Military helicopters are designed to fly in extreme environments. So the engineers behind chopper design must ensure that their aircraft can perform under the most adverse conditions, which can make for time-consuming design.

Now propulsion engineers at Sikorsky Aircraft of Stratford, Conn., have cut the time it takes to run airflow and other CFD simulations after bringing in a computer cluster to speed their work. The new cluster runs simulations for the CH-53K cargo and personnel helicopter that Sikorsky is helping to build for the U.S. Marine Corps.

The Marine Corps plans to replace its Super Stallion heavy-lift helicopter with the CH-53K. The helicopter now under design must be able to carry a cargo load of 27,000 pounds for up to 110 nautical miles at an altitude of 3,000 feet, said Mike Kaz- lauskas, propulsion engineer for the CH-53K program at Sikorsky.

Also, the helicopter will fly in temperatures that can easily top 90°F. Weather like that can quickly erode a helicopter's capability to carry cargo for long distances. The extreme flying conditions make aerodynamic design particularly crucial, Kazlauskas said.

On earlier projects, his team borrowed time on the Linux computer systems assigned to other Sikorsky departments. Team members scheduled computational fluid dynamics studies whenever time was available, Kazlauskas said. But tight deadlines and larger data sets prompted the recent purchase of the Altix XE system from SGI of Sunnyvale, Calif. Now the team spends less time waiting and more time working, he said.

Another benefit of the dedicated computer cluster: Models that once required up to four days to be completed are now finished in a few hours.

"Previously, we had models that were 3 million cells in size. But today, some models have more than 12 million cells," Kazlauskas said. "We're running larger, full-vehicle simulations that include complex interactions, like rotor-downwash effects and heat-transfer models. We needed access to more memory and more processors."

The team is currently focusing on propulsion by studying design elements that affect capacity and cargo load, like gas reingestion and engine-bay cooling. The engineers next will turn their attention to airflow through the entire helicopter.

You can draw a straight line on your computer with relative ease. But software engineers spent a long time learning how to program computers to draw objects as basic as a spoon.

The challenge is a mathematical one, said Tony DeRose, senior scientist and head of the research group at Pixar Animation Studios in Emeryville, Calif. The computer graphics programs that can draw spoons and faces are the result of complex mathematical calculations. Those programs have culminated in the studio's work on films like The Incredibles and, more recently, Ratatouille.

DeRose spoke about the relevance of math at Math Fest earlier this year at the University of California, Davis. The event is meant to bolster math's image in an era that sees a limited supply of graduates with employable math skills, according to Jesus De Loera, an organizer of Math Fest and a math professor at Davis.

You are what you eat: In the movie Ratatouille, a rat named Remy dreams of becoming a great French chef. Remy is created from mathematical calculations done on a computer. So is the cheese.

The Sacramento Bee, a newspaper in Sacramento, Calif., covered Math Fest activities and spoke with De Loera.

Of the 30 percent of college entrants who plan a major in science and engineering, fewer than half complete a degree in the disciplines, according to the National Academy of Sciences.

Recruiting DeRose, one of the gurus behind Pixar's computer graphics wizardry, is one way to show how exciting math can be, De Loera said.

So what kind of math goes into computer graphics? Trigonometry describes rotations and movement in three dimensions. The final picture that appears on screen comes from solving a series of linked equations with many unknowns, called simultaneous equations. Calculus is the foundation of programs that simulate water and clothing, DeRose said.

For instance, the skin on Pixar's characters is, to a computer, an elaborate surface that forms in complicated ways. New math, born some 25 years ago, provides algorithms that efficiently describe such curves and surfaces.

All Pixar movies, except the first Toy Story in 1995, used this new math called subdivision surfaces, DeRose said. Before the new math, animators would dice a complex surface like a character's face into tiny fragments that were easier for a computer to represent. Then they had to stitch the pieces together in a smooth way so that the seams were invisible. Subdivision surfaces math makes the process much easier by getting rid of the seams entirely. This allows animators to make complicated surfaces, like clothing and skin, more realistic, DeRose said.

Imagine a mechanical Pelé or a David Beckham one-sixth the size of an amoeba kicking a soccer ball no wider than a human hair across a field that could fit on a grain of rice.

That was pretty much the scenario when the National Institute of Standards and Technology in Gaithersburg, Md., held its first nanoscale soccer games during the July 2007 RoboCup in Atlanta.

The nanosoccer competition pitted the smallest RoboCup robots against each other in order to show off the tiny technologies used to fabricate MEMS, according to a NIST spokesman. Although the soccer-playing robots range in size from a few tens to a few hundred micrometers long, they're considered nanoscale because mass ranges from a few nanograms to a few hundred nanograms.

A chip 2.5 mm on a side holds 16 playing fields for teams in a nanoscale soccer league.

The soccer-playing nanobots needed to be fast, agile, and capable of manipulating objects.

These abilities were tested in three events: a two-millimeter dash in which each nanobot competed for the best time in a sprint across the playing field; a slalom drill where the path between goals was blocked by defenders—in this case, polymer posts; and a ball-handling drill that requires robots to dribble as many nanoballs—or microdisks—as possible into the goal, according to a NIST spokesman.

The nanoscale soccer players competed under an optical microscope. Coaches controlled the players via remote electronics that relied on visual feedback. Observers viewed the games on a monitor.

Five teams competed in the Nanogram Demonstration Competition—two from Carnegie Mellon University in Pittsburgh and one each from the U.S. Naval Academy in Annapolis, Md.; the Swiss Federal Institute of Technology in Zurich, and Simon Fraser University of Burnaby, British Columbia.

The Swiss team swept the competition. It took first place in the two-millimeter dash, at 316 milliseconds; first in the slalom, at 583 milliseconds, and first in the handling drill, with three goals.

This year's competition was held as a demonstration event with plans for it to become the Nanogram League in 2008, according to NIST.

An automotive supplier with plants on four continents is in the process of introducing Design for Manufacture and Assembly software to all its locations worldwide as part of its value management program. The supplier, TRW Automotive, has more than 100 plants in North and South America, Europe, and Asia. It has five business units that manufacture engineering fastener products, and systems for braking, steering, body control, and occupant safety.

The software, generally known as DFMA, is from Boothroyd Dewhurst Inc. in Wakefield, R.I. It is intended to guide engineers in designing products that will be efficient and economical to make. The software explores the properties of parts, and choices of materials and manufacturing processes.

According to the developer, as much as 70 percent of a product's lifecycle cost is determined in design. Simpler designs with fewer parts require fewer assembly steps, and so reduce the chance for error. Fewer parts can also reduce costs not only of labor and assembly but also of materials, inventory, sourcing, and other overheads. One of the original intents of the company's founders, Geoffrey Boothroyd and Peter Dewhurst, in developing the software was to design products for automated assembly.

A user of the software enters information on the parts of an assembly one at a time, identifying them not only by dimensions, but by other properties, including assembly method and estimated difficulty, and why each part needs to be separate. For instance, the user tells the software that a part must be separate because it is a base part, must be of a special material, must move, or must be separate for assembly purposes. The software also estimates the costs of labor, material, and tooling to make parts and to assemble the finished product.

According to James Bolton, a corporate value management specialist at TRW Automotive, the company wants to standardize the use of the software in all its business units.

Bolton said that the company has developed a three-day workshop designed to be used for training employees at each of the company's sites around the world. The program includes specific blocks of time scheduled for discussions and workshops to assure that the training—and, therefore, the understanding of the software—is as uniform as possible throughout the company.

He said the rollout and training are in progress, so TRW has no estimate at this point of what it will yield in savings when the software is fully adopted.

In a presentation this summer at the Boothroyd Dewhurst users' forum, Bolton discussed a cost breakdown for a rack and ball nut subassembly that compared three versions of the product.

One was a design from a competitor. Another was a current in-house design by TRW, and the third was a new TRW design that would make use of a new manufacturing process. By using DFMA software, the company was able to work out costs for manufacturing and assembling the products. The total cost worked out for the competitor's subassembly came in 7.5 percent below TRW's. The proposed TRW product, using the new manufacturing process, was lowest of the three— almost 8 percent cheaper to make than the competitor's product.

According to Bolton, the software was able to document the improvement, and the information helped open some business opportunities with a major automaker. Bolton said TRW is working toward a target cost for electric power steering systems requested by the customer.

MSC.Software of Santa Ana, Calif., which sells simulation software, has acquired pioneerSolutions Inc. of Northville, Mich. The acquisition allows MSC.Software to offer a simulation platform that includes fluid, structural, thermal, acoustic, motion, and mechatronic analysis capabilities. PioneerSolutions' software automates virtual testing.

Finite element analysis vendor Algor Inc. of Pittsburgh has opened an office in Stanley, N.C., about 17 miles northwest of Charlotte, N.C. The office will offer sales and services to the Carolinas and Georgia.

Capvidia of Leuven, Belgium, is shipping its bidirectional STEP translator. The translator was developed to meet the requirements for data translation, model quality checking, CAD validation, and long-term archiving, said a company spokesperson. This new STEP translator is available in all Capvidia products or as a set of libraries to integrate into third-party applications.

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