ICAD interoperability problems started as soon as the second CAD system became available. And although that was decades ago, the problem still persists today.

While neutral translators such as IGES and STEP have improved, they still have a way to go because models run through these formats usually need some sort of fixing up. So-called “native translations,” available for most CAD systems, have other problems: during conversions, all those parametric features that were so carefully placed on the model and enable the user to make easy edits are lost and can’t be modified.

While some users don’t need to see (or don’t want to share) features, most would agree that the inability of CAD systems to exchange this information is currently the biggest obstacle to collaborative engineering. At the same time, most users have also been convinced that fundamental differences in the programming of CAD software, as well as the complexity of the models to be translated, make feature-based translations impossible.

The time has come to change this thinking. New technology has emerged that eliminates the longstanding problems of cross-system interoperability. In fact, many companies are already taking advantage of this new capability to reduce cost and speed time to market.

Take the case of Sikorsky Aircraft Corporation, the leading manufacturer of helicopters for over 60 years. The company’s latest project, the RAH-66 Comanche, is billed as the world’s most advanced helicopter (Fig. 1). How else could one describe a machine that can fly sideways or backwards at 70 mph? Creating a device like this has its own design, engineering, scheduling, budgeting and manufacturing challenges. Sikorsky did not want file translation problems to be an issue as well.

Like most companies producing mass quantities of complex products, Sikorsky needed to subcontract a lot of the work to outside suppliers. Williams International, world leader in the development and manufacture of small gas turbine engines, won the contract to design an advanced Subsystem Propulsion Unit (SPU) for the new Comanche.

While the pairing of these two industry giants seemed like a perfect match, their use of different CAD systems was an immediate obstacle. Sikorsky engineers use CATIA, while Williams engineers use Pro/ENGINEER. In typical cases the solution would be for Williams to switch to CATIA for the duration of the project. This approach would not only make the task an expensive and time-consuming ordeal for Williams, but also impact the engineers who wouldn’t be working in the system of their choice—potentially affecting the quality of work.

Another typical solution would be to deal with featureless geometry by working with direct translators and with IGES or STEP files. This option creates the need for engineers to spend an enormous amount of time healing and rebuilding models. This manual process also introduces errors, many of which go undetected until the manufacturing stage, which is a very costly problem.

These traditional approaches were unacceptable to Sikorsky and Williams. They instead opted for a third solution— feature-based translations. The results were far better than imagined (Figs. 2 and 3). By the end of the project, Sikorsky estimated if it had remodeled the SPU that Williams designed, the costs would have been twice as high. The helicopter maker also figured that the technology cut months off the job, reducing the design cycle by some 75%.

Figure 2. Pro/ENGINEER® part designed at Williams International.

Figure 3. Converted part in Sikorsky's CATIA system. Notice how it includes a complete feature tree.

With the confidence feature-based native translations actually work, Sikorsky and companies with similar challenges now have new freedom to pick suppliers not by the CAD system they happen to use, but rather by their ability to do the job at hand.

Translation Technologies, Inc., a privately owned company based in Spokane, WA, provides software technology that streamlines the design-to-manufacturing process by enabling OEM and supplied companies to share complex models fully and accurately across CAD systems. TTI offers feature-based native translations to and from the four major systems, Pro/ENGINEER®, CATIA, SDRC I-DEAS®, and Unigraphics. For more information about the company and its service, visit www.translationtech.com.