面向公差分析的几何尺寸和公差语义信息翻译

For alleviating the error-prone and inefficient process of reentering tolerance analysis specification manually and enabling the tolerance analysis system to understand semantics from upstream product design information, an approach interpreting Geometric Dimension & Tolerance (GD&T) semantic information for tolerance analysis was proposed. The GD&T information that needed to be interpreted was categorized, and the neutral-file-based EXPRESS models were developed. The Web Ontology Language (OWL 2) was used to map those EXPRESS models to corresponding ontologies which laid the reasoning foundation; then rules for automatically inferring the tolerance analysis specification were defined and encoded through SWRL. A plug-in for interpreting GD&T semantic information was developed in a CAD system to extract and import interpreted GD&T semantics into neutral files, and protégé was used to model ontology and rules which infered variation for tolerance analysis. A case study of tolerance analysis for an assembly model was also given to demonstrate the proposed method.