A signal-processing-driven framework for the reconstruction and machining of sculptured surfaces from coordinate measurement data
摘要
The reverse engineering and manufacturing of sculptured surfaces remain challenging due to the limitations of traditional CAD/CAM workflows in handling complex, free-form geometries. This paper presents a novel, integrated framework that reconceptualizes the surface reconstruction problem through the lens of signal processing. The methodology begins with the acquisition of 3D point cloud data via a Coordinate Measuring Machine (CMM). A key novelty lies in the application of a two-dimensional Fourier Transform (2D-FT) to the height map of the digitized surface, enabling a frequency-domain analysis that diagnostically informs data preprocessing and optimizes machining direction. The framework subsequently evaluates and applies advanced geometric modeling techniques, including triangle-based cubic interpolation and Non-Uniform Rational B-Splines (NURBS), to generate a high-fidelity CAD model. Finally, the CAM phase incorporates geometric and kinematic analyses, such as curvature-adaptive tool path generation using Voronoi diagrams and 3D velocity vector calculation, to ensure gouge-free machining and adherence to machine kinematic constraints. Experimental results on a complex sample surface demonstrate the framework’s efficacy: the 2D-FT successfully identified dominant surface frequencies, guiding the machining strategy; cubic interpolation provided a superior surface fit with a 60% reduction in visual artifacts compared to linear interpolation; and kinematic analysis preemptively identified potential machining instability zones, potentially reducing servo errors by adaptively controlling feed rates. This work establishes a foundational step towards intelligent, fully automated manufacturing systems by providing a diagnostic, data-driven pipeline from measurement to machining, directly applicable to industries like aerospace and automotive mold-making.