Abstract. The consequences of architectural planning and design decisions made in the early design phases are hard to foresee. While professionals are used to reading plans and understanding architectural models, most laypeople are not familiar with their abstractions. This can lead to misinterpretations and misunderstandings between the different participants in the design process, especially in complex building situations, and decisions can be made or rejected that can have far-reaching consequences for the remainder of the project.In this paper we describe the concept and prototypical implementation of a decision-support system for the early design and discussion stages of urban design projects that aims to address precisely this problem. The setup directly connects physical volumetric models and hand-drawn sketches with an interactive, mixedreality visualization presented on a tablet or mobile phone, making it possible to see an interactive real-time view of an architectural design within the context of the actual site. In addition, the system is able to incorporate interactive simulations conducted on the model and presented in the AR-view.
Keywords: Early design stages · Urban design · HCI · Tangible interfaces · Immersive environment · Simulations
ProblemDuring the early design phases presentations and discussions between architects and clients usually involve sketches, paper and models. While designers are used to working intuitively with these tools, laypeople are not used to reading plans or scale models and find it difficult to relate these abstract representations to the real world. Many people, therefore, find it hard to assess the impact of design decisions at this stage for the later result.An alternative means of presentation is the use of perspective drawings and visualisations that show how an architectural design will look in a real scenario or the actual context. With the availability of affordable and ever more powerful computers, handdrawn perspectives have mostly been replaced by digital visualisations, initially in the form of individual rendered images and more recently in the form of immersive and © Springer-Verlag Berlin Heidelberg 2015 G.