Bringing clay and sand into digital design - continuous tangible user interfaces

Tangible user interfaces (TUIs) provide physical form to digital information and computation, facilitating the direct manipulation of bits. Our goal in TUI development is to empower collaboration, learning, and decision-making by using digital technology and at the same time taking advantage of human abilities to grasp and manipulate physical objects and materials. This paper presents a new generation of TUIs that enable dynamic sculpting and computation and analysis using digitally augmented continuous physical materials. These new types of TUI, which we have termed 'Continuous TUIs', offer rapid form giving in combination with computational feedback. Two experimental systems and their applications in the domain of landscape architecture are discussed here, namely 'Illuminating Clay' and 'SandScape'. Our results suggest that by exploiting the physical properties of continuous soft materials such as clay and sand, it is possible to bridge the division between physical and digital forms and potentially to revolutionise the current design process.