Blazing new trails at Design ShowBlazing new trails at Design Show

Exhibitors at the National Design Engineering Show, an annual March mecca for designers across all industries, came to Chicago with offerings attractive to those who design with plastics. Although the show still has a heavy emphasis on mechanical design, many suppliers are keenly aware of the growing role of plastics in housings, electrical connectors, medical products, automotive applications, and other markets. As a result, software packages are changing to include optimization tools that can minimize material and maximize stiffness. RP systems are getting faster and more affordable. Moldfilling analysis software now focuses on specific functions within the design and development chain. The bottom line? Change is good.

Software Savvy

CAD developers are starting to get closer to the designer’s thinking process in creating automated tools for part and product optimization. Two contenders in this category have recently added a feature known as behavioral modeling (Parametric Technology’s version) and topological optimization (from MSC Working Knowledge) aimed at auto-mating some of the iterations required to reach the most cost-efficient, functional design.

In Pro/Engineer 2000i, behavioral modeling is a core technology integrated throughout the solid model. It lets designers specify the requirements and behavior of what they’re designing rather than just taking geometry into account. “For example,” says Wayne George, Parametric’s strategic marketing vice president, “you can keep a part’s center-of-gravity along a particular axis, make a gas tank hold 10 gallons, design headlamp covers to optimize reflection, or even produce an exhaust manifold design that meets airflow criteria.”

Once the criteria are set, the Behavioral Modeler will generate several design iterations, which can then be modified, selected, or recalculated. In the case of the gas tank, this pro-cess took 90 seconds. “We wanted to create a tool that eliminates the close-enough design estimate, substituting optimal solutions with a full understanding of performance and behavior instead,” adds George.

Other changes in PTC offerings include a designed-for-Windows user interface that offers less complexity and faster learning curves, and an associative topology bus added to i-series applications for data sharing among Pro/E modules as well as Unigraphics, Catia, and STEP files. Pricing is also modular: Pro/E-Foundation ($5995), can be coupled with the Behavioral Modeler ($3495) and other modules for Windows 95, 98, or NT platforms.

MSC has made some changes to its lineup as well, integrating recently acquired Knowledge Revolution into a new division called MSC Working Knowledge. In addition to several other programs, the company offers Working Model Concept for topology and geometry-based shape optimization. According to Dave Baszucki, vice president and general manager, this is the first product to integrate both types of shape optimization tools with Windows-based CAD systems.

To automate the iteration process, the system generates conceptual designs based on user-defined functional criteria. Users specify the range of changes allowed and the goal of optimization, click an icon, and the CAD model changes. Designers can minimize weight, for example, while maintaining a certain window of structural integrity. In addition, Concept contains automatic mesh generation for finite-element analysis. These FEA results can also be used to optimize designs. Integrated with Autodesk Mechanical Desktop, Solid Edge, and SolidWorks, the software uses the CAD system’s interface to decrease learning time. Pricing information was not available at time of publication.

Collaborative CAE

If you are a project engineer, your responsibilities may include selecting materials, determining moldability, balancing runners, and estimating cycle times, to name a few. C-Mold recently introduced a tool called Project Engineer aimed directly at supporting these and other design functions.

Using a 2-D sketcher with automated drawing capabilities, project engineers can bypass CAD models and translation issues to work on balancing and sizing runner systems, estimating cavities and costs, even minimizing part thickness. Other features include material selection using the full C-Mold materials database, moldability studies, reducing runner scrap, estimating production cycle times, and calculating material consumption.

When completed, the Project Engineer file can then be sent to C-Mold’s 3D QuickFill or Advanced Solutions for traditional CAE analysis. The 2-D sketch is not translated; rather, the data generated is applied to the 3-D solid model created by the part designer. The Windows-native package sells for $2499, and can be used before, during, and after CAD model development to improve collaboration between project engineers and other disciplines.

3-D Printing

Imagine the day when you’ll be able to download replacement parts, toys, and other plastic items from the Internet, then “print” them out in 3-D. That version of desktop manufacturing is one step closer to reality, according to 3D Systems. To replace its Actua 2100, the company has introduced a faster and less expensive 3-D printer called ThermoJet Solid Object Printer ($49,995 for single units). It uses a multiple-jet printhead that is four times larger and 31/2 times faster to achieve 300-by-400 dpi resolution.

Mervyn Rudgely, director of product management, explains, “We are targeting two build times —an 8-hour shift, and a 14-hour overnight build. Almost any part can be built in these time frames.” Besides speed, the new system supplies a higher-heat, wax-based polymer (rated at a 90C melting point) with added toughness for better stability.

The printer hooks up to ordinary office networks and accepts STL files sent from the designer’s CAD system. It can also be used as a 3-D fax when files are sent via Internet to printers anywhere in the world.

“Being able to hold a sample of a new design in your hands within hours greatly improves communication and can help pinpoint flaws,” adds Rudgely, “especially for multinational design efforts.”

Data Exchange

John McEleney, marketing vice president for SolidWorks, believes that part file translation is one of the biggest issues facing designers. “We found that many of our customers who need 3-D capabilities also have AutoCAD and Mechanical Desktop. They want to leverage the solid model by importing it into AutoCAD. In the past, this meant exporting data in a neutral file format.”

To make life simpler, SolidWorks is offering a free plug-in called Xchangeworks, which is available on the company’s website (www.xchangeworks.com). It lets users import part files directly from SolidWorks, Pro/E, and Unigraphics into AutoCAD using the ARX interface. You can get a copy of this plug-in via the website or by calling (800) 393-4118.

Traditionally, data sharing hasn’t been a strong point for most software vendors. But SolidWorks made the effort to support its customers, according to McEleney. “We’re committed to making designers more productive and efficient by making their jobs easier,” he says. “Data sharing is a fact of life today, so we are working within that reality.”