Dezignstuff SolidWorks Blog

When I’ve used direct edit software, there were some things I had trouble with. For folks with more experience these things might not be any problem. The main one that I wonder about is this, in its simplest form:

I want to go from this:

to this:

Where the bit inside the sloppy red circle is a straight section.

The way I assume you need to do this in direct edit is to break off the horizontal bar, move it, then add the rectangular section. In history-based software you just edit the sketch. Can someone shed some light on how this is best done in the  direct edit method?

I come from  a family of musicians and performers, so I’m the kind of person who cannot stand to listen to bad singing. Or people making fools of themselves on talk radio. I cringe in empathy, taking on myself the public shame that these people should feel. American Idol is out. I can’t watch most reality tv shows. Karaoke is nothing short of torture. And reading a bunch of non-history CAD developers tweet about “design intent” makes me fidget uncontrollably.

Some of these people are folks I respect, so I won’t do them the disservice of repeating what they think “design intent” is all about. It might turn out that I’ve got it all wrong, and everyone reading this is cringing for the public shame that I don’t feel. Who knows. I’m sorry if I make you cringe.

Who knows what design intent is?

First of all, if you were to look for an answer to what design intent is, who would you ask? A virtual reality addict? A general 2D/3D CAD programmer? A direct edit software salesman? An advertising salesman who used Pro/E 10 years ago? Prolly none of those, for the first round anyway. I’d ask people who are down in the trenches, making models that get changed a lot, a lot, a lot. People who take advatage of the “design intent” concept and people who get bitten by it. My guess is that the best way to learn to use it to your advantage is to get bitten a few times. I guess its ok for people who are not necessarily the “go to” people to talk about the topic, but then there’s a huge difference between singing in the shower, and singing on the capitol steps.

So what is it?

First of all is the longstanding public misuse of the word “design”. Design happens in your head. Design is developing the concept of how something looks or works. This is the kind of thing that cannot happen on a computer. It has to exist somewhere before it can be developed on the computer. The computer just records, organizes, or helps others visualize the design. The design was in your head before it was in the computer. If such a thing as “design intent” exists, it consists of a reason for geometric elements or selection of material or manufacturing process. The reasons would be the intent. And the design is the design.

When CAD people use the word “design”, they usually mean “model”. Modeling, to me, is just representing the design in some way, either a set of equations or geometry shown on a computer screen. If the design is the concept, then the model is the digital prototype. Ok, whatever, you get it.

Design for Change

In my books, I have had to address the  concept of “Design Intent” because over the years, it has worked itself into the mindset of all CAD developers, and you can’t take a basic SolidWorks training class without hearing it. It’s kind of like the non-word “refudiate”, which kind of sounds like it should be a word, but its not, its just an accidental mashup of “refute” and “repudiate”, which mean roughly the same thing. Still, I don’t think most beginners have much of an idea of what design intent means in a practical sense.

Ok, so maybe the free association wordplay here is a bit of a stretch. Design Intent = non-word = refudiate = Sarah Palin. Design for Change. Change = Obama. The silliness of it all is quite a dance. Yeah, if you’re wondering, no, I don’t take any of this too seriously.

In the books, I side step design intent, and equate it to the phrase Design for Change. This implies that you are modeling a concept that can be flexible through changes. To me this is more straight forward, being simpler to explain and understand.

The direct edit caucus seems to want to ridicule “design intent”. We call their models “dumb”, so they resent that we think our models are smarter than theirs, especially when part of making changes to the intelligent model requires so much fixing of broken features. The truth is that most direct edit software allows you to apply dimensions and relationships to the faces of the finished model (brep), so you don’t have history, but you still have intelligence. That’s a nice advantage, to be able to forget history, but still use parametrics. I like that about direct edit.

But I don’t always like that. Sometimes the order in which features are executed is its own kind of intelligence. Like fillets. The weaknesses of history modeling are rebuild times and sometimes untangling relationships between features. The weakness of direct edit is that you have to resort to barbaric measures if you make changes beyond the capabilities of the brep, and the fact that you have to deal with the whole model as a single entity – you don’t always have the ability to break it into features. The argument is not about parametrics, its about history.

In non-history modeling, you can still have “design intent” or design for change – but in part you are limited by the ability of the brep to make changes. What I mean by that is shown above. I want to move the boss on the left, but when I move it, the fillets between the boss and the rib will not allow me to move it past the point where the boss is tangent to the rib. Individual softwares may have ways of dealing with this, but if you’re dealing with the brep as a solid, you can’t separate the boss from the rib, and the rib can’t fail because its not a feature. You would either have to move the rib with the boss, or delete the faces of the rib and the fillets. So there are certain types of changes that get really ugly in direct edit, equally as frustrating as anything in history modeling.

So, what does “design intent” mean to you? If you’ve used direct edit software, what do you see as the “design intent” advantages and disadvantages?

You might remember some time ago that Solid Edge made a huge splash with what it called Synchronous Technology. At the time, I got to use the software, and even got a day of training on it. There were things about it that were very impressive, and things that weren’t so impressive. Synchronous Technology, or ST for short, is essentially direct editing – the ability to move faces of the model directly without the need to edit features. The main selling point of the technique is that it is “historyless” – playing off of parametric software users fears surrounding dealing with a history-based feature list in a complex model. SolidWorks has some tools that work in a direct editing sort of way, but nothing that really compares to the functionality found in ST.

I’ve written a fair amount on the pros and cons of ST. Follow the link and browse the entries from the bottom up. To summarize it, I think ST is great, but I would not give up history to get it. My best case scenario would be to combine the strengths of history and direct edit techniques, along with some history tree management ideas. I think some of this is going to show up in SolidWorks sooner rather than later, and it may even be showing up in Solid Edge in their soon to be released ST3.

The hype around the initial release of ST was enormous, especially the hype created by the media (people who get paid to talk about software but don’t really use it), but it was unclear if anyone actually took a critical look at it to see if there were any limitations. When actual users were let loose on the software, limitations became apparent. To me the most serious drawback was that once a face of the b-rep model was consumed, getting it back is far more difficult in direct edit than in history. Another way of saying that is that if the design intent changes, in some cases you are left with some pretty primitive methods to achieve what you are looking to do. I came away with the impression that you had to have very good understanding of b-rep modeling in order to understand what kinds of edits would work, and which ones you would have difficulty with. The hype around ST soon faded, and disillusionment set in for Solid Edge customers. ST was being hyped at that point in the same way that Cloud is being hyped now by a different CAD company. While ST did definitely have some advantages over history based modeling, in my opinion it was far from something you could just rely on 100% for everyday modeling tasks.

Claims that ST or more generally direct edit was the “future of CAD” were a little bit of the boy who cried wolf. You hear that future claim every time someone resurrects a failed technology from some previous decade. Direct edit and Cloud both fall into that category. Not to say that both technologies won’t play some role in the future of CAD, just that I don’t believe either one will exceed say 20% usage.

After having done some reading around the web, it seems to me that the ST was integrated better into NX than it was into SE. In SE you are pretty much limited to prismatic shapes, but not so for NX. While I do foam at the mouth a bit when I think of having a full license of NX, an office of my size can’t really afford that kind of thing. This is why you don’t see a lot of user run blogs based on NX – it is primarily found in larger companies that deal with much bigger ticket products where that huge price just disappears into the overall project cost.

Changes worth noting

The big news these days is the renewed energy Siemens is putting into Solid Edge again. They have a new fellow in charge (Karsten Newbury), and many of the old guard are gone. Also gone is the claim that ST is going to fully replace history modeling in a couple of years, even ST apologists are saying that history is still the only way to do some things. I’m hearing (from people I want to believe) that Siemens is paying attention to what users are saying, and that Synchronous Technology 3 is going to be all that the original release could have been. I think it was a mistake to put up such a rigid wall between ST and history. Direct editing on its own has limitations which have made it a second-place technology in a two horse race. I’m not sure a new coat of paint and a well written press release is going to change that. I think the answer to a really great product is not a revolutionary change that turns the world on its ear, but rather an evolutionary change that looks at two seemingly polar opposites and sees in them some compatibility. You can’t ask power users to give up the undeniable power of history, and you can’t relegate Solid Edge to be used only by the Spaceclaim target audience (downstream 3D data consumers). Someone has to take the step and combine the two.

How? I think I laid some of that out in this post a while back. It would have to do with history tree management – mitigating some of the shortcomings of SolidWorks implementation of history-based modeling.

Anyway, this post is more about Solid Edge than SolidWorks.

Siemens may actually be putting some resources behind trying to get users interested in the Solid Edge Product. Along with the ST3 release, Siemens is conducting a “Solid Edge Productivity Summit Tour”. As I understand it, Solid Edge does not have the base of user groups that SolidWorks has, but this tour might be thought of as the equivalent of a new version rollout training session.

Anyway, if you have any interest at all in this, check out the Solid Edge Synchronous Technology blog. The ability to use ST in “smaller chunks” may mean that they are starting to meld ST with history. I really believe this is the best way forward for both technologies. If you are tired of hearing about your CAD vendor with its head in the clouds, you may find some relief in hearing from a different vendor who is at least trying to solve CAD problems rather than licensing problems. If one of these events is in your area, check out the website and tell them you’re coming. Attendance is complimentary, and they provide lunch.  The event agenda is here.

Then come back here and tell us how it was.

Now that the furor over direct edit has passed most users by unaffected, and it looks like SolidWorks is the only company that doesn’t have their hair on fire over this topic, maybe its time to reexamine it, especially in the context of history-based modeling. There is a lot of background reading that you can do here on this blog, by going to the Categories drop down on the bar to the right and selecting Direct Edit, or by going to Phil Hamilton’s blog, also with a link in the side bar.

I’d really like you to go back and read this one post on how SolidWorks could make their implementation of history-based modeling better. If you need something more basic, here is another primer post. The more I think about it, this blog post really contains what I think is the key to SolidWorks moving forward and laying to rest some of the silly accusations of the direct edit marketers. Who knows, it may even hold some keys to what Autodesk is messing with in Fusion. The ideas are from both me and people who have made comments on this blog.

Anyway, I want to take a more practical look at how some direct edit functionality currently works in SolidWorks, and some philosophical questions about if you are going to create the CAD equivalent of a black hole or a loop in time by using direct edit and history based modeling at the same time.

Phil Sluder is one of the better SolidWorks users you will find anywhere, and I’ve heard him express this sentiment before. He’s not the only one. I’ve said something like it from time to time. Phil’s tweet reminded me of this (and coincidentally gave me an opportunity to show what I think is a useful use of Twitter for work purposes, even though he didn’t fit his idea into only 140 characters).

Just look at what Phil has to say. He just moved some faces instead of changing dozens of dimensions. Is he being sarcastic? Is cutting down your work like that really that “sleasy”?

I totally agree with Phil. I think you can only understand what appears to be a sarcastic contradiction if you’ve actually gone slease yourself. Admitting it in public is the next step. I’ve done it a number of times myself, but the only part of it I’m proud of is how much time I saved by understanding advanced functionality. I don’t get a feeling of heroism for following the rules regardless of the cost.

Phil said the part deserved it. What could he possibly mean by that?

Well, here’s an example of a part where I used some sleasy modeling methods, and I saved myself a ton of time, and yes, I think this part also deserved it.

This is a part I’ve shown a few times because it has a lot of great examples of different kinds of modeling in it. First, it is part of a set with another very organic looking part, and they have to fit together perfectly on some organic shaped surfaces. That’s nasty. It’s really part of a family of parts that I’ve been working on for the last several years, including size and functionality differences. Originally there were some master model type techniques going on, but with all of the impossible changes and with the range of sizes, much of that is just a distant memory. In all, these parts have features that are long forgotten, some that were made and never used or removed, some that were created, then cut out but not deleted, and so on. In all, it’s like a concept model that never got cleaned up. And yes, hard tooling has been made from some junky data. With all of the changes the customer makes, from time to time, I have had to just go back and do a fresh remodel on a part rather than have another hack at it.

The point here is not the fact that from a parochial parametric point of view the data is ugly junk. The point you need to remember is that you don’t need to be so parochial about your data. You can actually work with “ugly junk”. In fact, there are several software tools that use this ugly junk method of modeling exclusively. In this case, I’m thinking particularly of something like CoCreate. The modeling I am calling “slease” and “ugly junk”, are what other people call direct editing.

Anyway, back to the part.

In this part, I just used the Move Face tool to offset the outer faces that were created by a set of features including sweep, split line, boundary, loft, trim, delete face and replace face. I could have gone back in history and changed a couple of sketch dimensions in a couple of different sketches, controlling different features, and take the chance that all those down stream features are gonna blow up, or I could just put the Move Face at the end of the feature tree. Oh, and there is a Scale feature in there somewhere too, so I would have to back calculate the sizes needed so the scale would come out correctly. Is your head ready to split yet? Do you blame me for going “sleasy” on this one? It probably saved 45 minutes, or possibly a couple of hours if I had to repair a bunch of features.

On the downside, next time I edit this part, I’ve got to remember what is driving the final shape. I’ve got to remember that the Move Face feature has final say, and not the Scale, or the sweep, or the loft, Move Face has some characteristics that make it a wonderful tool, but the same characteristics can be maddening. For example, if you use Move Face on a model, it does not rename the face or edges (unless it causes a face to intersect with faces different from the original intersected faces). So that means that if you click on a face moved by Move Face, it lights up the original feature, not the Move Face feature (unlike some features such as Split Line).

Here’s another one in the same part:

If anything, this one is even uglier than the first one. The image shows the result of an offset. The alternative to this was to edit a shape in another part that was inserted into this part, which would probably involve adding a configuration so that the one version would be used here, and the other version in the original context of the part. In short, the lip around the part shown here had to be treated like imported geometry. In the original part, the faces were created by a complex lofted surface cut, then the faces were brought into this part and made into a solid. So I could go back and try to mess with all of that, or I could just do what is completely natural in CoCreate, and just cheat, and use the Move Face tool.

I’m not sure what type of parts Phil was working on, but I recognize his conundrum. History-based modeling is all about process. Most of us recognize a lot of benefits from that history-based process, but it can sometimes be difficult to manipulate. Sometimes it is easier to just step outside of the process.

I’ve had a look at Spaceclaim, and CoCreate and Synchronous Technology, and I’ve got to say, that there are things I like about being able to ditch the process. The big argument is that the history is A) hard to undersand and B) bogs you down with rebuild times. These are true to some extent, but the marketers are trying to instill fear, while going short on facts. The history-based implementation in SolidWorks is not so hard to understand because you can click on a face in the model, and it scrolls the selected feature in the FeatureManager (requires a setting – Tools>Options>FeatureManager>Scroll Selected Item Into View). The demos for direct edit modelers represent people fumbling around with a tree trying to find which feature controls which geometry.

The rebuild times claims are true, but for the types of geometry that you can actually edit with something like Spaceclaim, the shapes have to be simple, so the trees are likely to be less complex than more complex geometry, and in that kind of part the rebuild times are not much of a problem. The direct edit marketers found a valid pain point in history based modeling, but I think have failed to demonstrate a relevant connection between their solution and our problem.

In the end, SolidWorks can currently handle both history and direct edit functionality simultaneously, but seeing a direct edit feature in a history based tree begs some underlying questions. I only use these methods when I have to, or when its not an option to do it the correct way. Even things like patterning or mirroring faces can be considered direct edit. These are considered valid ways of working in the direct edit world. I really think that if SolidWorks takes the ideas in the history implementation post and combine them with improved direct edit tools and functionality, they will have an unbeatable combination that will settle the history vs direct argument for the foreseeable future. The existing tools are good, but raise a lot of best practice questions. Additional control over rebuilds and the tree are needed to make this really make sense.

In one of Dan Staples recent comments, he reacts against the term “dumb brep”. First, I need to explain brep. B-rep is “boundary representation”, which means basically the set of faces it takes to make a model. The faces exist in their “untrimmed” form so that some or all of them may be oversized. The boundary faces are a combination of the raw face data and the trim boundary edge.  So you can think of the b-rep as the collection of sheets of fiberglass used to make a fiberglass boat. The finished model looks just like a boat, but the b-rep includes faces that are larger than the finished piece. I’m sure that’s not a very good description, maybe Dan can give a more technical or more effective description.

In SolidWorks, working with the brep enables you to almost extract history from an imported model. Remember that the finished brep consists of A) the COMPLETE underlying faces (four sided with no interior holes) and B) the trim boundary (trim includes any holes and any perimeter shape that keeps it from being four sided). In SolidWorks, you can use the Untrim and Delete Hole features to get rid of the trim boundary, and just give you the underlying brep face for any imported model face.

One of the useful ideas behind a b-rep is that you can move individual faces of the boundary, and if the faces around it are large enough or are analytical so they can be extended indefinitely, the model will maintain its integrity. This is what Dan is saying when he says that the brep is incredibly smart. He’s right it is! For faces to extend themselves and trim themselves is great. He seems to say that the brep also understands tangent, concentric, etc. I thought those were functions of the modeler, not the brep, but Dan knows that area far better than I do.

Anyway, the boundary representation is created by the geometry engine in a CAD program. CAD programs generally don’t create their own geometry directly, they have a separate software component do that, which is sometimes licensed from another company. Software like SolidWorks is really just an interface around a modeling engine (or kernel). Solid Edge (ST and traditional) and SolidWorks are both driven by the same geometry engine – the kernel – Parasolid. You can transfer a brep made in Parasolid to an Acis or a Granite kernel, and all these kernels communicate through NURBS geometry definition. That was one thing the industry agreed on. Alternatives to NURBS are point cloud (mesh – 3ds max kind of stuff) or as I understand it, this new T-splines business. NURBS is used for manufacturing because of its high accuracy for complex shapes. Mesh/point cloud is used for computer graphics because of speed and close relation to display data.

In parametric history based modeling, we (meaning “I” or maybe SolidWorks users in general) usually think of the brep as being dumb. The closest thing to a brep that we actually see is imported geometry. To SW users, imported geometry seems dumb because it doesn’t have “intelligent” features that you can edit. But to direct editing people, there is no such thing as dumb geometry (not completely true, but we’ll just go with that for now), because the direct editing software allows you to just directly access the brep, and move the face boundaries. In SolidWorks we edit the brep indirectly through sketches and feature definitions.

So in essence, both direct and history modelers are doing the same thing – editing the brep – but they do it directly and we do it through features and sketches. If we lose our features and sketches we don’t have anything to go on, but that doesn’t matter to the direct edit people. Part of the beauty of direct modeling is that the intelligence is in the interface, not in the model (although remember, the brep has some type of intelligence built in because of the separation of the brep faces and boundary edges). With history based modeling, our intelligence is in the model. I personally think it is easier to put intelligence into the model than into the interface, but you can’t always tote that model intelligence with you, because the CAD companies are too busy trying to hoard customers to enable real interoperability. If the CAD companies were a little more concerned with the state of the technology than their petty bickering, we could have models that would transfer intelligence from SolidWorks to Solid Edge and vice versa. But we don’t have that so the next best thing is direct modeling.

Anyway, with some of this new stuff, like ST, they do add some data to the file to make it changeable, so their model is not just straight brep data. They can externally create relationships and dimensions between faces (parametrics), so all of the intelligence isn’t in the interface, and the ST native file is more intelligent than the straight Parasolid brep. They also have procedural features, which for me are a little hard to get my head around when trying to think of it all in context. I think all of this is a tip of  the hat by the direct editing crowd to the power of history based modeling. They probably look at it differently, but I think they recognize that direct edit on its own is kind of raw – you do need some model intelligence to do some things. For example, changing a through hole to a blind hole in a direct modeler would not be straight forward. If the hole has some sort of a feature based definition that functions like a geometry creation wizard to do things like that for you.

History based modelers have already embraced direct edit type functionality to some extent, and I think should do more of that. I still think the future of CAD is between the two somewhere, not at either extreme. Right now, the way direct edit is implemented in products like SolidWorks kind of makes a mess of a history based model. Frankly, I don’t know how exactly to combine the different ways of working other than the way it is right now, but this next software might have an idea about that…

I’m the only one talking about solidThinking in this respect, at least that I know of. I wish some others who know the software would join in the discussion. I said earlier that to direct edit, there is no such thing as dumb geometry, and that it wasn’t completely true. When you have complex (non-analytical) shapes, some direct editors still cannot deal with that very well or at all, so those editors see the complex shape in the same way that SolidWorks sees imported geometry. Some are limited to basically flat, cylindrical, conical, toroidal, spherical, and ruled type faces. solidThinking is a history modeler with a lot of complex shape direct edit capability. Can we get Alessandro Mazzardo in here to comment and educate us a little? Somehow they manage to maintain direct edits to complex surfaces that were originally built using history based method. The direct edit data is not added as a history based feature in the tree (at least I don’t think it is). 

Anyway, a lot to think about here.

On Shaan Hurley’s Between The Lines AutoCAD blog you can read about Inventor Fusion, shown at Autodesk University. Am I going to review this one too? Probably not unless it gets some positive reviews from elsewhere. You can go directly to the Inventor Fusion website to read about it and watch some videos. Some of it looks good, and some (even in the demos) looks really bad. There are things that look to be directly lifted from both Solid Edge and Spaceclaim.

The Fading Buzz

Well, the buzz has died down. The party has passed. Now we will see if Synchronous Technology is really going to turn the history-based CAD world on its ear. The pundits are nearly unanimous in saying that it is indeed revolutionary, and that it is going to make huge changes in the directions of all the current history-based CAD products in the not so distant future. But do people who will wind up using the software agree?

Disclosure

I have to make a couple of things clear before I go on. Siemens paid for a trip to Huntsville, Alabama with an overnight there. I spent the night before my meeting with them at Ricky Jordan’s SW user group. At the Siemens offices I met with several executives, technical and marketing types, and others. They gave me a demo and then some hands on training. I got to ask all the questions I wanted to ask. They have given me a copy of the software to use while exploring the possibility of doing some writing projects. In the end, the only writing that has come of it has been whatever you have read here at this blog and a two-part article for Desktop Engineering written months ago, which has yet to be published. 

The folks at Siemens are bright, and they believe in what they are doing. They were excited to get an opportunity to put the software in front of people who both write blogs and use software. I believe they also approached other SolidWorks-using bloggers (or blogging SolidWorks users?) but I was the only one who accepted. I’m an independent and can be more flexible with my time than other folks who work for the man. They were courteous and curious, but kept me at arms length. They knew of my love-hate relationship with SolidWorks, and weren’t looking to fan the flames. At the same time they didn’t want to have any ire directed at them. I think they invited me because I was the one SolidWorks blogger who showed the most interest in Synchronous Technology, and I was at least trying to understand it.

Target Audience

Solid Edge with Synchronous Technology is aimed at people who think that history-based modeling is too difficult or time consuming. They want to create a market for CAD non-specialists. The Solid Edge people clearly believe that this brand of  direct modeling is going to not just be competitive with history-based systems, but completely replace it. SEwST is somewhat different because it includes regular Solid Edge, along with SE’s assembly and drawing tools, and sells for the same price as SolidWorks. On the other hand, what’s new about SEwST is most similar to Spaceclaim, and in ways also related to Sketchup Pro, Key Creator, CoCreate and Iron CAD. While details of it are arguably new, I don’t believe you can make a serious case for SEwST being “revolutionary”. The functionality that goes to make it up is already found in other places. I’m not an expert in these other softwares, and I haven’t used them (aside from a short stint on CoCreate many years ago), but I have tried to keep up with the writings of people who have used them.

Available Sources

In addition to actually using the software, I have gone to a couple of sources to read about Synchronous Technology. There is of course the Solid DNA website, which takes the fanboy approach, which I take to mean claiming its just better without giving real concrete reasons. I have a hard time with this approach. There is of course the Synchronous Technology website, which I take to be a corporate blog because of its lack of objectivity. Probably the person who makes the best case for the concept of Synch Tech is Paul Hamilton, even though he is associated with CoCreate. I’ve even read a little Al Dean, Roopinder Tara and Evan Yares. Paul is an obvious cheer leader because he is employed by the industry, but what he writes is valuable if you are trying to understand what’s going on, even if he is writing primarily in favor of a different product. You have to filter out the unbridled optimism from what he says. The other press/pundit types are very enthusiastic, and while they have each actually used the software, I think it has been a long time since any of them directly used CAD to make a living. Their enthusiasm seems unexplainable to me. At least that’s the way I’ll leave it.

Eng-tips is another place you might go to read about user reactions to Synch Tech. I’ve been booted out of eng-tips a few times now, usually for doing what someone considered “advertising”, which turned out to be just stumping non-commercial sources of information. Really odd thing to do for a site that is plastered with advertising and is right up in your face with their sign in. Eng-tips has always seemed to me to be a place that enforces a smiley face, where everyone takes a hit of prozac before posting. This commentary is relevant because of the unusually negative tone eng-tips users display when talking about Synch Tech. Anyway, most of what you read on eng-tips is not favorable to Synch Tech, and it is all from the end user point of view. They seem primarily confused, then betrayed, even bewildered. Sometimes the information they give out is incorrect.

Evolution of Views

Early on, when I started writing about Synch Tech, I was just trying to spark a conversation about it. I obviously hadn’t used it. The other people who said I was wrong about things also hadn’t used it. They were right that I was wrong, but I think they were also wrong about what it was. At one point I called the combination of history and non-history based tools “FrankenCAD”. It turns out that was incorrect too. Frankenstein’s monster was a single being made from multiple beings. SEwST is really two separate beings. More like “Dr.-Jekyll-and-Mr.-Hyde-CAD”. You work in one or the other. You can’t go back and forth, and the features of one are not maintained in the other.

Synch Tech and Traditional SE produce different types of parts. You cannot read ST parts in SE, but you can read SE parts in ST. So this is a one-directional translation. If you talk to resellers, ST is the future. Siemens hopes to eventually migrate all SE users into Synch Tech. This means they are forcing users into a completely different workflow. The interface is partially the same, but the workflow and the bulk of the tools will be a learning experience for SE users that get forced to ST. Some of the sketching concepts remain the same, but with ST, sketching is for creation only, not for editing.

I should mention that Synchronous Technology is also a component of NX (formerly Unigraphics). And if you’re one to look out into a crystal ball, Catia V6 is said to be based on a kernel that may contain elements of what Synch Tech does.

Siemens has had a lot of difficulty explaining exactly what ST is. Maybe it was their goal to create a lot of confusion, because it added to the mystery, buzz and hype.

Synchronous Technology Is…

In the end, Synchronous Technology is:

• direct editing
• history-free
• parametrics applied directly to the faces of a solid model
• treats imported models almost the same as natively built models

It is also more than that, but that does for an introduction. Some very clever functionality that recognizes face relationships and applies geometric relations on the fly helps you add relationships to the model as you make changes.

My Experience

What I found by using the software was that there is a reason why most of the demos you see for ST involve editing geometry. That’s because editing is the one area where it has some real strengths. If you need to edit an imported model, a direct editing tool is the only way to go. 

Actually building things in ST can be a little frustrating, particularly if you are used to a different way of doing things that involves using construction geometry. This seemed to be an obvious lack, especially when it came to setting up symmetry in a part. I found the software to be just lacking in tools. If this is intended to be a tool for non-specialists, it has a long way to go. The couple of extremely basic tutorials that exist for ST were not adequate to answer the many questions people have about how the software works.

Relying on the Live Rules to automatically apply the geometric constraints with each edit means that you have to check that it got the right relationships each time you edit. In the end, I didn’t feel I could rely on this to automatically do the right thing.

The workflow didn’t work for me either. Selections were order dependent, which might be a Solid Edge thing rather than exclusively Synch Tech. Also there was none of the click-drag interaction, it was all click-click. Something SolidWorks users at least will recognize. Many settings or options would not preview, so you had to accept the setting before you saw the effect. Just didn’t raise my confidence. Maybe it seemed un-intuitive because I’m ingrained in another way of doing things. The direction of change was the wrong way for “ease of use”. SolidWorks is far more flexible when it comes to pre- or post-select, click-click or click-drag, and definitely better with previews.

Of course there is the major limitation of working exclusively with extruded or revolved shapes. This alone will be a deal killer for many users. Fillets in any system are dependent upon the order in which they are applied. The problem in ST is that you can’t change the order. The only good news here is that undo and deleting faces work very fast. Still, you might be surprised by the kinds of changes you can make around fillets. ST can definitely make changes where fillets are involved that would completely choke SW. 

Even so, sometimes fillets would limit the types of changes that could happen. If you combine the ideas of entropy and model topology, changes in the model can only lead to simpler topology (fewer model faces). If you make a change that removes a face from a model, there is nothing you can do (aside from remodeling the feature) to get the face back. That is to say that once a face is removed from the b-rep, it is gone forever. In Solidworks, because the b-rep is built in stages, as long as a face is built by a feature at some point in history, you can get it back if another feature cuts it away or covers it over.

Siemens has gone to great lengths to establish the limitations of history-based systems. But I think there are a few things they didn’t count on. First, the types of parts that ST is limited to (prismatic face shapes) are not typically complex parts. I also think they have dramatically overstated rebuild times for the types of parts ST can edit. It’s true that complex parts have rebuild times in SolidWorks that are unacceptable, but ST cannot edit complex shape parts. I think their argument in this direction is misleading. If you can show me a part made from extrudes and revolves where it is built efficiently and has more than 400 features, I may retract that.

Further, I did a large pattern in ST one time, and it is time consuming to create and edit it. Patterns and other types of features such as holes and fillets are considered “procedural” features, which means that a feature definition is stored for those types of features. Large patterns take a lot of time in ST as well, maybe significantly less than SW, but still a lot of time.

On the up side

There are some things I wish SW could learn from SE and particularly ST. I know I’m always grousing about this CAD stealing ideas from that CAD, but I just want to point out that it is not all bad news for SEwST. First is the ability to select one side of a dimension and have the dimension change in that direction. In underdefined SW sketches, it’s a complete crap shoot as to which side of a sketch will change.

I loved the ability in ST to completely ignore rebuild times (because they didn’t exist). 

Surprisingly shelling has some advantages with this system. You can selectively shell a shape more easily with ST than SW. By selecting the faces to “thin wall”, you can exclude an area from being shelled. In SW the workarounds for this are feature order or multibody modeling. Neither is as good a solution as selecting faces to thin wall. On the down side for ST is that if the number of faces is large or the topology is complex (split into many small sliver faces), selection can be nightmarish.

After using SEwST, I have a new appreciation for the Instant3D tool in SolidWorks. I still don’t think I will use it, but for people who are simply too lazy or really in that much of a hurry, it offers a way to edit the underlying history-based model without regard for the history itself. It doesn’t work all of the time for everything, and it will never find its way onto a best-practice list, but it is an interesting and useful tool. Also, the SolidWorks Move Face tool is a pale reflection of the “steering wheel” functionality in ST. 

One huge topic SolidWorks could benefit from having a look at is feature tree management, rebuild management, and a few other things in that direction. Check out this blog post where I suggest a few things SW could do to improve overall rebuild speed by getting rebuilds and the tree under control.

Summary

The concept of direct editing as embodied in SEwST is beautiful. It solves problems from interoperability between different brands of software to version compatibility within a brand. Those alone are super compelling ideas for me. For editing imported models, this system is in its glory. How often you do that determines how much you need this. 

For comparison, Spaceclaim (another direct modeling system) sells for as little as $775 at Novedge. SEwST has much more functionality, and sells for starting at ~$4k. If all you really need to do is edit imported data, you might consider something a bit less expensive. 

For a system aimed at non-specialist users, SEwST is far too complex and process dependent. You can’t just pick it up and understand intuitively how to make changes or how to apply the parametrics. It will fail to edit sometimes, and if you are not a b-rep analysing type of user, you will never know why.

Solid Edge with Synchronous Technology is a nice alpha version of the software they are should one day create. I think the interface needs to be less busy, and less cryptic. It’s even worse than SolidWorks when it comes to replacing text with icons. It is great technology, and a fun tool to use, but with all of the limitations it is not a SolidWorks killer, and in its present state Solid Edge users will not be happy to be forced to ST.

Before you read this article, go over to Jeff’s Blog and read his post on Reverse Compatibility. I’ll wait here patiently until you finish. It’s short and uses small words so it shouldn’t take too long.

Ok. I’m posting my comment here, because, along with “never eat anything bigger than your head”, my mother always taught me that the “response should never be longer than the question”. I don’t have that gift of brevity and simplicity that Jeff has, so I can get as long winded as I need to get here on my own blog.

Jeff claims to have a reliable source for this reverse compatibility claim. I think the anonymous source is leaking a severe understatement. I think this will turn out to be the first wave in ever more tantalizing leaks about groud breaking stuff that SW is planning. Let me tell you this: They are toying with you. Once you know what is really happening, you will look back and see this leak as disingenuous rather than simply interesting.

Let me guess what the next leak is going to be… can’t play the performance card again, users are still crying wolf over the 2009 supposed performance increases. Maybe it will be something to do with making your FeatureManager more manageable. Or maybe the ability to treat any imported geometry as native. Or maybe rebuild speed for parts. Or maybe external references without external references. Or maybe more controllable sketch relations. Or maybe better control over feature order. Or maybe you could just take one of my recent posts on history-modeling and pick a topic from one of those.

Do I have some sort of inside information? No. I’ve been officially excommunicated because a SW VP came on my blog and shat all over himself, and they had to have someone to hang. Eric Droukas, a former SolidWorks employee proclaimed on Twitter

What happened to SolidWorks? http://dezignstuff.com/blog… Unfortunately, this is an example of how not to communicate with users 4:59 PM Aug 21st from web

So the 45 people who commented, the nearly 300 people who voted and me aren’t the only ones who think the VP was way out of line. But I’m the one who got hung for it. Looks like we are dealing with frail egos. Previous and more secure SolidWorks administrations dealt with criticism in a much more productive manner that was beneficial for both sides. Excommunication doesn’t really affect me much, but I can tell you it doesn’t improve my opinion of SW leadership at all. The new regime in Concord has driven out some good talent, and they don’t have the charisma or engineering interest of either Hirschtick or McEleney.

Anyway, just pointing out that I don’t have any inside information. I can read, though, which is sometimes better than inside information. Remember I posted (and then JB the CAD Terrorist copied it on comp.cad.solidworks) that a Wikipedia entry on Catia V6 points out that the V6 kernel is based on direct editing? In an article soon to be published by Desktop Engineering, one of my points is that the whole version compatibility issue is one that is if anything actually underhyped by the Synchronous Technology marketing blitz.

The term “reverse compatibility” is one that was delicately crafted by history-based modeling people, and is intended to make the idea of compatibility between versions seem absurd. Compatibility is compatibility. “Reverse” compatibility is nonsense. It would be better to just call it “non-compatibility”.

SolidWorks has spent a lot of effort trying to convince people that because of the annual file structure changes and new features added to the software, version compatibility in SolidWorks is impossible. This is BS. With all of the tricks they employ to read file formats from other major CAD players, they can certainly do something in the version compatibility area if they wanted to. This is a breakdown of the will, not of possibility. The marketing ratchet keeps people pushing forward.

For an eye opener, if you have some time to kill, read a transcript of the Dassault Systemmes conference calls. More than 60% of DS revenue is from subscription. They are going to drive that treadmill as fast as they can through a sheer profit driven application of technology. Here is a quote from one of the transcripts. Grabowski pointed this one out to me in this article.

Driving these results were strong growth in subscription revenue, which was up about 20% in constant currencies. Unit growth was more subdued at 2% on lower and new license activities in Americas …

Anyway. How does version compatibility relate to this? Well, I think DSSW sees a light at the end of the tunnel, and it is indeed another train. Right now Synchronous Technology is getting beat up by users. If you go to the eng-tips Solid Edge forum, you see that there is a good deal of skepticism about ST. Some people have drunk the kool-aid, but users aren’t really buying it. I think it will take some time to get widespread acceptance partially because users have a lot invested in learning history-modeling, and partially because the ST and similar are still what I consider to be in pretty primitive states. SolidWorks 95 did not knock Pro/E out of the ring, but 2001 and later did. Direct editing is going to have to mature a lot to knock history-modeling out of the ring, but the potential is there. 

So, SolidWorks is considering version compatibility, which it has previously scoffed at as impossible? No doubt. It is because they are going to be forced to compete in a new direction – direct editing. Catia V6 kernel makes this possible. Synchronous Technology and Spaceclaim make this necessary.

If you’re the kind of person who needs to have things perfectly nailed down and defined, you might possibly be better served by some other blog. I sometimes get involved in conjecture, which means that I’m looking for facts rather than presenting facts. It seems there are a few people out there who do not understand the difference, or don’t accept that conjecture is a valid pursuit.

Anyway, you’ve been warned.

We’re closing in on it. We’ve talked about several topics surrounding the Direct Editing craze that is making its way through the blogger, press and analyst circuit. Users are not silent on the issue, but what they have to say so far sounds relatively uninformed. More on that later. For now, on with the show.

From a previous post, history modeling brings advantages as well as disadvantages. There is both downside and upside when you separate history from the rest of the attributes that we normally associate with history modeling. I think we tolerate history modeling primarily because we don’t know anything else. It isn’t clear to me that history modeling is necessarily the best way of looking at all types CAD models. This is all I’ll have to say about history modeling for this post.

Parametrics, on the other hand, I think has clearly demonstrable advantages. The ability to make geometric relations, using equations, dimensions, etc. This is the kind of thing we use to establish “design intent” or an “intelligent model”.

What interests me today is if you can separate parametrics from history, and if you can, what would the result look like? What is parametrics? It’s just the use of “parameters”, right? We have come to think of “parameters” as dimensions, numbers (for patterns), equations, relationships, stuff like that. So what if you took that stuff and just attached it to the finished model? Is there any reason why you can’t attach dimensions and relations to the finished model instead of to sketches and in dialog boxes?

If you look at SolidWorks, you can put dimensions on the finished model, but they are driven dimensions, reference dimensions, they just measure, they don’t drive. I understand the interface for doing this doesn’t exist within SolidWorks, but let’s just say that you’re God for the moment, ok, maybe not God, but at least the head of a talented bunch of programmers, and you can do anything. Is there any logical reason that would prevent you from applying dimensions to a 3D model, and when the dimensions are changed, the part geometry changes to match? It’s such an obvious thing to do, why aren’t people doing this?

Let’s do a little homework. Just assume for the time being that you have a fully “intelligent” SolidWorks model in one window, and in another window, you have that same SolidWorks model, exported as a Parasolid and reimported. The reimported file is what is commonly known as a “dumb” solid. It is imported. It has no features or sketches. It is dumb because you can’t edit it. So right there, side by side, one imported and one native, the same geometry, but one is intelligent and the other is not.

The funny thing about this is that the final geometry, the Parasolid body, is described inside the SolidWorks file in exactly the same way. So the finished model is exactly the same, regardless if it is imported or native. Let that sink in. I believe it’s true, or close enough for our purposes.

SolidWorks currently has a feature called Move Face. It enables you to select a face or set of faces from a solid or surface model, regardless of how the face was created and translate, rotate or offset the faces. This tool has limitations, and the interface is comparatively primitive, but it works, and it works on both native models and imported models.

There are some aspects of the Move Face tool that are kind of funny. First of all, it is essentially a direct modeling tool being used inside a history-based modeling scheme. It creates a history-based feature which resides in the feature tree, and is rebuilt along with the rest of the features. I wrote about this contradiction over a year ago in a post called Stepping outside of the parametric feature-based paradigm with SolidWorks. (If you read that post, it might look like some of my ideas about this have evolved over the last year and a half, and there’s a reason for that – because they have.) There are all sorts of best practice concerns about mixing history-based paradigm and direct editing methods. I’ve heard some top users say bad things about using Move Face, calling it sloppy practice and worse. I don’t disagree. But the fact is that it works, and when it works, it typically saves you a lot of time when compared to the monkeying around that you would need to do in order to do the job “correctly”.

I used to spin my wheels a lot trying to follow arbitrary rules. It took me a while to realize that it is better to have rules you can live with than to just follow rules because they are there. I think the same applies to this Move Face functionality. History-based best practice rules declare that Move Face is an abombination, sloppy, hack-and-whack modeling. So try to imagine a set of rules where saving time and brain power is a good thing.

Just think that if the Move Face interface were improved, and instead of it working through a PropertyManager dialog box, instead you were just able to put a dimension on the model and make changes, think of how convenient that would be. You wouldn’t have to mess with the feature order, or the FeatureManager or parent/child relations. You wouldn’t have to worry about other features failing. This would just be the interface change because the inner workings of the software using the Parasolid kernel to calculate the geometry would still be the same.

So, do you still think that parametrics can’t exist without history? Here’s the kicker. I already knew the answer before I asked the question. The answer is yes, parametrics without history can and in fact does already exist. Check this out:

This model was created in SolidWorks, by the way, but it really doesn’t matter. This is just a teaser. And no, I didn’t use any demo jock voodoo on this. It is just what it looks like it is, putting dimensions on an imported model, and changing the imported model.

There I hope that puts that one to rest. For now you’ll have to trust me that you can do geometric relations as well as dimensions, but if you watch you can see the sides of the rib that are tangent to the top cylinder change when the outer cylinder gets bigger, so it is maintaining tangency, which is done in the Live Rules panel in the upper left. You really can’t see that, but it’s there, and can be either added to or disabled according to your needs. Really, the video just scratches the surface. You’ll see more of this from me in various places.

As a prelude to comparing history-based systems to other types of modeling systems, I want to try to spend some time thinking about history-based systems on their own. Specifically, I want to see if without comparison to anything else, the idea of modeling something based on the software sequentially rebuilding geometry from a recipe has any gaping conceptual flaws.  Most of us have lived with this system for years now, whether it is SolidWorks, Solid Edge, Inventor, Pro/ENGINEER or one of several others. I find it is difficult to be objective about it because I’m admittedly too close to the topic to have much perspective. But unless you don’t use anything regularly or are switching regularly between radically different CAD packages, you’re in about the same boat as me.

If you think back to when you were first introduced to SolidWorks, can you still remember the new concepts and vocabulary you had to learn? You’ve got terms like history, feature-based, parametric, associative, solid and surface modeling, and so on. As I remember it, none of this was particularly intuitive. I thought it was cool once I understood the process, but that’s the first thing to be aware of: that history-based modeling involves a process.

Something that has been slightly mind bending for me is trying to separate history-based nature of contemporary CAD systems from those other buzzwords. For example, can you imagine a CAD scenario that uses parametrics, but not history modeling? How about using features without history? Those concepts may be difficult to imagine if you’ve lived in a history-based world for your whole professional life, but we will get around to having a look at those things. For now, I just want to extract the history part of it and look at that by itself if possible.

If you think about what part of the modeling workflow exists specifically because of the history-based nature of SolidWorks, you think of things like:

• FeatureManager
• reordering features
• rollback
• rebuilds, including waits and errors
• parent/child relations

If your experience was anything like mine, when you were first introduced to history-based modeling the topics above weren’t easy to learn. I know I’m constantly doing battle with each item on the list, even after studying history-based modeling for the past 14 years. I frequently refer to the conflict between draft, fillets and shell as “rock, paper, scissors” (the game where each option can either win or lose depending on what the other player chooses), which is primarily due to the effects of feature order, one of the by products of history modeling.

The main difficulty associated with history-based systems has to do with the fact that the process involved with modeling becomes very important. That’s why people say history-based CAD requires a specialist just to understand the modeling process. There is a lot of validity to this complaint. Getting the right process for different types of models is sometimes tricky. We have become familiar with the term “best practices”. What if there were no such need for best practice, because the only thing that mattered was the final product, not the process by which you arrived at the final product?

How about accepting the idea that the model you really want is the finished model, which is just a set of boundary representation (b-rep) faces created by the software. Do you really care how you got to the finished model, or do you just care about the model itself? Lists of features are one thing, but does (“should”) it really matter what order those features were created in?

If you have ever struggled with parent/child relations between features or feature order or broken relations due to features removed or added while in rollback, you have experienced some of the difficulties induced by the history-based nature of the software. Most of us just accept this as part of the price of waking up in the morning and using history-based 3D CAD software because we don’t know anything else.

To be fair, there are also some advantages of history-based modeling. For example, fillets. Whether or not a modeler remembers the order in which fillets are applied, the effects of applying them in a particular order can be seen in the resulting geometry. A history-based system enables you to deliberately alter that order. It turns out that fillets are simultaneously both a strength and weakness of both history and non-history modelers. This seems like a contradiction, but at the end of this series of blog posts, I hope you will agree with me on this point.

So, like the rest of life, history-based modeling has its pluses and minuses. It is a system that has served us well for a couple of decades, and most of us have been able to figure out how to use it profitably in our businesses. However, there are enough examples of painful experiences around working with history-based systems to consider if there might be some viable alternative out there. That’s what the next blog entry will be about – alternative modeling paradigms.

Sometimes you just need a different tool. No judgment calls about why, you just might for whatever reason need a different tool. I’ve looked at a few CAD tools, and found things that were important improvements over my current tools, and also things that were impossible compromises. After having used mainly one CAD tool for the last 11 years, it can be difficult to be objective about it or alternatives, but I’ll try.

Purpose

What do you need your CAD tool for? You know, not all CAD tools try to be what SolidWorks tries to be. SolidWorks seems to try to be a one-stop-shop. To some extent it succeeds, but sometimes you might just need specialist tools. For example, I’d say that SW is pretty good for stuff like machine design and sheet metal. It’s great for machined parts. SW certainly has capabilities in complex shapes and plastics, but it is far from ideal for these functions. SolidWorks isn’t great at piping or wiring, either, but it does it. I wouldn’t use it for architecture, but you might make it work.

Anyway, here is a little list of things I put together about a few CAD products. I’m not directly familiar with most of these, and I’m not shilling any products or trying to promote any ultimate solution, just talking about alternatives for various purposes. I encourage people with specific experience with some of these products to share what you like or don’t like about the tool, and what kind of work you think it is best suited for. The categories aren’t meant to be definitive, just to give an indication of where I see the tool fitting or not fitting into what I do. The categories certainly oversimplify things. Don’t get worked up about the categories. (Geez, why am I getting defensive about this already? Premonition?) I’m sure I’ve left something out or miscategorized something, and this is the kind of junk that some people get really upset about, so please, no flame war here. I’m looking for considered opinions, not dogma.

General purpose modeling

Complex surfaces (nurbs)

Digital sculpting (mesh)

Simple concept models

 (Moment of Inspiration – MoI)

Architectrure

Reverse Engineering

Rapidform
Geomagic Raindrop
Revworks

===============================

Of these, there are a couple of products that I want to have a closer look at. I’ve used Rhino off and on, but in the next weeks I will try to write about how Rhino can fit into the workflow for a product designer, plastic part designer or complex shape modeling scenario that is somehow tied to SolidWorks.

I obtained a trial license for SolidThinking, a seemingly overlooked piece of software from the Altair company that is involved in some pretty high end software. This looks interesting to me, and could possibly have my type of modeling more squarely in its sights than does SW. Complex surface modeling is at best a niche sideline for SW. For SolidThinking, it appears to be dead center.

Maybe its just the similarity in the names, but Think3 is another product that I get confused with SolidThinking. A recent interview on Novedge rekindled my interest in this product.

Other tools interest me as concept modelers, such as MOI, Shark, and modo. If I had multiple lives to live, I’d love to be a digital sculptor. It’s one of those things that looks like fun, but I’m not sure I could make a living at it.

In conjunction with the digital sculpting is the reverse engineer sofware. Rapidform is one I’ve played with and threatened to do a review of, but have never done it. The connection between digital sculpting and reverse engineering is the point mesh data that both work with. Reverse engineering software enables you to take mesh models from CG/digital sculpting applications and make them into NURBS models compatible with SolidWorks.

modo is hot news these days too because they come from the Luxology company, who is responsible for the PhotoView360 software. I think it is a bit overkill that SolidWorks has sunk so much development resources into rendering, and they have a half complete simple renderer, along with a too-complex, halfway renderer – both about half finished after all of this time of delivering half finished product. It;s like going to my brother’s house. He has 4 construction projects half done. What a mess. Anyway, modo is a newish CG/digital sculpt/mesh modeler, and it looks pretty good.

So you can see I have no end of curiosity, but not near enough time to play with all of this stuff enough to say something useful about it. Any suggestions or favorites from the list for different applications?

SolidWorks Labs has a new widget for plastics design. So far, it is just another data black hole that you throw information down, but the implication seems to be that if you sign up, you may be invited to try out this new offering for plastics designers. Oh, the curiosity! What kind of functionality would be useful to you as a plastics designer? Not just features, but would a whole new way of working benefit shelled plastic parts? Any possible parallels between plastics and sheet metal or weldment environments? Any other ideas?

Have you ever seen the defunct ImpactXoft? In around the 2002 time frame, it was aimed primarily at plastic designers, and is now presumably absorbed by Catia. I saw a demo only once, and it was fairly impressive. I didn’t spend any time researching what was making it all happen, but ImpactXoft tried to drive the idea of functional features. I remember being somewhat skeptical that the software developers could anticipate everything I would want or need to do with plastic features, or make any functionality that was flexible enough to create things that the developers didn’t anticipate.

I generally consider the existing functionality in SolidWorks like the snap, boss, and vent to be primarily gimmicks for the same flexibility/completeness reasons. I welcome attention to plastic design issues, since that is where I spend most of my modeling time, but these attempts don’t seriously answer any real needs for me.

IX did have an interesting approach, that is echoed by much newer software claiming to be revolutionary. Functional features was really the basis for their approach, but it turned out to be a non-history based modeler. This is somewhat different from the feature recognition claimed by Synchronous Technology. Rather than a feature tree, IX used a functional recipe, which was not order dependent.

The SynchTech direct modeling with feature recognition concept would not work well for plastic parts. First, it appears that SynchTech is limited to simple geometry, and plastics often use spline shapes.

I’m not trying to imply that there is any connection between the new SolidWorks Labs project and ImpactXoft functionality, I don’t have any information on that. I’m just thinking of one possible route they could go. ImpactXoft really didn’t go anywhere as a product, I’m presuming because the concept of functional features was not sufficiently developed.

Ok, this’ll get tongues wagging. Now that I’ve learned a little, or think I’ve learned a little about Synchronous Technology, I learn that the only thing that’s really unprecedented about it is the amount of useless jaw movement it has caused.

Check out these Catia V6 youtube videos:

Huh. Well if that doesn’t look an awful lot like ST or SC, I don’t know what does. It seems to be called Catia Live Shape. I have exactly zero actual information about it other than what I can see in these videos, and the Martyn Day article I linked to in a previous post. The second video was posted in March, right before the Siemens media onslaught started. So who is it that is playing catch up? Neither product seems to be truly market ready yet, so it remains to be seen who delivers this first to paying customers.

But the geometry creation tools are only the tip of the V6 iceberg, and not even the tip that the Dassault marketing folks seem most interested in, either. Collaboration, PLM 2.0, Web techniques, virtual immersion, “experience” all seem to be more interesting to DS.

Here’s another one where Bernard Charles explains what PLM 2.0 is all about. I can’t really understand it, but that’s because Mr. Charles Franglish is further slurred by the low quality youtube audio. If anyone figures out what he’s saying, please leave a comment.

So, Catia seems to be more focussed on PLM 2.0, and really big picture stuff more than the small potatoes of making and changing geometry.

And finally, the above piece is I think the most powerful statement they make about V6. The virtual host, with her virtual hand and head gestures, right down to the virtual stretch of her blouse between her virtual breasts. This company believes in this virtual reality immersion in a way that wasn’t possible the first time the VR wave hit almost 10 years ago. The first wave led primarily to the proliferation of games. This wave may lead to the proliferation of industrial simulation.

Anyway, ST is not the only game in town. I think Siemens saw a window of opportunity, and it just happened that the window didn’t correspond to a time when they had a real product to sell. Siemens main hope was to strike first, even if it was just a virtual strike.

I have to admit, I was originally kind of interested in this Synchronous Technology topic, but I’m quickly getting over any sort of interest that I had in it. I’m catching a fair amount of crap for it, and not really getting what I think are very good answers. Since I can’t rely on finding anyone with an objective opinion out there, I’m just going to have to put this on the shelf and wait until maybe someone from Siemens sends me a copy to review (hint, hint).

Siemens has started selling this “pig in a poke” at a greatly reduced price (~$3000 - in a notice from a reseller who spammed some forums). The price seems to suggest that they see Spaceclaim as their main competition, even though they are asking you to “trade in” your SolidWorks license to do it. Of course they can’t actually take your SolidWorks license, so the whole thing is just a stunt.

Another thing that confuses me is you hear these marketing testimonials about how company X is seeing such great improvements, but at the same time you can’t get a straight answer out of anyone who has actually used it about functionality because the software is not going to be available until August.

The fact that no one can really descibe it succinctly in a way that makes sense says everything they need to say about it. So if I can’t get users to say anything intelligible about it, then it remains just another glossy ad with nothing behind it. The part that really irks me is that the people who say I’m just criticising because I’m devoted to SolidWorks are waving the SEwST flag without any personal experience whatsoever. I am at least looking for objectivity.

One of the fellows who posted a comment here sent me a couple of long emails which are equal parts rant, defense of MS Ribbon interface, incorrect memory, self contradictions, and underdog flag-waving. Scott Wertel it seems is a fan of Alibre and Solid Edge. He claims CAD is just a tool, but also defends zealotry. I’m not sure what to make of this contradiction. He claimed I had changed my mind about the SW 08 interface, but later recanted, because he was obviously wrong about that.

Anyway, this is really long, but it explains a few things. I’m trusting that Scott’s one view of this stuff was enough to give him the correct impression. Here is what Scott had to say, with comments interspersed:

===============================
Religious zeal

I’ve been guessing a lot about what functionality the term Synchronous Technology was meant to obfuscate. I’ve been both wrong and right about some of my guesses. I’m not the only one. Even Evan Almighty has been wrong and right, but mainly irrelevant. Very few people have any real “facts” about this stuff. We hear what some people want to be true, and some people just blindly repost press releases without any idea at all what it means. We’ve heard some strange emotional rants about why the world needs something like this as opposed to something or anything else, and some equally strange posts seemingly defending SolidWorks from the need to keep up with the Joneses.

I’ve been lucky enough to have Dan Staples of the Solid Edge development team and Chris Kelley, a Siemens marketing guy both stop by the blog here and leave some comments. Dan in particular has been very helpful with the only hard facts I’ve heard anywhere about Synchronous Technology. Even the ST white paper is very heavy in vague declaratives. The truth is that most of those videos posted about ST, well, I’ve been tempted to post equivalent videos of SolidWorks doing exactly the same thing. Not because I have an axe to grind, but just to show that the examples we have seen of ST have been unconvincing because the capabilities already exist in SW and other places. This is why some folks have said ST is nothing new. I think Siemens has done a wonderful job of creating hype, and a less than wonderful job of backing it up. But of course that may be the main attraction of hype – not backing it up is what makes it hype in the first place.

So what have we learned?

- Synchronous Technology means that all of the relations in a part are solved simultaneously instead of linearly.

In SolidWorks, mates in an assembly are all solved simultaneously. So are sketch relations. These are driven by D-Cubed, also owned by Siemens. What are two of the least reliable areas of the SolidWorks software? You got it, sketch relations and mates. Go back and count how many times I’ve singled those two areas out as things I would like to have fixed. I think this is a bad omen for ST. D-Cubed proves that simultaneous solutions are not an incredibly reliable source. Of course SW’s problems could be an implementation issue, and it still remains to be seen how Solid Edge’s implementation of simultaneous solutions for relations within a solid model is going to work in real every day modeling.

There is no doubt, history can be a cumbersome way to create geometry, but it is also just as often a great asset when making changes. Getting away from history is a great theory, but based on what I’ve seen of simultaneous solutions, there may be a reason why other CAD companies are not flocking to it.

- Synchronous Technology really is something new – a new way of putting together a lot of old stuff.

“Synchronous” can mean “solving relations simultaneously”. Or it can mean integrating several modeling technologies or techniques. I think the “synchronous technology” term benefits from some intentional double entendre, but at the same time is sufficiently vague that it doesn’t mean anything in specific as a stand alone phrase. All of this probably makes sloganeering marketing people wet their pants in glee. Still, clever new names or not, this is all familiar territory.

Simultaneous solutions? Check. D-Cubed. Shaky foundation. Been there, done that.

Driving dimensions and geometrical relationships on “dumb” geometry? Check. Spaceclaim.

Feature recognition? Another shaky foundation. Check. Several CAM products use this, as well as FeatureWorks.

Live Rules? Behind the marketing name, this is indistinguishable from parametric relations. In fact, it looks much like parametric relations applied directly on the solid model. Dan sort of confirmed this, I think. Parametric relations on a solid model to me is the one thing to really get excited about with ST. The screen grab below was taken from a youtube video.

- Siemens is totally changing directions in the high end and midrange markets, and is throwing this Hail Mary in the hopes that all the commotion may attract more attention than all of the Spaceclaim and CoCreate non-news.

With Synchronous Technology, Solid Edge has removed itself from the SolidWorks – Inventor fray. They have been removed for some time, they just never admitted it until now. Personally, I think the hype has been brilliant, but the failure to follow up the hype with some sort of intelligible scheme that real users can understand leaves the whole thing looking like the vacuum cleaner salesman saying “trust me!!” It’s kind of telling that I had to dig this info out of people, and that Siemens clearly does not have a clear and intelligible message for users.

Chris Kelley appears to be a one-man Solid Edge blog machine, but he is marketing, not technical. Really, are there any technical Solid Edge blogs out there? Why are they not giving us the low-down from a users point of view (or are they and I’m just not seeing it?) I’m not bashing Solid Edge as a product, I don’t know enough about it to bash it. It seems so much like SolidWorks as to be practically the same, historically, anyway. But the product hasn’t seen the broad industry acceptance that SolidWorks has seen, so Siemens had nothing to lose by changing the rules and aiming low.

What I mean by “aiming low” is that the whole direct editing movement seems to be enthralled with the ease of use idea. I think this is meant to expand the definition of a “CAD user” to mean someone lower on the specialization totem. The message here is “ease of use” rather than “power” or “control”. These ideas always seem to be diametrically opposed.

- What remains in Solid Edge is no longer a history based modeler.

Some people who don’t know (including me) have said that ST is Spaceclaim bolted on to SolidWorks. I don’t believe this to be the case. I’m now under the impression that ST is Spaceclaim bolted on to CoCreate, or there abouts. There is no history left. Siemens has abandoned history based modelers. This seems to be one of the things that Dan was saying.

Many UG users I have known have said that UG never was much for history based modeling, and with Solid Edge showing as an “also ran” in the parametric history based market space, it is no surprise that they decided to changed direction, possibly if for no other reason than to distinguish themselves from SW and IV. So now they have a chance of being on the top of the heap of non-history based modelers, and trying to capitalize on the wave of direct editing modelers really rejuvenated by the popularity and simplicity of Sketchup, and given a shot in the arm by Spaceclaim.

Summary

Solid Edge and Unigraphics/NX are both strong products, but they aren’t market leaders. Solid Edge was acquired from Intergraph, and part of NX is SDRC. How is Siemens going to grow this set of products? A bold move like completely rearchitecting the software might not have been inevitable, but it really isn’t a huge surprise.

I’m very interested to see what rank and file Solid Edge users think of these changes. For those that are happy with the history-based view of the world, Solid Edge may have just handed SolidWorks a small infusion of new customers. There are several people who are not paid by Siemens who are going around claiming that this stuff is the answer to all their prayers, even though they have never laid hands on the software or fully understand how it really works.

I’m going to guess that the new Solid Edge will have a little burst of sales just due to curiosity, but in the end, interest will wane. There is a reason why products like IronCAD, CoCreate, KeyCreator and Spaceclaim have not become overwhelmingly poplular while products like Pro/ENGINEER, SolidWorks and Inventor have. I don’t think a massive hype campaign is going to be enough to change this decades old momentum.

It may be a great idea, and it may have required some revolutionary thinking to bring it to fruition, but I think Synchronous Technology is going to become another forgettable buzzword that marked a sharp turn in the road for an “also ran” history based modeler.