Downloaded from https://www.everyspec.com APPENDIX C MIL-STD-31000A Figure 21. Report showing quality defects that could not be corrected automatically. At this point, the CAD operator can choose to correct errors by going back to the original CAD model and making revisions or by proceeding interactively with data-healing tools. If the process dictates that features be preserved (for example) if original CAD data is being checked into a PDM system), then correcting errors in the native CAD format is necessary. Many popular CAD programs have tools for checking CAD geometry. These tools may indicate the location of at least some of the errors found by geometry validation software.
Often dirty geometry in CAD models is caused by poor modeling practices. For example, if a designer has put two nearly-overlapping geometric features in the same place, troublesome geometry may occur near the feature boundaries. Rationalizing dimension-driven features in these local areas will often fix the problems. If everything possible has been done to produce clean CAD models, and if models are being translated for purposes where access to parametric features is not required, then data-healing procedures of the sort shown in this Exhibit may be applied. Healing software generally is able to 154