Downloaded from https://www.everyspec.com APPENDIX C MIL-STD-31000A Finite element analysis: Excessive numbers of small elements may be generated. Mesh generation may fail. Numerically controlled manufacturing: Offset surfaces and tool-path generation may fail. Gouging of the work piece may occur. Recommended correction: Defective surfaces should be deleted and recreated with properly oriented normal vectors. Where folding occurs at the tip of a triangular patch, trim the triangular patch and substitute a proper three-sided patch or surface. C.7.2.16. Wavy surface (G-SU-WV). Definition: Curvature of the surface changes sign too many times. Number of changes in curvature sign = N.
Effects of condition on CAD data quality: Design and drafting: Aesthetically unacceptable in most cases. Data exchange: Waviness may be accentuated upon translation. Waviness may be an artifact of poor translation. Finite element analysis: Excessive numbers of small elements may be generated. Numerically controlled manufacturing: Waviness will appear in the work piece. Recommended correction: Delete the surface and recreate it using suitable degree, edge curves, knots, and control points. C.7.2.17. Small Surface Radius of Curvature (G-SU-CR). Definition: Radius of curvature, R, within the surface is below the minimum allowable value. 101