What Exactly Is Creo? – Part 3

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In the first part of this series I mentioned that you could open a history based parametric model in the Creo direct modeling application, trash the model around, open the trashed model in the Creo history based parametric modeler and the feature tree would be automatically modified. This sounds a lot like what Autodesk is doing with Fusion. But is it?

Take a look at this video. Please bear with the dropped frames. I captured this video from my web meeting with Mike Campbell. I’ll try and post a better video later on. The video shows a history based parametric model opened in the direct modeling application. First the user moves a part of the model by dragging a few faces. It seems like a simple modeling operation, one that could have been done on the history based parametric side itself. Next he picks a complicated part of the model containing a bunch of features including patterns and drops it on to a different side of the model. If you had to do this in the history based parametric modeling application it would definitely involve a lot of time and work. Finally the user drops a rib feature from the library onto a face and patterns it.

Next, the model is saved and is opened in the Creo history based parametric modeler which recognizes that the model has been modified by the Creo direct modeler. It queries the geometry and lists the changes for the user to accept or reject. This is similar to what Autodesk has done with Fusion. The user rejects the first change and accepts the other two and the feature tree is modified accordingly. The user then moves the complicated part of the model that was moved in the video above using history based parametric modeling. Finally the user redefines the rib feature and regenerates the model to propagate the changed rib through the rib array.

I’m not sure, but there seems to be a slight difference in the direct modeling approaches of Autodesk and PTC. In the case of Autodesk, the ChangeManager in Inventor has the next to impossible task of editing existing features or cooking up new features. I say next to impossible because in the example above, modifying the existing feature tree to move the complicated bunch of features to another face would be a very difficult thing to do for a human, let alone a piece of smart software. When the ChangeManager fails to edit the feature tree properly, it either messes up the model or adds all kinds of sculpt features to it. In the case of Creo, I am told that existing features are modified only if the resulting geometry yields the same results as the direct modeling operation that caused the feature to change. Otherwise the feature is left as it was before the direct modeling operation and a flexible move feature is added to the bottom of the feature tree. So from what I understand, this is like the software thinking and working like a human. If the change appears to be easy enough to incorporate, the software picks apart the feature tree and adjusts the sketches, parameters, constraints, dimensions, etc. Otherwise it uses the hack and whack approach and adds a move face kind of a feature to the bottom of the tree.

Another thing. If you want to use the Creo history based parametric modeler only and not bother yourself with jumping back and forth with the Creo direct modeler then direct modeling type of operations are made available in the Creo history based parametric modeler as well.

Now, I urge you not to take the above as gospel truth. I have not played with the software yet. This is how it was explained and shown to me. I intend to verify all of this and more if and when PTC gives me access to Creo. Videos are good. But they don’t tell you the whole story. I will be able to make a true comparison between Fusion and Creo only after I have used the software.

There is a lot more Creo. For example, you can use the Creo viewing application (formerly ProductView) to read models from other CAD systems and be able to edit them using the Creo direct modeling application. Then there is the PLM aspect of Creo that I haven’t gone into. With Creo PTC has introduced the idea of creating configurable products without the need of going to the trouble of creating the geometric configurations for them. I have only written briefly about the geometry creation and editing part of Creo that interests me.

So what do you think? From what you have read here, has Creo lived up to the hype created by PTC? Will is transform the CAD marketplace for the next 20 years? If you ask me, it’s really difficult to say until I have used the software and experienced it myself. I like the fact that PTC has unified the user experience across Pro/ENGINEER and CoCreate and broken them down into bite size chunks. I like the fact that Pro/ENGINEER and CoCreate will share a common data model. All that is good. But before I make my opinion on all of this, especially the direct modeling part of Creo, I would like to use the software myself. I don’t know about you, but I just can’t bring myself to get excited by seeing a bunch of videos alone.

Part 4 >>