In this paper, the authors describe a reverse engineering system, named BitCAT, for machine
engineering using 3D bit-map data obtained from CT digitizers. BitCAT can compose B-Rep CAD
models by fitting parametric primitives, such as flat planes and cylinders, onto 3D bit-map surfaces.
To find boundaries of the primitives effectively, a novel interactive “growing surface method” is
developed and applied in the system. BitCAT is also provided with a method to determine
geometric constraints between the primitives during composition processes. BitCAT can make
very useful CAD models for manipulation and NC machining, because they are properly attached
with geometrical features. A demonstration verifies the faculty and usefulness of the system.Mechanical Engineerin
