Tangible Interfacing is an independent research field, which investigates into the benefits of combining real-world objects with algorithmic data handling. They therefore exploit real world objects for the manipulation of digital information. In other words, they enhance physical objects with digital functionality. What seems to be a rather simple idea eventually turns out to be a powerful approach to the conscious development of complex, yet natural interfaces.
The user experience of a Tangible Interface is dominated by the incorporated physical objects. Their inherent natural features of which users already have a prototypical concept are valuable for the designer and make it easy to develop interfaces that are naturally capable of collaborative and multi-handed usage. Even further, the usage of tangible objects implicitly incorporates a non-exclusive application, so the system designer does not have to explicitly implement it.
Although it is still possible to design uncomfortable systems, the users’ everyday knowledge on physical objects and the handling of these encourage a nature-inspired interface design, which makes Tangible Interfaces a strong tool for HCI. Another benefit arising from a carefully designed system is the implicit display of its inner state. It makes it possible to observe the augmented artefacts and their relation to each other. The input device turns into a bidirectional component that is both controller and display at the same time. All this supports the user’s development of a feeling of flow, just as it is common when playing a traditional musical instrument.
One rather utopical vision on how data and algorithmic functionality may be explored and handled in the future can be derived from Goldsworthy’s leaf sorting. Aspects that are worth imitating are the richness in the feedback and manipulation cues as well as the subtlety in its reactions. In this light, operating a Tangible Interface may not look different from manipulating non-augmented real-world objects for an external observer. The only difference to unaugmented artefacts, though, is the cause of its sonic, haptic and visual feedback, which is not only a result of pure physical reactions. Furthermore, it also derives from artificial reactions of algorithm-based changes in the data representation that is associated to the interface. In this case, it is not essential that the technical process is hidden, far more important is the fact that the human-computer interface is seamlessly integrated into the natural environment of its users.