The monitoring of burned areas can easily be performed using satellite multispectral images: several indices are available in the literature for highlighting the differences between healthy vegetation areas and burned areas, in consideration of their different signatures. However, these indices may have limitations determined, for example, by the presence of clouds or water bodies that produce false alarms. To avoid these inaccuracies and optimize the results, this work proposes a new index for detecting burned areas named Normalized Burn Ratio Plus (NBR+), based on the involvement of Sentinel-2 bands. The efficiency of this index is verified by comparing it with five other existing indices, all applied on an area with a surface of about 500 km² and covering the north-eastern part of Sicily (Italy). To achieve this aim, both a uni-temporal approach (single date image) and a bi-temporal approach (two date images) are adopted. The maximum likelihood classifier (MLC) is applied to each resulting index map to define the threshold separating burned pixels from non-burned ones. To evaluate the efficiency of the indices, confusion matrices are constructed and compared with each other. The NBR+ shows excellent results, especially because it excludes a large part of the areas incorrectly classified as burned by other indices, despite being clouds or water bodies.

The mission planning in airborne Photogrammetry and Remote Sensing applications, depending on the system of acquisition and by the adopted platform (such as rotary and fixed wing aircrafts, glider, airship, manned or unmanned), is the first and essential step to ensure the success of a survey mission. The purpose of this paper is to provide an overview on mission planning techniques using passive optical sensors. The basic concepts related to the usage of the most common sensor technologies are described, along with the several possible scenarios that may be afforded by using modern airborne sensors. Several examples of flight plans are illustrated and discussed to highlight correct methods, procedures and tools for data acquisition in the case of different types of manned and unmanned airborne missions. In particular, the flight planning with more recent technologies of digital passive optical airborne sensors will be dealt with, including frame cameras and multi-/hyperspectral push-broom sensors. Furthermore, in order to ensure the complete success of an airborne mission, some up-to-date solutions to know in advance the weather conditions (cloud cover, height of the sun, wind, etc.) and the GNSS satellite configuration are illustrated.

The aim of this work is to identify an efficient pipeline in order to build HBIM (heritage building information modelling) and create digital models to be used in structural analysis. To build accurate 3D models it is first necessary to perform a geomatics survey. This means performing a survey with active or passive sensors and, subsequently, accomplishing adequate post-processing of the data. In this way, it is possible to obtain a 3D point cloud of the structure under investigation. The next step, known as “scan-to-BIM (building information modelling)”, has led to the creation of an appropriate methodology that involved the use of Rhinoceros software and a few tools developed within this environment. Once the 3D model is obtained, the last step is the implementation of the structure in FEM (finite element method) and/or in HBIM software. In this paper, two case studies involving structures belonging to the cultural heritage (CH) environment are analysed: a historical church and a masonry bridge. In particular, for both case studies, the different phases were described involving the construction of the point cloud and, subsequently, the construction of a 3D model. This model is suitable both for structural analysis and for the parameterization of rheological and geometric information of each single element of the structure.

In recent years, structure from motion (SfM) and multi-view stereo (MVS) algorithms have been successfully applied to stereo images generated by cameras mounted on unmanned aerial vehicle (UAV) platforms to build 3D models. Indeed, the approach based on the combination of SfM-MVS and UAV-generated images allows for cost-effective acquisition, fast and automated processing, and detailed and accurate reconstruction of 3D models. As a consequence, this approach has become very popular for representation, management, and conservation in the field of cultural heritage (CH). Therefore, this review paper discusses the use of UAV photogrammetry in CH environments with a focus on state of the art trends and best practices in image acquisition technologies and 3D model-building software. In particular, this paper intends to emphasise the different techniques of image acquisition and processing in relation to the different platforms and navigation systems available, as well as to analyse and deepen the aspects of 3D reconstruction that efficiently describe the entire photogrammetric process, providing further insights for new applications in different fields, such as structural engineering and conservation and maintenance restoration of sites and structures belonging to the CH field.

The management of Cultural Heritage (CH) requires increasingly efficient, simple and shareable tools, methods and knowledge. In this environment, a suitable procedure was developed to transform the point cloud, generated by geomatics surveys, into parameterized objects. In order to obtain an object with precise geometric and physical characteristics, a three-dimensional modelling software (Rhinoceros) was used. This software, using the tools and specific plugins, has allowed the parameterization of objects. In particular, the use of the Grasshopper plugin allowed a two-way transformation of the objects between the modelling software and the BIM software (Revit). As a result, any changes to the model made in Rhinoceros were automatically made in Revit and vice versa. The paper shows the potentiality, simplicity and efficiency of the developed method in order to perform the scan-to-HBIM process. This approach was applied to a religious building, located in Italy, belonging to the Cultural Heritage.