Understanding the Characteristics of Metaphors in Tangible User Interfaces

The idea of metaphors has been a central and popular element in the design practice of graphical user interfaces. While the principle is commonly applied and discussed in the field of Graphical User Interfaces, its usage in the field of Tangible User Interfaces (TUIs) is not yet fully understood. This paper analyses the principle of metaphors in TUIs, based on the main definitions of interface metaphors being discussed in literature. Our aim is to identify the characteristics describing a metaphor in TUIs and to propose a concept that can be used in TUI design activities. Using the example of the so-called “ColorTable”, we discuss how the principle of metaphor based on source and target can be applied to the particular context of TUIs. From our insights, we propose a concept of TUI metaphors which links the physical, the digital, and the application domain of TUIs.