Big things are quietly happening in the aerospace industry, related to 3D model-based definition (MBD). We are talking about what can become a key step in the aerospace & defense industry’s transition from paper-based documentation of product development to 3D model-based representation. As it is now, for example, the authority-related certifications are mainly based on paper documentation, while the aerospace industry has long since switched internally to working with digital 3D models. This is not an ideal relationship.
Today, this discrepancy has been met by some interesting work. In a recent report, the Aerospace & Defense PLM Action Group (A&D PAG) has developed a 3D Model-Based Definition solution for Type Design Certification, containing a list of their detailed requirements for the minimum data items required.
“It’s time to move forward towards the goal of retiring drawing-based concepts,” says Brandon Sapp from Boeing Enterprise Engineering. He has also been technical leader for the A&D MBD working group over the past year.
Dr. Ken Versprille, executive consultant at CIMdata, which administers this important group, agrees. “These detailed requirements represent a watershed milestone in CAD,” he says. “We know of no other industry that has collectively documented their agreed-upon detailed MBD requirements. The effort provides both standards bodies and solution providers alike a road map for their future efforts in data exchange.”
A Group Whose Words Hold Weight
What the A&D PAG has to say about product development work in today’s highly exposed aerospace industry is of utmost importance. The group was founded in 2014 and today consists of leading OEM manufacturers such as Airbus, Boeing, Bombardier, Dassault Aviation, Embraer, GE Aviation, Gulfstream, Rolls-Royce and SAFRAN. The goal of the A&D PAG is to strengthen its influence with the larger PLM suppliers and relevant authorities in order to be able to take action against troublesome product and process shortcomings.
In the recently announced report, the group presents its detailed minimum requirements for data objects, which are required for type design certification in connection with standard 3D model-based definition (MBD). The requirements are the culmination of two years of work from the team, which consists of domain experts from the eight members and selected Tier 1 suppliers.
The study documents use cases and definitions regarding MBD at OEMs. The list of requirements that has now been produced contains over 200 specific data items that are needed in a 3D MBD model for aircraft.
Gap Analysis Defines Differences with Open Data Standards
This list will in turn be used in analyses where differences between different open data standards are highlighted, a so-called gap analysis.
This type of analysis is generally a method of assessing the differences in performance between a business' information systems or software applications to determine whether business requirements are being met and, if not, what steps should be taken to ensure they are met successfully. In the process, the actual performance or results are compared with what was expected or desired.
Without being limited only to these, in the case of A&D PAG’s work we are talking about cross-checks towards standards such as ISO 10303-242 (STEP AP242), ISO14306 (JT) and ISO32000 / 14739 (PRC for 3D PDF). Specifically, those standards used to support data exchange and interoperability requirements for existing MBD design processes. The stated goal is that each of the industry standards should support the requirements equally, and that all solution providers that provide a tool for data exchange of their own formats to the specified standard formats should do the same.
By using this method to provide ways to identify suboptimal or missing strategies, structures, capabilities, processes, practices, technologies or skills, steps are recommended that will help to meet required goals, asserts Dr. Versprille.
Basic for Digital Threads
One interesting aspect is that the A&D PAG members believe that 3D MBD is fundamental to digital thread strategies.
Sapp commented, “As information captured within an MBD continues to grow and CAD authoring tools continue to improve their integration with the digital thread, a specific focus on how the information is represented is needed. The research in this paper is the first step in defining the semantic requirements of that information with the goal of retiring drawing-based concepts.”
This is a weighty statement from someone who has more than 22 years of experience in engineering. Sapp led the Design Methods team through the implementation of Model-Based Definition throughout Boeing Commercial Airplanes. Currently, he is leading the way for Boeing’s strategy on the use of data standards and interoperability across the enterprise. Brandon is a member of the US TAG to ISO TC 184/SC4 and the newly formed ASME MBE committee. He leads working groups at AIA’s Business Technology and Interoperability Committee, and he is also the Deputy Chair of the Technical Advisory Committee and Co-Chair of the CAx-IF User Group at PDES.
“Part of our Boeing and Aerospace work is to enable the Model-Based Enterprise (MBE). Part of that is certainly MBD. By exposing the key information requirements in the MBD and moving away from “drawing based concepts,” we can enable that linking to MBSE (Requirements, Logical, Functional), MDAO (Multi-Disciplinary Analysis and Optimization) and downstream to metrology and cyber-physical automation. It’s the linkage and the digital thread we are focused on. Exposing and upgrading how the information is represented in the MBD is a big enabler of that vision,” said Sapp.
Concretely, there are some significantly important results in the work. Brandon Sapp points at how they in the group discussed the use of flag notes/annotation notes.
“This concept was designed to move engineering requirements from the face of the drawing and define them in a separate artifact, for example BOM, Parts Lists and separate drawing sheet,” he said. “The benefit was that cleared up the drawing to show the geometry and related dimensions/tolerances (especially when there were multiple instances of the requirement). It also allowed for the requirements and notes to be consumed in the ERP systems.”
Sapp added that technology is at a point now where requirements can be directly applied to the feature without it clouding up the 3D scene. “We now have the ability to expose that information into the PLM system for interoperability, part ordering and data warehousing. By doing this, we can enable users and systems to directly access the information without having to go to a separate system to obtain the information through implied naming conventions and IDs that have to maintained.”
How is the work presently being used?
“The research by this team is being used to drive improvements in the industry implementations. Current activities in the CAx-IF (Interoperability Forum) can be directly traced to the work here by this team. Industry implementations benefit not just the OEMs. The entire supply chain can now have access to capabilities to create and consume data that can be trusted without driving huge software costs,” Sapp asserted.
“This is a big milestone for the A&D Community,” Sapp concluded. “I hope this research can be used to drive some changes in the standards community and related implementations.”
Positive Signals from Standards Developer
From Eurostep, the developer of standards-based solutions, comes positive signals about what is happening now.
“As a developer of collaboration software ShareAspace, my view is that what the CIMdata A&D PAG produced will be important as a step to extend the digital thread across company boundaries. We need to move away from the document paradigm as this is not using the power of digital transformation currently taking place,” says Håkan Kårdén, founder and marketing director at Eurostep. “With the type of design system that exists today, it is not always possible to produce a document/drawing. New types of business processes, smarter and with less friction, are enabled and must be supported also by different authorities.”
Guidelines and Research Reports Can Be Downloaded
Since 2014, A&D PAG—administered by CIMdata—has sponsored research and jointly staffed projects on a variety of priority topics in industry and technology. These topics include model-based definition, multiple-view BOMs, PLM technology obsolescence management, global collaboration and model-based systems engineering (MBSE).
As a result of these investments, A&D PAG has released a series of guidelines and research reports that are freely available for download from the website www.ad-pag.com.
Providing these materials is in line with the group's mission to engage proactively within the PLM ecosystem and advocate joint management and positions in the aerospace and defense industry on PLM-related topics that are important to funds.
“As Is” and “To Be” Approaches in the Paper
Why is “Minimum Model-Based Definition (MBD) for Type Design Certification” important to the aerospace and defense industry? There are several reasons, but the overarching one is that multiple and ever-changing engineering and manufacturing software tools used to design and produce a product add time and cost by requiring data representation changes to maintain a current definition of the product.
The new paper produced by the action group captures the list of minimum data items required for standard MBD.
Dr. Versprille notes that the paper identifies the necessary part types and data items within each that are needed to develop, build and certify the product.
There are two steps in the approach: the paper first presents use cases “As Is” today without model-based definition support, including the business impact. Then it lists “To Be” (desired state) use cases once minimum MBD requirements are met, including the business benefits.
Notably, there is CAD model support related to this paper that will be available later on the CIMDdata website in the future.
My take is that the A&D industry has been prepared to deliver 3D MBD for a long time. An aspect of A&D PAG’s recent MBD paper is that it represents a step to pave the way for digital threads, and also to bring certifying authorities deeper into the 3D MBD world.
It will be interesting to follow the progress here.