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IronCAD

2014 IronCAD Design Collaboration Suite Now Available

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IronCAD, LLC announce the release of the 2014 IronCAD Design Collaboration Suite (DCS). This new release delivers new productivity and collaboration capabilities that reduce the overall time in the design process and enhance data sharing among the thousands of companies and engineers worldwide using IronCAD’s Design Solutions.

The new 2014 IronCAD Design Collaboration Suite of products brings not only customer driven improvements in the design capabilities, but enhances the way customers can collaborate within design groups and with their customers. Users can share data between the IronCAD suite of products that can be leveraged at any level within an organization as well as online with the GrabCAD community and online customer projects. Using the integration with KeyShot, customers can quickly and clearly communicate designs in bid proposals and technical documentation shortening the collaboration cycle while delivering to customers’ expectations.

IRONCAD XG

Key highlights provided in the IronCAD DCS 2014 include:

Delivering Productivity

  • Intelligent Editing of Multiple Part Features: It’s common in design to make changes where multiple features that are on the same part or across different parts must adjust by the same amount. With the new capabilities added, users can simply select all the features to be changed and pull a single handle to perform the modification, reducing the need to build complex parametric relations.
  • Simple Replication of Parts/Assemblies: Patterns and related features (i.e. links) are used throughout the design to create multiple features in various locations. Typically other parts will be generated to align to these feature locations. In the 2014 IronCAD DCS release, users will be presented with on drop options to replicate the parts/assemblies along these feature locations making it simple to rapidly place these objects in the proper location.
  • Behavior Driven Activation of Features: Often users wish to define specific ways in which an object is modified when first applied as a feature or new object in a design. Now users can set specific handles on drop to be active allowing users the ability to directly input driving values. This reduces the time involved to edit features and provides a simpler way to set the desired default editing behaviors on objects.
  • Automatic Constraint Connections on Drop: In some designs, it is required to define the way in which objects move in relation to other objects. New intelligent options have been added to automatically define these relationships at the time an object is dropped onto an existing object. A simple example would be an automatic coaxial constraint being applied to a fastener dropped into an existing hole location.
  • Intelligent Sizing Handles: When sizing geometry, users may find it difficult to precisely modify the geometry to locations on other objects (such locations may be hard to reach by cursor location in the 3D environment) or they may not understand the rules that define how an object can resize to these locations. New behaviors have been added to allow intelligence to be defined on handles so that they can be quickly resized to these exact locations in other objects by a simple right-click command. Users can simply hit any point near the desired location and they are confident that geometry is precisely sized correctly.
  • Re-engineer with Ease from Existing Geometry Data Including Point Cloud Data: Facet based objects and scanned point cloud data is becoming a common utility in the re-engineering process. IronCAD Solutions support the import of these often extremely large data sets in an optimized working environment while providing quick creation tools to recreate geometry referring to this data.

Enhanced Collaboration and Sharing

  • Fast, Easy, Accurate Visuals with KeyShot: Users can now quickly transfer and update designs directly into Keyshot to use their award winning rendering capabilities to quickly produce realistic visuals for communication in bidding, final presentation, and technical documentation of products.
  • Online Collaboration and Sharing with GrabCAD: The IronCAD Design Collaboration Suite today provides real collaboration by enabling users to communicate design data seamlessly throughout their design process within their organization. The GrabCAD Integration is a natural extension for our solutions that offers customers the ability to directly share files and projects within their online design groups and with the GrabCAD community at a simple touch of a button.
  • Direct Access to Components on TraceParts: Users typically require standard or purchased parts to be used in their designs. With the TraceParts integration, customers have access to hundreds of supplier catalogs and over 100 million CAD models and product datasheets suitable for the design, purchasing, manufacturing and maintenance processes.
  • Live Design Modifications between Rhino and IRONCAD: IronCAD has had a long standing connection with Rhino to provide the ability to make use of Rhinos strong surfacing capabilities. User can edit design features from IRONCAD in Rhino that may require more complex surface alterations. These edits will be automatically update in IRONCAD while maintaining existing relations to these modified features. This capability has been extended to support the latest versions of both IRONCAD and Rhino giving user the most recent advances to create and edit their designs.
  • Enhanced Process Between Design and Collaboration: IRONCAD COMPOSE is a free product that allows users to deliver their standard components in a lightweight and IP protected way that can be easily dragged and dropped together to automatically configure products. Often it may be necessary to make additional design changes to these configurations to meet customers’ requirements. Now users can load designs originally created by customers in COMPOSE into IRONCAD to automatically convert these to editable precise design geometry. This allows users the ability to make the desired design modifications easily on the customer configured files and quickly send the results back to the customer for validation.

In addition to these key improvements the 2014 DCS focused heavily on additional customer driven improvements and the quality and stability of the product. The 2014 DCS also includes the latest versions of ACIS™ & Parasolids™ modeling kernels, Techsoft 3D HOOPS™ Visualize Platform, and Spatial’s 3D Interop translators to provide seamless data translation with standard and native industry CAD formats.

The 2014 IronCAD Design Collaboration Suite is available for immediate download for via the IronCAD website at www.ironcad.com/download.

IronCAD
www.ironcad.com

The failed promise of parametric CAD, final chapter: A viable solution

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Model reuseWhat is the failed promise of parametric CAD? In short, model reuse.

It’s a lot more difficult than it ought to be, for a variety of reasons. Several months back, I wrote a series of articles discussing those reasons, as well as some of the solutions that have come up over the years.  What was missing from the series was a final chapter; a detailed description of what could prove to be a viable solution to problems with model reuse: the resilient modeling strategy.

The resilient modeling strategy (RMS) is the brainchild of Richard “Dick” Gebhard. I wrote about Dick last June, in the article A Resilient Modeling Strategy. He’s a low-key guy with deep experience and serious expertise in the practical use of MCAD software. Over his career in CAD, he’s been a reseller for CADKEY, Pro/E, and most recently, Solid Edge.

RMS is a best practice for creating CAD models that are stable and easily reusable (even by inexperienced users.)  It can be learned and easily used by typical CAD users, it preserves design intent in models, and provides a mechanism by which managers or checkers can quickly validate a model’s quality.

Resilient Modeling Strategy

When Dick first started thinking about the concepts that make up the resilient modeling strategy, it was natural that it was in the context of showing the advantages of Synchronous Technology (The Siemens PLM brand name for its version of direct modeling.) In our discussions about RMS over the last year or so, I pointed out that, while I thought that RMS did indeed demonstrate the benefits of hybrid history/direct modeling in Solid Edge, for it to be taken seriously, and not be unfairly dismissed as a marketing initiative for Solid Edge, it needed to work with a wide variety of MCAD tools. I think Dick got where I was coming from, because he’s continued to refine and generalize RMS, with feedback from users of a number of MCAD systems.

In its current incarnation, RMS works particularly well with Solid Edge, as might be expected, but also works very well with Creo, NX, CATIA, and IronCAD (all of which are hybrid history/direct systems.) Further, with a few modifications, it can provide compelling value with SolidWorks, Inventor, and Pro/E (all of which are primarily history-oriented systems.)

It’s significant that RMS is also free to use. While Dick is available to provide presentations, seminars, and training, he has not attempted to patent, or keep as trade secrets, the underlying concepts of RMS. (He does claim a trademark on the term “Resilient Modeling Strategy,” which means that organizations offering commercial training on RMS will need to get Dick’s OK to use the term.)

Dick has posted an introductory presentation on RMS at resilientmodeling.com. While the entire presentation is 20 minutes long, the first 3-1/2 minutes cover the problems that people invariably experience when reusing or editing history-based CAD models. Watching that much will likely convince you to watch the rest.

On Wednesday, November 20, at 10:00 AM PST, Dick will be hosting a webinar on RMS. It’s scheduled to last just 30 minutes, with the emphasis on content, not hype. If you’re a serious CAD user or a CAD manager (or, for that matter, you work for an MCAD developer), it’ll be well worth your time to attend.

TL;DR: Resilient Modeling Strategy is a best practice for creating high quality reusable 3D MCAD models. It works with many CAD systems, it’s easy to learn and use, and it’s free. Big payoff for MCAD users. 

Presentation at resilientmodeling.com

Register for Nov 20 webinar on Resilient Modeling

 

 

 

The failed promise of parametric CAD part 5: A resilient modeling strategy

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bamboo-gardenThe model brittleness problem inherent with parametric feature-based modeling is a really big deal. And it’s something, honestly, that I don’t have a great answer for. I’ve even asked a few power users who I know, and their answers seemed to involve a bit of hand-waving, and a reference to having lots of experience.

While best practices are a potentially good step forward, they need to be straightforward enough that mere mortals (as opposed to power users) can follow them.

Around Christmas last year, I got a call from Richard Gebhard, an engineer’s engineer, who has made his living selling CAD, and training people to use it (including more than his fair share of power users), for longer than he would like me to admit. (I’m pretty sure I’ve been in the CAD industry longer than him, though.) Richard told me he had something he wanted to show me, and if I’d take the time to meet him, he’d buy me lunch.

What Richard showed me was a way of creating and structuring CAD models that made a lot of sense. It not only reduced parent-child dependencies, but it made them more predictable. And, more importantly, it made it a lot easier for a mere mortals to scan through the feature tree, and see if there were any grues (it’s a technical term. Feel free to look it up.)

Over the next several months, we had lunch several times. I made suggestions. He rejected some, accepted some, and thought about others. At the same time, he was bouncing his ideas off several of his best power users (including his son). By a couple of months ago, he had refined his system to the place where it would work impressively well with nearly any parametric feature-based CAD system. So, he went to work finalizing his presentation.

I had mentioned that Delphi, by patenting some of the elements of horizontal modeling, limited the number of people who could benefit from it. (Worse for them, they patented it, then filed bankruptcy. That didn’t help much.) Richard’s goal wasn’t to monetize his process. His goal was to evangelize it. To help CAD users—both power users and mere mortals—to get their jobs done better.

Richard and I had talked, over time, about what he should call this process. At first, I liked the word “robust.” In computer science, it is the ability of a system to cope with errors during execution. In economics, it is the ability of a model to remain valid under different assumptions, parameters and initial conditions. Those are good connotations. But, then I thought of one of my favorite examples of robustness. The first time I visited Russia, I noticed that the apartment buildings were built of thick poured concrete. Very robust. And nearly impossible to remodel.

Richard’s system wasn’t robust. It was resilient. So, he has named it the Resilient Modeling Strategy. RMS.

So far, I’ve written over 2,600 words, to provide some background on the problems of parametric modeling, and some of the solutions that have been offered over the years. But, after all that, I’m not going to tell you anything more about RMS. At least, not yet.

Tomorrow, Wednesday, June 26, Richard will present RMS for the first time ever, at Solid Edge University, in Cincinnati, Ohio. His presentation will start at 9:00AM local time, and will be in room 6 of the convention center. If you’re there, put it on your calendar. If not, you’ll need to wait until Richard gets back to Phoenix, and I publish a follow-up post.

RMS is not anything difficult, or fundamentally new. It’s just an elegant distillation of best practices, designed to work with nearly any parametric CAD system, and simple enough that it doesn’t get in the way.  It’ll help you make better CAD models faster.

The failed promise of parametric CAD part 4: Going horizontal

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In the early 90s, Ron Andrews, a senior product designer at Dephi’s Saginaw Steering Systems Division, became fed-up with the difficulties of editing parametric CAD models. So, he and a team of his colleagues, including Pravin Khurana, Kevin Marseilles, and Diane Landers, took on a challenge of trying to find a solution.

They came up with an interesting concept that they called horizontal modeling. Here’s a description of it from their patent abstract:

“Disclosed is a horizontal structure method of CAD/CAM manufacturing where a base feature is provided and one or more form features added to it to form a model. The form features are added in an associative relationship with the base feature, preferable a parent child relationship, but are added in a way as to have substantially no associative relationships with each other. The result is a horizontally-structured Master Process Model where any one form feature can be altered or deleted without affecting the rest of the model. Extracts are then made of the Master Process Model to show the construction of the model feature by feature over time. These extracts are then used to generate manufacturing instructions that are used to machine a real-world part from a blank shaped like the base feature.”

Here’s a picture that makes it clearer:

Horizontal Modeling

The simplest explanation I can give for it is this: You create a base feature, and bunch of datum (working) planes. You attach all the child features to those datum planes. Viola: no parent-child problems.

I admit that I’m not going to do justice to horizontal modeling in this conversation. There’s actually quite a bit to it, and it makes a lot of sense when coupled with computer-aided process planning (CAPP.)

Horizontal modeling has a handful of problems. First, it does a pretty good job of killing the possibility of having design intent expressed in the feature tree. Next, it works better with some CAD systems than others. (When horizontal modeling was in the news, SolidWorks had a problem managing the normals on datum planes, so it didn’t work too well.) The deadliest problem is that Delphi got a bunch of patents on the process, then licensed it to some training companies. From what I can see (and I may be wrong), none of these training centers offer horizontal modeling classes any more.

While, technically, you can’t use horizontal modeling without a patent license from Delphi, the concepts at its core are fairly similar to things that CAD users have been doing for years. A few years ago, Josh Mings posted on a couple of online forums that “Horizontal Modeling is just one word for it, you may also know it as Skeleton Modeling, Tier modeling, Sketch Assembly modeling, CAD
Neutral Modeling, or Body Modeling.” (It’s actually two words for it, but I get his point.)

Horizontal modeling is not a silver bullet solution for the problems inherent in parametric feature-based CAD. It’s just a best practice—a strategy for getting around the problems. It seems to be headed in the right direction, but it suffers from the complexity that comes from trying to fix too many problems at once.

Next: A Resilient Modeling Strategy

The failed promise of parametric CAD part 3: The direct solution

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Pull-PushDirect modeling—a syncretic melding of concepts pioneered by CoCreate, Trispectives, Kubotek (and many others)–has shown the most promise to cure the parametric curse.

Direct modeling is today’s hot CAD technology. PTC, Autodesk, Siemens PLM, Dassault (CATIA, but not so much SolidWorks), IronCAD, Kubotek, Bricsys, SpaceClaim (and certainly some other companies I’ve forgotten) all have their own unique implementations of it.

The common thread in direct modeling is to use standard construction techniques when modeling, and feature inferencing (or recognition) when editing. It’s easier said than done. It’s taken about 35 years of industry research to get to the place we are today—where you can click on a face of a model, and the system will recognize that you’re pointing to a feature that has some semantic value. And that’s not even considering the tremendous amount of work that has been required by legions of PhD mathematicians to develop the math that lets you push or pull on a model face, and have the system actually edit the geometry it in a useful manner.

For the CAD software, figuring out which way to edit a selection is almost a mind reading trick: A user clicks and drags on a part of a model. What would they like to happen? In some cases it’s easy: Drag once face of a rectangular block, and the system will just make it longer or shorter. But if the block is full of holes, bosses, and blends, it becomes a lot more complicated. What should the system do if you drag a face so far back that it consumes another feature, and then pull it back to where it was? Should the consumed feature be lost forever, or should the system remember it in some way, so it can be restored?

There are no right answers. It seems that no two direct modeling systems handle the decision of what is a “sensible” edit in the same way.

While direct modeling absolutely solves the model brittleness problem inherent with parametrics, it does it by simply not using parametrics. Even with hybrid parametric/direct CAD systems, the answer to the parametric curse is still to not use parametrics when you don’t need to.

The solution of “use direct modeling when you can, and learn to live with parametric hassles when you can’t” just isn’t very satisfying to me.

Next: Going horizontal

The failed promise of parametric CAD part 2: The problem is editing

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ErasermIn the previous post, I wrote about the failed promise of parametric CAD: problems such as parent-child dependencies and unwanted feature interactions, coupled with no easy way to either prevent, or check for them.

The difference between modeling and editing in a parametric CAD system is simply the difference between creating things from scratch, and modifying things you’ve already created. The distinction may seem academic, but it is only when editing that parent-child dependencies are a potential problem.

Consider a scenario, of creating a parametric part—one that you’ve worked out in your head pretty well ahead of time—where you start from scratch, modeling sequentially, and spending all your time working on the most recent feature without needing to go back to edit upstream features.

In that context, the model’s parent-child dependencies would exist, but would be benign. They’d never get in your way. That is, until you went back to edit the part.

In most cases, people don’t build models from scratch without periodically going back to adjust earlier features from time to time. In that process, they’ll catch, and be able to deal with, some of the dependencies. But not likely all, or even most, of them.

I’ve heard experienced CAD people use an interesting term for models with hidden and untested parent-child dependencies: Parts from hell. When you’re trying to modify them, you never know when a small change might cause them to completely fall apart. I think a better, more descriptive, term is brittle: Hard, but liable to break or shatter easily.

This also suggests a descriptive term for CAD models which are not liable to break or shatter easily: resilient.

I’ve only ever seen one group of users who could consistently create complex yet resilient parametric parts models from scratch: PTC application engineers from the early to mid-1990s. Of course, they could only do it during customer benchmarks, with parts they’d practiced ahead of time, where they had worked-out and memorized all the steps, and where they had a good idea of the parameter ranges. Even then, if you were to ask them to change a dimension that would cause a topological change, the models might unceremoniously blow up.

Not to paint too bleak a picture, there are certainly CAD power users who have the skills to create resilient CAD models. I’ve met more than a few of them: true professionals, who by combining experience, insight, and education, have earned the respect of their peers. They understand how to structure CAD models to avoid any problems with brittleness.

Nah. I’m just messing with you. Power users struggle with this just like us mere mortals. It’s just that their models don’t usually fall apart until you go outside the scope of parametric changes they had anticipated. Give power user’s carefully crafted CAD model to a user who has a black thumb (I’m sure someone comes to mind), and they’ll find ways to blow it up that the power user never imagined.

Next: The direct solution

The failed promise of parametric CAD part 1: From the beginning

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The modern era of 3D CAD was born in September 1987, when Deere & Company bought the first two seats of Pro/Engineer, from the still new Parametric Technology Corporation. A couple of years later, Deere’s Jack Wiley was quoted in the Anderson Report, saying:

“Pro/ENGINEER is the best example I have seen to date of how solid modelers ought to work. The strength of the product is its mechanical features coupled with dimensional adjustability. The benefit of this combination is a much friendlier user interface plus an intelligent geometric database.”

According to Sam Geisberg, the founder of PTC:

“The goal is to create a system that would be flexible enough to encourage the engineer to easily consider a variety of designs. And the cost of making design changes ought to be as close to zero as possible. In addition, the traditional CAD/CAM software of the time unrealistically restricted low-cost changes to only the very front end of the design-engineering process.”

To say Pro/E was a success would be a terrible understatement. Within a few years PTC was winning major accounts from the old-line competitors. In 1992, on the strength of its product, PTC walked away with a 2,000 seat order from Caterpillar that Unigraphics had thought was in the bag.

The secret to Pro/E’s success was its parametric feature-based solid modeling approach to building 3D models. To companies such as Deere and Caterpillar, it offered a compelling vision. Imagine being able to build a virtual CAD model of an engine, and, by changing a few parameters, being able to alter its displacement, or even its number of cylinders. And even if that wasn’t achievable, it would be a great leap forward to just be able to rapidly create and explore design alternatives for parts and assemblies.

Yet, things were not that easy. In 1990, Steve Wolfe, one of the CAD industry’s most insightful observers, pointed out that Pro/E was incapable of making some seemingly simple parametric changes.

Pro/Engineer placed limits on the range of parameters. (A designer could not increase the dimension of L2 to point that L3 vanished.)
Pro/Engineer placed limits on the range of parameters. (A designer could not increase the dimension of L2 to point that L3 vanished.)

David Weisberg, editor of the Engineering Automation Report (and from whose book, The Engineering Design Revolution, I have liberally cribbed for this article), pointed out the fundamental problem with parametrics:

“The problem with a pure parametric design technique that is based upon regenerating the model from its history tree is that, as geometry is added, it is dependent upon geometry created earlier. This methodology has been described as a parent/child relationship, except that it can be many levels deep. If a parent level element is deleted or changed in certain ways it can have unexpected effects on child-level elements. In extreme cases (and sometimes in cases that were not particularly that extreme), the user was forced to totally recreate the model… Some people described designing with Pro/ENGINEER to be more similar to programming than to conventional engineering design.”

Weisberg barely scratches the surface of the issues that can create problems.

In 1991, Dr. Jami Shah wrote an Assessment of Features Technology, for Computer-Aided Design, a journal targeted to people doing research in the field of CAD. He identified that there were problems with features:

“There are no universally applicable methods for checking the validity of features. It is up to the person defining a feature to specify what is valid or invalid for a given feature. Typical checks that need to be done are: compatibility of parent/dependent features, limits on dimension, and inadvertent interference with other features. In a study for CAM-I, Shah et al. enumerated the following types of feature interactions:

  • interaction that makes a feature nonfunctional,
  • non-generic feature(s) obtained from two or more generic ones,
  • feature parameters rendered obsolete,
  • nonstandard topology,
  • feature deleted by subtraction of larger feature,
  • feature deleted by addition of larger feature.
  • open feature becomes closed,
  • inadvertent interactions from modifications.”

The important thing to notice here is that, not only are there multiple failure modes for features, there are also no universal methods for validating features. It’s left up to the user to figure out. And that process, as Weisberg hinted, is much too difficult.

Rebuild Error

Since the early days of Pro/E, a lot of work has been done, both by PTC and other companies in the CAD industry, to improve the reliability and usability of parametric feature-based CAD software. Yet, the problems that Weisberg and Shah identified still exist, and still get in the way of users being able to get the most from their software.

Next: The problem is editing.

 

Open Source CAD? No. Free CAD? Yes.

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If you’re looking for a really great open source CAD program, you’re going to be disappointed. Many people, individually and in groups, have tried to build quality open source CAD programs. And none have come close to succeeding. At least, at the level where they challenge the capabilities of commercial products.

CAD software is complex in a way that few other applications are. To build a commercial quality CAD system, you’re looking at a lot of work, by a lot of experienced (and expensive) software developers.

That doesn’t mean there isn’t free CAD software.

I wrote about Three Free CAD Programs for Engineers and Designers in the July issue of Design World. In the article, I talked about IronCAD Compose, Autodesk Inventor Fusion, and Siemens PLM Solid Edge 2D Drafting. Each of these programs is being made available, for free, by commercial software developers.

The companies all have their own reasons for giving away software. Ultimately, they hope to get you to buy some other software, but their path there is different.

IronCAD Compose can be used to as a tool to manage catalogs for configure-to-order products. It just happens that the best way to make the components for those catalogs is to use IronCAD (the CAD program, not the company.)

Inventor Fusion is a direct modeling CAD program. It’s a really good program. If Autodesk can get you to use it, and if you like it, you’re probably going to be interested in looking at their main Inventor CAD program—which isn’t free.

Solid Edge 2D Drafting is a wonderfully good mechanical drafting program. Siemens PLM gives it away because they’d rather have their customers spend money on their 3D CAD products than on competitors’ 2D CAD products.

Another free 2D program I didn’t mention in the magazine article, DraftSight, has that same goal. Dassault Systemes gives it away so that their 3D customers don’t need to spend money on 2D CAD software from competitors. (And, in both cases, with Siemens PLM and Dassault Systemes, the product they’re targeting is AutoCAD.)

Actually, there are quite a number of interesting free CAD programs out there. The fact that they’re not open source doesn’t make them any less useful.