Automatic Hole Detection
When automatic detection of fastener holes is used in the Hole Selection subnode under Fasteners, the algorithm attempts to find matching hole pairs on the source and destination boundaries. For two holes to be considered as a pair, and thus connected, the following criteria must be met:
•
Both holes are circular.
•
They have the same radius within a certain tolerance εr. The default limit is εr =  1%.
•
The boundaries are locally parallel. The angle between the two normal vectors must be less than α, with the default value α =  2°.
•
The centers of the two holes must lie on a common line. This line is represented by the normal to the source boundary, passing through the center of the hole in the source boundary. What is measured is the ratio between the projection of the distance between the two hole centers, b, on that line, and the hole radius. The default allowed value is εc =  1%
Figure 3-46: Symbols used for hole detection tolerances.