Recently, Fused Filament Fabrication (FFF), one of the most encouraging additive manufacturing (AM) techniques, has fascinated great attention. Although FFF is growing into a manufacturing device with considerable technological and material innovations, there still is a challenge to convert FFF-printed prototypes into functional objects for industrial applications. Polymer components manufactured by FFF process possess, in fact, low and anisotropic mechanical properties, compared to the same parts, obtained by using traditional building methods. The poor mechanical properties of the FFF-printed objects could be attributed to the weak interlayer bond interface that develops during the layer deposition process and to the commercial thermoplastic materials used. In order to increase the final properties of the 3D printed models, several polymer-based composites and nanocomposites have been proposed for FFF process. However, even if the mechanical properties greatly increase, these materials are not all biodegradable. Consequently, their waste disposal represents an important issue that needs an urgent solution. Several scientific researchers have therefore moved towards the development of natural or recyclable materials for FFF techniques. This review details current progress on innovative green materials for FFF, referring to all kinds of possible industrial applications, and in particular to the field of Cultural Heritage.

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A Review of Polymer-Based Materials for Fused Filament Fabrication (FFF): Focus on Sustainability and Recycled Materials

Multiple scattering and absorption limit the depth at which biological tissues can be imaged with light. In thick unlabeled specimens, multiple scattering randomizes the phase of the field and absorption attenuates light that travels long optical paths. These obstacles limit the performance of transmission imaging. To mitigate these challenges, we developed an epi-illumination gradient light interference microscope (epi-GLIM) as a label-free phase imaging modality applicable to bulk or opaque samples. Epi-GLIM enables studying turbid structures that are hundreds of microns thick and otherwise opaque to transmitted light. We demonstrate this approach with a variety of man-made and biological samples that are incompatible with imaging in a transmission geometry: semiconductors wafers, specimens on opaque and birefringent substrates, cells in microplates, and bulk tissues. We demonstrate that the epi-GLIM data can be used to solve the inverse scattering problem and reconstruct the tomography of single cells and model organisms. Quantitative phase imaging techniques have been limited by multiple scattering of light or its use in transmission mode. Here, the authors show a gradient light interference microscopy method in a reflection geometry which allows for label-free phase imaging of bulk and opaque samples.

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Epi-illumination gradient light interference microscopy for imaging opaque structures.

Historic Building Information Modelling (HBIM) is the most effective method of rebuilding virtual 3D models of heritage buildings, and constitutes a new information management system in the field o...

Combination of nadiral and oblique UAV photogrammetry and HBIM for the virtual reconstruction of cultural heritage. Case study of Cortijo del Fraile in Níjar, Almería (Spain)

This book presents interdisciplinary approaches to the examination and documentation of material cultural heritage, using non-invasive spatial and spectral optical technologies.

Digital Techniques for Documenting and Preserving Cultural Heritage

Si les possibilites de numerisation 3D de la presente realite d'un site archeologique par le biais des dernieres techniques d'acquisition 3D (photogrammetrie/scan laser) aident a la comprehension de son fonctionnement, elles peuvent aussi permettre de veritables hypotheses de reconstitutions de celui-ci tel qu'il a pu l'etre a une epoque donnee. Les besoins de la communaute archeologique concernant ces restitutions de structures ou d'environnements sont en effet considerables car, au-dela d'un interet evident en termes de valorisation du patrimoine, celles-ci permettent de veritablement mieux apprehender leurs fonctionnements et les societes qui les ont occupes. C'est partant de ce contexte que le premier objectif de cette these a ete d'operer, traiter et analyser differents niveaux de production d'environnements archeologiques 3D pour la recherche archeologique. Le second objectif a concerne la conception et la mise en place de methodes d'interactions et de simulations immersives pour que les archeologues puissent demontrer certaines hypotheses, notamment en travaillant sur la perception d'indices visuels pertinents.

Techniques de production, d'exploration et d'analyse d'environnements archéologiques virtuels

Digital documentation and high-quality 3D representation are always more requested in many disciplines and areas due to the large amount of technologies and data available for fast, detailed and quick documentation. This work aims to investigate the area of medium and small sized artefacts and presents a fast and low cost acquisition system that guarantees the creation of 3D models with an high level of detail, making the digitalization of cultural heritage a simply and fast procedure. The 3D models of the artefacts are created with the photogrammetric technique Structure From Motion that makes it possible to obtain, in addition to three-dimensional models, high-definition images for a deepened study and understanding of the artefacts. For the survey of small objects (only few centimetres) it is used a macro lens and the focus stacking, a photographic technique that consists in capturing a stack of images at different focus planes for each camera pose so that is possible to obtain a final image with a higher depth of field. The acquisition with focus stacking technique has been finally validated with an acquisition with laser triangulation scanner Minolta that demonstrates the validity compatible with the allowable error in relation to the expected precision.

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Sfm technique and focus stacking for digital documentation of archaeological artifacts

Misura e Historical Information Building: sfide e opportunità nella rappresentazione di contenuti 3D semanticamente strutturatiMeasurement and Historical Information Building: challenges and opportunities in the representation of semantically structured 3D content

. Thanks to their playful and educational approach Virtual Museum systems are very effective for the communication of Cultural Heritage. Among the latest technologies Immersive Virtual Reality is probably the most appealing and potentially effective to serve this purpose; nevertheless, due to a poor user-system interaction, caused by an incomplete maturity of a specific technology for museum applications, it is still quite uncommon to find immersive installations in museums. This paper explore the possibilities offered by this technology and presents a workflow that, starting from digital documentation, makes possible an interaction with archaeological finds or any other cultural heritage inside different kinds of immersive virtual reality spaces. Two different cases studies are presented: the National Archaeological Museum of Marche in Ancona and the 3D reconstruction of the Roman Forum of Fanum Fortunae. Two different approaches not only conceptually but also in contents; while the Archaeological Museum is represented in the application simply using spherical panoramas to give the perception of the third dimension, the Roman Forum is a 3D model that allows visitors to move in the virtual space as in the real one. In both cases, the acquisition phase of the artefacts is central; artefacts are digitized with the photogrammetric technique Structure for Motion then they are integrated inside the immersive virtual space using a PC with a HTC Vive system that allows the user to interact with the 3D models turning the manipulation of objects into a fun and exciting experience. The challenge, taking advantage of the latest opportunities made available by photogrammetry and ICT, is to enrich visitors’ experience in Real Museum making possible the interaction with perishable, damaged or lost objects and the public access to inaccessible or no longer existing places promoting in this way the preservation of fragile sites.

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Interactive immersive virtualmuseum: digital documentation for virtual interaction

The possibility of applying the BIM approach is an interesting challenge in the framework of 3D modelling and management/enhancement of historic buildings, especially high cultural and architectural value A big challenge in reality based modelling is to develop simple methods to get HBIM models for cultural heritage, that guarantee accuracy, precision and quality of representation compliant with the acquired data The present work, dealing with two cases study, highlights the feasibility of a whole approach and opens the way for the development of centralized HBIM that can be used as complete data set of information on all disciplines, in particular for the heritage restoration and preservation, but also for its dissemination and exploitation Similar methods facilitate the HBIM diffusion for the management of survey and restoration processes of historic buildings

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Measurement and Historical Information Building: challenges and opportunities in the representation of semantically structured 3D content

In recent years, the technologies for creating reality-based 3D models were enhanced and propagated in a large number of applications and research fields. This great evolution is due to the fact that these technologies are very useful, or rather ideal, to preserve, disseminate and restore cultural heritage, thanks to digitization and the realization of digital copies based on additive printing. In particular, 3D printing and virtual reality have determined the increase of a new field for data survey: the museum fruition. Therefore, they are becoming increasingly important. The aim of this article is to show the connection and the relationship between the development of the latest technologies and the cultural heritage: a digital reconstruction procedure from laser scanning survey to 3D printing of theoretical model, realized with a virtual reconstruction reality-based.

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Ludovico Ruggeri

Papers

Sfm technique and focus stacking for digital documentation of archaeological artifacts

Misura e Historical Information Building: sfide e opportunità nella rappresentazione di contenuti 3D semanticamente strutturatiMeasurement and Historical Information Building: challenges and opportunities in the representation of semantically structured 3D content

Interactive immersive virtualmuseum: digital documentation for virtual interaction

Measurement and Historical Information Building: challenges and opportunities in the representation of semantically structured 3D content

A digital reconstruction procedure from laser scanner survey to 3D printing: the theoretical model of the Arch of Trajan (Ancona)