We introduced the MBD history and successes at Gulfstream, a subsidiary of General Dynamics, in a previous article. Its achievements are impressive. For example, its model-based definition (MBD) system was the first one certified by the U.S. Federal Aviation Administration (FAA) to design an aircraft. It reused the Gulfstream G650 model MBD data in the G500 and G600 models, so that the two models were designed concurrently and had test flights announced at the same time in early 2015. Gulfstream reduced the barrel joining time from three and one-half days to 15 minutes and cut the part numbers at the airplane completion step by more than 50 percent.
However, the bigger point of this article is not to detail how great these achievements are. It is to describe how Gulfstream did it. You will see that the Gulfstream approach is not out of reach for other manufacturers. You can do it too, although it does require the mindset shifts, process upgrades, continuous trainings, multiple iterations and hard work.
Dan Ganser, product lifecycle management (PLM) staff scientist with Gulfstream, shared an important realization at the CIMdata PLM Road Map for the Aerospace and Defense Industry in 2015. MBD doesn’t mean to put everything in the model. Although, geometrically speaking, Gulfstream models everything, including even the tiny fasteners and thin veneer, using CATIA V5, it doesn’t actually annotate its models with dimensions unless there are special needs to explicitly call out critical dimensions. Tolerance standards are stored in its product data management (PDM) system and it only calls out nonstandard tolerances in the models. Similarly, other attributes such as notes, materials and surface finish processes are stored in the PDM system. This way, the upstream designers and engineers can focus on the truly exceptional characteristics, rather than wasting time in repeating the information already conveyed by the models or PDM system, which also avoids the traditional information conflicts that can occur between 3D models and 2D drawings.
To support this minimal annotation strategy, Gulfstream equipped all of its shop floor technicians with the workstations and CATIA V5 software shown in Figure 1. Technicians are required to measure the models and query the PDM system to obtain what they want. Initially, the implementation team was concerned about whether the shop floor team members would be able to proficiently learn the hardware and software, or whether they would be willing to adjust to this change from 2D drawings at all. It turns out that Gulfstream underestimated how quickly the technicians would adapt to the MBD process according to Jeff Kreide, vice president of Business Solutions with Gulfstream. The workforce is much younger than before. Not only did the workers like the cool technology, but they also grasped the skills needed for their particular jobs much faster than expected.
Figure 1. A shop floor technician uses a workstation and CATIA V5 software to obtain necessary information for the job at Gulfstream. (Image courtesy of Gulfstream.)
Speaking of software, Gulfstream invested thousands of CATIA V5 licenses for every internal member who need data access and also requires all external suppliers to use the same software at the same version, revision and even service pack as it uses. A software upgrade occurs every two years at the end-of-year time frame when all Gulfstream’s internal computers and its suppliers must upgrade together to the same minor revision. In other words, the entire extended enterprise is standardized and synchronized on one engineering software platform. “I can’t tell how big of a difference it has made to the [MBD] implementation,” said Ganser. “Not having to convert data is unbelievable.”
Beyond models, Gulfstream stores a large amount of information in the PDM system mentioned earlier. For example, the assemblies are defined by PDM structure links and the geometric positions are modeled in CAD. Previously, it would take a bill of materials (BOM) planner five weeks and five tries to figure out all the parts that the procurement team needed to buy. Now, thanks to the data structure in the PDM system, anybody with the PDM access can pull up the BOM table in five seconds anytime they want. Furthermore, everyone on the shop floor can access the manufacturing execution system (MES), which is linked to the PDM system, so that a technician can query the PDM system or pull up the models in CATIA V5 for a particular task such as planning and assemblies. Regardless of the task, every geometry traces back to the CAD models and every attribute traces back to the PDM system.
Another big reason for heavily integrating the PDM system was to collaborate with suppliers. Ganser recalled, “When we told purchasing they have to open a model to find the material, it didn’t go well.” When suppliers quote parts, they need the BOM tables, complex finishes, exceptionally tight tolerances, overall sizes and so on, because these are the key drivers of costs. Suppliers don’t even care much about CAD geometries for quoting unless it’s a highly complex part. With the above attributes defined and organized in the PDM system, the procurement team can extract the key information for suppliers in real time without having to open up a model in CAD software. All the PDM information is version controlled and protected with access right management tools.
Now let’s summarize this article into experiences and benefits.
| Experiences | Benefits |
| Call out only exceptional annotations | Focus on critical characteristics and save time |
| Equip the shop floor technicians with workstations and CAD software | Interrogate models and PDM systems on demand |
| Standardize the engineering software platform on the same service pack throughout the extended enterprise | Avoid data losses caused by the CAD format conversion; collaborate with suppliers more efficiently |
| Integrate with the PDM system | Extract on-demand BOM tables and other key data quickly; collaborate with suppliers more efficiently and enhance information traceability |
Finally, an important point to highlight is that the above measures must be part of a concerted effort because they rely on each other to succeed. For instance, if the shopfloor technicians didn’t have the necessary hardware or software to interrogate the CAD models, then the minimal annotation practice wouldn’t work at all. Or if the designers didn’t assign correct attributes to a product in the PDM system, the procurement and suppliers wouldn’t be able to extract the relevant information quickly. This is the reason why MBD implementation needs an enterprise-level perspective and must be well-coordinated and driven from the top down with strong sponsorship from an organization’s leadership. To learn more about how SOLIDWORKS MBD can help you with your MBD implementations, please visit its product page.
About the Author
Oboe Wu is a SOLIDWORKS MBD product manager with 20 years of experience in engineering and software. He is an advocate of model-based enterprise and smart manufacturing.