The classification process

3.1.3. The classification process

For the development of the catalogue a long iterative process has taken place, in which the catalogue structure, the categories and the subcategories, have been refined as more projects were added to the analysis and as a better understanding of the reality was gained. Whilst a detailed description of the process can be overlooked for the sake of simplicity, it is anyway important to shed light on some major restructuring steps that have taken place during the analysis.

In the first phase, the various collected projects have been analysed with the support of a spreadsheet that allowed to record categories and subcategories emerging during the analysis as well as to record and show how the various projects fell in these categories. (Figure 28).

Figure 28 Part of the classification table as emerged during the initial analysis of the collected projects.

Some drawbacks of this approach emerged soon and, with it, the necessity of thinking of a different structure for the data. The major flaw of this approach was that it put all the projects on a same level, considering them as similar and comparable entities, while in reality they did not in several cases. Indeed, some projects proved to be made of single interactive stations while others were made of more interactive stations more or less integrated between them. In addition, a single interactive station could encompass several different tangible user interfaces with different characteristics and behaviours that needed to be analysed separately. Besides, some of the categories being developed were more logically related to sub-components of the installation rather than to the overall installation. Finally, the way data was organized did not facilitate data retrieval, exploration and analysis.

What was needed was a model of representation of reality that embraced this complexity, and that allowed to consider and analyse the different entities that make up a tangible interaction installation and their inter-relations. In other words, a structure that took into account the different levels of granularity in which a tangible interactive installation can be analysed was needed.

Useful tools for representing inter-relations between entities in a given domain of knowledge come from computer science and are the Unified Modeling Language diagrams (UML diagrams) and the Entity-Relationships diagrams (E-R diagrams). They allow for an abstract representation of reality allowing to represent things of interest and the relationships existing between them (conceptual data modelling). An important advantage of using these diagrams is that through a simple operation (logical data modelling) they can be easily translated into a structure to be implemented as a relational database, in this way facilitating further data retrieval, data analysis and sharing.

In Figure 29 a UML diagram³⁶ representing the reality of tangible interaction systems developed for museums is shown.

36 The UML notation has been chosen for greater familiarity but could be translated easily in a E-R model by changing the notation.

Figure 29 UML diagram representing the reality of tangible interaction systems in museums.

The diagram identifies seven main entities that are:

- Installation: it is the biggest unit of analysis and represents a tangible interaction installation. As shown in the diagram an installation can be made up of one or more interactive stations³⁷.

- Station: it is a single “point of interest” in a tangible interactive installation (where other stations might also be present).

Although it happens sometimes that similar - if not identical from a technological point of view - stations can be found instantiated in different installations/places, it has been decided to consider them as different stations, as different will be the location, the relation with the environments, with the exhibited objects etc. For this reason, a certain station is associated to only one installation. A certain station refers to one or more CH assets, and supports one or more tasks.

37 It is important to notice that some ambiguity can raise when trying to discern between installations and stations, in the case of more interactive systems located in the same place. Must these systems be considered as separate single-station installations or as stations belonging to the same installation? While it is impossible to set objective criteria, in this thesis it has been decided to consider as belonging to the same installation those stations that present an integration that goes beyond the purely thematic one or the fact of belonging to the same place.

In addition, in the case of identical installations installed in different places or exhibitions, it has been decided to consider them as different and as such needing to be analysed separately. Indeed, the concept of installation is considered as something that goes beyond the pure technological aspect, and that is instead strictly linked to the concept of environment. On the light of that, two identical technological installations placed in different environments are to be considered as different.

Even more so, two installations that are similar from a technological point of view but are referred to different cultural heritage objects have to be considered as different and analysed separately.

- CH asset: it refers to a CH asset one or more interactive stations refers to. It can be tangible (an artefact, a work of art, a monument, a building etc..) or intangible (a story, an interpretation, an oral poetry etc.). The same CH asset can serve as a reference for multiple interactive stations.

- Task: it is a high-level objective or activity the system allows the visitor to achieve or accomplish. It can be decomposed in sub-tasks. High-level objectives/activities refer to the general goals/activities (the “what”) the user wants to reach or accomplish (e.g. get a story about an exhibited object) but not to how these are physically reached at the level of the interface.

A task is materially accomplished by the visitor by carrying out one or more actions in a specific interface (e.g. touching a sensitive area of an object or approaching an object are two possible different actions the visitor might be asked to carry out in order to get a story about an object).

- Action: it refers to a physical action that needs to be carried out as part of a task the user wants to accomplish. A specific action is linked to one specific task but more actions are needed in order to accomplish a task. An action always involves the presence of one or more interactive devices, although not always a contact with it is required.

- Device: it refers to the device the person interacts with through touch, gestures or manipulation, or the device where the output is provided. It can be a traditional input/output device (a touchscreen, a mobile device, a keyboard, a mouse, a joystick, a computer screen) or it can acquire the appearance of a more traditional low-tech object (smart object). The same device can be associated to more than one action, since different actions can make use of the same object. Likely, the same device can be used as output device for different outputs.

- Output: It refers to the feedback provided by the system to the visitors in response to specific inputs. It can be the result of a simple input action the user has carried out using the system, or it can be the results of the accomplishment of a more complex activity (requiring more actions) which implements a task. For this reason, in the diagram the “output” has been connected both to “action” and “task”. The output is always associated to a device that allows it to take place in reality.

In the following diagram (Figure 30) the entities or classes illustrated above have been detailed with the addition of some properties that characterize them. It is important to notice that while some properties have been filled out directly by examining the characteristics of the specific entity they belong to, the value of some other properties have been determined by examining the co-presence of several properties in different interrelated entities.

Figure 30 UML diagram representing the reality of tangible interaction systems in museums, showing entities and properties.

The representation model provided above allows for the examination of the projects under different perspectives, helping to answer questions, facilitating the process of discovery and the classification of

projects according to several aspects. The related database has been implemented using Microsoft Access³⁸.

A description of aspects and categories is provided in three different sections in the following pages:

• In the first section, some general observations about the project are presented (types, locations, targets, developers, etc.);

• The second section provides reflections related to the CH asset(s) enhanced by the interactive installation (types of assets, location of the asset with respect to the installation, etc.);

• The third section presents reflections related to the various elements that characterize the interactivity in the installations (like tasks, actions, interaction devices, smart objects, output).

In many cases, aspects and categories will be exemplified by referring to specific projects. Since a same project could be illustrative of more qualitative methodology, during the description and discussion of the aspects and categories, results of quantitative analyses are sometimes presented. Quantitative analyses have been developed using descriptive statistics in order to quantify the presence in the corpus of characteristics identified qualitatively in the data and considered particularly relevant or suitable for this kind of analysis. The results of these analysis might be useful for the identification of some of the areas that might benefit from future research.

38 At the moment, the database is not publicly accessible. Indeed, in the context of this research the main reason why it was created was to support the author during the analysis of the projects. However, since the database might be useful for other people working in the field, future works might regard its improvement and the implementation of its accessibility online. In addition, the database itself might benefit from its presence online by allowing the contribution from other people.

3.2 General information about the projects 3.2.1. Type of projects, years of creation

The collection includes projects coming both from academic and non-academic activities. The number of non-academic projects is 55 while the number of non-academic projects is 13. It is likely that being tangible interaction quite a new field, it is still mainly a research topic that has to find a concrete and diffuse application in reality. However, the way the projects have been collected does not allow to state anything with certainty regarding this difference in number. The graph (Figure 31) shows the distribution per year of the research projects in the collection.

The graph shows a positive trend in the number of academic projects developed per year, allowing to state that this field is expanding more and more.

Figure 31 Distribution per year of academic and non-academic projects (colour illustration at the end of the volume).