Rafael E. Hidalgo-Fernández

Bio: Rafael E. Hidalgo-Fernández is an academic researcher from University of Córdoba (Spain). The author has contributed to research in topics: Natural heritage & Virtual archaeology. The author has co-authored 4 publications.

Digitalization and 3D Documentation Techniques Applied to Two Pieces of Visigothic Sculptural Heritage in Merida Through Structured Light Scanning

Abstract: Technological advancements have a great impact on the dissemination and understanding of the cultural heritage reality due to innovative techniques. These innovations are based on high-precision and high-resolution technologies that allow for the geometric documentation of any object within the fields of history and the arts. Through these techniques, new proposals may be studied and objects can be placed in any historical context. Three-dimensional (3D) digitization allows one to obtain a digital 3D model, which can be handled virtually and recreated at any historical period, enabling the conservation and safeguarding of cultural heritage. Society currently demands new visualization techniques that allow interacting with architectural and artistic heritage, which have been applied in numerous virtual reconstructions of historical sites or singular archaeological pieces. This project allowed us to geometrically document a reused piece with two surfaces (shield and columns) and a plaque of the city of Merida using a structured light scanner from a theoretical-practical perspective. The 3D virtual reconstruction of the pieces was accomplished within this study. The generation of QR codes enabled the interactive display of the heritage pieces. Likewise, a proposal was made to reuse the aforementioned pieces through virtual archaeology. The initial hypothesis is based on the possible existence of a Visigothic niche as an original form. This research reports significant advances in the conservation and exploitation of cultural heritage.

Low-Cost Prototype to Automate the 3D Digitization of Pieces: An Application Example and Comparison.

Abstract: This work is aimed at describing the design of a mechanical and programmable 3D capturing system to be used by either 3D scanner or DSLR camera through photogrammetry Both methods are widely used in diverse areas, from engineering, architecture or archaeology, up to the field of medicine; but they also entail certain disadvantages, such as the high costs of certain equipment, such as scanners with some precision, and the need to resort to specialized operatives, among others The purpose of this design is to create a robust, precise and cost-effective system that improves the limitations of the present equipment on the market, such as robotic arms or rotary tables For this reason, a preliminary study has been conducted to analyse the needs of improvement, later, we have focused on the 3D design and prototyping For its construction, there have been used the FDM additive technology and structural components that are easy to find in the market With regards to electronic components, basic electronics and Arduino-based 3D printers firmware have been selected For system testing, the capture equipment consists of a Spider Artec 3D Scanner and a Nikon 5100 SLR Camera Finally, 3D models have been developed by comparing the 3D meshes obtained by the two methods, obtaining satisfactory results

Parameterisation and Optimisation of a Hand-Rake Sweeper: Application in Olive Picking

Abstract: Olive picking is one of the most common social agricultural activities in many regions of Andalusia where the predominant crop is the traditional olive grove. The machinery used includes shakers, blowers and an essential low-cost type: hand-rake sweepers. The latter are generally used by the women of the squads to sweep the olives that fall from the trees. This article is focused on the design and optimisation of a hand-rake sweeper, in terms of durability and cost, for the picking of olives and other fruits, such as almonds, which are currently the main alternative to nonperennial crops in Andalusia. A parametric design of a hand-rake sweeper was created for this application using the design software CATIA, and its most vulnerable points were analysed in terms of effectiveness with varying design parameters, conducting usage simulations with ANSYS for a light material such as polypropylene. The maximum von Mises stress of the whole structure was 155.81 MPa. Using ANSYS, the dimension parameters of the hand-rake sweeper structure were optimised. The modified design was analysed again, showing a reduction of maximum tensions of 10.06%, as well as a decrease in its maximum elongations (0.0181 mm).

Approach to the economic value generated in the natural parks of cordoba (spain)

Abstract: The economic valuation of the protected natural parks contributes to a holistic approach of the economy, from the market to the ecological and social perspective, aiming at a sustainable management of the natural heritage as well as reducing its deterioration. It also provides valuable information to policy makers for the protection and conservation of the natural environment. To estimate the recreational use value of the natural parks we applied a revealed preference method and a declared preference method. The results are consistent with previous studies on these types of protected areas.

Graphic representation of the degree of historical-archaeological evidence: the 3D reconstruction of the “Baker’s House”

Abstract: Abstract Over the years, the methodologies used for graphic representation in archaeology have evolved. The substantial change in representation was achieved with the use of computer software. Currently, 3D sketch scanning and photogrammetry are predominating tools used in this field. A new methodology, i.e., the use of the historical-archaeological evidence level scale, has entered this discipline to show the veracity of archaeological studies, as well as that of the vestiges found. The present study is focused on the virtual reconstruction of the ‘Baker’s House’ in the archaeological site of Torreparedones (Córdoba, Spain). The main aim of this study was to show and identify the veracity of the obtained reconstruction, through the use of the historical-archaeological evidence scale and the elaboration of a typological rank. The methodology used shows the evidence level employed by experts in the creation of virtual representations. The dissemination of the proposed historical-archaeological evidence scale entails the graphical identification of the veracity of reconstructions in this type of representations, always complying with the scientific quality criteria established by the Seville Letter.

Canvas Painting Analysis Using Spectroscopic Analysis and Microcharacterisation Techniques

Abstract: Raman spectroscopy is a well-recognised tool for the analysis of materials in canvas paintings. However, it can be difficult to interpret the peaks of the spectra without the additional context of the artwork such as the age, provenance, or colour. Reflectance spectrophotometry can be used to capture the colour of pigments, dyes, and lacquers, but is seldom used to complement Raman data. Additionally, reflectance spectrophotometry results can be influenced by the surface profile of the painting. To overcome these limitations, this work brings together three different analysis modalities to provide a singular, analytical map of the artwork. Raman spectroscopy was used to conduct the chemical identification of pigments, binding media, and varnish present in a synthetic painting sample. Reflectance spectrophotometry was applied to obtain colour information of the surface paint of the sample. Three-dimensional optical profilometry data was used to characterise the micro topology of the paint surface. These three data sets were spatially matched allowing the recorded spectroscopic data to be displayed with the corresponding colour and surface topography across the paint surface.

Fields Touched by Digitalization: Analysis of Scientific Activity in Scopus

Abstract: This study aims to analyze the publications in Scopus around digitalization in the space of time between 2018 and 2022. A bibliometric review is carried out with a bibliographic approach for 658 documents, which were processed by RStudio and VOSviewer software. The findings show the ten fields where digitization is most applied: “Archives, Corruption and Economy”, “Industry 4.0, Internet of Things, Sustainability and Big Data”, “Cultural Heritage, Deep Learning, Preservation and BIM”, “Photogrammetry and 3D Digitalization”, “Artificial Intelligence (AI) and Supply Chain Management”, “Augmented Reality, Machine Learning and Virtual Reality”, “Innovation, Business Model and Publishing Industry”, “Algorithms, E-government and Biometrics”, “Digital Collections” and “Healthcare”. It should be noted that this document is based on 88.14% original studies, validating the results obtained, and it is also one of the most updated studies.

Fatigue Analysis of Spike Segment of Special Tractor Wheels in Terms of Design Improvement for Chernozem Soil

Abstract: The driving wheels affect the tractive efficiency, fuel consumption, and soil compaction. This study presents the fatigue analysis of a spike segment that is the main part of an innovative driving wheels designed to improve tractor tractive performance. The design improvement was proposed for Chernozem soil allowing the full penetration of spikes. The spike segment was loaded by forces resulting from the maximum drawbar pull at 100% wheel slip and penetrometer resistance. A drawbar pull increase caused by the spike tires was also calculated. The experiments were performed using a subcompact tractor in the first gear on a grass field at soil moisture 18.8%. Gerber theory was used for the fatigue analysis performed using ANSYS software. The dependances of the safety factor on the horizontal rod diameter and the number of load cycles was constructed. The safety factor of 1.73 calculated for the spike segment made of steel S355 is suitable for the reduction of the actual horizontal rod diameter (12 mm). The fatigue analysis showed a safety factor of 1.28 at 100,000 load cycles in the case of a reduced diameter (10 mm). A diameter of 8 mm was also simulated, but the calculated safety factors do not allow it in terms of safe operation.