System Dynamics for Modeling Metabolism Mechanisms for Urban Planning

Dynamic urban development simulation models are usually separate to urban planning tools making it difficult to test the consequences of urban planning variants directly without switching between expert tools. This paper presents an approach to integrating system dynamics simulation at various scales and abstractions in the visual programming environment Grasshopper for Rhino3D. We demonstrate how Grasshopper may be used with additional customized components as a flexible integrated urban planning and simulation framework. For this purpose, we present three urban planning model examples: The first is a classical system dynamics simulation that abstracts from spatial elements. The second adds spatial relations in terms of distances between locations in a grid. The third shows how to represent a city in more details and adds a network analysis module for more precise distance calculations. As result, we demonstrate a highly flexible approach for integrating simulations for various aspects that predict the behavior of an urban system in order to facilitate more sustainable urban planning processes. The main drawback of this new level of flexibility is the relatively slow execution time for complex simulations.