MBD Implementation Dos and Dont's: Trust but Verify - featured in The SOLIDWORKS Blog

 

In 2D drawing oriented manufacturing processes, there is a common step called “drawing review” to check the drawing quality, such as conformance to the 3D model, view layouts, units, callout styles and standard compliances. This review step is vital to establishing the trust into the design communication with internal and external collaborators.

In model-based design (MBD) processes, many practices may change, but such a checking step shouldn’t be ignored. In fact, it should be taken more seriously than in the 2D drawing processes, because MBD is much younger than 2D drawings and many people are not as familiar with MBE as with 2D drawings yet. As a new carrier of critical design information, MBD needs to earn the trust from all the key stakeholders.

Figure 1. A tangent plane modifier added to a parallelism feature control frame is invalid in an ISO-standard document.

 

The review can be done manually, similar to the 2D drawing review process. So I won’t go into details there. In addition, thanks to the progress made by 3D software applications in recent years, many of the checks can actually be done automatically.
For example, SOLIDWORKS MBD can detect GD&T standard compliance issues when the callouts are added and edited. Figure 1 shows that a tangent plane modifier applied to a parallelism feature control frame is flagged as invalid. The reason is that this document standard is ISO and ISO standards don’t support the tangent plane modifier yet.

In other words, the real time GD&T checking can help us improve 3D annotation qualities and manufacturing qualities accordingly. This blog post, “Check Your Grammar: Verification for GD&T and MBD” shared more details of the integrated GD&T rule checks in SOLIDWORKS MBD.

Beyond one CAD application, in manufacturing collaborations, companies often need to read MBD data from one CAD product into a different release or different applications. A SOLIDWORKS partner product CADIQ specializes in validating the derivatives against the source design. Figure 2 shows CADIQ validation results highlighting the differences between the source CATIA V4 model, its CATIA V5 version, the Pro/Engineer import and the Unigraphics NX import. As you can see, the derived NX V5.0 model contained a major shape change on the lid from its source CATIA V4 model. So please pay close attention to the imported MBD data before executing your production based on it.

Figure 2. CADIQ validation results of multiple CAD applications against the source design.