Geometrical errors after restoration.

C. Launoy and Benjamin Chauvin and Antoine Mazuyer. ( 2015 )
in: 35th Gocad Meeting - 2015 RING Meeting, ASGA

Abstract

Restoration is a retro-deformation of 3D models to return into its most likely initial configuration. It is useful for understanding the stress state of an environment or to validate a 3D structural model. As the restored model must be correct, it must respect many constraints such as defined contacts, boundary conditions or continuity of rocks. The studied environment, composed of layers, can be faulted or folded. In this article, we consider the restoration as a finite element problem. The model is divided into small cells that compose a mesh. During the solving of the finite element problem, two types of errors can exist: geometrical and numerical ones. In this article, only some geometrical errors will be checked. They are linked to the mesh and the non respect of the contact conditions. By changing the geometry, tetrahedra can be deformed or moved and can intersect one another. Contact conditions are checked by verifying all the points that must touch another object (point, line or surface). The distance between the elements that must have a contact is returned and can checked against a minimal tolerated distance. Intersections in the mesh are identified by detecting cells overlaps and more precisely when a node of a tetrahedron is in another tetrahedron. It tracks down the intersection by giving the index of the cells in the mesh and its region. These geometrical tests can be extended to any problem that change or damage the mesh or problems in which contact conditions must be respected.

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BibTeX Reference

@inproceedings{LaunoyGM2015,
 abstract = { Restoration is a retro-deformation of 3D models to return into its most likely initial configuration. It is useful for understanding the stress state of an environment or to validate a 3D structural model. As the restored model must be correct, it must respect many constraints such as defined contacts, boundary conditions or continuity of rocks. The studied environment, composed of layers, can be faulted or folded. In this article, we consider the restoration as a finite element problem. The model is divided into small cells that compose a mesh. During the solving of the finite element problem, two types of errors can exist: geometrical and numerical ones. In this article, only some geometrical errors will be checked. They are linked to the mesh and the non respect of the contact conditions. By changing the geometry, tetrahedra can be deformed or moved and can intersect one another. Contact conditions are checked by verifying all the points that must touch another object (point, line or surface). The distance between the elements that must have a contact is returned and can checked against a minimal tolerated distance. Intersections in the mesh are identified by detecting cells overlaps and more precisely when a node of a tetrahedron is in another tetrahedron. It tracks down the intersection by giving the index of the cells in the mesh and its region. These geometrical tests can be extended to any problem that change or damage the mesh or problems in which contact conditions must be respected. },
 author = { Launoy, C. AND Chauvin, Benjamin AND Mazuyer, Antoine },
 booktitle = { 35th Gocad Meeting - 2015 RING Meeting },
 publisher = { ASGA },
 title = { Geometrical errors after restoration. },
 year = { 2015 }
}