Monday, December 22, 2008

2008 - The year of Direct Modeling?

I started out this year as an independent consultant doing design and engineering work.  I also did some process consulting for a few manufacturing companies, and even some consulting for some software companies as well.  As an independent I was able to get exposure to a variety of different design tools, CAD and CAE.  It was a good year for this as technology continued to move at a great pace.

During my time as an independent, SpaceClaim came to market (almost 2 years ago now).  I had much fun with that product. They’ve done a nice job at making history-free b-rep modeling simple, fast and flexible and they continue to be a strong advocate for this direct history-free technology.  They seem to be focused on a complimentary, or coexistence strategy and getting CAD into the hands of the non-experts.  In 2008 SpaceClaims’ unique user interaction model and geometry interaction methodologies were “leveraged” by another CAD company, bringing further validation to their place in the industry.

Just prior to 2008, PTC acquired CoCreate, adding direct modeling to their suite of products and raising the awareness again for history-free direct, or as they call it “explicit” modeling.  I watched this closely as I used to work for CoCreate.  Back then PTC was of course our biggest competitor.  CoCreate Modeling remains to be the most matrue and capable of the history-free direct modeling systems on the market - after all they were developing it inside of HP long before CoCreate, the company, existed.

Then came Siemens and Synchronous Technology.  It was great to see all the new attention, again, on history-free modeling.  The marketing buzz from Siemens was that they were the first to combine history-free modeling with a synchronous constraint solver.  Although they weren’t the first, they certainly made some good progress in integrating the two technologies in a useful way.  I still think they have a long ways to go to bring maturity to their history-free modeling environment and the intelligent model, but they certainly have a good start.

There were also many advances this year in direct editing within the history-based environment.  Most all of the history-based CAD vendors now have this capability.  It’s seems a little flakey tracking direct edits in a history tree, but it does further validate the need for more flexibility in our 3D CAD tools.

Now we have Autodesk getting into the fray with Inventor Fusion, another validation that this is where we are heading with regards to 3D CAD.  I still can’t tell what this thing is though.  The demos that I have seen are very trivial and simple, but they do present some nice user interaction tools and methods.  So, is this a history-free CAD tool, or more direct editing within a history-based system, or some weird combo-deal?  Hard to say so far.  I suspect a new history-free environment that will strip away all the history and parameters of an Inventor file, similar to that of SE ST and NX6 ST.  We’ll find out soon enough.  They do show some nice new user interaction concepts and tools. 

While I enjoyed my time as an independent consultant, this last June brought a significant change for me in that I took a job with PTC.  So now I can no longer claim to be one of those “credible independent consultants”.  I guess I’m now a pesky “software vendor”.  It’s been a bit of a strange transition for me.  Not that I haven’t always been a bit bias to history-free modeling, and specifically the CoCreate product, it’s just that now I’m supposed to be. J  I still hope I can be more factual than salesy though.  I think that once someone knows the facts and knows their process and user requirements they will be able to make the right alignment with technology.  History-free modeling is not the answer for all design requirements.  (Not yet anyway).

So what’s coming next year in the world of history-free or direct modeling?  You know, now that we have a few more capable history-free tools out there, we could greatly reduce the interoperability issues that come standard with history-based tools.  Models can now be fully editable across several different CAD tools.  The next step is to be able to transfer history-free features, 3D annotation and parameters between these systems.   The STEP protocol actually has much of this built into it already.  Imagine transferring fully parameterized, intelligent, editable parts and assemblies from one CAD system to another via STEP.  Could it be possible?

Merry CHRISTmas and Happy New Year!!



Jeff Waters said...

Really enjoying your posts. Keep up the great work!

R. Paul Waddington said...

Always an interesting and informative read your blog Paul.

Thank you, and a merry CHRISTmas to you and your's Paul

Matt said...

Love your stuff, Paul.

I'm not as optimistic that the future is going to be history free, but I like to learn about the new stuff. I think there will be more direct edit options in history modelers.

Shaan Hurley ( seems to make it sound like Inventor Fusion will enable both history and direct edit at the same time:

"It permits the parametric modeling (history based) modeling available with Autodesk Inventor to work with the direct editing (history free) of Inventor Fusion. You are not locked into one methodology of parametric or direct editing for a project and can use either based on the tasks at hand and combine the design data, the proverbial best of both worlds."

I agree with you that combining them is clumsy and awkward, but I think it's less awkward than abandoning history altogether.

Have a great holiday!

Joe Brouwer said...
This comment has been removed by a blog administrator.
Joe Brouwer said...

At this time large companies like Boeing are having a horrible time striving to integrate parts/assemblies from the many different CAD sources.

The problem is editing!!!

As you all know you just can’t edit non-native parts in a history base product. In fact many times you can not even effectively edit parts in the native product. We have all seen parts that unless you are an expert user could not be edited effectively, and the parts that were so poorly designed that the only solution was to recreate them, which of course causes huge chances for errors.

This is intolerable in an engineering department.

We now see he solution. Explicit Modeling.

Here are the products I sell, all are explicit modelers

I have sold Cadkey since 1986. I have watched the industry move from 2D, to 3D wireframe (where CADKEY started), surfacing and now, of course, solids. Cadkey, now KeyCreator is a hybrid modeling package, which means it can take any form of data and work with it in one 3D space, using levels to separate the data. It is also a very effective Explicit solid modeler.

IRONCAD is my favorite CAD tool, It is one of the only two packages that has successfully integrated both history and explicit modeling, the other being VX. The drag and drop capability, the integrated Boolean operations, the catalog with standard and custom features, parts and assembly makes it by far the best conceptual design tool. It also does very good explicit modeling since it implemented many of CoCreates capabilities. Yet is not to the level of SpaceClaim or KeyCreator in explicit modeling but has room to grow.

SpaceClaim. I laughed when this program came out. But now I realize that this came from people that were from the Pro/E, SW and other history based modeling world that started seeing its limitations.

Now KeyCreate, IRONCAD and SpaceClaim work in a UDE (Unified Design Environment). This means you can do your part, assembly and drawing in a single design space. One file can contain all the data to create that part, there by alleviating many of the PDM problems. This makes conceptual design very simple, since you do not need to separate the parts until you finalize the design. In IRONCAD the drawings are in a separate file.

IRONCAD has a model only package call INOVATE, that offers all the history/explicit modeling capabilities, but no drawing, sheetmetal or intellishapes (advance modeling functionality). It is a great add-on. It also includes integrated rendering, animation and kinematics with collision.

We need a standardized translator. Parasolid, ACIS and STEP are very good, but we need to get where the PMI (Part Manufacturing Information) and hopefully expanded to include associative drawings can be available. That is what made me interested in SpaceClaim, its incredible ability to read Catia 5 data including the PMI data. Boeing and most of their suppliers are my customers and are struggling to verify the latest data.

History based modeling it is very effective if you have a very stable design department and rarely use non-native data.

I believe 2009 will be the year of explicit modeling, with virtually all major CAD manufacturers now offering this capability.

And I wish all of you a Merry Christmas and a Happy New Year.

Joe Brouwer

P.S. I do enjoy both Jeff's and Paul's post and look forward to future input.

Mike R. said...


I just stumbled across your blog a week or two ago from Matt Lombards blog. I've been looking for a good source of information on CoCreate for the last 6 months or so after taking a job where that's the software in place. I can see where a direct edit option is useful after spending 8 years using more traditional parametric modelers. I do have my complaints about it. I really feel like the reason people started switching to 3D in droves is because of that part history/intelegence. I know you can add parametrics with cocreate but it's awkward at best. That history if done right allows somebody to take a model and know what you intended when you made it.

The other major issue I have is that no CAM system that I'm aware of can read a native cocreate model. You have to export and then import. What was one piece of data just because three to get what you want out of it.

I think that after using it for a while I fall into the catagory that does see a future for the technology but it'll be in a hybrid for like the ST in Solid Edge and NX.

Paul Hamilton said...

I really want to encourage people to pay close attention to the terminology used in the CAD world today. It is still very confusing and the CAD vendors are not making it any easier. Here are some absolutes:

A CAD system is either history based, i.e. tracks history (the parent child relationship) OR it does not track history, i.e. history-free, explicit, direct modeling (no parent child relationship). It can't be both. If it has history, it is not history-free. There is no combining the two.

A CAD system either has parametric capabilities (constraints) or it does not. It doesn't matter if it is history-based or history-free, parametric capabilities can exist in both. The capability either exists or it doesn't.

A CAD system either has direct geometry editing capabilities, or it doesn't. A history-free CAD system depends on direct editing, (it is useless without it). For a history-based system, direct editing is a nice to have feature.

So when someone says they are combining history-based with history-free, they are either completely confused or lying. It either tracks a parent/child relationship, or it doesn't. It can't be both.


You posted some comments from Mr. Hurley about Inventor Fusion:

“Inventor Fusion will enable both history and direct edit at the same time”. This would be nothing new as Inventor already has direct editing within its history-based environment. Maybe this is referring to enhancements with this capability.

Another quote: “It permits the parametric modeling (history based) modeling available with Autodesk Inventor to work with the direct editing (history free) of Inventor Fusion”. Does this really make sense to anybody? I hope not. What a confusion of terms. You are either tracking history or you are not. If you are not, you will not have it and there is no way to get it.

Another quote: “You are not locked into one methodology of parametric or direct editing for a project”. “Parametric” and “direct editing” are two completely different things and it is completely possible that they coexist. Constance of these two technologies is already available today in many of our CAD systems. In this case maybe the writer is using the term “Parametric” to describe history-based modeling, and the term “direct editing” for history-free modeling. If that is the case, the statement is completely untrue. You are in fact locked – there is no combining history-free and history-based. It’s a 1 or a 0.


I didn’t mention KeyCreator as we haven’t seen or heard much from these guys in 2008. Like CoCreate, they are one of the long-timer history free systems and certainly do contribute to this space.

IronCAD on the other hand is completely history-based. I don’t put it in the category of “history-free” or “explicit”. Their unique concepts behind the “Intellishape” does provide a much more flexible history-based environment than what is typical with other history-based tools. In IronCAD it is not difficult to feel the effects of the parent/child relationship behind the model. It is there, but it is concealed nicely. In IronCAD, edits are made directly on the intellishape rather than through a sketch or a set of parameters, giving it a different look and feel over other history-based systems. But don’t confuse it with history-free. The Intellishapes are ordered with a parent/child relationship.

I have another article started discussing the value of the history-tree (the parent/child relationship). When people talk about “combining” these technologies, I get the feeling that there is something that comes with a history-tree that people assume is still not possible to get when there is no history tree. And there is: the one thing that you cannot get in a history-free CAD system is a parent/child relationship (history). This type of relationship (parent/child) can be very valuable in some cases. With that said, what advantages/value can you get by properly utilizing a parent/child relationship that you cannot get in a history-free environment? There are several today, and I will attempt to explain them, and hopefully people will add others. But as the history-free technology continues to mature – the list is getting shorter.

Thanks for the comments so far.

Paul Hamilton said...


I agree that the integration of parametrics within CoCreate is a bit awkward. You can be sure that this will improve. As I mentioned, I think Siemens leads that pack right now with their integration of the technology. However they do not yet have the breadth of what CoCreate has in the area of history-free parametrics - as I am sure will also be improving with time.

One of the values you equate to history is that “somebody (can) take a model and know what you intended when you made it.” Why is this valuable? Does knowing the “model creation process” = knowing the "design intent”. Or are there other reasons this is valuable? I will agree that capturing design intent is still more convenient in a history-based environment than in a history-free environment – so far anyway. I’ll discuss this in more detail with a later blog. It would be good to hear more people’s opinions. Thank for the comments.


Paul Hamilton said...

Oops - Sorry, I meant to refer to Mike R’s comment in my last comment.

Mike R. said...

Eh Don't worry about it Paul. It's a slow day at work being the day before shut down so I don't have much to do but post comments on blogs. I know I come off sounding pretty negative about the history free approach but I do love the direct edit ability. I really think if you can direct edit with history you'd have a pretty great set up. Especially if you deal with a cast part then want to link it to a machined part like I do daily. We havn't been able to come up with a good reliably way to link them. That scares me. Maybe I'm a pessimist but I don't want to rely on people to make consistent changes to parts if the change occurs in the cast form. I want that change to trickle down from the casting to the machined part. As far as we can tell we can't do that in CoCreate if we could that would be a huge deal to us. The same could be said of being able to use native models with a CAM package.

Paul Hamilton said...


Yes - slow day for sure.

"cast part then want to link it to a machined part".

Right on - this is one of those high value capabilities that almost come by default through a parent/child relationship. I have yet to see something comparable with history-free. I've heard rumors that it is coming though (of course that is what they always say - "it's in the next release")

Joe Brouwer said...

Hi Paul,

IRONCAD can work totally explicit with a non-native or native part, it truly has robust direct faced editing capabilities. You can delete or edit blends or virtually any feature. You can make features from a non-native part smart, like blends, holes, etc.

If you are direct editing a face, like twisting it, it will destroying the history that is involved in that feature, leaving unaffected features history alone.

Intellishapes are basically an integrated function that adds draft or shell to a single feature like a block for example.

In fact you can combine all the features of the part to a dumb solid. It also has an interesting capability of Booleaning parts together and keeping the original inserted part free to be moved up and down the history tree or even replaced.

You should download it and play with it. It truly is the best of both worlds and truly does both.

I have been selling and using this package since the late 90's..


Anonymous said...

Paul, when I think about what is not desirable in history based systems, what comes to mind are the myriads of dependencies created between faces, planes, sketches, and constraints that are often created inconspicuously by the software on behalf of the user. Think about the fact that when a user creates a sketch on a face of a part, is he truly analyzing the part to insure that the associative link he is creating between the face and the sketch (and ultimately the feature) is going to fit into his future vision of the design intent of the part? Most likely it is not thought about until the feature that was dependent upon it fails later.

I believe that what direct modeling technology like Synchronous Technology will give us are models that have conscious dependencies built in to capture design intent, but will be much easier to edit because the several layers of the system generated dependencies are no longer there. Obviously this technology has to continue to evolve/mature to match all the capabilities of the current crop of history based modelers, but they have had 20 years to get where they are…


Paul Hamilton said...

Joe - Thanks for the extra detail. I will take a fresh look, and fix any mistakes I made.

Ken - Right on!

Joe Brouwer said...


If you want associativity across the spectrum from design to manufacturing, VX is the program for you.

I am a designer and basically send my parts to manufacturing. But if you are in control the compete process in a company VX is truly incredible.

VX history has basically a step by step functionality. Let's say you have an IGES file. You import it and VX will always, until it the tie is broken, look to that IGES file making it a live part of your design. You can do a complete design in one file by making it a session that includes all the components.

VX also has an incredible Mold design Module and CNC capabilities. You can import or design a plastic part and then design the mold, then do the CNC. If you change the original IGES or native part it will go through all the changes. Automatically updating the mold and the CNC tool paths, quite amazing.

A few draw backs is it is about 30% more complicated as a design tool as compare to my other products. Its translations are a bit incomplete. I have not downloaded the latest version, so it may have become a bit more user friendly. It is about 20% easier than Pro/E.

But it may be the tool for you. It has some amazing capabilities.


Anonymous said...

Without fully integrated CAM in products like CoCreate, Direct Modeling will fail to achieve significant market penetration in machining job shops.

The real power/secret of NX 6 is its fully integrated CAM.

Jon Banquer
San Diego, CA

Pascal Morenton said...


Thanks for blogging.

I want to add at your christmas list : PDM systems which can communicate easily with CAD tools based on STEP standards.

Direct editing tools have amazing capabilities to modify very easily any CAD data. Thus, we can create a amazing number of designs in one day or one hour ! But what about the management of these results ?

And if direct editing tools are dedicated to extended entreprise, what about the communication between SMB/SME CAD tools and the OEM's PDM system(s) ?

We are working on a easy and user-friendly connector between CAD tool (SPACECLAIM) and PDM/PLM system.


Pascal Morenton
Ecole Centrale Paris

Paul Hamilton said...


I will watch closely what you are working on with regards to the PDM space. There is certainly a lot of opportunity for improvement in this area. Most of the current PDM/PLM systems available today have turned our designers and engineers into data entry clerks. The best PDM system is one that we don't know we are using.


Kevin said...
This comment has been removed by the author.
Joe Brouwer said...


You don't know how sad we were when Boeing got rid of the Blue Print Girls and went to microfiche...

You are totally right.. The data management responsibilities should be in the hands of Document Control!!

We should have a universal neutral format. We need an ability to make an associated drawing available. Not to dimension every feature but to have a clear concise presentation of the design intent with GD&T, Manufacturing notes, and revisions.

As of now we have PMI (Part Manufacturing Information). This shows the critical dims in 3D and is a horror show, a totally inadequate presentation.

The reason I turned to SpaceClaim was its incredible ability to take Catia PMI data and actually transfer to associated drawings.

There is so much more to this... But I will stop here...