By 2005, plants won't be able to operate without first testing production runs by means of digital factory software, according to Emmerich Schiller, who is director of digital production planning in the passenger car division at DaimlerChrysler in Stuttgart, Germany.

Schiller spoke at the Delmia user group meeting held recently in Stuttgart. Delmia makes digital factory software.

"On the assumption that, in the long run, only five or six car manufacturers and about 1,000 suppliers will be left by 2005, the crucial thing is to speed up production with fewer model ranges and more model variants," Schiller said.

Planners today spend more than 70 percent of their time collecting, testing, and updating data, he said. In the future, those planners might be able to access the current state of the actual factory digitally—that is, to see a digital, working mockup that mirrors current factory workings. Planners could access the data from anywhere they happen to be, said Gunter Schmidgall of the automaker's research and development arm.

All factory data could be monitored continually, he added.

Maj. Steve Schweitzer, who teaches a computer-aided design course at the U.S. Military Academy in West Point, N.Y., thinks that professors should devote the most time possible in the classroom to content, and students should spend less time learning how to use support technologies.

For example, the more time professors spend explaining the ins and outs of finite element analysis programs, the less time students will have to spend learning the theories and principles of engineering design and analysis, Schweitzer said.

Schweitzer said he uses an FEA software package called Cosmos/DesignStar from Structural Research and Analysis Corp. of Los Angeles. He said that students are able to pro-
duce meaningful analyses after just a few lessons.

The globe set within the newly completed Al-Faisaliah Tower in Riyadh, Saudi Arabia, was created and mounted in the building with the help of design software.

Engineers used CAD software from TekCAD of Longwood, Fla., to design the 79-foot golden globe on the Al-Faisaliah Tower in Riyadh, Saudi Arabia.

The owner of the multi-use, 875-foot skyscraper decided to change the original design significantly while the building was still under construction. The owner, Prince Bander, wanted a globe mounted partway up the building. The building's contractor, Turner International, brought in StarNet International Corp. of Longwood, Fla., specially for the globe. The company designs, engineers, and fabricates domes, spaceframes, and climatic envelopes.

StarNet used CAD software called TekCAD from TekStar of Longwood, Fla., to develop and link the triangular faces that make up the 79-foot golden globe.

StarNet then worked with the consulting design team Buro Happold Engineers of Bath, England, to create a floating globe effect based on the CAD configuration.

Before assembling the globe, StarNet engineers used a model-building system that was included in the CAD software to make a one-meter prototype of the globe. With that prototype in hand, engineers were more easily able to determine how to install the globe 584 feet high on the building.

To help test a new design, the John Deere Golf and Turf division turned recently to a consulting firm tied to its technology supplier. John Deere had redesigned a ball joint lift yoke on its line of lightweight fairway mowers with the hope of improving the mowers' cutting performance, and grass-catching ability.

Engineers in the division wanted to make sure the product would work as designed. To that end, they worked with engineers at Manta Corp., who field-tested and analyzed the design.

In order to measure performance of the new design, the Manta engineers collected data on how the mower performed on a variety of terrains. They also carried out finite element analysis of the assembly to predict stresses for unit load. Then, they combined the measured data with the stress results and simulated a variety of scenarios to predict the useful life of the new design. For this, they used software from International TechneGroup Inc. of Milford, Ohio, where Manta is also located. Manta is a majority-owned subsidiary of ITI.

With the test results in hand, John Deere engineers determined that the new design would meet the company's requirements.

Coin Acceptors Inc., a St. Louis maker of coin mechanisms, bill acceptors, and control systems for food and beverage vending machines, has found a way around one of its engineering challenges: the molding of plastic parts that require close tolerances.

"Typically, coin changers are restricted in size and require small and accurate components," said Max Molenaar, senior engineer at the company. He supervises the tool design and drafting departments as well as the model shop and prototyping and computer-aided engineering activities at the company.

Coin Acceptors of St. Louis uses plastic-flow-analysis software from Moldflow of Wayland, Mass., to design small parts for its vending-machine coin and bill acceptors.

Coin Acceptors engineers began using plastics simulation software called Moldflow Plastics Insight from Moldflow of Wayland, Mass., in September of last year.

Now, Coin Acceptors' engineers use the software to analyze each newly designed plastic part. That analysis lets engineers plan and position the cooling lines before machining them, which helps prevent the need for retooling, Molenaar said.

The engineering team is also using the plastics software to design new parts—some as large as 6 inches wide by 18 inches long and others, including small gear pieces, with quarter-inch diameters.

Molenaar determined that, before implementing the plastics simulation software, he and his colleagues spent about eight hours per model to generate meshes and clean them up. With the new software, Molenaar says he has saved around 120 hours of labor on mesh generation. He calculates that the company will save more than $26,000 per year as a result of the reduction in labor.

Visual-ization for Quieter Vehicles

Researchers in Pennsylvania State University's aerospace engineering department are using parallel computers, virtual reality systems, and visualization software to test the causes of aircraft noise and to find ways to reduce it.

While engines cause the majority of noise from aircraft, aerodynamic noise is also a contributor. This noise comes from atmospheric wakes, turbulent airflow passing the fuselage and wings of the airplane, and a phenomenon called flow separation. In this phenomenon, an uneven airflow causes drag, loss of lift, and increased noise and vibration.

Penn State researchers have been focusing their attention on the effects of this flow separation on helicopters, but research in that area could lead to improvements in many types of vehicles, said Lyle Long, a Penn State professor of aerospace engineering involved in the studies.

"Separated flow is very common in airplanes, automobiles, helicopters, trucks, trains, and water vehicles," Long said. "Being able to predict these flow fields would have an enormous impact on designing better vehicles. They could potentially be more efficient and also quieter."

The airflow around a complex body such as a helicopter always leads to flow separation, which causes increased drag and noise, Long said. Helicopters also generate a downwash of air from the rotor blades that can cause additional flow separation on the fuselage, leading to unusual aerodynamic loads and more noise, he said.

If designers could predict separated flow in helicopters, they could design quieter, more efficient helicopters.

To better understand separated flow, Long recently tested the Parallel Unstructured Maritime Aerodynamics code for generating time-accurate flow data. The goal was to use the code to help predict helicopter airframe noise coming from complex parts, such as landing gear, slats, and flaps. For the tests, the research team used parallel computers, a virtual-reality environment called a reconfigurable advanced visualization environment, or RAVE, from Fakespace Systems of Kitchener, Ontario, and visualization software called Ensight Gold, from Computational Engineering International of Apex, N.C., which worked with the RAVE.

The RAVE is made up of 8-foot-square panels that fully surround the researcher. The Ensight Gold software displays animations and also automatically detects and displays flow features, such as shock waves, cortex cores, boundary layer separation, and reattachment lines.

"Visualization is crucial to evaluating these codes," Long said. "Our simulations are really four-dimensional—space and time—so traditional graphics are inadequate. Many of our simulations can't be understood or interpreted by just looking at a computer monitor."

Long said that with the technologies' help, he and his team are closer to understanding flow separation, which will eventually lead to vehicles that emit less aerodynamic noise.

Researchers in California have created a publicly available database of acoustic measurements of human subjects.

Richard Duda and V. Ralph Algazi, who are researchers at the University of California, Davis, said the database could have a wide range of applications, including teleconferencing, mobile computing, and home entertainment.

"One day, computer users could operate a small, wearable computer using voice commands, with spatial sounds replacing a visual display," Algazi said. Also, the database could help develop a virtual-reality system that would allow engineers and scientists to inter-act with their data in a 3-D space that uses images and sound.

People use a number of complex sound cues to experience their surroundings, Algazi said. However, reproducing those cues accurately is a difficult technical problem. The cues that stem from the interaction between sound waves and the human body are important, but they are difficult to reproduce.

Among the challenges to creating 3-D sound fields is that each person's spatial sound cues are influenced by individual factors, such as the shape and position of the person's ears, Algazi said. These factors vary greatly among individuals. To mass-produce digital systems that accurately reproduce 3-D sound fields, engineers need information about each listener's spatial sound cues. The new database provides the information that engineers need to design these fields.

To develop the system, Duda and Algazi measured 45 different people to see exactly how the sizes and shapes of their ears and bodies influenced the sounds they heard. Acoustic measurements were stored in a database, together with measurements of the size and shape of the listeners' ears, heads, and torsos.

By knowing how a click pattern gets changed on the way to a listener's ears, an engineer can modify any sound presented over headphones to make it seem as if it is coming from a particular location in space. Because people have individual sizes and shapes, the modification must be individually tailored, much as eyeglasses are individually fitted, Algazi said.

Lacking data, engineers previously have had to base their designs on an average set of values, which resulted, for listeners, in sounds analogous to vision through a poorly fitted set of eyeglasses. The database should provide engineers with the information to properly adjust their designs to account for individual differences, according to Duda.

The database may help engineers build personalized sound systems for computers that could rival or exceed the experiences of listening to a high-end home stereo system, according to the National Science Foundation in Arlington, Va., which funded the work.

The information may be downloaded via the Internet.

Gibbs and Associates of Moorpark, Calif., developer of computer-aided manufacturing software, is now shipping GibbsCAM 2002.

EDS of Plano, Texas, has released Unigraphics Quick Stack, a software program that is part of what the developer calls its Product Lifecycle Management Solutions line of business.

The provider of simulation software and services MSC.Software of Los Angeles has released MSC.Fatigue 2001, which predicts the durability of structural components and assemblies.

Ricoh Corp. of West Caldwell, N.J., has released the Aficio 470W, a digital wide-format copier that is upgradeable to a high-resolution scanning and printing digital imaging system for CAD designs.

The maker of computational fluid dynamics software Fluent Inc. of Lebanon, N.H., has released Gambit 2.0, a general-purpose preprocessor for CFD analysis.

Allsheets, Inc. of Orlando, Fla., a manufacturer of CAD software and AutoDesk developer, has released its Detail Compiler software. It is for CAD professionals who use cut symbols and detail drawings and is an Autodesk add-on. The software automatically compiles details on the existing drawing or a separate one.

PlanetCAD Inc. of Boulder, Colo., has released its first commercially available version of SCS|Envoy, which is software that streamlines the handling, security, and transmission of manufacturing data.

Cimatron Technologies of Livonia, Mich., has released Cimatron E, Windows-based CAD/CAM software designed for the tooling industry.

ESI Group of Detroit, a provider of virtual prototyping and manufacturing solutions, has released Pam-Opt, a software package intended to speed virtual prototyping time.

A maker of engineering design software, Vistagy Inc. of Waltham, Mass., will release new versions of its FiberSim and EnCapta design software at the National Design Engineering Show in Chicago March 18-21.

Inovx Solutions of Irvine, Calif., has released version 2.3 of the company's RealityLinx and 3-D PlantLinx software.

The enterprise software maker Oracle, of Redwood City, Calif., has released Oracle CADView-3D. The software allows users with a Web browser to par-ticipate in collaborative design of 3-D CAD model creation or review over the Web.

SolidWorks Corp. of Concord, Mass., has released an upgrade to its 3-D PartStream.net service, which lets component manufacturers publish 3-D Web-based catalogs using a step-by-step process.

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