PSI - Issue 64

Luca Belluomo et al. / Procedia Structural Integrity 64 (2024) 2197–2205 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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model both in STL format and in OBJ (useful for the RGB information needed to let the heritage experts be able to recognize each portion of the retrieval). Parallely, information and decisions about the exhibitional environment and case can be made, following the requirements of heritage experts and museal needs. This is made possible also by developing a 3D virtual environment, importing not only the models of the retrievals but also the acquisitions or 3D models of the exhibition cases and, eventually the acquisitions of the museum rooms. For being visualized the 3D environment is developed in a dedicated platform, ESI IC.IDO. In the virtual environment, the heritage experts can visualize the rendered models inside the exhibitional case within the museum rooms. This gives the possibility to decide the positioning of the retrieval in terms of relative position in respect to the exhibitional case (height and x-y location) and it can also give a first attempt of orientation in terms of angles. This means the choice of the position of the center of mass of the model and a first attempt of the angles in respect to the reference planes. After that, the angle of inclination of the piece can be optimized in the sagittal plane in relation to the relative position of the possible standard user, following the criteria of giving to the user the possibility to see the widest portion possible from a frontal position. This optimized angle is given by (1): = 2 − ( −(ℎ +ℎ ) ); (1) where D u is the prescribed distance of the standard user (distance of the point of view), H u is the height of the eyes of the standard user (height of the point of view), h cm is the chosen height of the center of mass in respect to the exhibitional case plane, h b is the height of the plane of the exhibitional case, as in Fig. 1.

Fig. 1. Scheme of the optimal sagittal angle of inclination ( ). Once the position and the orientation are chosen, the procedure of GD can start. As reported in Belluomo et al. 2023, once the fragment has been oriented, the modeling process of the interfaces (C i ) of the support with the fragment can start by defining the curves on the surface of the fragment where the clamps are allowed to be positioned. Afterwards, the modeling of the clamps, the parametric optimization procedure for their extension and position along the fragment can be performed. Then, a final configuration ready for the generative design process is obtained. Since the supporting structure must be hidden as much as possible by the fragment in the observer point of view, a procedure in Grasshopper and MATLAB has been developed to define the boundary of the fragment in a plane orthogonal to the observer viewpoint to obtain an upper limit envelope for the design of the support. The outer envelope is an obstacle geometry for the generative design phase along with the fragment, and the basement plane and the bolt connectors for the interface between the support and the basement plane. Inside the boundary defined by the intersection between the outer envelope and the basement plane, it is possible to define the elements of the support that are in contact with the basement plane, assuming the support will be screwed to the basement. Concerning the loading condition, the weight