3D scanning and digital fabrication technologies are rapidly evolving, and their combination has the potential to dramatically change the way we design functional objects by enabling the fabrication of objects with an unprecedented geometrical complexity while drastically speeding up the design iterations. The goal of this project is to lay the algorithmic foundation for tightly integrating 3D scanning and digital fabrication, to support new applications in life sciences and medicine. To this end, the research will transform the traditional geometry processing pipeline by proposing a new data representation and new algorithms specifically designed to support fabrication and scanning. In contrast to traditional global optimization methods, which struggle to deal with massive and noisy datasets, the PI focuses on semi-local algorithms that are robust, easy to parallelize and have a small memory footprint. The research will have two major thrusts: Scanning for Fabrication (ScanFab), and Fabrication for Scanning (FabScan). The ScanFab pipeline will support medical applications that require the design of customized medical devices and prostheses; to validate its effectiveness, the PI will collaborate with corporate partner Sonova to acquire and reconstruct the geometry of the ear canal, and to provide interactive techniques for designing the next generation of customized hearing aids. The FabScan thrust will lead to the development of a novel microscopy technique for estimating 2D and 3D traction forces on the surface of cells, which will be fundamental to understanding cell migration in development and cancer genesis; the technique will be developed in collaboration with the Dept. of Mechanical and Process Engineering at ETH Zurich, and will be evaluated in a large biological study in collaboration with the medical school in the University of Milano. The developed techniques will be integrated into the PI's open-source library, to allow the research community to directly benefit from these contributions.
In ScanFab, the PI introduces an integrated pipeline to acquire, modify, simulate, and fabricate a variant of an existing 3D object. The pipeline is based on T-meshes, a geometrical representation that combines the benefits of coarse and highly structured quadrilateral meshes with the efficiency and flexibility of triangle meshes. The research will tackle: (1) the interactive and out-of-core conversion of point clouds to T-meshes; (2) the interactive editing of the reconstructed surfaces while ensuring fabricability; (3) the physical simulation of the new geometry to study its mechanical properties before fabrication, using a Finite Element Method (FEM). In FabScan, the pipeline will be reversed to sense forces at the microscopic level. The PI will fabricate a microstructure with a known geometry and physical properties, apply loads to it, and then acquire the deformed geometry via 3D confocal microscopy. The traction forces will be accurately reconstructed by solving an inverse FEM problem, combining the knowledge of the initial and of the deformed geometry.
