Object model reconstruction from complex planar cross sections

I. Introduction A system for constructing 3-D models for complex objects from a series of planar cross-sectional contours is important for many application areas of CAD/CAM which include design, structure analysis, manufacturing, and inspection. Such a system is especially important in reverse engineering since it generates a solid model from an actual workpiece automatically. Cross sectional contours represent the boundary of either the external surface of the workpiece or the surface of internal structures. The workpiece is scanned, with a very small scanning interval, along its major axis. For each planar cross section, its density image is reconstructed from projections by using the X-ray based computer tomographic techniques and the contour points are extracted from the density images by using image processing techniques.