Surface reconstruction from medical imaging for use in a computer-aided-design (CAD) environment.

摘要

A method was developed to create Computer-Aided-Design (CAD) models for bones of the human body utilizing medical imaging data. The human hand was chosen as the subject of the research.;Computed Tomography (CT) imaging was chosen to provide a volumetric data set. This data set was visualized through an isosurfacing technique utilizing the marching cubes algorithm. The original CT data set contained slices that were not aligned with the natural orientation or long axis of the bones. Transformation matrices and linear interpolations were used to generate a data set of slices oriented along the natural axis of the bones.;Contours were created on these slices through an edge-tracking method. B-Spline curves were then constructed utilizing the contour's vertices as knot points. A consistent starting location was found on each closed B-Spline curve relative to its centroid. Points on the closed B-Spline curves were then selected to define open non-uniform B-Spline curves in Pro/Engineer, a common CAD software package. Pro/Engineer was then utilized to trim the B-Spline curves to obtain their uniform portions. Cross-curves were developed through groupings of parallel B-Spline curves in order to define a closed boundary for a Boundary Blend surface patch. These surface patches were joined to adjacent surface patches and maintained C 2 curvature continuity.;The method presented applied common visualization techniques to a data set from CT imaging. This provided vertices from which to construct curves and surfaces in a CAD environment resulting in the ability to create detailed anatomical CAD models.