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  #1  
Old 04-17-2007, 06:38 PM
49again 49again is offline
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OneSpace vs. SolidWorks

I have downloaded and looked over this OneSpace PE software, and have checked out some of the tutorials and webinars.

I've been a heavy duty SolidWorks user for ten years, I have a good idea what it can and cannot do. From what I've seen so far, OneSpace LOOKS very good.

Is there anyone in this forum that has a good feel for both of these CAD packages that could give me their opinion as to whether it would be worth my while to spend the time to become proficient enough with OneSpace that would eventually make me want to switch? I don't need to look at this in light of having a "more rounded" skill set. If someone could convince me that it would be worth my time, then I would definitely take the time. Otherwise, I've got plenty I can be doing with SolidWorks. Add to this that I would also want to convince the other three guys in my department at work that this would be a wise switch to make.

SolidWorks does fairly well for us, although it seems to get bogged down a bit on some of our larger and more mechanically complex assemblies. I'm just wondering if the grass is truly greener on the other side of the fence......

Thanks for your time and thoughts,

Steve R.
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Old 04-17-2007, 08:05 PM
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dszostak dszostak is offline
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Re: OneSpace vs. SolidWorks

If you are interested... Register for the complimentary Getting Started with CoCreate OneSpace Modeling PE Webinar and get your questions answered, after the 30 minute demonstration, by two expert CoCreate CAD Engineers.

Register for the CoCreate Webinar at www.cocreate.com/webinars.

As for the CoCreate User Forum, there are a lot of threads on this topic:

* Cadalyst - MCAD Modeling—History . . . or Not?
* Desktop Engineering - Geometry is King for OneSpace
* Machine Design - Comparing 3D CAD modelers
* Design News - Cool Software Trick
* The CoCreate Dynamic Difference Webcast
* SolidDesigner Vs SolidWorks (OneSpace Modeling was previously known as SolidDesigner)
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Last edited by dszostak; 04-17-2007 at 08:58 PM. Reason: Fixed URL links
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  #3  
Old 04-19-2007, 11:09 AM
Marten Marten is offline
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Re: OneSpace vs. SolidWorks

About three years ago, we chose One Space designer over SolidWorks (we compared SW 2005 with OSD 12). We did an extensive research, sent our engineers to a training for both applications, and we did a few projects in both SolidWorks and OSD. The main reason we chose for OSD, is dynamic modeling (and related advantages):
  • OSD is easier to use. This became very clear, because our engineers could do complete projects in OSD by them selves after a short training, and for SolidWorks we needed to hire an experienced SolidWorks user.
  • Engineers can modify and use models created by others without the need to study the structure and modify relations.
  • OSD was much faster (and has a lot smaller documents (MB)).
  • OSD was more stable.
  • It was easier to create our sheet-metal parts in OSD.
  • It is easier to program in because you don't need to take a models history into account when creating automated procedures.
It wasn't easy to make the choice, because before version 12, OSD was lacking a user-friendly interface and appeared outdated, and SolidWorks is more of a 'main stream' application and seemed to be the big winner in the market place.

But we never doubted our choice and are very pleased with OSD (and the progress they are making ever since).

So I would definitely recommend you to invest some time. As you are a long time SolidWorks user, I think it will take some time to get used to a completely different approach of working with 3D models, but it will definitely be a worthwhile and fun experience, even if you don't switch.

Good luck!

With kind regards,

Marten Verhoeven
Van Beek B.V.
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  #4  
Old 04-19-2007, 02:49 PM
May Kung May Kung is offline
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Re: OneSpace vs. SolidWorks

One point I'd add to Marten's comment about file sizes being smaller is this carries over into needing less horsepower to model the same things in OSD over SW. With bigger file sizes, you need more RAM (or deal with a really slow system). I suspect OSD is coded more efficiently so it can make do with less. From what I've seen here, we need about double the computing horsepower to model the same kind of parts since we've converted from OSD to SW.

I still use OSD for quick modeling jobs because it's much more flexible during the initial design process. Once a design looks more stable, I'll port it to SW. I know I'm not the only engineer here that does that, although I suspect our management would frown at that.

I would also add it's much, MUCH easier to customize OSD than SW. I can write LISP scripts or just record macros, drag-and-drop them to test it, and then share easily with others. To customize SW, I'd need to learn how to hack the registry if I wanted to share customizations. I used to easily write new goodies for OSD and then put them on the network share so all engineers would see them the next time they started OSD.
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Old 04-21-2007, 03:41 PM
49again 49again is offline
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Re: OneSpace vs. SolidWorks

Thanks to all three of you for your input.

David, I have seen the webinar, and I even sent for the Webcast Center disks that are available. The threads you pointed out were interesting reading, too.

Marten - if your company selected OneSpace over SolidWorks because of its ease of use, well, then OneSpace must be EXTREMLY easy to learn! Several years ago when we switched from AutoCad to SW, I was amazed at how easy it was to use. This makes me think that jumping in to OneSpace should be a piece of cake! Maybe I should not be worrying so much about "wasting my time."

May, you brought up a point that I had been suspecting anyway....the power required to operate both systems. That's one of the reasons I've been looking to see if the "grass was greener" with some other software. SolidWorks is a fantastic tool, but sometimes we get into some designs that are maybe not all that big or complicated, but when we need to get those designs into a paper format - well - let's just say that regenerating some of these drawing views is not exactly what you'd call "instant."

So, consider me "jumping in" to see how this will help me out.

Steve R.
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Old 05-02-2007, 01:37 PM
Steve Steve is offline
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Re: OneSpace vs. SolidWorks

Hi Steve,

In my opinion, once you have used an "intelligent" modeler you will never be satisfied with a "dumb" modeler.

I started using CAD back before solid modeling was commonly available, and cut my teeth on solids using Unigraphics somewhere around V8 or V9. At the time, UG was a Boolean modeler very much like CoCreate is today - all geometry manipulation was done by moving or deleting faces, or gluing on or hacking away parts of the model via Boolean operations. There was no real way to embed intelligence into the model.

Of course it was not long and solid modelers evolved to allow you to create relationships between geometric entities. This, in my opinion, is one of the main features of CAD - the ability to define relationships between geometric entities so that the operator (and future operators) does not have to remember them and manage them manually.

Once you have used software that has that kind of ability, it is very frustrating to go back to software that does not have that ability. For example, let's suppose you have a cylinder of 1 inch in diameter. In CoCreate, if you taper that cylinder, the system forgets that there ever was a cylinder there - it now sees the body as a conical body. So if you want to change the underlying diameter, you can't. You must either delete the taper, change the diameter, and then re-apply the taper, or you must do trigonometry to figure out how far to offset the conical surface to achieve the new desired base diameter. The lack of history means the lack of ability to control the geometry by theoretical foundations.

Moreover, the problem with the non-history-based approach to geometry manipulation is when the model fails to regenerate (and this happens with all software if you attempt to modify the model in such a way that the system is unable to compute a solution) you have no idea what is causing the failure. When a history based model fails, the system tells you precisely what features are failing and to some extent guides you in what you need to do to fix the problem. When a Cocreate model fails, basically you are left with a simple error like "Cut too complex" or "Unable to reapply blends" - and that's all you get. Now as you gain experience you will be able to look at the model for "trouble spots" that are probably causing the model fits, but even then you must manually delete the troublesome geometry that you guess is causing the problem until you deconstruct the model the the point that you can make your desired change. Then you get to reconstruct what you deleted to get to that point.

It has been stated that Boolean CAD tools are simpler to use. That is probably true, because the user is shielded from having to understand embedded logic. Unfortunately, the solution to protect the user from this embedded logic has been to simply gut the functionality altogether. It is much like taking the tires off of my car and then telling me how great it will be since I won't have flat tires anymore. Well, true, but it won't drive so hot, either.

In my opinion the tradeoff is simple: With history, parametric based systems, you may indeed have to think hard from time to time when your model fails and you have to debug a failed internal relationship in the model. With non-history, non-parametric based systems, you have to think hard all the time because you and everyone behind you will have to understand and maintain all the design relationships manually.

If you absolutely have your heart set on playdough modeling, though, you might also want to check out SpaceClaim (www.spaceclaim.com). It may have an advantage in that at least it appears to have been created from the ground up as a new software package, whereas I always had the impression with CoCreate that it was a 3D modeler that had been cobbled together with their legacy 2D product, as the integration between modeling and drafting felt poor, though they have been making improvements over the four years I used it.

Steve

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  #7  
Old 05-02-2007, 02:07 PM
Steve Steve is offline
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Re: OneSpace vs. SolidWorks

Steve:

You might also be interested in this thread:

SolidDesigner Vs SolidWorks
http://www.cocreateusers.org/forum/showthread.php?t=5781

Steve
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  #8  
Old 05-03-2007, 06:41 AM
49again 49again is offline
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Re: OneSpace vs. SolidWorks

Steve -

Thanks for your input. I cut my "3D teeth" using AutoCad. It worked, but it was very painful sometimes getting to where I wanted to go. It was definitely what you'd call a "dumb" modeler (if a hole was in the wrong place, you couldn't just move it, you had to construct a cylinder and add it to your part to fill the hole back up, then create a new hole), and when we switched to Solidworks many years ago, it was like a ton of bricks was lifted from my shoulders - such freedom!

Now, I certainly don't see the same restrictions with OS, but I will keep your point in mind during my evaluation. I'm trying to get enough of my projects already started with SolidWorks done so I can hopefully find out what OS has to offer. My greatest interest is in what May pointed out....does the benefit of history-based outweigh the extra overhead of computer hardware requirements?

The really nice thing that CoCreate has done is to not time limit PE. I don't have the luxury of dropping everything I'm doing to try out a "30 day trial" of different software, and I'm an old enough goat (I won't go into how many times I've been "49 again") that I can pick up a different way of doing things fast enough to get a good feel for a software's value by just clicking through a demo part or two.

Thanks for taking the time to offer your opinion, Steve.

Steve R.
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Old 05-03-2007, 12:27 PM
Marten Marten is offline
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Re: OneSpace vs. SolidWorks

Hi Steve,

In my opinion, the trade off is simple too. Why take the time to always think about the design-rules and add them, when you most likely don't need them?
With history based modeling you have to think hard all the time, when you are creating a model. You have to think: how would this model be changed in the future, because if you don't build the model in an appropriate way, it will be harder to modify. This won't be a big problem for easy parts, but it will be a big problem with complex machines.

When you are designing a machine, you have to add design-rules on every part, even when there aren't any. For example: you model a flat metal part of 500 mm long. Then you add 5 holes evenly divided, in a linear direction. Which design rules do you add here? Is the line of holes always centered to the model, or is it always on the same distance to one side? How many holes are needed? When I make the part 1000 mm long, do I still need 5 holes, or do I need more? When you are creating the part, you can't answer these questions, because you don't know how the part will change in the future.
How these holes are positioned, and how many you need depend on how you are going to modify it. So when you need to modify this model, you still need to think about how these holes need to be positioned. Where is your 'advantage' of the history in the model? It did take more time to add the rules, and now you even have to dig into the models history to find out how you can modify to get what you want. Again, this takes extra time. But you aren't finished yet. After you have modified the model, you have to check if other parts didn't modify in an unexpected way. The part that is bolted to this model, did it stretch when you stretched the model, or did it move, or didn't it get changed in any way while it should?

All this burden is even more restricting when you are designing completely new machines, where you don't exactly know how it will look and function. You will likely change a lot during the design process, and you constantly need to think about the design-rules, even if you don't know (yet) what they are. And because it is a history based modeler, you have to invest the time.

Now another example. You created an assembly a while ago, and now need to create something similar, but nonetheless different. If you use this model in a history based system, you also 'inherit' the design-rules a.k.a. history. For this new assembly, these design-rules probably don't apply, but you still have to study them and modify them in order to modify to model the way you like.

I don't think this is the smart way. Keep it simple! That is the smart way.

In your post, you have the example of the cylinder where a taper is applied to. In order to modify the diameter in the history-based system, you have to know how the model was created, or you have to study the history to find out. Is the conical face created by a taper, or is it created by revolving a cross-section? This stipulates the way the model needs to be changed. In OneSpaceDesigner you need a few commands to do this. The offset-command can be enhanced in order to make this easier, but you definitely don't need to do trigonometry accomplish it. (You can un-taper, change diameter, re-taper or you can draw the new diameter on a workplane and offset the face while using measure to determine the distance.) It's not as hard as you pretend.
There are examples where a change can be implemented faster in a history based system, but generally speaking, I don't think this is the case. The change has to be 'in line with' the history in order to stand a chance to be faster.

In your post, you say: "when the model fails to regenerate (...) you have no idea what is causing the failure. When a history based model fails, the system tells you precisely what features are failing and to some extent guides you in what you need to do to fix the problem.
I don't think this is a good comparison. A history-based system tells you precisely what feature is failing down the history-path. The versions of SolidWorks I used didn't tell you why that particular feature failed either. A dynamic modeler doesn't tell you what feature, because there is no history-path to a feature that fails because of the modification you made. The only feature which will fail is the 'feature' (=face(s)) you are working on. Why it fails isn't always obvious, but the same goes for history-based systems. The fact that the software has got a history isn't the reason why the software can or cannot tell the user why a feature creation/modification fails.
The only thing a dynamic modeler doesn't have to do is point to a feature that fails, because you just modified another feature up in the history-path.

I learned 3D CAD with history based modelers (I-Deas and Pro-engineer). I though it was great, but I quickly encountered 'problems' with it. If you want to change a design rigorously, the system needs to re-calculate the complete history. It probably encounters many problems, which you all need to 'debug'. With a history-based modeler, you are more of a programmer than an engineer. It is a completely different way of thinking, which not every engineer masters. I don't have a problem with that, because I am a programmer, and I 'understand' the software and quickly find out what is wrong. But not everybody can do that. Even if you 'understand' the software, it is a lot of extra work which I don't like to do.
With history based modelers, a simple change (from an engineering point of view) can have dramatic consequences for the time you need to implement the change. Especially if you didn't create the model. With dynamic modeling, you can better estimate how much time it takes to make a change to a model you didn't create yourselves.

So, in my opinion, dynamic modeling is the smarter option, most of the time. OneSpaceDesigner has added parametric functionality to some instances where history makes sense, like creating an array of taped holes, which you can modify later by changing the parameters.
If you like the option of always having both technologies available, you can use HiCAD. We didn't choose it, because it lacks good programming possibilities and a flexible PDM system, but it is a nice solution. Because we hardly ever need history, we had no problem choosing OneSpaceDesigner.

With kind regards,

Marten Verhoeven
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Old 05-05-2007, 11:25 AM
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John Scheffel John Scheffel is offline
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Re: OneSpace vs. SolidWorks

I think it is important to point out that OneSpace Modeling does provide the option of adding some design intent or more "intelligence" to 3D models. You do not have to define your design intent, but you can.

The optional Parametrics module can be used to define relationships between elements (faces, edges, etc.) within a part. For example you can specify that a hole should be a certain distance from a face and that relationship will be maintained as you modify the part. You can move the hole relative to the face by editing the relation.

The optional Assemblies module can be used to define relationships between parts in an assembly so that they maintain their orientation when the parts are moved or modified. It can also be used to simulate the motion of cams and mechanisms, check clash as parts move and create animations.

Both are included with the optional Advanced Design license, which adds other capabilities as well.

If it is possible to draw a conclusion from this thread, or any of the other endless debates on this topic (several are linked above), it may be this...

No current 3D CAD application is the best choice for everyone. All have advantages and disadvantages and proponents who will argue that their CAD is the best. Although it is good to solicit the opinions of others, you should not choose your CAD based only on those opinions. They are just opinions and may be biased by the way that person thinks about design or the type of design work that they do. You need to try them yourself (as 49again is doing) to determine which you like best and which works best for your design needs, especially how you may need to modify your designs in the future.

Although you should try the current popular 3D CAD, you should not chose one just because it is the most popular. Many people chose Pro/ENGINEER back when it was all the rage, only to find that it was not a good solution for their needs. Today SolidWorks is all the rage. Five years from now, who knows?

Anyway, that's my opinion.

For the new members and guests reading this thread, you can download CoCreate OneSpace Modeling Personal Edition for free from www.cocreate.com/free and try it yourself. You can probably get free trials of other 3D CAD tools as well from their web sites.
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Old 05-07-2007, 06:58 PM
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Ron Keeley Ron Keeley is offline
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Re: OneSpace vs. SolidWorks

I encourage folks to look at a brand new 3D CAD Modeler from SpaceClaim. I say this not to suggest that you necessarily jump from OSM to SpaceClaim, but to reinforce the value of dynamic modeling. SpaceClaim - the newest 3D MCAD system on the market (and thus able to design what they feel is the best direction for a new 3D modeler). The CEO is a co-founder of PTC and SolidWorks, and the VP or R&D was also a PTC co-founder. Did they create another history-based, parametric modeler? No, they didn't. They created a system, as written by Martyn Day, that "overcomes the limitations of ‘Features’, ‘History Trees’ and ‘Parametric Constraints’ but makes the modelling of complex forms easy."

I find it very interesting that these folks, with their background and understanding of history and parametrics based MCAD system, chose to create essentiallly another "dynamic modeling" MCAD system. I also think that CoCreate needs to look very seriously at the UI and the methodologies employed ("hints", "mirrors", "SmartTools", "PowerSelect", etc), as they truly appear to make the tool very dynamic in nature.
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Old 05-08-2007, 07:53 AM
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Ron Keeley Ron Keeley is offline
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Re: OneSpace vs. SolidWorks

Here's the most complete information that I found on the SpaceClaim web site in reference to their tools. It really helps to explain things like their gemetric inferencing, their sketch, move and section tools, SmartTools, Hints and PowerSelect, Tool Guides, "Heads-up" Display, Combine, Edit as Blend, Mirror, Shell, Offset, 3D Mark-up, Model Compare, etc. All these things seem like excellent aids for a dynamic modeling system (hint-hint).
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Old 05-08-2007, 08:33 AM
Marten Marten is offline
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Re: OneSpace vs. SolidWorks

I'm glad they aren't all new. Edit as blend and 3D-Mark-up are already available, and since version 2007 Model Compare is also available. But, Cocreate should definitely take a look. Even if they don't implement the features, they could initiate new ideas for OSD. If you find more detailed information, please post them also:-)
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Old 05-22-2007, 02:57 PM
Steve Steve is offline
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Re: OneSpace vs. SolidWorks

Marten:

Quote:
With history based modeling you have to think hard all the time, when you are creating a model. You have to think: how would this model be changed in the future, because if you don't build the model in an appropriate way, it will be harder to modify. This won't be a big problem for easy parts, but it will be a big problem with complex machines.[
Actually, your thought process should be like that of anyone who is considering the fit, form, and function of a part they are designing: "What relationships are important about this particular geometric feature?

Yes, this takes careful thought with the creation of each feature - as it should if you are a careful engineer. Not a single face exists on a part without a purpose, or you would not have put it on there. Why not capture what that purpose was?

Quote:
For example: you model a flat metal part of 500 mm long. Then you add 5 holes evenly divided, in a linear direction. Which design rules do you add here? Is the line of holes always centered to the model, or is it always on the same distance to one side? How many holes are needed? When I make the part 1000 mm long, do I still need 5 holes, or do I need more? When you are creating the part, you can't answer these questions, because you don't know how the part will change in the future.
It isn't so important how the part will change in the future, but rather, what is the current design intent.

If your design intent is to have 5 holes evenly divided along the length of the part, you parametrically establish that sort of pattern so that no matter how the part length changes, you will always have 5 holes evenly divded in that linear direction.

If your design intent is that the holes need to be centered to the model, then you establish that relationship.

If your design intent is that the holes need to be on the same distance to one side, then you establish that relationship.

If you don't know how many holes are needed if the part grows in length, then you have an engineering problem, not a CAD problem. Once you have determined the engineering requirement, then you can set up your model so that when the part is, say, less than 1000mm long you have 5 holes, and if it is over 1000mm you get 6. Or you can even set up a relationship to drive the hole array to achieve a certain "negative area" - the amount of open area the holes are required to provide based on the number of holes present and their size.

If you can't answer these questions at any particular time in the design - NO PROBLEM - you don't HAVE TO. Many parametric, history-based software packages such as Solid Edge, Solid Works, and others don't require the constraining of sketch geometry in any way. The point here is not that you have to create design relationships in your geometry, the point is that you can. I tend to lock things down just as soon as I am able. Why? Because I can forget about them from then on and they will take care of themselves.

Quote:
How these holes are positioned, and how many you need depend on how you are going to modify it.
Absolutely, 100% incorrect. How these holes are positioned, and how many you need depends on engineering requirements, and is completely unrelated to the CAD software. The point here is that once you have defined the engineering requirements, parametric software allows you to capture those requirements.

Quote:
Where is your 'advantage' of the history in the model? It did take more time to add the rules, and now you even have to dig into the models history to find out how you can modify to get what you want.
Well, the way I see it, it's the "pay me once now or pay me forever" problem. You can either take the time to codify the engineering requirements once such that the geometry flexes while obeying those requirements, or you, and every future designer can manually maintain those relationships with every model change forevermore.

Quote:
But you aren't finished yet. After you have modified the model, you have to check if other parts didn't modify in an unexpected way. The part that is bolted to this model, did it stretch when you stretched the model, or did it move, or didn't it get changed in any way while it should?
Certainly it is true that if the engineering requirements were not correctly codified in the model it will not flex properly automatically. Of course it is also true that without the ability to capture engineering requirements at all your model will never flex properly automatically.

Quote:
All this burden is even more restricting when you are designing completely new machines, where you don't exactly know how it will look and function. You will likely change a lot during the design process, and you constantly need to think about the design-rules, even if you don't know (yet) what they are. And because it is a history based modeler, you have to invest the time.
As I said above, many parametric modelers today do not require creating design rules. In this regard they will function much like CoCreate - you just leave off the parameters. Yes, the history aspect of the model means that some features may be dependent on previous features and this can be annoying during editing of the model. The good news is you can generally re-order features fairly easily.

Quote:
Now another example. You created an assembly a while ago, and now need to create something similar, but nonetheless different. If you use this model in a history based system, you also 'inherit' the design-rules a.k.a. history. For this new assembly, these design-rules probably don't apply, but you still have to study them and modify them in order to modify to model the way you like.
Yes, this is true, and logical. If new design requirements are in play, then the geometry will need to be modified to obey the new requirements.

Quote:
n your post, you have the example of the cylinder where a taper is applied to. In order to modify the diameter in the history-based system, you have to know how the model was created, or you have to study the history to find out. Is the conical face created by a taper, or is it created by revolving a cross-section?
No you don't. You just double click on the geometry right on the screen, and the appropriate dimensions light up right there for you to edit. You can instantly see whether you are dealing with a taper or a revolved section, and, either way, directly edit the taper angle or the underlying untapered feature.

Quote:
In OneSpaceDesigner you need a few commands to do this. The offset-command can be enhanced in order to make this easier, but you definitely don't need to do trigonometry accomplish it. (You can un-taper, change diameter, re-taper or you can draw the new diameter on a workplane and offset the face while using measure to determine the distance.) It's not as hard as you pretend.
It is exactly as hard as I "pretend". If you want to change the basic diameter of a tapered cylinder in CoCreate you have two options: Untaper the cylinder, change the cylinder diameter, and then taper it back, or do trigonometry to determine the normal offset. Drawing a circle on a workplane normal to the cylinder axis will not help you because measuring the distance from the conical base to the circle will not give you the normal offset required to hit that circle. Deleting the taper (untapering the cylinder) and reapplying it is not as efficient as simply directly editing the underlying basic diameter, not to mention all the drafting havoc you create for dimensions and such that were tied to the taper.

And the heck of it is, this is a trivial example of the problem. Try modeling up injection-molded or cast parts of any complexity at all and then have a need to go back and modify the underlying basic cavity sizes that have all been lost under drafts and blends and you will find yourself pulling your hair out. I know from experience.

Quote:
A history-based system tells you precisely what feature is failing down the history-path. The versions of SolidWorks I used didn't tell you why that particular feature failed either.
I've never used SolidWorks, so I can't speak to it. But in both Pro/Engineer and Solid Edge, when a feature fails, it usually provides some diagnostic information as to what is causing it to fail. At the very least, though, even if you want to follow the hack-and-slash method of deleting problem features rather than fixing them, like you have to do in OneSpace Designer, at least you know which features to delete.

(continued)
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Old 05-22-2007, 03:00 PM
Steve Steve is offline
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Re: OneSpace vs. SolidWorks

John:

Quote:
I think it is important to point out that OneSpace Modeling does provide the option of adding some design intent or more "intelligence" to 3D models. You do not have to define your design intent, but you can.

The optional Parametrics module can be used to define relationships between elements (faces, edges, etc.) within a part. For example you can specify that a hole should be a certain distance from a face and that relationship will be maintained as you modify the part. You can move the hole relative to the face by editing the relation.
The parametrics module in OneSpace Designer is so weak that you are limited in the parameters you can apply. The tapered cylinder example is a classic, trivial example of the shortcoming. If you have relatively primitive geometry, with lots of planar faces and edges for applying parameters to, then you may have some success with them. But if your parts are drafted and radiused, the theoretical intersections you would like to dimension to don't exist as far as the modeler is concerned, and you can't apply parameters to control them.

Not only this, but the parametrics in OSD are pretty much an all-or-nothing proposition. Unlike feature-based modelers, where you can simply click on a feature and the relevant parameters will light up on-demand, with OSD they are always visible. Yes, there is a browser window you can use to turn off and on individual parameters but unless you have given meaningful descriptions to each parameter it is difficult to tell in the browser which parameters go with which feature(s) on the model.

I found the parametrics so cumbersome to use that I, a parametric freak, gave up using them in OSD.

Ron:

Quote:
I find it very interesting that these folks, with their background and understanding of history and parametrics based MCAD system, chose to create essentiallly another "dynamic modeling" MCAD system.
I'm not surprised at all, especially after watching their webcast debut. Basically their market studies have indicated that 4/5 of potential CAD users can't figure out how to use embedded logic in 3D models. So they are going after that segment of the market with a less sophisticated, easier to understand CAD tool. There's no doubt or argument that Boolean CAD tools are simpler to use than parametric ones. It's a question of power. My guess is that companies like CoCreate and SpaceClaim have found that the power-user market segment is effectively saturated. So they're going after the users who don't presently want, need, or understand how to embed logic into their designs. Unfortunately, eventually you reach the point where you do want to embed logic into your design, just like they did back in, oh, 1992 or so, and you find the limitation of Boolean CAD software.

Steve
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