Objective and context :

• The first route describes general mesh decimation methods which operate on triangle meshes. The goal of the mesh decimation is the reduction of triangles in a mesh while preserving the shape and topology as good as possible. All the output and data of the optical device measurement are given under the form of an initial mesh (STL format) containing possibly a huge number of elements which can be used as the first guess of the decimation procedure. The existing version of the mesher can deal easily with such meshes as well as the metric map which preserves the geometrical details is well defined. The main drawback of this approach is that the current mesh technology requires that the initial mesh is a true mesh with connected elements.

 

• The second route consists on the use of the Level Set method combined to an anisotropic adaptive meshing. At this stage, we assume that the surface is still defined by a possibly huge number of triangles not anymore strictly connected. The idea is to use an immersed surface technique by means of the Level Set framework and then to adapt the background mesh until the aimed domain is a part of it. To perform that we need to combine the PDE level set solver, the interpolation error analysis with metric construction and the adaptive remeshing procedure under the lower number of elements. This will result the geometry reconstruction by mesh adaptation.

 

• The last point is described by the trajectory calculation from LS definition. Here, the objective is to explore the possibility to use the adapted level set volume description to calculate directly the required trajectories inside the volume of the background mesh. More generally, it will open the door towards the required actual objectives into the adaptive procedure.