A parametric feature-based approach to reconstructing traditional filigree jewelry

This paper presents a novel approach to reconstructing traditional filigree jewelry. We study how such traditional pieces can be re-engineered 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 freeform artistic alterations). To achieve this, we have studied the patterns that are identified in such jewelry and provide a methodology for deriving an accurate and robust representation using 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 in filigree jewelry. In addition we have developed a suite of software tools, called ReJCAD, that given a point cloud derived by high accuracy 3D laser scanning of jewelry piece, detects ornamental components that are identified as features and are subsequently fitted by elements of the patterns library. The point cloud also serves as a guide for assembling all patterns in one robust manufacturable solid piece. We demonstrate the unique capabilities of ReJCAD by reconstructing a filigree brooch part of formal traditional regional clothing used in late 19 th century at northwestern Greece.