Summary

City Information Modeling (CIM) has been pointed out as an extension of the Building Information Modeling (BIM) concept for urban space. Given the increasing urban complexity, interdisciplinary professionals who work with the city´s infrastructure require new resources to supply the needs on planning, design, construction, and management of the urban assets and the renewal of those. In this context, technologies, tools, systems and standards have been proposed to face the urban demand for new services, expansion or improvement thereof, to reduce costs and ensure quality standards. Among the resources available to urban demands are Geographic Information Systems (GIS), City Geography Markup Language (CityGML), tools for design, simulation, management, and more recently, appears CIM. However, thought CIM is increasingly present in the technical literature and at various forums, even the concept is not fully established. Seeking to contribute the explicitness of the CIM paradigm and fostering the discussion, this project combined three aspects that are essential for the design and implementation of CIM: 3D data capture (e.g. structure from motion approach, SfM), 3D data modelling (e.g. CityGML semantic and geometric approach), and 3D data management (e.g. PostGIS open geodatabase support). Based on a strong analogy with the BIM paradigm, and a complementary approach to the concept of Smart City, CIM is a promise for the future, since there are many open questions that range from conceptual, technological and operational aspects to political and economic issues. If the implementation of CIM represents a great challenge to be overcome in the next years, the challenges already posed by the cities in the 21st century are even greater. In spite of the development of CIM in a critical economic and uncertain environment, it raises many doubts about its feasibility or opportunity, issues such as the crisis of water, energy, and urban mobility, among others, place this discussion in a compelling position that should not be postponed. On the one hand the idea behind this project was to implement components for a CIM model prototype based on geometric data capture using geodetic and remote sensing methods such as laser scanning and Dense Stereo Matching (DSM) as a basic technique of SfM methods. On the other hand, the approach for modelling semantic information of the city model was focused on a combination of applying City Geographic Markup Language (CityGML), known as a data standard for 3D city models in the GIS context and Industry Foundation Classes (IFC), the data standard for Building Information Modeling (BIM). By this the German side (Remote Sensing / Geodesy / Geoinformatics) and the Brazil side (Architecture / Facility Management) have been complementing their know-how to come up with a cooperative research work. The results have been presented on workshops at Federal University of Bahia and at KIT as well as at international conferences as another “part of the puzzle” to reinforce the academic relations between Brazil and Germany.