From 3D Models to 3D Prints: an Overview of the Processing Pipeline <s> Microstructures <s> The ability to pattern materials in three dimensions is crucial for structural, optical, electronic, and energy applications. Three-dimensional printing allows one to design and rapidly fabricate materials in complex shapes without the need for expensive tooling, dies, or lithographic masks. A growing palette of printable materials, coupled with the ability to programmably control mesoscale architecture, open new avenues for creating designer materials with unprecedented performance. <s> BIB001 </s> From 3D Models to 3D Prints: an Overview of the Processing Pipeline <s> Microstructures <s> Microstructures at the scale of tens of microns change the physical properties of objects, making them lighter or more flexible. While traditionally difficult to produce, additive manufacturing now lets us physically realize such microstructures at low cost. In this paper we propose to study procedural, aperiodic microstructures inspired by Voronoi open-cell foams. The absence of regularity affords for a simple approach to grade the foam geometry --- and thus its mechanical properties --- within a target object and its surface. Rather than requiring a global optimization process, the microstructures are directly generated to exhibit a specified elastic behavior. The implicit evaluation is akin to procedural textures in computer graphics, and locally adapts to follow the elasticity field. This allows very detailed structures to be generated in large objects without having to explicitly produce a full representation --- mesh or voxels --- of the complete object: the structures are added on the fly, just before each object slice is manufactured. We study the elastic behavior of the microstructures and provide a complete description of the procedure generating them. We explain how to determine the geometric parameters of the microstructures from a target elasticity, and evaluate the result on printed samples. Finally, we apply our approach to the fabrication of objects with spatially varying elasticity, including the implicit modeling of a frame following the object surface and seamlessly connecting to the microstructures. <s> BIB002
Micro-structures are internal infill patterns that seek to change the macroscopic physical behavior of the final object. For instance, even when printing with a single material certain micro-structures modify the elastic behavior of the object, making it more or less flexible. It is often possible to grade and control the change across the final object. Figure 10 ). BIB002 consider procedural Voronoi-based microstructures, that can be fabricated with SLA/SLS. Micro-structures are a very promising field of research, with many potential applications BIB001 . We envision that efficient techniques for designing and fabricating micro-structures will tightly integrate with process planning.