Robust multi-scale design of meta-structures for mechanical cloaking from additive manufacturing processes – METACLOAK

Additive manufacturing (AM) technologies can be efficiently exploited together with modern generative design software to design and manufacture composite structures characterised by unconventional physical properties. Among them, one can imagine designing meta-structures to achieve mechanical cloak. Mechanical cloak should be interpreted as the ability of the meta-structure to be insensitive to a peculiar phenomenon/characteristic/external solicitation. For example, one can imagine optimising the anisotropy and the topology of the structure to make it insensitive to the presence of geometrical discontinuities, e.g., holes. In this way, the metastructure with a hole can show the same stress field of a reference structure without the hole. The concept of “mechanical cloak” can be extended to other phenomena, like buckling, vibrations, etc. However, general design strategies capable of concurrently optimising the anisotropy and the topology of the materials composing the meta-structure at each scale to achieve an efficient mechanical cloak do not exist yet. In this context, the integration of the uncertainty related to the AM process and of the strong coupling between the scales in the design process are two major challenges to be faced. This project aims to propose a new paradigm to design composite meta-structures that is based on: a CAD-compatible robust topology/anisotropy optimisation algorithm based on tensor invariants (to represent the anisotropy of the materials composing the meta-structure), higher-order theories to correctly describe the mechanical response of the meta-structure, a dedicated formalisation of the manufacturing requirements and uncertainty related to the AM process to get optimised and manufacturable solutions.