A Rapid pipeline for periodic inspection and maintenance of architectural surfaces

The contribution fits into the framework of Digital Heritage, within the diagnostic process, leading up to restoration. Control and monitoring of architectural heritage are still open topics, with respect to requirements as simplicity, non-invasiveness and cost-effectiveness of both procedures and equipment. A peculiar gap concerns the accessibility to the artefact, which could be compromised by bad state of preservation, poor hygienic/sanitary conditions, or unsafe post-emergency circumstances, as well as by considerable extent, complex morphology, or incidental access conditions, due to the simultaneous presence of multiple working groups. In recent years, literature is moving towards an optimization of the investigation phases, by implementing digital technologies for the acquisition, elaboration and interpretation of 2D/3D data, to assess the state of conservation of a building or its main components. Besides, digital image processing and artificial intelligence are progressively rationalizing the analysis of the collected data. Furthermore, easy common devices, like spherical cameras or smartphones, have been introduced for the virtual reconstruction and representation of architectural environments, with the purpose of assessing their morphology and conditions. However, there is still an absence of harmonized standard procedures. To address these issues, the paper proposes a rapid pipeline, involving easy-to-use devices and expeditious procedures, to remotely assess, quantify, and monitor the extension of surface decay of historical buildings. A workflow based on the use of 360° images and videogrammetry has been defined and tested on a representative case study, both for its cultural value and for its limited accessibility, demonstrating a great suitability to the topic.