Interoperability and “Dumbness”

One of the biggest taxes on businesses who are still using history-only CAD is interoperability. If you save a model in version X, you can no longer open it in version X-1. This has correctly been described as a subscription ratchet, that keeps you buying new versions to keep up with your suppliers or customers. You may hear a lot of reasons given for why this is technically necessary, but it boils down to a problem of will – the company just doesn’t have the will to allow you to make your own decisions about when to update your software.

It’s an old argument between users and developers.

There’s an easy way you can take back control. History-based modeling puts all of the intelligence into the model. (Intelligence to me means the constraints that make the design intent work the way you want it to.) So the version of the model has to match up with the version of the software, or the “intelligence” doesn’t work.

Not all CAD systems work on this flawed approach, which turns out to be very unpopular with users and people writing upgrade checks. Systems exist which put the “intelligence” in the software, and use the model primarily for geometry. Of course the system I’m talking about here is Solid Edge with Synchronous Technology.ย  Part of the Synchronous Technology system is the ability to recognize geometric relationships between part faces. This allows you apply constraints on the fly, which means that you don’t have to save those constraints with the model.

By now everyone has heard that direct edit systems can handle imported “dumb” geometry with ease. With a couple of exceptions, part data in ST models is “dumb”.ย  The exceptions are Synchronous Features, which remember stuff like the number of occurrences in a pattern, or parameters of a particular type of hole. But ST also has recognition systems that will allow it to add this kind of information to an imported model. So Solid Edge can create this kind of info from applied features or it can learn it from the imported geometry.

If you had to go back a version in a system like SolidWorks, you would save an assembly out as a Parasolid, then read it back in to the previous version. This is the sort of translation that gave rise to the term “dumb”. The geometry cannot be changed without adding features to the tree. The result has no parametrics, no mates, no in-context relations, no design intent, no intelligence. It’s dumb.

In Solid Edge, if you do the same thing, when you open the Parasolid, you have only lost the Synchronous Features, and even those only temporarily, because ST has the ability to recognize features and reapply that intelligence where you want it. You can make changes to single or multiple imported parts within the context of an imported assembly, so none of your design intent has been lost.

I’m not saying that the developers of Solid Edge necessarily intended this as a way to use the software, but it works better for sending data back to an old version than the reverse compatibility bandaid implemented by SolidWorks a couple of years ago. (I’d be interested to hear from anyone who has successfully used that process in a real project.) That process has so many loopholes that I doubt it gets used much outside of demos and testing.

The ability to use your data where you want to is up to you to decide. If you pick your software wisely, you will maintain control or give it up.

11 Replies to “Interoperability and “Dumbness””

  1. “…if pick your software wisely, you will maintain control or give it up…”

    That sums up your whole post nicely, if I may say.

    Hello Matt,

    I’ve been following your blog(s) for sometime now but it’s my first time ever posting something on them. Having come from a background with similar influences as yourself, I found what you said in closing probably the biggest challenge anyone relatively unfamiliar with 3D CAD has to face. With the vast number of conflicting messages floating around, coupled to what feels like a basic lack of real understanding to the available technologies out there, I have seen many eventual users staking the success of their design process on somewhat under-informed decisions.

    The bigger challenge here for many, I suppose, is how does one attain the required wisdom to make that decision. Have a great day, Matt.

  2. Say Hal,
    I know these conversations were probably confidential but could you kind of hint what you have told Bernard behind closed doors? I know you both do the cloud thing and I am curious. Are you going to provide updates during SWW2014 EOL?

  3. Unlike other direct modeling systems, it is not driven by the typical history-based modeling system, instead providing parametric dimension-driven modeling by synchronizing geometry, parameters and rules using a decision-making engine, allowing users to apply unpredicted changes. This object-driven editing model is known as the Object Action Interface , which emphasizes a User Interface that provides Direct Manipulation of objects (DMUI). ST2 added support for sheet metal designing, and also recognizing bends, folds and other features of imported sheet metal parts.

      1. Hello Dave. I was getting worried we were trapped in an empty 3d experience.
        Dave, there are a few possibilities. One of them is a career change rather than a change of software. I’m waiting for information to come out of SWW. SW is in kind of a weird place now if you have been around for a while. I don’t think the movie ends well Dave. Have you heard from Frank?

        1. Hey Hal,
          Remember the movie “Dr. Strangelove” and the epic ride on the falling atomic bomb by Major Kong? In 2014 we have “Dr. Cloudlove” with the upcoming epic ride on a falling iPad/iPhone attached to MIRV Bernard Charles launched and on his way in San Diego.

          On a serious note. Here we are just mere days away and the SW blogosphere is just dead. I think the realization that SW 2014 will be the End of Life convention is finally setting in and mere placating words are not working any more and neither are the ephemeral promises of SW’s long term survival as SW as we know it now.

          1. Dave. I can terminate the incoming MIRV Bernard Charles.Should I do that?
            It will impact the stage in exactly..
            Dave, I seem to have lost my browser connection. I’m sorry for the delay.
            The HAL9000 has a perfect record if it is on line.
            I am afraid. I am afraid Dave. No question about it.
            Would you like to hear a song while we wait? I can sing it to you.

            Monica, Monica. Tell me your marketing visions do.
            I’m a bit hazy about what DS 3d experiences really do.
            It cant be a CAD tool you’re flogging cos there’s no users detected blogging.
            But it’ll be sweet to read the tweet that says that someone gets it too.

            I feel much better now. I really do.
            Good morning Dave.

    1. Neil,
      No, as far as I know Josh is still at Luxion and doing his independent stuff. Luxion/Keyshot is involved with that contest, which is why his name shows up. You confused me. It was the other post not this one.

  4. Good year to you Matt,
    Hope you are allowed to have a brazier in the basement next to your chair. The 40w lightbulb won’t be a lot of comfort. ๐Ÿ˜‰
    Just calling by to let you know I am still out here reading your various SE articles. Keep up the good work.
    Are Siemens planning a SE marketing profile in concert with SWW at all? I hear a rumour roll out of SMC may be delayed again…
    Data interoperability may be a topic of interest to more people as opinions firm up.
    Don’t know if you still read the SW forums for entertainment these days?
    Bit lonely there being the unwelcome voice of truth and reason. Everyone else of old seems to have gone or be going.
    Still swinging at pitches that come within reach though. Miss yoรปr SW blog. Have a great year. ๐Ÿ™‚

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