Downloaded from https://www.everyspec.com APPENDIX C MIL-STD-31000A Effects of condition on model-based definition translation: If one of the faces in the native model has annotations which reference it, exclusive of the others in the merged set, then it will be impossible to preserve the original definition in the translated model. C.9.1.4 Deviant Faces (G-FA-DV) Definition: A set of translated faces have a significant geometric deviation from the matching face(s) in the native model. Measurement: Maximum distance between any location on the native face(s) and the closest location on the translated face(s).
The use of Greville sampling points is recommended for faces defined on NURBS surfaces. Effects of condition on model-based definition translation: If the magnitude of the geometric deviation is a significant percentage of the manufacturing tolerance assigned to these faces, the translated model is not an equivalent representation of the native model because the nominal definition will have changed without a corresponding change in the tolerance. Or if these faces are associated with a datum, any significant deviation will likewise invalidate the equivalence of the derived model. C.9.1.5 Different Face Type (G-FA-DT) Definition:
The geometric type of the surface on which a translated face is defined is different than the type of the surface on which the matching native face is defined. Measurement: The criterion is false if any occurrences of this condition exist in the model pair. Effects of condition on model-based definition translation: Generally, a change in geometric surface type corresponds to the loss of parametric information which may be critical to the product definition. For example, a face defined on a cylindrical surface with a specific radius of curvature that is translated 139