Eurographics Conferences

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https://diglib.eg.org/handle/10.2312/187
EUROGRAPHICS 2024, Limassol: Conference Procceedings online

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Browsing Eurographics Conferences by Subject "aided design"

Now showing 1 - 5 of 5
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    Iterative Carving for Self-supporting 3D Printed Cavities
    (The Eurographics Association, 2018) Hornus, Samuel; Lefebvre, Sylvain; Diamanti, Olga and Vaxman, Amir
    Additive manufacturing technologies fabricate objects layer by layer, adding material on top of already solidified layers. A key challenge is to ensure that there is always material below, for otherwise added material simply falls under the effect of gravity. This is a critical issue with most technologies, and with fused filament in particular. In this work we investigate how to compute as large as possible empty cavities which boundaries are self-supporting. Our technique is based on an iterated carving algorithm, that is fast to compute and produces nested sets of inner walls. The walls have exactly the minimal printable thickness of the manufacturing process everywhere. Remarkably, our technique is out-of-core, sweeping through the model from the top down. Using our approach, we can print large objects using as little as a single filament thickness for the boundary, providing one order of magnitude reduction in print time and material use while guaranteeing printability.
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    Procedural Bridges-and-pillars Support Generation
    (The Eurographics Association, 2022) Freire, Marco; Hornus, Samuel; Perchy, Salim; Lefebvre, Sylvain; Pelechano, Nuria; Vanderhaeghe, David
    Additive manufacturing requires support structures to fabricate parts with overhangs. In this paper, we revisit a known support structure based on bridges-and-pillars (see Figure 1). The support structures are made of vertical pillars supporting horizontal bridges. Their scaffolding structure makes them stable and reliable to print. However, the algorithm heuristic search does not scale well and is prone to produce contacts with the parts, leaving scars after removal. We propose a novel algorithm for this type of supports, focusing on avoiding unnecessary contacts with the part as much as possible. Our approach builds upon example-based model synthesis to enable early detection of collision-free passages as well as non-reachable regions.
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    State-of-the-art in Automatic 3D Reconstruction of Structured Indoor Environments
    (The Eurographics Association and John Wiley & Sons Ltd., 2020) Pintore, Giovanni; Mura, Claudio; Ganovelli, Fabio; Fuentes-Perez, Lizeth Joseline; Pajarola, Renato; Gobbetti, Enrico; Mantiuk, Rafal and Sundstedt, Veronica
    Creating high-level structured 3D models of real-world indoor scenes from captured data is a fundamental task which has important applications in many fields. Given the complexity and variability of interior environments and the need to cope with noisy and partial captured data, many open research problems remain, despite the substantial progress made in the past decade. In this survey, we provide an up-to-date integrative view of the field, bridging complementary views coming from computer graphics and computer vision. After providing a characterization of input sources, we define the structure of output models and the priors exploited to bridge the gap between imperfect sources and desired output. We then identify and discuss the main components of a structured reconstruction pipeline, and review how they are combined in scalable solutions working at the building level. We finally point out relevant research issues and analyze research trends.
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    Towards the Fitting of Parametric 2D Sketches and 3D CAD Models to Point Clouds of Digitized Assemblies for Reverse Engineering
    (The Eurographics Association, 2019) SHAH, Ghazanfar Ali; Giannini, Franca; monti, marina; Polette, Arnaud; PERNOT, Jean-Philippe; Fusiello, Andrea and Bimber, Oliver
    Following commonly used reverse engineering techniques, it is very difficult to reconstruct editable CAD parts or assemblies that can later be used and modified in the Product Development Process (PDP). Traditional methods follow a sequential time-consuming patch-by-patch reconstruction strategy with cumbersome procedures in which designers usually have to face many issues (e.g. decomposition in patches, trimming and connection of the patches), and generally producing ''dead'' models that cannot be later modified as needed. This paper describes a new reverse engineering technique that allows fitting of parametric CAD parts or an assembly to a reference point cloud to be reconstructed. The proposed fitting method can also be applied to 2D configurations to adapt a parametric 2D sketch to a 2D point cloud section. The idea is to use a parametric CAD model or a parametric 2D sketch in an optimization algorithm allowing their perfect fitting into the point cloud of a scanned mechanical assembly for efficient reconstruction of good quality CAD models. Some well-known algorithms like ICP are also used to derive the orientation and position of pre-arranged CAD model or 2D sketch throughout the fitting process. Both global and local fittings are possible. The consistency of the CAD models is ensured by a modeler which updates the CAD models or 2D sketch according to the iterative dimensional modifications. The evaluation of the proposed approach is performed using as-scanned virtually generated point clouds which incorporate several artifacts that would appear using a real scanner. This technique allows for the comparison between the dimensions of the fitted parts and the ones of the parts used to generate the point clouds.
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    The Use of Photogrammetry in Historic Preservation Curriculum: A Comparative Case Study
    (The Eurographics Association, 2024) Kepczynska-Walczak, Anetta; Walczak, Bartosz M.; Zarzycki, Andrzej; Sousa Santos, Beatriz; Anderson, Eike
    Computer graphic techniques have emerged as a key player in digital heritage preservation and its dissemination. Photogrammetry allows for high-fidelity captures and virtual reconstructions of the built environment that can be further ported into virtual reality (VR) and augmented reality (AR) experiences. This paper provides a comparative analysis of historic details and building documentation methods in heritage preservation in the context of architectural education. Specifically, it compares two educational case studies conducted in 10-year intervals documenting the same set of historic artifacts with corresponding state-of-the-art digital technologies. The methodology for this paper is a qualitative comparative analysis of two surveying projects that utilized distinct emerging digital technology while sharing the same study subjects and similar tool-driven curricular framework. The research also incorporates a student survey, offering perspectives on teaching strategies and outcomes within this dynamic educational context. The outcomes demonstrate that the technological (tool-driven) shift impacts the way students interact with the investigated artifacts and the changing role of the interpretative versus analytical skills needed to delineate the work. It also changes what are considered primary and secondary knowledge sources.