Synthesizing patterned surfaces for 3D printing

Abstract

Recent years have witnessed the advancement of 3D printing in fabricating objects with sophisticated and highly-customized geometries. The print services are now widely available through online orders, home printers, and local FabLabs. Nevertheless, it remains difficult for most users to create interesting objects, even more so when the intended design has complex geometry details. To circumvent this issue, in this thesis we present approaches to automate the task of designing and fabricating artistic patterned surfaces.

We firstly present a novel approach to synthesize fabricable filigrees. As thin patterns widely found in jewelry, ornaments and lace fabrics, filigrees are often manually designed by composing repeated base elements. We propose a novel method to automate this challenging task. Our technique covers a target surface with a set of input base elements, forming a filigree strong enough to be fabricated. We leverage the fact that as traceries, filigrees can be well captured by their skeletons. This affords for a novel energy function that measures the matching quality between base elements. In addition, instead of seeking for a perfect packing of base elements, we relax the problem by allowing appearance-preserving partial overlaps. The formulation is optimized by a stochastic search, which is further improved by a boosting step that records and reuses good configurations discovered during the process. Our technique affords for multi-class synthesis and several user controls, such as scale and orientation of the elements.

Second, we extend the method to generate complex -- yet easy to print -- tile decorations. The user only provides base surface and a set of tiles. Our algorithm automatically decorates the base surface with the tiles. However, rather than being simple decals, the tiles \textit{become} the final object, producing shell-like surfaces that can be used as ornaments, covers, shades and even handbags. Our technique is designed to maximize print efficiency: the results are printed as independent flat patches that are articulated sets of tiles. The patches could be assembled into the final surface through the use of snap-fit connectors. Our approach proceeds in three steps. First, a dedicated packing algorithm is proposed to compute a tile layout while taking into account fabrication constraints, in particular ensuring hinges can be inserted between neighboring tiles. A second step extracts the patches to be printed and folded, while the third step optimizes the location of snap-fit connectors. Our technique works on a variety of objects, from simple decorative spheres to moderately complex shapes.