1. Field of the Invention
The present invention relates to an outline extracting apparatus using a CAD (Computer Aided Design) data and a non-contact measuring point data obtained by non-contact measuring an object, a method for extracting an outline, a computer readable memory medium stored with an outline extracting program and a computer readable memory medium stored with an outline data.
2. Description of Background Art
Heretofore, there has been used a method for connecting two points in a point group forming a non-contact measuring point data using a straight line as a method for extracting an outline of an object (i.e. an article to be inspected) on a computer by using a non-contact measuring instrument such as a three dimensional scanner. The outline of the object is extracted by the conventional method by obtaining a data of the point group by non-contact measuring an article 30 to be inspected (FIG. 13) using the three dimensional scanner, and connecting two points in the obtained point group by a straight line to form a plurality of triangles.
However, although the side 31 of the article 30 to be inspected is flat surface not having any irregularity, the extracted surface obtained according to the method of the prior art for extracting the outline of the object exhibits undulation as shown by a dashed line “n” in FIG. 14. This is because of the presence of dispersion in the data of the point group caused by the error of the non-contact measuring instrument. Thus it is very difficult to extract a flat surface by the conventional method.
In addition, an outline 33 formed by the upper surface 32 and the side surface 31 of the article 30 to be inspected as well as an outline 35 formed by the inclined surface 34 and the side surface 31 exhibit a rounded configuration as shown by a dashed line “m” in FIG. 14 which is different from the real outlines 33 and 35 each forming an acute edge. This is because that the data of the point group does not necessarily lie on the outlines 33 and 35. Thus it is very difficult to exactly extract the corner outline having an acute angle by the conventional method.