ReJCAD: A Feature-based CAD System for Reconstructing Traditional Filigree Jewelry

This paper presents a novel approach to reconstructing traditional filigree jewelry. Our method aims at producing an editable CAD representation that can accurately capture the original design and be capable of re-parameterization and modification prior to manufacturing (for example to insert custom designs and abide to free-form artistic alterations). To achieve this, we have developed robust and accurate representations of patterns, used in the design of such jewelry, based on spirals, circular and elliptic arcs, curve segments and braids of various types; all optimized by fairness criteria for aesthetic purposes. We have also built a library of parametric, constraint-based, manufacturable solid patterns that occur frequently in filigree jewelry. For the purposes of this work, a suite of software tools called ReJCAD has been developed, that is able to process a highly accurate point-cloud of jewelry pieces and to detect features which are fitted by the primitives of the pattern library through user interaction. The point cloud, in the current framework, guides the assembling of all patterns into one robust manufacturable solid piece. We demonstrate the unique capabilities of ReJCAD by reconstructing a filigree brooch part commonly used in late 19th century at northwestern Greece.