Certain historical works of civil engineering should be preserved as heritage monuments and when possible should continue serving the function they were designed for. Old stone bridges could be sustainably maintained but their conservation requires accurate documentation. In this study, we have scanned Ízbor bridge (1860) in Spain, and to facilitate conservation, we have modeled the ancient bridge using BIM (building information modeling). We propose a method and a model for this kind of bridge to be used as a reference for similar heritage monuments. Ízbor bridge modeled in this way will be useful for government planning and conservation agencies.

Cultural Heritage buildings face major challenges trying to combine a usability function with conservation and restoration obligations. Suitable conservation involves a complex set of activities, some concerned with historical documentation (functionality, construction materials, physical developments, etc.). Other activities require a geometrical description in order to detect pathologies related to walls tilting, displacements or roofs and beams deformation. Here, we propose a methodology that takes into account all those requirements when modeling a key 14th century Cultural Heritage building in Granada (Spain): Corral del Carbón. Known in the Moorish period as “Alhóndiga”, the building was used as an inn and a warehouse for merchandise. We survey the building with the most accurate techniques currently available (scanner laser and photogrammetry). After surveying it, we model the building at different levels of detail taking into account the various phases known to comprise the building. Finally, we propose an HBIM (Heritage Building Information Modeling) for building maintenance and facilitate its sustainability and usability over time.

Remote sensing is a useful tool for the documentation of archaeological sites. The products derived from a photogrammetric project applied to archaeology such as orthophotos and three-dimensional virtual reconstruction (3DVR), allow for detailed study of the Fuente Nueva 3 site in Orce. In our study of the Fuente Nueva 3 site in Orce, we used 3DVR intensively to map out the morphometric features of mammoth tusks exposed on the surface and a geological fault affecting the site’s deposits. To do so, we used imagery captured since 2017 in order to follow the evolution of ongoing excavations during each subsequent field season. We also integrated the 3DVR model in a videogame environment, to create a virtual reality (VR) that allows a VR navigation experience around the scenario using a head mounted display like Oculus Rift. The main features of this VR experience are: (1) It is ideal for the diffusion of archaeological contents since it permits an attractive presentation mode thanks to stereo visualization and realistic immersion sensations; (2) it provides a high level of detail all along the navigation experience, without incurring any damage to the archaeological remains; (3) it allows users to observe more details than they would in an in situ visit to the site; (4) it makes it possible to convert an archaeological site into portable heritage, opening up the possibility to extend visits to vulnerable groups: specifically those with reduced mobility. Our results show that using VR should permit enhancements to a visitor’s experience and contribute to the socio-economic development of the town of Orce, one of the Spanish municipalities with the lowest income.

In this paper, we describe and discuss emergent digital technologies employed for monitoring the excavations at the archaeological site of Barranco León (Granada, Spain) between 2017 and 2020. The method entails the following material requirements: a total station, a conventional camera, a computer and a software that integrates photogrammetry algorithms; in terms of human resources, the presence of an engineer for the first day of the excavation to set up the methodological process and trained excavation staff to perform said method on a daily basis is necessary. Here we present the daily workflow for monitoring archaeological excavations introduced at the site, followed by an estimation of the costs and a summary of the results obtained. The method introduced here is based on the height difference of Digital Elevation Models (DEMs) computed on successive days using photogrammetric techniques. It is a non-invasive method, which requires less than 8% of the economic resources of the excavation and can be carried out in less than 15 minutes. This allows the excavation director to have an accurate and visual idea of the excavation process in order to make appropriate decisions. In addition, from the results obtained in the method (differences in DEM of every two days), other derived results can be obtained such as the exact location of the archaeological remains extracted based on their size. These features highlight the relevance and applicability of this approach to a wide range of archaeological sites.

Point cloud (PC) generation from photogrammetry–remotely piloted aircraft systems (RPAS) at high spatial and temporal resolution and accuracy is of increasing importance for many applications. For several years, photogrammetry–RPAS has been used to recover civil engineering works such as digital elevation models (DEMs), triangle irregular networks (TINs), contour levels, orthophotographs, etc. This study analyzes the influence of variables involved in the accuracy of PC generation over asphalt shapes and determines the most influential variable based on the development of an artificial neural network (ANN) with patterns identified in the test flights. The input variables were those involved, and output was the three-dimension root mean square error (3D-RMSE) of the PC in each ground control point (GCP). The result of the study shows that the most influential variable over PC accuracy is the modulation transfer function 50 (MTF50). In addition, the study obtained an average 3D-RMSE of 1 cm. The results can be used by the scientific and civil engineering communities to consider MTF50 variables in obtaining images from RPAS cameras and to predict the accuracy of a PC over asphalt based on the ANN developed. Also, this ANN could be the beginning of a large database containing patterns from several cameras and lenses in the world market.

Sometimes it is necessary to know the transformation to apply to a mapping shape in order to locate its true place. Such an operation can be computed if a corresponding reference object exists and we can identify corresponding points in both shapes. Nevertheless our approach does not need to match any corresponding point beforehand. The method proposed defines a polygon in the frequency domain—two periodic functions are derived from a polygonal or polygon. According to the theory of elliptic Fourier descriptors those two periodic functions can be expressed by Fourier expansions. The transformation can be computed using the coefficients of the harmonics from the corresponding shapes without taking into account where each polygon vertex is placed in the spatial domain. The transformation parameters will be derived by a least squares approach. The geomatics and geosciences applications of this method go from photogrammetry, geographic information system, computer vision, to cadaster and real estates.