The generation of 3D models through Terrestrial Laser Scanning has proved to be valuable tools for the study, documentation and recreation of archaeological remains. In this context, it is described how to generate a physical model to provide not only to researchers, but also as teaching material for teachers for university students, facilitating their access and study. As a practical case, this article describes the acquisition, processing and management of archaeological data in the archaeological site of Cástulo, Jaén, in South Spain. We expound how to get the 3D-printed model of the Muslim tower, showing how it is possible to generate a scale and very reliable reproduction of the structure, being also an useful and tangible material in the teaching of cultural heritage.

In recent years, the application of geomatics tools in archaeology has proved to be very useful to obtain meaningful knowledge of the 3D reconstruction of archaeological remains and semantic classification of the 3D surface. These techniques have proven to be an effective solution for the 3D modeling and the extraction of many spatial features on an archaeological site. However, novel methodologies as well as new data exploitation strategies are required to exploit these geospatial data for natural and cultural heritage documentation, monitoring, and preservation. In this paper, we have studied unique archaeological ruins, a Mozarab church in Al-Andalus, using high-resolution RGB images, which was taken by a drone. Thus, a 3D reconstruction of the ruins and the surrounding environment is carried out in order to characterize it on a dense point cloud. Then, a digital elevation model (DEM) was calculated in order to identify critical slope lines, which are significant to determine where the structure of the church was built. Our results can be used for the development of an architectural project and thus a virtual recreation of these archaeological ruins was performed.

The characterization of 3D vegetation structures is an important topic, which has been addressed by recent research in remote sensing. The forest inventory requires the proper extraction of accurate structural and functional features of individual trees. This paper presents a novel methodology to study the impact of the canopy reflectance on the 3D tree structure. A heterogeneous natural environment in a Mediterranean forest, in which various tree species (pine, oak and eucalyptus) coexist, was covered using a high-resolution digital camera and a multispectral sensor. These devices were mounted on an Unmanned Aerial Vehicle (UAV) in order to observe the tree architecture and the spectral reflectance at the same time. The Structure from Motion (SfM) method was applied to model the 3D structures using RGB images from the high-resolution camera. The geometric accuracy of the resulting point cloud was validated by georeferencing the study area through multiple ground control points (GCPs). Then, the point cloud was enriched with the reflected light in four narrow-bands (green, near-infrared, red and red-edge). Furthermore, the Normalized Difference Vegetation Index (NDVI) was calculated in order to measure the tree vigor. A comprehensive analysis based on structural and spectral features of individual trees was proposed. A spatial segmentation was developed to detect single-trees in a forest and for each one to identify the crown and trunk. Consequently, structural parameters were extracted, such as the tree height, the diameter at breast height (DBH) and the crown volume. The validation of these measurements was performed by field data, which were taken using a Total Station (TS). In addition, these characteristics were correlated with the mean reflectance in the tree canopy. Regarding the observed tree species, a statistical analysis was carried out to study the impact of reflectance on the 3D tree structure. By applying our method, a more detailed knowledge of forest dynamics can be gained and the impact of available solar irradiance on single-trees can be analyzed.

Problems of precision and accuracy in geographical information systems have often been undervalued. However, these are important issues when trying to avoid inaccurate computations that could distort the final result. A method is described for the Transverse Mercator Projection of the ellipsoid to calculate the necessary number of terms of their series development so that desired accuracy can be achieved. The first part describes one algorithm used to obtain the full development of the formulas by means of a symbolic calculus program. The second part studies the influence of each term in the final result in order to know which terms can be neglected while achieving the desired precision. Finally, the results are applied to a rectangle of 30° width and latitude varying from 30° to 50°.

Handheld LiDAR devices are revolutionizing 3D data capture, offering unprecedented accessibility and ease of use even for inexperienced users. These compact systems facilitate robust virtual reconstructions by extracting detailed geometric information from real-world environments. Advanced positioning systems in these devices generate highly accurate georeferenced 3D point clouds, enhancing the precision of scanned scenes. Leading manufacturers like FARO Technologies, Leica Geosystems, and Trimble offer diverse models, including the FARO Focus, Leica BLK360, and Trimble X7. These devices are invaluable in fields such as cultural heritage conservation, where they document and preserve historical sites; topographic mapping, providing accurate surveys in challenging terrains; and industrial inspection, ensuring thorough examinations of infrastructure and machinery. Additionally, the visualization of these 3D models on web platforms significantly enhances their accessibility and interaction. Web-based visualization tools allow users to explore, manipulate, and analyze 3D data from any location with an internet connection, democratizing access to detailed spatial information and enabling a broader range of users, from researchers to educators, to engage with complex datasets without the need for specialized software. Interactive features on these platforms, such as zooming, rotating, and measuring, provide an intuitive interface for detailed examination and collaboration. Consequently, the integration of handheld LiDAR technology with web visualization platforms opens new avenues for innovation and collaboration across various disciplines, further revolutionizing traditional methods and expanding the potential applications of 3D data capture.