A stress-based topology optimization method by a Voronoi tessellation Additive Manufacturing oriented

The work presents a stress-based algorithm developed for the topology optimization of 3D surfaces. The novelty of the proposed methodology consists in the fact that it acts directly on a CAD level, and not on the mesh as is more usual. This allows to obtain a CAD ready to be manufactured with Additive Manufacturing technologies, without any subsequent intervention by the designer. The CAD algorithm is written in Rhino-Grasshopper environment and it is suitable to any FEM software. The methodology consists in a hollowing of the surface, starting by a Voronoi tessellation, allowing the designer to set a lot of parameters, as the number of control points, the dimension of the holes and the thickness of the branches of the tessellation. An iterative process leads to redraw at each iteration the Voronoi scheme in order to add material where the stress is higher and to remove it where the stress is lower. As a case study, in order to show the characteristics of the methodology, a seat for powerboats applications has been tested and optimized. The results from the case study demonstrate the high performance of the method and the capability to obtain in easy way light weight structures oriented for the Additive Manufacturing new technologies.