Contemporary interactive environments in public spaces come in a variety of forms, and it appears difficult to categories them. They often emerge from different disciplines as the arts, architecture or design and their creators have no HCI specific background. Sometimes they are making unintended use of existing technologies and don’t apply to basic concepts of canonical HCI related interaction paradigms or principles. The researcher has selected the following examples out of a vast collection of different approaches for the reason to point out either a particular interaction paradigm, interaction principle, technical solution, interesting use of the senses, or thought provoking concept that might contradict or enlighten the generic approach to these media. Some of the examples shown suit more than one category.

The division among the unique categories might seem arbitrary in some cases, yet the aim was to avoid another one titled "mixes of the above". They serve as a tool for the start and originate from Prof. Joachim Sauter, UdK Berlin. There are also other ways of categorising art at public spaces [1].

Categories of interactive media in public spaces

Interactive environments in public spaces can be classified roughly into four different categories. Sometimes the distinction appears to be unclear, as a piece has attributes qualifying it for two or more categories, in these cases the dominant factors of the piece determine the selection. A fifth category labelled “mixes of the above” was thus avoided.

Interactive Objects & Installations

Interactive installations within an exhibition that allow one-to-one interaction with one as well as with several visitors at a given time. These interactive installations are integrated into the exhibition space as well as into the narrative of the exhibition. Their function might be to impart knowledge or a sensorial experience. Aside from the interaction between information and visitor, this type of installation element encourages visitors to communicate with one another. A well designed installation whose visitors have little affinity to interactive systems, invites them to observe other visitors interacting and enable them to become involved into the process of knowledge transfer and experience. The system evokes dialogue among its human participants but strictly speaking there is no true dialogue between system and participant ... we should regard this as action/re-action or interaction.

Screenbased Applications

Screen based applications engage users into an interactive exchange with the information by a screen or a mobile device. The one-to-one engagement of each user with the application is dominant here. Often these screen-based applications are positioned to be used before or after an exhibition. e.g. at a learning centre on location or via Internet/Cd-Rom/DVD at home. Furthermore there are mobile screen based devices such as handhelds, which function as navigation- and information-assistants within an exhibition. In some cases screen based devices may be found in the exhibition itself yet only if there is a clear relation between the device and the concerned showpiece or artefact.

Interactive Spaces & Environments

Interactive environments are spaces where the interactive media determine the space and its behaviour. For example, Interactive floors and walls, allow the immersive and reactive change of the space according to the visitors behaviours. Such interactive spaces are usually multiple user environments where varying numbers of visitors may have shared experiences. Visitors should achieve equal grades of interactions with other visitors as well as experiencing the content.

Interactive Architecture

Interactive architecture usually is limited to actions upon the facade because of the costs (interactive facades) and usually they bear their effects during night time. Dynamic actions (dynamic, participative interactive lightstages or projections) on the façade may lead to a higher identification of (potential) visitors and employees of the building e.g. a museum. The building is highlighted among its urban context. Aside light installations such as projections; there have been a few examples of material or dynamic facades and first dynamic architectures in the recent years.

[1]John Marshall, √2, pointed me to catagories for art at public places by Paul Swales which are the aesthetic, the didactic, the symbolic and the functional.