Guillaume Zufferey
The current trend in Human-Computer Interaction aims at bridging the gap between the digital and the real world, exploring novel ways to engage users with computational devices. Computers take new forms that are better integrated into our environment and can be embedded in buildings, furniture or clothes. Novel forms of interfaces take advantage of people's intuitive knowledge of everyday objects to offer more direct and natural interactions. Tangible User Interfaces (TUIs) allow users to interact with digital objects through tangible artifacts, building on their rich physical affordances. Paper User Interfaces (PUIs) add digital capabilities to paper documents, synchronizing for instance their content with their digital counterpart. Unique properties of paper are also used to create engaging and intuitive interfaces to computer applications. This dissertation is interested in the complementarity of tangible and paper interfaces in tabletop environments. We introduce the concept of Tangible and Paper Environments (TaPEs) where Interactive Paper Forms (IPFs), a particular type of PUIs based on the paper form metaphor, are used as a complementary interface to a TUI. We evaluate the potential of IPFs to overcome two main shortcomings of TUIs, in terms of scalability and pedagogy. The scalability issue comes from the limited expressiveness of task-specific physical artifacts, which offer rich physical affordances but limit the complexity of applications that can be controlled by a TUI. The pedagogy issue is raised by the lack of consistent evidence regarding the use of physical manipulatives in educational settings, which is one of the main application domain of TUIs. IPFs overcome the scalability issue by offering a set of generic interaction elements that allow TaPEs to cope with applications of any complexity. In a pedagogical setting, IPFs present learners with abstract representation which facilitate understanding by the embodied and concrete representations offered by tangible artifacts. A TaPE, the Tinker Environment, has been developed with two logistics teachers in the context of the Swiss vocational training system. It consists of a warehouse physical small-scale model (TUI) and TinkerSheets, our implementation of IPFs. It aims at helping apprentices understand theoretical concepts presented at schools. We followed a Design-based Research (DBR) approach: ten studies were conducted during the development of the Tinker Environment in authentic classroom settings. Controlled experiments were conducted to address specific questions. v The general research questions concern the respective affordances of paper and tangible components of TaPEs. The analysis is not limited to usability aspects but also considers their impact on group problem-solving activities and their potential in terms of integration of the system in its context of use. A descriptive model is proposed, built around three interaction circles: individual (usability), group (collaboration) and context (integration). Results identify design guidelines that limit the impact of the less direct interaction modality offered by IPFs, allowing TaPEs to overcome the scalability issue while supporting rich interactions. At the group level, observations of groups of apprentices solving problems around the Tinker Environment show that the consistent physical interaction modality offered by TaPEs naturally supports collaborative interactions. Apprentices tend to take implicit roles based on their location around the system. Regarding the context circle, we observed that carefully designed IPFs play the role of bridges between offline and online activities and contribute to a tight integration of the system in a its context (i.e. a classroom). The specific research questions address the potential of the Tinker Environment in this pedagogical context and its appropriation by teachers. The observations conducted with the Tinker Environment show that the warehouse small-scale model reduces the complexity of problems and allows apprentices to engage in meaningful problem-solving activities. Controlled experiments comparing a TUI to a mulitouch interface demonstrate that tangible artifacts lead to a higher learning gain and an increased performance in a problem-solving activity. Collaboration quality and perceived playfulness are also improved. The teacher plays a central role in the use of the environment, guiding apprentices through activities and encouraging reflections during debriefing sessions. The design of IPFs, emphasizing either their interface or document nature, has a strong influence on their ability to support teachers. We finally discuss the two-way adaptation process that took place between teachers and the system during the development of the Tinker Environment.
EPFL2010
