POINT NORMAL INTERPOLATION FOR STEREOLITHOGRAPHY MODELING

Stereolithography apparatus can be used to produce a physical model of an existing object. Since actual production of the physical model can be quite expensive, it is desirable to develop an intermediate geomet ric model of the physical object from measured data. The geometric mod el can be obtained by approximating the surface of the object by a col lection of surface patches. Parametric cubic curve segments which inte rpolate between two given points such that the principal normal direct ions at the two points are parallel to specified directions, can be us ed as boundary curves for such surface patches. Some properties of thi s interpolation technique are discussed.