Engineers at Purdue University in West Lafayette, Ind., have designed a system they say can detect flaws hidden inside the composite materials of military missiles.

The missiles can be damaged if they're struck by the debris that a helicopter's rotors kick up or if they're mishandled during shipping or maintenance. But more so than metals, composites can conceal telltale signs of damage, according to Douglas Adams, a Purdue associate professor of mechanical engineering.

However, missiles made of composite materials are in demand more and more because casings can weigh as much as 40 percent less than those made from aluminum alloys. The lower weight makes them less expensive to ship and easier to handle.

The new monitoring system that Adams helped develop relies on a mathematical model to pinpoint the location and severity of impacts to the composite material.

The researchers used a 15-foot-tall tower that rammed a steel rod into the casing with enough force to punch holes in military armor. A sensor called a triaxial accelerometer collected the vibration data that stemmed from the steel-rod ram.

The mathematical models then interpret sensor data to determine within seconds whether an impact is beyond the design threshold, Adams said.

His monitoring system focuses on the missile casing, a 7-inch-wide, 30-inch-long segment located between the rocket motor and warhead.

"The casing is essentially a cylinder that holds the solid rocket fuel and it has to withstand the high pressures created as the fuel burns," Adams said.

These casings are made out of car- bon fibers, Kevlar, or other materials wound in layers, he added.

The team has shown that 98 percent of the time the system can detect, locate, and quantify the force of impacts, Adams said.

In addition to detecting damage caused by an accident, the researchers want to gather data to help engineers design more impact-resistant casings in the future.

For instance, research shows that some casing and missile designs are more prone to damage because the force of impact concentrates in a small area.

"You want a material that distributes that impact load along many fibers so that no one fiber is carrying too much load, which could cause it to break," Adams said.

In addition, the same monitoring technique could one day be applied to commercial aircraft and spacecraft, as well as to bridges and railways, Adams said.

How do civilians act after the detonation of an improvised explosive device? How can a commander react to calm bystanders and defend against further asttacks?

To find the best answers, Science Applications International Corp. will soon be running these types of virtual scenarios in its new laboratory on the University of Nebraska campus in Omaha. The opening of the labora- tory was reported in a story in the Omaha World-Herald.

The laboratory is part of the Peter Kiewit Institute at the university. It includes a supercomputer that can help a defense contractor get answers to complex battlefield questions faster than it ever could before.

Science Applications International of San Diego has several large government contracts in Iraq. Its new laboratory uses video and computer equipment to run what can sometimes look like video games but are actually complex predictors of military behavior, action, and reaction, said Beverly Seay, Science Applications' senior vice president.

One day, lab simulations could be used to virtually show troops the weather and terrain they will face when they go into combat, Seay said. Or, it could run war games, in which the computer predicts how the enemy will react to a particular air strike or a ground attack while researchers watch the action on large video screens.

One electronics manufacturer has reduced the time spent developing its radio frequency identification labels from about 10 days to three. It cut down the development time by modeling the labels with electromagnetic simulation software before producing them.

Sentronik GmbH of Witzhave, Germany, supplies RFID labels for a range of manufacturing, distribution, and retail applications, said Georg Siegel, Sentronik's CEO.

The RFID-label design provides a challenge for engineers. The material to which the tags are attached, the tags' orientation, and their operating frequency all play a role in performance.

When they use traditional, physical experiments, engineers have a hard time studying performance factors because of the sheer number of design parameters they need to examine. In the past, Sentronik engineers relied upon calculations with spreadsheets and math calculation programs. But the calculations could only be rough approximations because they didn't take into account the geometry of the labels and environment, Siegel said.

The company recently began using Flomerics' MicroStripes electromagnetic simulation software to carry out the simulation.

"Simulation greatly improves the design process by enabling our engineers to evaluate the performance of many possible designs without having to build physical prototypes," Siegel said.

The software is from Flomerics of Surrey, England.

The engineer stares intently at a virtual dashboard. He's testing a new driver-assistance system that can play text messages aloud and warn drivers of potential collisions in a heavy fog.

Systems like that aren't too far away. They're currently in development by automakers around the world. Now the Fraunhofer Institute for Industrial Engineering in Stuttgart, Germany, has created software specifically designed to help the engineers who design these driver-assistance systems.

The Fraunhofer software creates virtual prototypes of the systems so engineers can test and tweak them.

"The user is seated in a virtual driving simulator, surrounded by a virtual world, facing a virtual dashboard with a virtual control system," said project manager Manfred Dangelmaier. "This allows the engineers to simulate every conceivable situation in order to test the man-machine interfaces.

"Whatever demands the driver may make, such as retrieving up-to-date traffic jam warnings, can be tested," he added.

Standard-issue wheelchairs don't need to be standard. Engineers at Entz Aerodyne have applied what they've learned when creating parts for business jets to creating a new style of wheelchair.

When an economic downturn had affected Entz of Valley Center, Kan., company president Keith Entz and two partners began looking outside the aviation industry for something they could manufacture.

Engineers applied techniques for aerospace design to a wheelchair that weighs 18 pounds.

They formed Aero Innovative Research Inc. to apply aerospace-industry experience to wheelchair design. Entz and his partners said they designed and built their Flight Ultralight wheelchair using the same materials and principles that Entz Aerodyne uses to make thrust reverser panels and wire harnesses for business jets.

"Wheelchairs had been made pretty much the same way for the past 70 years. They're like patio furniture, with bent and welded tubing and fabric," said Matt Cochran, AIR's production manager. "We saw wheelchairs as screaming for new technology."

Engineering techniques carried over from aerospace design to wheelchair design. For instance, engineers perform FEA simulation on the Flight Ultralight to make it as lightweight and compact as possible. They also carry out stress analysis on its custom-manufactured components, Cochran said.

For simulation, Aero engineers used FEA software from Algor of Pittsburgh. The finite element analysis helped engineers identify and reduce stress points and optimize the strength and weight of parts.

"We asked, where can we remove material? We then cut out everything that was unnecessary," Cochran said. The resulting Flight wheelchair—designed in about a year—weighs 18 pounds and measures just over nine inches from rim to rim when folded.

Sports equipment designers will soon be able to call upon a new simulation model that demonstrates how potential products, like a new ball, will behave in real life.

The simulation shows exactly what will happen when a ball has a specified amount of force or spin applied to it, and how it will bounce and roll on a specific surface.

The model, being developed by researchers at the Sports Technology Research Group at Loughborough University in Leicestershire, England, will help sports equipment manufacturers make equipment for specific user needs, said Andy Harland, who leads the research group.

"There's plenty of anecdotal evidence that children and some adults are deterred from taking part in sport because of ill-fitting or badly designed equipment," Harland said. "It's ironic that a largely sedentary activity like developing computer models can make a real contribution to the quality of sporting performance."

The model includes Abaqus FEA software from Simulia of Providence, R.I. The Loughborough team adds algorithms to the FEA software so it can simulate the characteristics of a particular piece of sports equipment and of different playing surfaces, Harland said.

ITI TranscenData of Milford, Ohio, has upgraded its data interoperability tool to CADfix version 7.1.

Altair Engineering Inc. of Troy, Mich., is shipping HyperCrash/Catia, which is crash-modeling software integrated with Catia version five from Dassault Systèmes.

ICAM Technologies Corp. of Montreal has released Virtual Machine version 17, the upgrade to the developer's machine tool simulation and numerically controlled post-processing software.

The company formerly known as Cyco Software, now renamed BlueCielo ECM Solutions of Rijswijk, The Netherlands, has released InnoCielo Publisher 2007 and InnoCielo Publisher Framework 2007. These are upgrades to the developer's add-ons to its enterprise content management software, InnoCielo Meridian Enterprise, which automates the rendering and publishing of engineering content.

Noran Engineering Inc. of Westminster, Calif., has upgraded its simulation product, NEiFusion, to version 1.2. The new version contains two new tools for use at the CAD stage, Automated Impact Analysis Wizard and Optimization Analysis.

FreeDesign Inc. of Longmont, Calif., has released FreeDimension 1.2, a freeform 3-D surface modeler.

CAD Schroer Group of Moers, Germany, is shipping version 3.0 of its Medusa4 Design Automation Suite. l A spokesperson for Seemage Inc. of Newton, Mass., said the 4.2.1 release of its software is now compatible with SolidWorks 3-D CAD software. This allows the CAD software's users to create animations, technical illustrations, and service procedures.

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