphasising continuity and coherence • Trajectories pass through hybrid structures of space, time, roles and ecologies of interfaces • Trajectories have to cross key transitions including beginnings, endings, role and interface transitions, physical-virtual transitions, temporal episodes, physical resources and seams • Canonicaltrajectories and participant trajectories represent author and participant control and diverge and converge due to interactivity and orchestration • Interleaved trajectories describe collaborative and/or multi-tasking situations and address encounters, awareness, separation, pacing and prioritisation

27. Putting Trajectories to Work • Providing sensitising concepts for empirical studies • A vehicle for compiling craft knowledge • Identifying requirements for new technologies • Towards a dramaturgy of interactive user experience

28. ‘Serious’ experiences? • Cultural experiences may provoke reflection and debate • Addressing challenging themes • Using ambiguity to provoke interpretation • Wider applications of trajectories • Designing complete VR experiences • Supporting learning

29. Further Information • www.mrl.nott.ac.uk • www.blasthoery.co.uk • www.thrilllaboratory.com • Papers and videos available at: www.mrl.nott.ac.uk/~sdb • Benford, Giannachi, Koleva & Rodden, ‘From Interaction to Trajectories: Designing Coherent Journeys Through User Experiences’, ACM CHI 2009 • Benford &Giannachi, ‘Temporal Trajectories in Shared Interactive Narratives’, ACM CHI 2008 • Benford et al, ‘The Frame of the Game’, ACM CHI 2006 • Reeves, Benford, O’Malley and Fraser, ‘Designing the Spectator Interface, ACM CHI 2005 • Gaver, Beaver & Benford, ‘The Role of Ambiguity in Interfac Design’, ACM CHI 2003