Mapping speditivo da sensori mobili per il controllo della conservazione dei valori paesaggistici del territorio. Quick mapping by mobile sensors for landscape values monitoring and conservation

Geomatics researches, applied to architecture and landscape, are becoming increasingly focused on development of innovation in survey techniques and digital data management. Quick techniques are sought, with a high level of automation and versatility, to support knowledge management and protection of cultural heritage, be it referred to artistic and architectural heritage or, overall, to whole varied landscape assets, in so such highest density in the country as to consider Heritage itself. The investigation and conservation initiatives in the field of landscape heritage must constantly deal with many conditions of risk exposure, and that is not always possible to make up with preventive protection, whether if it is a constant risk like that intrinsic to the status of the property, or sudden and unforeseen risks, or if it is only partially predictable, determined by an environmental emergency. In these test-sites, which have a typical vulnerability resulting from their intrinsic conditions of exposure to risk, is interesting to experiment and combine technological research with the public interest for the protection and preservation of the value of the asset. This paper is intended for the testing of systems for the expeditious acquisition of spatial data in a outstanding test site, an area of the Cinque Terre, devastated by the flood of autumn 2011 Le ricerche della Geomatica applicata all’Architettura e al paesaggio, sono mirati sempre più allo sviluppo dell’innovazione nel campo delle tecniche di acquisizione dei dati e della loro gestione digitale; si ricercano metodi speditivi, con elevati gradi di automazione e versatili, per il supporto alla gestione della conoscenza e della tutela del patrimonio culturale, che sia esso riferito ai beni artistico-architettonici o in senso più ampio all’insieme variegato dei beni paesaggistici, ad elevatissima densità nel territorio nazionale tanto da considerarlo Patrimonio esso stesso. Le indagini e le iniziative di conservazione in materia di patrimonio paesaggistico devono costantemente fronteggiare le innumerevoli condizioni di rischio cui esso è esposto, e cui non sempre si riesce a sopperire con una tutela preventiva. sia esso un rischio costante come quello intrinseco allo status del bene, oppure rischi improvvisi e imprevedibili, o solo parzialmente prevedibili, determinati da una emergenza ambientale. E’ in questi test-site, che possiedono una tipica vulnerabilità derivante dalle loro intrinseche condizioni di esposizione al rischio, che risulta interessante sperimentare e combinare la ricerca tecnologica con l’interesse collettivo di tutela e conservazione del valore del bene stesso. Il presente contributo ha per obiettivo la sperimentazione di sistemi speditivi di acquisizione dei dati spaziali in un test site d’eccezione, un’area delle Cinque Terre devastata dall’alluvione dell’autunno 2011

Point clouds by SLAM-based mobile mapping systems: accuracy and geometric content validation in multisensor survey and stand-alone acquisition

The paper provides some operative replies to evaluate the effectiveness and the critical issues of the simultaneous localisation and mapping (SLAM)-based mobile mapping system (MMS) called ZEB by GeoSLAM™ https://geoslam.com/technology/. In these last years, this type of handheld 3D mapping technology has increasingly developed the framework of portable solutions for close-range mapping systems that have mainly been devoted to mapping the indoor building spaces of enclosed or underground environments, such as forestry applications and tunnels or mines. The research introduces a set of test datasets related to the documentation of landscape contexts or the 3D modelling of architectural complexes. These datasets are used to validate the accuracy and informative content richness about ZEB point clouds in stand-alone solutions and in cases of combined applications of this technology with multisensor survey approaches. In detail, the proposed validation method follows the fulfilment of the endorsed approach by use of root mean square error (RMSE) evaluation and deviation analysis assessment of point clouds between SLAM-based data and 3D point cloud surfaces computed by more precise measurement methods to evaluate the accuracy of the proposed approach. Furthermore, this study specifies the suitable scale for possible handlings about these peculiar point clouds and uses the profile extraction method in addition to feature analyses such as corner and plane deviation analysis of architectural elements. Finally, because of the experiences reported in the literature and performed in this work, a possible reversal is suggested. If in the 2000s, most studies focused on intelligently reducing the light detection and ranging (LiDAR) point clouds where they presented redundant and not useful information, contrariwise, in this sense, the use of MMS methods is proposed to be firstly considered and then to increase the information only wherever needed with more accurate high-scale methods

Fostering Etruscan heritage with effective integration of UAV, TLS and SLAM-based methods

The paper has the main role of highlighting the advantages resulting from the combination of different 3D survey methods and how the approaches that involve data and methods fusion can be advantageous in cases where the environment in which one operates is particularly impervious and not very inclined to be faced with traditional solutions. UAV Photogrammetry, TLS and the innovative 3D scanning based on SLAM technology are combined for the investigation and the documentation of a suggestive landscape and archaeological park. The hand held SLAM based scanner, capable of generating the point cloud travelling among complex indoor and outdoor environments, detecting even small defined spaces, has proved its fundamental importance for the knowledge and reconstruction of the landscape of a particular category of ancient heritage: the necropolis of the caves of the Baratti e Populonia park, which lies in a suggestive scenario of rich and dense forest

TLS AND IMAGE-BASED ACQUISITION GEOMETRY FOR EVALUATING SURFACE CHARACTERIZATION

In the framework of cultural heritage documentation projects, it is very frequent the use of dense and detailed 3D models derived from range-based or image-based techniques. These reality-based models represent an effective and powerful solution to document the geometries, the surfaces and the characteristic of heritage assets. In fact, these technologies allow us to accurately describe the level of detail and the surface characterization of the materials, and also to provide precious support for the evaluation of the conservation status of the surveyed structures. In particular, the object studied in the presented research experience is the Morano sul Po arch (Morano sul Po, AL, Piedmont, Italy), a valuable example of an industrial archaeology asset. For the knowledge process of the arch, both LiDAR systems and photogrammetric strategies have been used, in order to properly document the geometry, the consistency of the material and the decays. The specific aim of the research presented in this paper is the evaluation of the advantages and the critical issues of using a telescopic pneumatic pole to raise the position of the scans from the ground and decrease the angle of incidence of the laser beam on the surveyed object. For this reason, the study also takes into consideration the use of mini UAVs and their flexibility to effectively acquire vertical surfaces even at elevated heights, comparing the density and the roughness of the derived model with the data obtainable by using TLS systems

WebGIS tools to disseminate archaeological landscape memory

This research works is providing digital tools for knowledge, fruition, communication and promotion of built heritage, in a framework of landscape heritage valorisation. The application could be placed in a framework of established methods within a field of study, increased in the recent years, aimed at promoting the integration of processing digital methods and information dissemination. The central aim of this work is to obtain and manage spatial information that can be helpful to represent and promote the peculiar features of the Archaeological Mine Park of San Silvestro, using proper acquiring techniques derived from Geomatics, regional data retrieved from the spatial data infrastructures and archaeological data. The use of innovative rapid mapping methods, the generation of orthophotos and DTMs-DEMs (Digital Terrain Model-Digital Elevation Model), the harmonization of different sources, scales and reference system data, the integration of datasets that synthesizes the studies and the excavation activities of the parks over the years, have provided a large spatially referenced archive that testifies the historical richness of the site. Those information, if communicated via WebGIS, can help to highlight the memory values of a territory. In addition to the opportunity to integrate multi-content and multi-source spatial data into a single platform, the Web-GIS project uses applications and solutions in order to promote the preservation of the memory of the territory and the historical identity of the place. It is widely known that reaching the valorisation of a cultural heritage is possible only establishing and organizing stable structure, resources and networks

UAV photogrammetry and thematic maps for environmental risk assessment in construction safety

The rapid diffusion of UAVs (Unmanned Aerial Vehicles) has played an important role in engineering and assisting a wide range of human activities, often replacing the non-equally cost effective traditional practices. Apart from the economic advantages, these innovative methodologies have found their maximum application in activities where the direct human intervention might be extremely risky or lead to loss of lives. One of the main aims of the EU Occupational Safety and Health (OSH) Strategic Framework 2014-2020 is to improve implementation of existing health and safety rules, putting in place effective and efficient risk prevention strategies. The easiness of flying COTS (Commercial Off-the-Shelf) UAVs and the quasi-automatic flight plan generation are currently key features for monitoring environmental risks in mid hazardous environments, and these platforms are nowadays widely employed, even by non-professional users, in those fields where an aircraft assessment was considered not economically sustainable in the recent past. For the above reasons, UAVs have been successfully used in construction safety planning applications, with particular reference to the evaluation of the risk factors connected to the site, i.e. the context conditions potentially interfering with the safe execution of the working tasks. In the presented research, UAV photogrammetry has been used as a methodology for the environmental risk assessment of the surrounding area of a construction site of hotel facilities, located in the north of Italy, in a place with a high hydrogeological risk. The intrinsic instability of these areas has been analysed, and the support offered by this innovative technology has been used, in combination with the existing geological and geotechnical cartography, for tackling or containing the risks of landslide and avalanches. The above analysis is functional to the adoption of precautions for the safety of the construction operators, which is mandatory according to the Italian Legislative Decree no. 81/2008 “Consolidated text on safety at work”, and the subsequent use of the building for the future users, after its completion. The capability of generating a DEM (Digital Elevation Model) of the terrain is a powerful support for large-scale quantitative estimation of volumes, while the possibility of recognizing suspicious terrain conditions can be useful for the early detection of very old or new (and so not already mapped) landslide or avalanches origin points. The above analysis might be shared with the involved professionals in online repositories, using a free and open source 3D model viewer, both for collecting raw data observations and for assisting the decision-making safety planning. The possible future outcomes and the concrete possibility of implementing these technologies in the already existing traditional practices will be then discussed, outlining strengths and weakness of the proposed methodology

HBIM MODELLING FOR AN HISTORICAL URBAN CENTRE

The research in the geospatial data structuring and formats interoperability direction is the crucial task for creating a 3D Geodatabase at the urban scale. Both geometric and semantic data structuring should be considered, mainly regarding the interoperability of objects and formats generated outside the geographical space. Current reflections on 3D database generation, based on geospatial data, are mostly related to visualisation issues and context-related application. The purposes and scale of representation according to LoDs require some reflections, particularly for the transmission of semantic information. This contribution adopts and develops the integration of some tools to derive object-oriented modelling in the HBIM environment, both at the urban and architectural scale, from point clouds obtained by UAV (Unmanned Aerial Vehicle) photogrammetry. One of the paper’s objectives is retracing the analysis phases of the point clouds acquired by UAV photogrammetry technique and their suitability for multiscale modelling. Starting from UAV clouds, through the optimisation and segmentation, the proposed workflow tries to trigger the modelling of the objects according to the LODs, comparing the one coming from CityGML and the one in use in the BIM community. The experimentation proposed is focused on the case study of the city of Norcia, which like many other historic centres spread over the territory of central Italy, was deeply damaged by the 2016-17 earthquake

3D MODELLING FROM UAV DATA IN HIERAPOLIS OF PHRIGIA (TK)

[EN] In areas of archaeological excavation with architectural complexes, the generation of 3D data and their spatial information updating can now benefit from UAV photogrammetry. This technique shows a very rapid development in many fields, as it provides effective results for high-resolution and detailed surfaces, adding to both quickness and suistainable costs, quite irrespective of the form and extension. That is very important in Documentation phases of Cultural Heritage. In the field of archaeological researches, the nadir view from low altitude has always been a preferential point of view, then the generation of very large-scale models and orthophotos is of great interest today, and it seems to promise high future developments. So the paper focuses on a workflow to obtain photogrammetrical products generation using eBee system, by Sensefly, of growing popularity in the scenario of survey techniques. The potential of outcomes is also given by the selected monumental case studies in the city of Hierapolis in Phrygian, on which the MAIER (Italian archaeological Mission of Hierapolis) operates from the 60s of the twentieth century. The variety and complexity of the buildings, as well as the height of their ruins offers numerous trouble spots that is interesting to deal. A particular attention on the accuracy of DSM (Digital Surface Model) will be evaluated and reported thanks to the GCPs (ground control points) that have been easily measured since these aerial photogrammetry experiences by UAV are the last of extensive previous metric surveys conducted in the recent past.Chiabrando, F.; D'andria, F.; Sammartano, G.; Spanò, A. (2016). 3D MODELLING FROM UAV DATA IN HIERAPOLIS OF PHRIGIA (TK). En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 347-349. https://doi.org/10.4995/arqueologica8.2015.3587OCS34734

REPORT ON THE DIGITAL RECONSTRUCTION OF THE 4TH CENTURY SUSA (WORK IN PROGRESS)

[EN] The reconstructive study of the urban arrangement of Susa in the fourth century arise from the intention to exploit some resources derived by local studies and survey activities fulfilled by innovative methods from which the modeling of architectural heritage (AH) and virtual reconstructions are derived. The digital Segusio presented in this paper is the result of intensive discussion and exchange of data and information shared among the urban landscape documentation activities, and systems of virtual models generation, able to provide the charm of an ancient landscape. The land survey has been accomplished using aerial and terrestrial acquisition systems, mainly using digital photogrammetry from UAV (Unmanned Aerial Vehicle) and terrestrial laser scanning. Results of both methods have been integrated to medium scale geographical data available from regional map repository and some processing and visualization supported by GIS (Geographical Information System) have been fulfilled. Then, starting from accurate and detailed DEM (digital elevation model) and from other architectural scale models concerning the ancient heritage, the modelling of the ancient scenery arose. The reconstruction of an ancient scene begins with an accurate account of all the evidences from the studies of materials and documentary sources. The analysis and representation of the territory, supervised with the tools of geographic data management, are therefore primarily a media of analysis, then of comparison and validation with other data. Only after these steps, the land and the built heritage models become tools of communication and education, which are the typical functions of the virtual reconstruction of ancient environments. The integration of the history of city with digital and multimedia resources will be offered to the public in the city museum housed in the restored castle of Maria Adelaide, which stands in the place where the acropolis of the city lay in ancient timesChiabrando, F.; Dezzani, L.; Prencipe, A.; Spanò, A. (2016). REPORT ON THE DIGITAL RECONSTRUCTION OF THE 4TH CENTURY SUSA (WORK IN PROGRESS). En 8th International congress on archaeology, computer graphics, cultural heritage and innovation. Editorial Universitat Politècnica de València. 354-357. https://doi.org/10.4995/arqueologica8.2015.3589OCS35435

MULTI-TEMPORAL IMAGES AND 3D DENSE MODELS FOR ARCHAEOLOGICAL SITE MONITORING IN HIERAPOLIS OF PHRYGIA (TR)

The archaeological areas are one of the fields in which the contribution of image-base and range-based Geomatics techniques were employed since long time and are now getting popular (Hadjimitsis et al. 2009; Campana 2017). In recent times, Remotely Piloted Aircraft Systems (RPAS), together with Terrestrial Laser Scanning (TLS) survey systems become more and more interesting to be studied in excavations sites for monitoring purposes and solving high detail data and large scale and comprehensive mapping matters both from terrestrial and aerial point of view. 3D information derived from different acquisition campaign and different sensors too, belonging to the same spatial system, can be integrated and create a multi-temporal and multi-scale database (Remondino, Rizzi 2010; Kersten, Lindstaedt 2012; Moussa, Abdel-Wahab, Fritsch 2012; Chiabrando et al. 2016; Farella et al. 2016). The contribution of multi-sensor acquisitions, as it is known from increasing scientific experiences, offers by now to archaeological studies the possibility to obtain a multi-temporal view of the site with restricted time windows, but it is interesting considering also the possibility of a valuable integration and contribution of older image-based documentation, already stored in archives. In a complex archaeological area as the one of Hierapolis of Phrygia in Pamukkale (TR), a very interesting site investigated since several tens of years by the MAIER – Italian Archaeological Mission of Hierapolis, the impressive excavations have required extensive and accurate large-scale survey and documentation projects. This paper will also show the evolution over time of 3D survey methods. In particular, the presented experiences regarding the documentation campaigns by Politecnico di Torino and Geomatics group concern many multi-temporal datasets that have been acquired by different subsequent campaigns in 1997, 1998, 2007, 2012, 2015, by employing various sensors following the evolution of the acquisition techniques offers by geomatics in the archaeological field surveys