Parameterization of prismatic shapes and reconstruction of free-form shapes in reverse engineering

The objective of this study is to propose a method for reverse engineering prismatic and free-form shapes. The primary focus is on feature-based parameterization of digitized geometries so that they can be further used in downstream MCAD (mechanical computer-aided design) applications. The study takes advantage of a 3D body scanner for rapid digitizing purpose to acquire denser point clouds with no more than three scans. Suggested are five basic steps towards successful reverse engineering prismatic and free-form shapes. They include acquisition of a raw point cloud data, processing of raw data, mesh generation, surface reconstruction, and feature-based parameterization. In this study, three different sample parts that include a mechanical nozzle, a hubcap, and a bucket seat, were reverse engineered to demonstrate the proposed methodology. This process was proven effective toward reconstruction of free-form NURBS (non-uniform rational B-spline) surfaces. It also proved efficient towards feature-based parameterization of prismatic shapes.