STEP is an established ISO standard (ISO 10303) for exchanging product data between different CAx and PDM/PLM systems. To drive international use of the standard forward, AFNeT, PDES, Inc. and the prostep ivip Association created the Model-Based "x" Interoperability Forum (MBx IF) to serve as a new umbrella organization for the established CAx IF, PDM IF and EWIS IF projects. The objective of the new joint project is to speed up the development of STEP interfaces and ensure that user requirements are met.
The MBx IF is addressing several topics relating to STEP AP242, namely computer-aided design (CAD), product data management (PDM) and electrical wiring interconnection systems (EWIS); the latter is supported by only AFNeT and PDES, Inc. It provides user companies and software vendors with a trusted environment in which to discuss requirements and technical challenges, create a common understanding of the various issues and derive robust approaches to implementation. The new umbrella organization is intended to boost further development of the STEP standard thanks to cross-disciplinary integration. Its responsibilities also include organizing STEP benchmarks.
A key added value of the MBx IF for user companies and software vendors is reliable recommended practices for the cross-domain implementation of STEP AP242. Last year, several implementation guidelines were updated to reflect new user requirements and the most recent changes in the data model. The product structure validation properties defined in the LOTAR project, among other things, were included in the recommended practices.
The XML viewer requirements for the STEP AP242 Domain Model were prioritized at the MBx IF level. The requirements for expanding STEP derived from the "Visual Issue Management" (VIM) use case were handed over to the respective ISO working groups for STEP standardization.
The members of the CAx IF project group have identified new requirements for the representation of product and manufacturing information (PMI), e.g. in model views with multiple sectional planes, and have developed new user stories for composites. This is involves in particular what are referred to as limited length or area indicators (LLAI), which will be addressed in the upcoming Edition 4 of AP242. They have also identified requirements for data classification and the representation of metadata in 3D models and shared it with other project groups in the MBx IF.
With the completion of the 50th round of testing, the CAx IF has demonstrated just how important a functioning implementation forum is when it comes to providing support for a dynamic standard. A major milestone was the successful exchange of kinematic mechanisms between different systems, which was achieved in close collaboration with the JT IF.
The PDM IF project group has conducted a survey that indicates the project participants' satisfaction with the way in which the project works and the high level of use to which the implementation guidelines are put. The survey also allows conclusions to be drawn with regard to the priority of the use cases in the current year and about possible synergies with other working groups.
The PDM IF completed its 13th and 14th rounds of testing. It consolidated the current test cases (alternative parts and the optional use of parts, incremental exchange, product configuration based on individual efficiency gains) and prepared new test cases. In addition, the test cases for alternative geometries and user-defined CAD attributes vs. PDM system properties were prepared for cross-domain testing in the MBx IF. The project group also helped define the scope of the STEP AP242 benchmark planned for 2023 and how it works.
The biggest challenge and success in 2022 was breathing life into the MOU signed in 2021 and ensuring that the MBx IF was operational. The project partners had to define and implement the joint processes and shared responsibilities. They identified cross-disciplinary issues and started work on them.
At the same time, the MBx IF infrastructure was expanded to support all the areas (CAx, PDM and EWIS). All the user groups now use Redmine, an open source tool, to track their requirements. The CAESAR test environment, which is used by all the implementation groups, can be integrated with Redmine and the ISO SC4 Jira instance in order to link requirements, standardization-related topics and associated test results. A joint platform for storing and distributing documents is in the pipeline.
Successful collaboration between the implementation groups, both within the MBx IF and with other projects (e.g. the JT IF), will continue with the aim of providing support for cross-domain integration. The CAx IF will expand its scope of application for kinematics and composites and support new topics, including PMI at assembly level and persistent IDs for design iterations. The user companies represented in the CAx IF will identify additional requirements and speci-fy them in greater detail, in particular for composites, PMI at assembly level and data classifi-cation.
The PDM IF intends to extend its scope of application for typical test cases such as flexible parts, adaptation of object type and properties, multiple identifiers along the supply chain, delta exchange, and the exchange of multiple part versions within a single file. The test cases pre-pared in 2022 will be executed in the next rounds of testing. Users will prepare new and con-solidated ongoing test cases based on the priorities that resulted from the survey. Support for the STEP AP242 benchmark will be provided as needed.
"The close collaboration between AFNeT, PDES, Inc. and the prostep ivip Association has made it possible for us to exploit synergies. Not only did we find a good approach for working on cross-domain topics within the MBx IF, but we also discovered areas for future collaboration with the CAx and JT user groups. Being able to meet face-to-face again has given a huge boost to tech-nical discussions and problem solving."
"Our aim is to collaborate successfully within the MBx IF and with other im-plementor forums, attract new users, include more CAx, PDM and EWIS sys-tems, and expand our scope to involve new industries. A key factor for suc-cess will be obtaining realistic test data from industry. Common test data from different industries that can be used by other implementation forums would make it possible for us to create even more synergies."