Exchange Model-Based Definition (MBD) Datasets Using SOLIDWORKS MBD 2018

Oboe Wu | Comments | October 6, 2017

Suppose I am a supplier using SOLIDWORKS to support large enterprise clients across the globe such as Airbus or Boeing. In a typical job, my clients send 2D drawings only or 3D models plus 2D drawings to convey their design requirements. I read the drawings to understand the sizes, critical tolerances or surface finishes of the job. I import the models into SOLIDWORKS and pan, zoom and rotate the models to comprehend the 3D topology and structure. Then I provide a job quote based on the drawings or the 3D models.

However, things are changing these days. My clients no longer send me 2D drawings. Rather, they send me only 3D models—either native or neutral formats integrated with 3D annotations such as datum symbols, dimensions, tolerances and surface finishes. These models may be in non-SOLIDWORKS formats such as Creo, NX, CATIA V5 or STEP. Now, what should I do? These annotated models look like black boxes to me. I may be able to import the models into SOLIDWORKS, but the key requirements conveyed in the 3D annotations will be missing. How am I supposed to provide a job quote without knowing the requirements of the job? Do I have to buy, install and maintain one seat of every proprietary CAD application just to see the annotations my clients provide? What about the neutral STEP files integrated with 3D annotations?

It turns out that this situation is not unusual. More and more suppliers are reporting similar situations driven by large enterprises moving toward model-based workflows. As suppliers, you really don’t have any choice but to adapt. Therefore, it’s encouraging to see that SOLIDWORKS MBD 2018 now imports both models and 3D annotations from Creo, NX, CATIA V5 and STEP242. Figure 1 shows an NX model integrated with 3D annotations that has been imported into SOLIDWORKS.

Figure 1. An Imported NX model integrated with 3D annotations and views inside SOLIDWORKS MBD 2018.

You may notice that the annotations highlight the associative features. For example, the positional tolerance feature control frame in green highlights the width feature of the pocket on the plate. This helps you to visualize and confirm the relationship between an annotation and the defined feature as is recommended in the ASME Y14.41:2012 standard. Furthermore, the NX model views are brought in at the bottom 3D View pane, which can improve your visual understanding of all the requirements, which can be overwhelming sometimes. You may examine one view at a time, or follow the curated views to look at certain details in a sequence.This way, the annotated models don’t look like black boxes any more. Even without 2D drawings, suppliers using SOLIDWORKS MBD 2018 can obtain the key requirements conveyed in a model’s 3D annotations.

One caveat is that the imported annotations are graphical only, so while human eyes can read them, the software applications are unable to provide additional semantic meaning behind the graphics. This is one way that the software can be improved in the future. Ideally, the semantic definitions would be retained after the annotations are imported into SOLIDWORKS, in order to automate downstream applications such as machining and inspection. This type of tolerance-based automation is possible today with native SOLIDWORKS annotations as illustrated in this blog post.

Another use case is that after the model is imported, engineers would like to create 2D drawings or publish 3D PDF documents based on them. In the 2018 release, these imported annotations don’t show up in these derivatives yet, because the annotations are not native to SOLIDWORKS. This is another area that can be improved in the future.

Now, besides the annotation import, what if a manufacturer needs to export annotations? A typical scenario is that a designer using SOLIDWORKS needs to send a neutral STEP file to a machine shop that may not have the software installed. To facilitate the advancement of the model-based workflows, in 2014, ISO released a new STEP standard, ISO 10303-242. I’m glad that SOLIDWORKS MBD 2018 can now export semantic or software-readable annotations in this neutral format as shown in Figure 2.

Figure2. A STEP 242 file exported by SOLIDWORKS MBD 2018.

The model is displayed in eDrawings 2018. As you can see, selecting the feature control frames on the bottom face, or datum feature A, highlights the associated feature in green.

To illustrate the semantic definitions behind the graphics, Figure 3 shows the analyzed results of a SOLIDWORKS MBD STEP 242 export using the STEP file analyzer by Robert Lipman with the National Institute of Standard and Technologies, or NIST.

Figure3. The analyzed results of a STEP 242 file exported by SOLIDWORKS MBD 2018.

As you can see, the datum references, dimensions, tolerances, geometric control symbols, modifiers, and other annotations are conveyed in their semantic definitions. This makes the information consumable by the downstream manufacturing software applications. Therefore,various automations can now be realized even without native CAD models, such as Computer-aided manufacturing (CAM) for machining or coordinate measurement machine (CMM) for inspection. It will take some time for manufacturing software venders to fully digest and act upon the semantic annotations in STEP242, but it’s promising to see that SOLIDWORKS is taking the lead to lay the foundation for the digital information flow.

It’s important to acknowledge that even before CAM software can act upon the intelligent annotations in STEP 242, just seeing the annotations attached to the model in one place provides remarkable value. Typically, a machinist loads a model in a CAM program, but they have to navigate through multiple pages of 2D drawings outside of the CAM program to collect the tolerances or surface finishes. Then the machinist must go back to the CAM environment and key in these requirements. Now, being able to see everything in once place means that machinists don’t have to switch back and forth between 3D models and 2D drawings any more, which is a significant time-saver today.

Of course, a natural next step is for CAM software to automatically extract the requirements attached to the STEP 242 models and program machining strategies, setups, and numerical control (NC) code accordingly. This automation has been realized with native SOLIDWORKS annotations by SOLIDWORKS CAM. I’m sure the automations based on the neutral STEP 242 are coming soon.

With that, let’s quickly recap this article. To facilitate the collaboration in Model-Based Enterprise (MBE) workflows, SOLIDWORKS MBD 2018 added the capability to import non-SOLIDWORKS annotations and also to export software-readable annotations in the neutral STEP 242 format in compliance with the ISO 10303-242 standard.

If you have any comments or questions, please feel free to leave themin the comments area below. To learn more about how SOLIDWORKS MBD can help implement your Model-Based Enterprise, 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.

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