Comparison of Multi-Source Data, Integrated Survey for Complex Architecture Documentation

Abstract. The metric documentation of architectural complexes requires today the use of several integrated survey methodologies. This need is an answer to the morphology of the object such as dimension, geometry, inaccessible areas and urban context. These properties inhibit the use of single surveying techniques and force the integration of Geomatics tools. In addition, the metric documentation of Cultural heritage objects not always requires uniform accuracy and resolution, therefore the integration of different surveying methodologies and techniques become the only effective solution both from a technical and economic point of view. The integration, that is today adopted as normal strategy, allows also the better understanding of the benefits which can arise to speed up the metric documentation of Cultural Heritage objects and the benefits that each of the possible surveying techniques can have thanks to the integration of the different potentialities. This study starting from an integrated survey, performed whit a combined use of Mobile Mapping System (MMS), Unmanned Aerial Vehicles (UAV) and Terrestrial Laser Scanner (TLS) and show the results of the comparisons between the possible achievable accuracies by using a correct integration between the different used technologies and the ones achievable by using the same techniques as independent tools.The case study is the architectural complex of the Ducal Palace in Gubbio (Italy), located upstream of the most important town square facing the cathedral in a very complex but realistic urban context.