Measuring the PMI Modeling Capability in CAD Systems: Report 3 - Fully-Toleranced Test Case Verification

Abstract

(NIST) has created a test system to measure conformance of Computer-Aided Design (CAD) software to American Society of Mechanical Engineers (ASME) standards for product and manufacturing information (PMI), specifically geometric dimensioning and tolerancing (GD&T) information. The test system has three main components: test cases, test CAD models, and verification and validation test results. The verification and validation results measure PMI implementation capabilities in CAD software and derivative STEP, JT, and 3D PDF files. All of the test cases, test models, test results, and other presentations are available from the project website:

Guide to the NIST PMI CAD models and CAD system PMI modeling capability verification testing results

“…Table 8 and Table 10 show the PMI representation and presentation limitations (errors), respectively, for the CTC. There are other similar verification testing results for the FTC [6]. Table 9 is a key to the abbreviations used in the tables.…”

“…The verification testing of the CAD systems, described in the project reports [4,6], involved modeling the PMI annotations in CTC and FTC (Section 2.2) in the four CAD systems (Section 2.1) as best as possible with a preference given to PMI representation (semantic PMI) over PMI presentation (graphic PMI). The resulting semantic and graphic PMI information in each CAD model was compared to the corresponding information in a test case drawing.…”

“…However, FTC 7, 10, and 11 were not modeled in any CAD system and are not represented in the following figures. Figure 12 shows the distribution of the 297 PMI annotations in the five CTC and three FTC (6,8,9) drawings. In the upper left of the Keshif display are the number of annotations per test case for the five CTC and three FTC.…”

“…Drawings of other views for each test case are provided in Appendix B of the verification reports [4,6] except for FTC 7, 10, and 11. Those test cases were not included in the verification testing.…”

On the integration of model-based feature information in Product Lifecycle Management systems

“…Autodesk Inventor, Siemens NX, Siemens Solid Edge, PTC Creo, Dassault Systems CATIA, Dassault Systems Solidworks) support model-based definition standards such as ASME Y14. 41-2012 andISO 16792:2015. Extensive work on the PMI capabilities in CAD systems (Cheney & Fischer, 2015) has also been carried out over the past few years by the National Institute of Standards and Technology (https://go.usa.gov/mGVm). In this regard, the system architecture and implementation details described in this paper could be applied to any PMI module, regardless of the CAD environment.…”