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With today’s product development practices, it is rare that one company completely designs every component. More often, companies selectively work with outside resources—trusted suppliers or design consultants—that may not use the same design applications they do. Or even more commonly, the CAD system used to manufacture a component is different from the one used to design it. Any Pro/ENGINEER® user who has faced these situations knows that overcoming the resulting interoperability problems can take a tremendous amount of time, effort, and money.
But new approaches are now available that allow engineers to share feature-based Pro/ENGINEER models with design teams working with “foreign” CAD applications. These solutions—available either as a stand-alone software product or as an outsourced service—enable collaborative development of new designs, with fully parametric models, while design teams continue to use the applications in which they are most proficient.
The following scenario illustrates how an OEM might use one such solution, the Proficiency Collaboration Gateway™, to move the main design forward in Pro/ENGINEER while collaborating with a supplier using a different CAD application. Since the Collaboration Gateway allows both users to read and modify models at the feature level, they quickly converge on an optimal product design.
Let’s say the OEM produces small stereo speaker systems, of the type used with a consumer-class PC. A key supplier—the maker of the speaker cone itself—has recently added a new product to its line. To update the speaker assembly as quickly as possible (and beat his competitors to market), the OEM asks the component maker to contribute his design expertise to the project. The obstacle, however, is that the OEM works in Pro/ENGINEER while the supplier has standardized on Unigraphics™.
Initial design from the OEM. Since the project is an update to an existing design, the OEM uses the original design of the enclosure cover as the starting point (Fig. 1).
Fig. 1. Initial parametric part design in Pro/ENGINEER.
In the past, the OEM might have used STEP (Standard for the Exchange of Product Model Data) or IGES (Initial Graphics Exchange Specification) to provide the supplier the external shape as the starting point for the design effort. In addition, the OEM would have manually created and distributed any necessary data sets, either on physical media or via FTP. This generally requires that the supplier remodel the “dumb geometry” into his own system. Using the available surface information, the supplier would “best-guess” the intended feature content. All this “preprocessing” would have had to occur before any useful design work could begin.
Feature-based CAD model interoperability solutions, in contrast, eliminate the error-prone and time-consuming process of collecting and delivering data sets. The user need not worry about which STEP API to use or which IGES entity will best map to the receiving system. For companies managing their CAD data with PDM applications like Pro/INTRALINK, APIs are available to integrate programmatic data exchange. The user simply selects the source CAD format and the target CAD format (Fig. 2). A featured parametric model is then delivered to any location accessible over the network.
Fig. 2. Browser-based Collaboration Gateway user interface.
In this example, the OEM uses simple pull-down menus in a web browser interface to exchange the assembly model from Pro/ENGINEER 2001 to Unigraphics v18. (This product also supports I-DEAS® 9 and CATIA® v4 and v5. Support for Pro/ENGINEER Wildfire is expected by the end of 2003.) The OEM also chooses to have the software notify both him and his supplier via e-mail upon completion of the exchanges, and to receive detailed reports showing the operations carried out and results achieved. After submitting the job, he is now free to address other tasks.
The Collaboration Gateway then delivers the supplier a featured Unigraphics native part file (Fig. 3). The model includes features, history, constraints, dimensions, parameters, metadata, and other attributes from the Pro/ENGINEER model. The supplier can immediately begin to make design modifications such as adding or removing features, reordering, and dimensional or constraint changes. In fact, all of the familiar modeling functionality available in Unigraphics is at his disposal.
Fig. 3. Parametric cover in Unigraphics.
Feature-based modifications by the supplier. The supplier must now “design in” a new speaker. To accommodate the change, he adds new parametric features. He also notices that the enclosure wall is too thin to accommodate the planned injection molding process. He simply increases the “shell” thickness and the part is complete—including all the feature-based enclosure changes (Fig. 4).
Fig. 4. New speaker added to the subassembly in Unigraphics.
With his component design complete, the supplier now uses the Collaboration Gateway to return the parametric data for the new subassembly—including all of the parts, assembly instance locations, and product structure—to the OEM in a Pro/ENGINEER format.
Completing the design. From this point, the OEM can use the supplier’s parametric subassembly to complete his design in Pro/ENGINEER (Fig. 5). The OEM thus interacts with all of the design components—both his own and those received from the supplier—just as he normally would, since they are all native Pro/ENGINEER parts and assemblies. He does not have to worry about re-mastering or guess about the feature content or parameter values. He can easily see the increased shell thickness introduced in Unigraphics and then match the wall thickness of the other components to this parameter.
Fig. 5. Top-level assembly completed in Pro/ENGINEER.
If quality assurance is an important step in the manufacturing process, why shouldn’t it be in the product development process? Design partners must be sure the CAD data they are giving and receiving is accurate and meets the recipient’s requirements. Furthermore, documentation of the data exchange is critical in proving liability claims should the program encounter problems or delays.
The Collaboration Gateway creates a detailed set of reports for each data exchange task. These reports let users not only see task results at a summary level, but also the details of how an exchange was carried out on a feature-by-feature basis. Furthermore, the Collaboration Gateway calculates and compares a part’s physical properties (such as mass, volume, and moments of inertia) in both the “source” and “target” CAD systems at the part or feature level. Users can therefore be certain the design was transferred accurately and precisely, with no undesired changes introduced along the way.
In this age of collaborative engineering, Pro/ENGINEER users are increasingly likely to find themselves co-designing with users of different CAD systems. The incompatibility of CAD data formats can make this a frustrating, time-consuming and expensive process. While existing solutions such as IGES and STEP have certainly provided benefits, they do not satisfy the most demanding user requirements—the exchange of parameterized models across disparate platforms.
A new generation of feature-based CAD interoperability solutions promises to lower the productivity barriers that extended design teams face today. By enabling more efficient collaboration, these solutions significantly reduce development costs as well as time to market. 
Ken Klapproth is director of product marketing at Proficiency, Inc. in Marlborough, Massachusetts, USA. Proficiency has been a PTC/USER industry Partner since May 2002 and will be available at the 2003 World Event in Orlando. He can be reached by e-mail at KenK@proficiency.com.
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