Cálculo de la velocidad en el rotor y potencia del motor

Figure1.6: The conversational relationship between the mind and the sketch as represented by Buxton (2007b) and described by Goldschmidt (1991).

sign concepts. That means that they have limitations for externalizing and representing visions of interactions which unfold across time and space, and for sharing such visions with others. Thus, this thesis presents sketches of interactions and experience prototypes realized in different ways and with different levels of refinement, for different audiences and domains.

With respect to the design contribution to HCI, one can then conceive of design research as a discipline dealing with the creation of artifacts (sketches, experience prototypes, and probes) which can raise the understanding of a certain problem and can facilitate the communication among design stake- holders in iterative phases of problem setting and problem solving. In this sense, design research also promises to contribute to the identification of users’ benefits and identification of requirements through the creation of ar- tifacts which are open for users’ expression of needs and preferences. Such creative and iterative activities, which distinguish the design practice, are reflected in the approach adopted in this dissertation.

1.3

Approach

The approach that follows is explorative as well as empirical and can be described as consisting of three main activities: 1) Sketching interactions; 2) Reading sketches; 3) Comparing and assessing. These activities are described in the following paragrph.

1 Introduction

Figure 1.7: Examples of transitions across different levels of refinement of an idea for photo browsing on an interactive tabletop: a) Exploratory sketches with pen and paper; b) A tool made of cardboard representing a tangible UI: By placing it on a PC screen and taking a sequence of photos of different screen-shots, a storyboard of the interaction was created; c) The prototype implemented on an interactive tabletop.

1.3.1

Sketching Interactions, Prototyping Experiences

The sketching of interactions and the creation, reiteration and analysis of experience prototypes instantiating interaction design concepts has been the basis for the work presented in this thesis and the communication thereof. In this sense, referring again to Buxton’s (2007b) approach, this work presents “sketches of experiences”, which were refined to different levels (see Fig. 1.7) so as to share design concepts, reflect upon, and learn from them.

Starting from an identification of the different aspects of physical inter- action (cf. Fig. 1.3), and building on an analysis of how related work has integrated some of those in the design of hybrid ones, the design work here presented draws upon the consideration of physical artifacts, spaces, and in- teractions in a number of ways. First, analogue technologies are considered in

1.3. Approach

order to extrapolate some of the qualities thereof that characterize and affect human interactions and experiences; secondly, different aspects of physical- ity are metaphorically referenced or integrated in the design of experience prototypes for different types of domains (e.g., kitchen, design, and domes- tic environments) and different social contexts of use (e.g., simultaneous vs. asynchronous shared interactions). In doing so, those designs metaphorically reference physical artifacts at different levels of the interface design, from pragmatic to conceptual (cf. Chapter 2, Section 2.2), and exploit different aspects thereof as metaphorical sources: e.g., their manipulation vocabulary in the physical world, the way they are used in a social context, and the way they mediate interpersonal communication for utilitarian as well as decora- tive purposes (e.g., picture frames or mirrors on the home mantelpiece).

In such an approach, qualities of physical technologies are considered in the light of their potential for being coupled or augmented with digital ones so as to create meaningful hybrid experiences, which could extend humans’ communication, creativity, and self-expression possibilities. These should go beyond what is possible in the purely physical reality, but still build on an understanding of humans’ needs and values, and consciously exploit humans’ mental models of how things (physical and digital) work for them.

By evaluating those sketches, such values and mental models can be elicited or further understood, as discussed below.

1.3.2

Reading Sketches

Each design was evaluated in order to “read” the potential benefits of those interaction sketches and experience prototypes, as well as to learn from them. In this sense, those designs acted as probes and test-beds, i.e., research tools for validation as well as elicitation of design issues to be considered, and for leveraging an understanding of users’ expectations and mental models of hybrid interaction.

The methods that were used for assessment were diverse, mostly qualita- tive and applied in different settings due to the different technologies sup- porting their implementations. Whilst smaller devices such as tablets or graspable UIs were tested in situ (e.g., the Learning Cube, the Living Cook- book, and the Time-Mill Mirror), large and multi-display appliances (e.g., the Mug Metaphor Interface, the EnLighTable and Brainstorm) had to be tested in the lab because of the heftiness of the display hardware. Also in these latter settings, the trials were designed to be as plausible as possible, either in terms of target users, or in terms of tasks. This is because, as suggested by Hutchins (1995), the physical and social contexts of interaction

1 Introduction

affect users’ mental models of how the tools are supposed to be operated, their functionalities, as well as the users’ whole experience of use.

Therefore, when evaluating those designs, the focus was set both on the user interface at the pragmatic level and on the user experience provided by such prototypes. It was then taken into consideration whether or not (and how) users appropriated the manipulation vocabulary of the interface, and how this influenced their subjective assessment of the experience of use, thus trying to understand the link between interaction patterns and perception of experience.

1.3.3

Comparing and Assessing

The evaluation of the experience prototypes and their consideration in re- lation to other existing work suggested the identification of some critical issues for the design of hybrid interactions: These are mostly concerned with aspects of manipulation in 2D vs. 3D, and different aspects of tangibility.

To assess the relevance of those aspects and their design implications, two empirical studies in controlled experimental settings were conducted. In such comparative studies the critical variable was represented by the integration - or not - of some of the qualities of physical interaction (cf. Fig. 1.3) in the design of hybrid interfaces for direct input. The results indicate that despite the fact that several aspects of physical interaction are mimicked in the interface, the interaction with digital media is actually quite different. In this respect, the findings suggest that people’s previous experiences with the WIMP paradigm on the desktop PC affect their interaction behaviors and their expectations of functionalities and location of computing technologies, within the ecology of everyday life activities and socio-physical contexts. This fact provokes a reflection on users’ interaction attitudes, expectations and associated values for leisure, social technologies.