A Review of Geometric Integrity Criteria for Military Standards – 31000A

In this article, we focus on the geometric integrity criteria presented in MIL-STD 31000A[7]. We present a general review of the geometric integrity criteria and recommend a method that focuses on the investigation of geometric and topological property violations to identify defects. We propose ways to improve the geometric integrity criteria classes and the recommended correction methods provided by MIL-STD 31000A. We point out how the categorization of the tests based on dimensionality arguments or experimental observations creates repetition in testing. We show that the heuristic checks complicate the testing procedure by letting the designer or the user diverge from investigating the inherent reasons of the invalid geometry. We examine the curve criteria as a local application of our analysis. We highlight that although the tests are defined based on dimensionality arguments, the threshold definitions disregarded this approach, and dependency needed to be introduced over the threshold values of the geometric components of different dimensions. We present how the inconsistencies in thresholds may result in an unintentional creation of a faulty design or allow a defect to go unnoticed during a model validation. We suggest some alternative threshold values for the aerospace and automotive industries’ geometric criteria to eliminate some existing inconsistencies.