PDT standard development workbench

The development of an international Product Data Technology (PDT) standard is a major endeavor. Current project time-frames ó excluding international review resources ó are estimated to 2 ó 4 years employing 4 ó 6 people full-time. However, the time schedule often fails as a result of the need for international co-operation, agreement, extensibility, and portability of the standard, and ó more importantly its subsequent implementation.

By introducing an electronic workbench through capable software tools the time and costs associated with the development work may be reduced by up to 40 per cent. (Source: National Institute of Standards and Technology, 1998).

PDT standards, with the product model as its nucleus, include all aspects of defining and processing information pertinent to a product throughout its development and operational life.
Albeit the EXPRESS Data Manager from EPM Technology primarily targets application development and integration, its generic handling of EXPRESS schemas and their instances has proved to be a very efficient workbench for PDT standard development projects by supporting data modeling, test suites development as well as validation of metadata, instances, and implementations:

• Data modeling ó EXPRESS Data Manager defines application objects and their attributes, constraints and descriptions. EDMvisualExpress provides a consistent view of all information, and the EDMexpressCompiler ensures that the EXPRESS data model is correct. The content of the data model can be reported as EXPRESS source code, an SDAI dictionary model or as various text formats.
• Data constraints/validation óto serve a specific business purpose it is important to constrain data, for example by specifying data types, value ranges, and applicable conditions. The EDMmodelChecker is capable of checking all constraints defined in EXPRESS. It is not only a powerful tool for assuring the quality of data to be exchanged between different parties, but also a debugging tool of executable statements that are used within the model.
• Data prototyping ó as part of a standardization project it is important to provide test data for checking conformance of implementations. EDMinstanceBrowser and EDMp21Handler included in EDMdeveloperSeat provide features to populate the EXPRESS model with test data to be used for application conformance testing. Again, the EDMmodelChecker proves to be a valuable tool to keep such data consistent with the underlying data model, particularly as it evolves over time.
• Mapping ó in a layered data architecture, mapping/projection between different data models is needed. In a STEP data architecture there would be one requirement model (ARM) that maps to a new model conforming to the integrated resources (AIM). By using the EXPRESS-X specification, the EDMmodelConverter makes the access to information transparent; in other words, the conversion between the models is provided as a service by the system.
• Inter-operability with other tools ó in most cases, and this is the very reason for developing IT standards, one tool cannot do everything. With EXPRESS Data Manager all data can at any time be accessed using the STEP implementation standards ISO 10303-Part 21 and ISO 10303-Part 22 in addition to the defined text formats.

  Given the large demand for resources to develop a PDT standard ó including the reviewing and standardization procedures ó projects will benefit from the use of a product model driven environment.

Current standardization projects that use EXPRESS Data Manager for the above mentioned tasks are: ISO 15926 (Oil & Gas); CIMsteel Integrated Standards (CIS and AP230); DNV (Ship in Operations); EMSA and MariSTEP (The Ship Building Blocks AP215, 216, 217, 218, 226); and STEP (AP210, 232), ISO TC211, CEN TC287 (GIS), IAI (IFC).