I remember back when I came into the industry, back in 1995, CAD standardizations ruled. OEMs at the top of design chains carried huge power in selecting a CAD application and then requiring their suppliers to deliver 3D models to them in that format. OEMs that switched their standard from one CAD application to another was like a tectonic shift. It had implications across the industry and was ballyhooed as a huge win.
Today we still see some big press releases and announcements that are framed as earth shattering events. But with all the recent changes in the CAD industry I’ve found myself pondering some, at least to me, a couple of interesting questions.
What are the advantages of standardizing on a CAD application?
Is there still a need to standardize on a CAD format in today’s design chains?
And because of some new technical capabilities that have emerged in the CAD industry over the past few years, the answers to those questions, at least in my mind, have changed dramatically. What follows are those capabilities that I think have changed the answers to those questions. Read on.
Accurate Geometry Exchange
In the past, geometry exchange wasn’t always, to put it in a word, accurate. First off, because different CAD applications used different geometry engines, they used different accuracies. And when a model moved from one to another, well, some freedoms were used to interpret that geometry. Second, the geometric exchange of models between CAD applications weren’t always clean. Sometimes faces or other surfaces of a solid model were simply gone. All in all, it made for quite a gamble.
But today, the story is quite different. Not only has translation standards such as STEP improved greatly, some software providers, such as PTC with their Creo portfolio, are merging their visualization technologies into their CAD portfolios. This enables these visualization-CAD applications to natively read files from a wide variety of other CAD applications.
Geometry Changes No Longer Require Features
If you think back, years ago, about the motivation to pass native CAD files back and forth, the rationale was pretty simple. The only practical way to modify the CAD model’s geometry was by manipulating its features. You could use the dimensions or parameters within the features to make changes. If you exchanged a neutrally formatted file instead, after importing it, you were left with an explicit model that basically was a dumb piece of geometry. All the model knew was its geometry definition, not the features that were used to make and drive that geometry.
Fast forward to today and that story has changed dramatically. Direct modeling approaches, which are popping up in just about every CAD application today, allow users to push, pull and drag geometry without the need of features. Furthermore, you can use dimensions and parameters to make controlled changes to geometry. So do you need a native CAD file anymore to make geometric changes? Not really.
Decoupling Design Intent from Features
Another historical reason to exchange native CAD files has been to access relationships embedded within the model. You were and continue to be able to drive values of dimensions and parameters of features through equations and logical statements (if, then, else) that involved other dimensions and parameters. These types of relationships enabled a CAD model to automatically adapt and change to other modifications. It essentially enabled users to embed design intent and intelligence into their models.
Skip forward to today and that story is starting to change. Some CAD applications allow users to build these types of relationships outside of the context of features. Solid Edge calls them live rules, notably because they are live during direct modeling dynamic changes. Spaceclaim does something similar. But the idea is that, at least in some of these CAD applications, relationships are now being decoupled from feature definitions. Now, that’s not to say that they can be imported as part of a STEP file. I am fairly sure that can not happen today. But it is in the realm of feasibility. Of course, the old barrier to doing so is likely the software provider’s willingness to actually do it.
Cultural and Training Barriers Remain
Back in the day, users of specific CAD applications were vehemently loyal. Arguments, live and online when it came available, would erupt over which CAD application was the best. Organizations with fanatically dedicated users, of which there was always at least one, faced a serious challenge if they decided to switch their standardization from one CAD application to another. But beyond the cultural pushback, there was a very real challenge of training (or retraining) these users to use the new software.
Today that concern is still real, although not nearly as high of a barrier as it used to be. The past ten years in the industry has been filled with efforts by almost every software provider to make their CAD applications easier to use. And that effort has helped tremendously. Interestingly enough, some software providers have even pushed harder. Spaceclaim, for example, has no formal training for their CAD application and relies on the intuitiveness of the software and online support materials. And in fact, based on a survey they ran recently, somewhere close to 50% of their customers say they ‘just picked it up’.
Conclusions and Questions
So where does this all leave us? In my opinion, many of the old reasons to move towards a CAD standard are evaporating: there’s little need for it anymore. Sure, getting and accessing the embedded relationships in models in the context of a supply chain is important. And sure, there would be cultural pushback and some training issues if an organization did move away from a standard. But many of the old motivations, specifically geometric accuracy and native modification through features, are losing their relevancy in terms of why to stay standardized.
Well, I emptied my head on this topic. Mostly that is. I’m sure you have some thoughts. Drop them in the comments section. I’d love to hear any and all perspectives.
Take care. Talk soon.
