The role of urban designers is to shape the physical features of a city with the goal of making the city functional and pleasant to live in. For this, the urban designer has to gather information about the current situation, design improvements, and communicate these to stakeholders. The use of space and the spatial relationships between physical features play a significant role in urban design, therefore much of the information that is collected and manipulated is georeferenced. In this paper we review and evaluate open source geospatial technologies that can be used for the collection, storage, manipulation and visualization of geospatial data in urban design projects. Based on this, an open geospatial toolbox for urban design projects is presented.

We followed a scenario-based approach for collecting the requirements. Three researchers were asked to explain how they collect and use data for their urban design projects. Their backgrounds were in spatial planning and architecture. The first scenario involves an urban designer who is requested to guide and advise the local municipality on improvements in a neighborhood that has become dilapidated over time, and therefore unsafe. In the second scenario, the aim was to identify crime hotspots in a neighborhood and to propose preventative crime measures through environmental design.

By analyzing the scenarios, we determined both functional and non-functional requirements, and categorized them into requirements related to data collection, data storage and management, and data visualisation respectively. A set of open source geospatial technologies were evaluated against these requirements. Tools were evaluated against requirements relevant to a category, e.g. for data storage and management, the user should be able to upload geospatial data, upload newer versions of the data, create and edit metadata about the data, and share the data in various formats using web services. Furthermore, the evaluation results show how tools meet individual requirements, i.e. tools that meet only one of several requirements were not excluded. The resulting open geospatial toolbox is modular, allowing urban designers to swap out a tool in a category for another one in that category, or swap out a tool that meets one requirement for another tool that meets that requirement.

Each of the evaluated tools fulfilled the functional requirements to some degree; the real difference emerged from the non-functional requirements, such as perceived usability for novice users and documentation or support available. The results in this paper are based on requirements of urban designers, but are equally applicable for others who collect data at the neighbourhood level. Future work will focus on aspects of provenance for preserving and making data collected for urban design studies available for longitudinal studies.