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Articles from 1997 In November


Standards update

Standards update

New power rule could require
massive redesign of products

A new standard under consideration would set limits for power harmonics emitted by all types of electrical equipment into the public power grid. A European-dominated subcommittee of the International Electrotechnical Commission (IEC) drafted the guideline, IEC 1000-3-2. The Information Technology Industry Council strongly opposes it. Nearly all information-technology equipment uses modern, switched-mode power supplies that produce power harmonics. Meeting "unnecessary" limits proposed by the standard would require redesign of a vast array of products, complains Council President Rhett Dawson. "For the IT industry sector alone, this redesign will cost over $1 billion a year," he adds. Although IEC standards are voluntary, many countries routinely convert them into import-hampering regulations. Dawson maintains that the public power system of North America readily accommodates harmonics produced by modern electrical equipment.


Europe and North America reduce duplicate testing of goods

Duplicate certification procedures for products have long hobbled trade between North America and Europe. At long last, some progress is being made in erasing such barriers. It's seen in a Memorandum of Understanding reached between America's Underwriters Laboratories Inc. and Laboratoire Centraldes Industries Electriques, a product testing and certification organization headquartered in France. Under the agreement, a manufacturer may put the American UL mark, the Canadian C-UL mark, or the European NF mark on a product that has received the approval of either laboratory. The agreement initially covers only electrical equipment for information technology, laboratory, test and measurement, and medical uses. In another development, the U.S. and the European Union concluded a Mutual Recognition Agreement covering six export sectors. It provides for the mutual recognition of inspection, testing, and certification standards of medical devices, pharmaceuticals, pleasure boats, telecommunications, electromagnetic compatibility, and electrical safety.


Internet abounds with sites for standards community

The World Wide Web has become a major tool for those who must keep abreast of the complex, fast-changing realm of standards. The American National Standards Institute has added NSSN Enhanced to its NSSN Basic site. The new service provides detailed standards information, including abstracts and a list of equivalent standards. You can get details, as well as subscription rates, through the free NSSN Basic at www.nssn.org. The Standards Engineering Society, meanwhile, has established a home page at www.ses-standards.org. It includes links to standards developers and engineers, information specialists, and librarians. WebDEX of the Society of Automotive Engineers (SAE) now carries what the society claims is a complete collection of current and canceled aerospace and ground-vehicle standards and aerospace materials specifications. WebDEX also has an index to SAE's archives and current listings of engineering and design resources. To subscribe, click on www.sae.org/WEBDEX. There is also a new source for information on international standards for environmental management at www.iso14000.net/.


Interface guideline simplifies mixing of sensors, actuators

A new standard promises to simplify the complex task of interfacing "smart" transducers into the more than 50 different types of proprietary networks deployed throughout industry. Smart transducers are combinations of digital sensors and actuators. The standard adopted by the Institute of Electrical and Electronics Engineers is IEEE-1451.2. Representatives of NIST and 25 firms developed it. Network-independent, the new digital interface provides a common bridge for reading sensors, setting actuators, and accessing key identifying and historical information on the devices. It could bring "plug and play" into control networks that monitor and adjust manufacturing.


Accreditation changes proposed for Fastener Quality Act

NIST seeks public comments to changes it proposes in the Fastener Quality Act, a national program to ensure that certain nuts, bolts, and other fasteners conform to specifications. One change would allow accreditation of manufacturing facilities that use quality assurance systems, such as QS-9000, for statistical control during processing. The regulation, due for implementation next May 26, currently requires that testing and approval for each lot of fasteners come at the end of the production line and only by an accredited testing laboratory. The auto industry has contended that online quality testing is much more effective than lot sampling and should be recognized under the act. An accredited testing laboratory still would conduct end-of-line testing, which is typically invoked to confirm the in-process statistical control system.

Technology bulletin

Technology bulletin

Everybody was kung fu fighting, virtually

Fighting arcade games are all the rage, but using a joystick can diminish the joy of beating the tar out of someone. Sony Corp., Tokyo, Japan, and Holoplex, Pasadena, CA, have teamed up to replace traditional input devices for video games with an optical gesture recognition system. Two players face each other (out of arm's reach) on a strip flanked on one side by a blue screen. A CCD camera is focused on each participant. Player motion is captured, the image data are sent to an optical box, where they are converted to laser light and projected onto an LCD. A detector array picks up the refracted laser light and the data are processed to recognize the player's gesture. This gesture becomes the input for the corresponding virtual fighter in the video game. In practice, a pantomime punch throne by a player is copied by his or her avatar. Likewise a kick. Duck down and the video fighter ducks also. Start a little jump and the character leaps into the air like Jackie Chan. A prototype of the system was on display at the SIGGRAPH 97 computer graphics show in Los Angeles last August. This writer, ignorant in the martial arts, relied on fencing moves to strike fear and pain into his opponents, retiring undefeated but extremely sweaty. For more information, contact Fai Mok, president of Holoplex at (818) 793-9616.


Evidence appears before their eyes

Researchers at Sandia National Lab, Albuquerque, NM, are developing a portable evidence detection system to take the Colombo our of sleuthing. Investigators using the system would wear a vision-enhancement system derived from a set of 3-D video game goggles to locate trace evidence at crime scenes, such as fingerprints, semen, urine, and other organic substances. Sandia's evidence detection technology relies on the fact that all organic substances emit weak fluorescent light, normally invisible to the unaided eye. A lamp on the system's headset flashes 100 times per second. Shutters on the goggles open and close at a slightly different frequency. About twice a second, the shutters open when the lamp is off, and this seems to make fluorescent materials "flash." The Albuquerque Police Department's crime lab hopes to test a prototype sometime in 1998. For more information, contact Dave Sandison, Sandia, at (505) 844-9644.


NASA searching for a solid solution

Single-stage-to-orbit vehicles and high-flying, suborbital aircraft may one day employ scramjet engines to propel them into the upper regions of the atmosphere. In order to solve fuel mixing problems in these power plants, NASA's Marshall Space Flight Center is examining how solid hydrogen fuel might provide the necessary distribution properties for scramjet combustion. Thoughtventions Unlimited, Glastonbury, CT, developed the concept wherein a pellet of solid hydrogen is injected into the supersonic airstream of a scramjet combustor. NASA modeled a solid hydrogen particle ablating in a Mach 3 airstream to better understand the physics of the problem and predict parameters such as particle lifetime. So far, studies have indicated that a solid hydrogen pellet injected into a combustion chamber with a little liquid helium would provide superior fuel distribution and mixing while eliminating injector drag. Additional studies may determine the feasibility of the technology for large scramjet engines. For more information, contact Stephen Bates, president, Thoughtventions Unlimited, at (860) 657-9014.


Getting ready for the Big One

Conventional wisdom and modern science agree: It's just a matter of time. Therefore, the Pacific Earthquake Engineering Research (PEER) Center is investigating ways to mitigate casualties and property damage from major earthquakes in urban areas. PEER is one of three new centers funded by the National Science Foundation dedicated to earthquake research and will be headquartered at the University of California-Berkeley. PEER's focus will be on how hazards can be reduced in large urban areas and will pool talent from the disciplines of seismology, engineering, political science, and economics. Other universities participating in the center are the four other University of California campuses, Stanford, Cal Tech, and the University of Washington. The other new centers for earthquake research will be headquartered at the University of Illinois-Urbana and the State University of New York-Buffalo. For more information, contact Helmut Krawinkler, professor of civil engineering, Stanford, at (650) 723-4129.


U.S and Mexican labs sign test exchange agreement

Product certification specialist Underwriters Laboratories (UL), Northbrook, IL, signed a test-data exchange agreement with the Asociacion Nacional de Normalizacion y Certification del Sector Electro (ANCE) and Camara Nacional de la Industria Electronica y de Communicaciones Electricas (CANIECE), its Mexican equivalents. Under the terms of the agreement, UL , ANCE, and CANIECE will exchange appropriate test data for clients seeking product certification in both Mexico and the United States. Once test results have been reviewed by each lab, the manufacturer is eligible to apply for UL certification in the U.S. and NOM certification in Mexico. "We are working to make global product certification a one-step process for manufacturers," says Bob Harris, vice president for external affairs at UL. "Our cooperative efforts with Mexico will make it even easier for telecommunications and electronics manufacturers to access both U.S. and Mexican markets through one submittal process." Product categories covered under the agreement are telecommunications and electrical business equipment. For more information, contact Traci Maloney, UL, at (847) 272-8800 x43436.


Climate prediction delves into the past

While the weather rock remains the only sure-fire way to gauge the weather (when it's wet it's raining, etc.) researchers at the University of Wisconsin-Madison believe ancient history may help tune large-scale computer models to make them more accurate. Neolithic North Africa was a well-watered grassland with many shallow lakes. By understanding those forces that have transformed it into the desert it is today, scientists hope to make better predictions about the future. According to researchers John Kutzbach and Zhengyu Liu, the tropical Atlantic monsoons strongly influence the climate in this region. "The northernmost reach of the monsoon marks the limit of vegetation," notes Kutzbach, a paleoclimatoligist. "There is a nice boundary where vegetation stops and the sand begins." According to Kutzbach, monsoons were stronger six thousand years ago because the Earth's orbit was slightly different then than it is now and the Northern Hemisphere was closer to the sun during summer. Monsoons are driven by contrasts between the temperatures in the ocean and the land and used to be much stronger. As a result, the moisture-laden tropical air of the tropical Atlantic penetrated deeper into North Africa. By calculating how atmosphere, vegetation, and ocean interact, Kutzbach hopes to incorporate these interactions in computer climate models. For more information, contact John Kutzbach at (608) 262-2839.


WE ARE HERE!!!DNA coding on a budget and a deadline

A new DNA sequencing technology developed by GeneTrace Systems Inc., Menlo Park, CA, promises to provide results hundreds of times faster than current systems and at a fraction of the cost. The process combines DNA probing, sequencing, and sizing reactions with laser-based mass spectrometry. The system identifies the sequence of DNA base chemicals in five seconds rather than the three hours required for gel-based DNA separation methods. In addition, GeneTrace expects the technology to permit screening tests that cost a few dollars rather than the $500 to $3,000 they cost today. Robotic systems handle initial samples. New methods and reagents were formulated to support the automated process. The company developed software to make accurate distinctions among the various subunits of DNA. In all, eight patents are pending relating to the rapid sequencing technology. Research was co-funded by the Advanced Technology Program of NIST. For more information, contact Christopher Becker at (415) 859-3718.


Death of a star

The new Near Infrared Camera and Multi-Object Spectrometer aboard the refurbished Hubble Space Telescope have enabled scientists at MIT's Center for Space Research to pull back the shroud of the Egg Nebula, revealing a dying star. Now, stars die all the time, sometimes with a bang, sometimes with a whimper. What makes this particular star so striking is that it is very much like our own sun, so the image perhaps is a view of the fate of the solar system, several billion years hence. The dying star, located in the constellation Cygnus, is 3,000 light years distant. MIT researcher Joel Kastner says the most interesting aspect of the phenomenon is the cloud of gas and dust being expelled by the star as it burns out. "Studying the death of such stars is important for understanding how two elements crucial for human life--carbon and nitrogen--are introduced to the interstellar medium," Kastner says. "Eventually, these elements become the building blocks of new stars and planets." The Near-Infrared Camera has proven especially valuable in the observations. For more information, contact Elizabeth Thomson, MIT Research Digest, at (617) 258-5402.


Turning fuel into noise

The U.S. Air Force is working with major automobile suppliers to improve the sound quality of automotive exhaust systems. The Armstrong Lab at Wright-Patterson AFB, Ohio, will develop tools for evaluating the acoustic impact of such systems. The Air Force will use them to study aircraft noise, while Arvin Industries Inc., Columbus, IN, will use the same technology to develop similar tools to analyze car noise. The acoustic analysis systems will quantify human perception of sound quality. Currently, fine-tuning of exhaust systems is accomplished using the trained ears of sound quality evaluators. The evaluators will be used to verify the computer models developed for the automated systems. The project is part of a multi-phase effort; eventually researchers hope to determine whether computer-based models can be used to evaluate human annoyance. For more information, contact Bobbie Mixon, office of public affairs at Wright-Patterson's Aeronatical Systems Center, at (937) 255-2725.

Las Vegas' fluid power

Las Vegas' fluid power

Las Vegas--As Rodney Dangerfield might say, they're a tough crowd. Spoiled by the best acts in show business, frazzled by hours at the gaming tables, visitors to Las Vegas want the finest entertainment that winnings can buy.

Yet, they are here, lining the Forum Shops at Caesars Palace, waiting to see an eight-minute show without a single human performer. Granted, they are skeptical: They wander through the rotunda, where the show is staged, studying the aquariums, the marble statues, the flowing fountains, and they scratch their heads.

The Show
Animatronic figures and statues rise from a basement during the show, which is why designers needed extra-long hydraulic actuators.

But when the show starts, their doubts disappear. The statues drop from sight, replaced by animatronic figures that unexpectedly rise out of the fountain. Surrounded by a show of fire and steam, these performers argue with one another; they talk to the audience; they threaten, gesticulate, bend, turn. On closer examination, they seem almost human. Their eyes blink, their eyebrows move, their cheeks expand and contract when they speak. One figure leans wearily on his staff and slowly draws himself up from his chair. At the show's climax, the chair itself becomes an animatronic, transformed into a winged beast as the audience gasps in amazement.

"I stood next to people at the grand opening, and all I saw were jaws dropping,'' recalls Bob Crean, vice president of operations for Advanced Animations, Stockbridge, VT, the company that designed the figures.

Indeed, by the end of the show, many of the visitors also seem to have been transformed. As the show ends, even the most jaded in the audience find themselves applauding. There is, however, good reason for their applause: The "Atlantis'' show, which tells the story of the fall of the mythical lost continent, is a technical extravaganza. In addition to the animatronics, it employs stunning sound and video. Atop the dome of the rotunda, a giant god, whose face is at least two stories high, watches over the assembly and talks to the figures.

Behind the scenes, it's even more impressive. Miles of steel pipe and copper tubing supply the fire and steam for the show. Hydraulic cylinders to raise and lower the figures are as long as 35 feet. Custom-designed electronics and programmable logic controllers provide control for the lights, audio, fire, projection screens, and hydraulics.

Gadrius: Man of Many Motions
The 8-ft. Gadrius makes 45 different kinds of moves: 28 hydraulic; 17 pneumatic.

For an eight-minute show, "Atlantis'' incorporates as much technology as any of the best rides at Disney or Universal. "We've rolled all the best special effects we could think of into a single show,'' notes Larry Lester of Lester Creative, Valencia, CA, creator of "Atlantis.''

Heavy lifting required. The show takes place in a classical rotunda, adjoining Caesars Palace's Forum Shops, which opened in late August. It tells the story of the struggle for power between Atlas' children, Alia and Gadrius, and the ultimate effect it has on Atlantis.

Lester, who managed the project for the Simon DeBartolo Group, was well qualified for the job, having previously served as vice president of show technical services for Universal Studios in Hollywood. There, he was responsible for Earthquake: The Big One, and King Kong, among others.

On "Atlantis,'' Lester's team decided to endow the show with the best special effects available, which is why, by some estimates, it cost between $15-$17 million. Part of that cost is in the show's setting: A fountain, waterfall, and giant 40,000-gallon, horseshoe-shaped salt water aquarium dominate the rotunda.

But the show itself, which runs once an hour, is what draws the crowds. It begins when the five "marble'' statues (they're really made of fiberglass) suddenly retract, and are replaced by the four animatronic characters. Much of the action takes place in the center of the horseshoe, where Atlas emerges from amid the fountain. At the same time, electric motors roll murals out of the way to make room for 18 large screens, which project images on the dome of the rotunda.

The show's animatronic figures are lifted into place by dedicated hydraulic cylinders. The figures, together with their hydraulic manifolds and turntables, weigh approximately 2,000 pounds each. Lifting these massive loads required 12-inch diameter cylinders operating at 1,500 psi. The telescoping cylinders, designed and built by The Marmac Co., Xenia, OH, have a 35'-4" stroke length. The 35-foot stroke is needed to lift the figures from the basement beneath the exhibit to an area high above it (see diagram). Because the cylinders are subjected to the fountain's water, The Marmac Company also applied a stainless steel coating to the cylinders to prevent corrosion.

To retract the statues, Lester uses a hydraulic cylinder-and-winch combination. The cylinder-and-winch enables one hydraulic cylinder to move two statues. By configuring the system in this way, he estimates that he saved as much as $200,000. The reason: He eliminated the need for two extra-long (35-foot stroke) actuators.

Lester also used hydraulic actuators to lift lighted crystals into the show area. In all, he says, he employed ten large hydraulic actuators to move the statues, animatronic figures, and crystals. Four 60 HP Vickers Integrated Motor Pumps supply the power for the hydraulic systems.

The design team never considered electrics for those tasks, for reasons of cost, complexity, and safety. "We're in a very wet area,'' Lester explains. "Electric motors for this application would need brakes and other extra equipment. Hydraulics is by far the best choice for a job like this.''

Complex control. Because the show employs so many different systems--animatronics, water, fire, hydraulic lifts--control is complex. For that reason, "Atlantis'' employs a master show controller that works in conjunction with other, specialized controllers for the animatronics and water effects.

The show's master controller, known as the Synthesis system, was designed and built by engineers at Triad Productions, Inc., Des Moines, IA. Synthesis employs two Hewlett-Packard Vectra PCs, intelligent card frames, an Allen-Bradley SLC-504 programmable logic controller, scanner, power supplies and operator interface. The system works in conjunction with a servo controller built by HR Textron/Micro-Precision, Berne, IN. The servo controller oversees all moves made by the animatronics. On a lower control level, dedicated Allen-Bradley SLC-504 PLCs oversee the hydraulic lifts, hydraulic pumps, and fire effects.

The main reason for the complex control system is that each physical move in the show must be carefully synchronized with both sound and video. Engineers orchestrate the control for the show by overlaying SMPTE (Society of Motion Picture and Television Engineers) time code onto each frame of the video. As a result, the video frames store information for every light, sound, and physical movement. It then synchronizes those moves so that the figures are in the right place at the right time. If, for example, a figure's arm is inappropriately extended as it is lowered off stage, it could strike the side of the work envelope and be damaged.

"These are very, very complex figures,''notes Bill Synhorst, vice president of Triad, as well as a software and hardware developer for Synthesis. "To be sure that the show works right, we have to know where the figures are at all times.'' That means that the system must store every move made by each character at intervals of 33 milliseconds, Synhorst says.

Realistic motion. Given the sheer number of possible moves for each character, such control becomes a formidable task. The character known as Gadrius, for example, has 45 separate moving parts. Engineers at Advanced Animations, Stockbridge, VT, designers of the figures, say that no character in the show is capable of less than 25 moves.

To make matters even more complex, these motions can be hydraulic or pneumatic, analog or digital. Gadrius makes nine distinct pneumatic moves, mostly in his face and fingers, some of required custom-designed cylinders. Gadrius' fingers, for example, use tiny pneumatic cylinders made by Fabco-Air, Gainesville, FL. The cylinders have a diameter and stroke length of just a half-inch. Other pneumatic cylinders for the figures are made by SMC Pneumatics, Indianapolis, IN.

The animatronics' larger muscle moves are actuated by hydraulics. Such motions as torso forebend and body sidebend employ hydraulic cylinders from OilDyne Division of Commercial Intertech, Minneapolis, MN. Rotary actuators from Parker Hannifin Corp., Cleveland, OH, are responsible for bicep rotations.

The quantity and quality of the moves is a key to the realism of the show, say engineers. Advanced Animations achieved that realism by designing so-called "hydraulic compliance'' into its systems. Hydraulic compliance is critical for animatronic figures because it enables them to manage the inertia caused by quick acceleration. In the past, that inertia was responsible for an animatronic phenomenon known as "boing.'' In "boing,'' a figure's movement stops suddenly, causing it to vibrate. In a typical scenario, a figure may bend from the waist, then shake furiously as it reaches the actuator's end-of-stroke. While "boing'' is more acceptable on a so-called "dark ride,'' in which low visibility hampers the view of the figures, engineers have worked hard for decades to find a cost effective way to eliminate the problem.

"Everybody in animatronics wants their figures to look human,'' says Bob Crean, vice president of operations for Advanced Animations. "But humans move fast, and it's sometimes difficult for animatronics to handle that kind of fast movement. The biggest challenge is to move fast, then quickly come to a dead stop.''

By incorporating hydraulic compliance, Advanced Animations engineers say they can solve the "boing'' problem. They accomplish it by employing dual-loop PID servo control. To provide force feedback, they place load cells from Entran Devices, Inc., Fairfield, NJ, between the cylinder's body and rod end. Force and position data are gathered in separate channels in a servo card. Using a proprietary combination of hardware and software in the servo card, the system processes force and position feedback signals, then responds with commands to dampen potential vibration.

In digital pneumatics, Advanced Animations uses a system called Advanced Inertial Management (AIM) to achieve compliance. Key to AIM is a small, custom-molded bumper made from Texin(R), a thermoplastic polyurethane made by Bayer Corp.'s Polymers Division, Pittsburgh, PA. By placing the Texin(R) bumper at each end of the stroke, engineers can program quicker robotic movements without the associated vibration, Crean says. "When a cylinder reaches the end of its stroke, it's going to bang,'' he says. "That's where you need compliance.''

Crean says that compliance can be costly and complex. For that reason, he says, it's best applied only to those situations where it's absolutely necessary.

On "Atlantis,'' Crean believes that the quantity and quality of the moves has taken animatronics to a new level. "We can safely say that these are the most sophisticated animatronics anywhere,'' he says.

The animatronics, together with the sound, video, and special effects, is thus far having the desired effect. "Atlantis" officially opened in August along with The Forum Shops, to an extravaganza that included blaring trumpets, indoor fireworks, and CNN coverage. "It's only an eight-minute show,'' he says. "But it's knocking the socks off the audiences.''

SIMULINK 2.0 with MATLAB 5.0

SIMULINK 2.0 with MATLAB 5.0

Both MATLAB 5.0 and SIMULINK 2.0, its dynamic system simulator, are marked as major upgrades with new "look and feel" interfaces. It is expected that you are familiar with MATLAB's syntax structure and environment before you use SIMULINK.

SIMULINK appears as an icon on MATLAB's menu system, with the Workspace Browser. The Browser is a static display of all variables and arrays in MATLAB's workspace. Unlike in the Mac version, you can't do much with the Browser other than view and clean the workspace.

Once SIMULINK is loaded, a new window with the block diagram libraries appears. To start building your model, drag the diagrams into the workspace. The block building process is very simple and intuitive. You can cut, paste, copy sections of the model, create groups of blocks to perform a certain task, or change the screen attributes of any entity of the model. But although the block connections are easy to construct and modify, SIMULINK lacks a tool that can detect intersecting lines with different origins and destinations and either reroute them or make them distinguishable.

You can control the complexity of your model by creating submodels for parts of the system that perform a certain task. Two new powerful functions of subsystems are introduced in SIMULINK 2. A Conditionally Executable Subsystem lets you control the execution of an event while certain conditions are met. You can also have a trigger event controlling the execution of a specific subsystem.

You can start a simulation from within SIMULINK or from MATLAB's Command line. Monitors can send information to a file or display it on-the-fly. The graphical part of these monitors, called Scope, addresses the basic graphical output during the simulation, leaving the more complex plotting to MATLAB's graphics routines. Although Scope has many enhancements for setting controls, it still needs a built-in printer option. Currently you must use MATLAB's graphics commands to capture the Scope data for plotting and printing.

You can attach monitors anywhere to watch the simulation's progress. Monitors can plot single variables or, after multiplexing the blocks, you can show in a single plot the variation of several locations in the model. The Scope can float on screen, acting as a monitor of any point in the model.

You start a simulation by specifying the simulation parameters. While the simulation is running, you can open the blocks of your model, change the variables or integration algorithm, and view the results on the model's monitors.

The interface functionality of your models can increase with MATLAB's graphical user interface (GUI) capabilities. The GUI lets you add special effects such as pop-up menus. You can also animate simple physical systems with building blocks. The GUI, animation tools, or other MATLAB commands can be automatically executed in a transparent interface.

The simulations are normally running in the "interpreted mode," which implies relatively slow response and execution. SIMULINK's Accelerator option allows you to create and compile C code for your models, which will drastically increase the speed of the simulation process. The Accelerator functions in a transparent mode and, once invoked, will recompile and link the modified model. A glitch in printing prevents SIMULINK models from printing when the model extents exceed the paper size. The alternative is to use the clipboard to copy in Metafile or Bitmap format for use with other Windows applications.

Mathworks tried to integrate the two packages and eliminate redundancies in tasks and functionality. SIMULINK represents a value on its own as a system builder, complete with a GUI and enhanced tools for any level of complexity. The graphical output capabilities are not fully integrated without some customization by the user. The GUI builder and its nice tools could help in this situation with some ready-to-use templates.


Spec Box: SIMULINK 2.0 with MATLAB 5.0

SIMULINK provides the tools for modeling and analysis of any dynamic system represented as a block diagram. The Windows 95 or NT version requires an 80486 or Pentium with at least 8 to 12M bytes of RAM, 50M bytes of free disk space.

List Price: $3,700

The MathWorks, Inc.,
24 Prime Park Way,
Natick, MA 01760
ph: (508) 647-7000
www.mathworks.com

A similar product: VisSim
Visual Solutions,
487 Groton Rd.,
Westford, MA 01886
ph: (508) 392-0100
e-mail: info@vissol.com

Product News

Product News

Rod Seal

Zurcon(R) L-Cup(R) rod seal for hydraulic cylinders offers optimized pressure distribution, back-pumping ability, and better extrusion resistance. The seal is produced through injection molding in a proprietary polyurethane, Zurcon(R) Z04, with hardness shore A 93. The seal can be installed in sealing systems with double-acting scrapers or in tandem arrangements with the Turcon(R) Stepseal(R) K.
Busak+Shamban, Jupiterstraat 106, 2132 HE Hoofddorp, The Netherlands, FAX +31 23 5615225.

Gasket

Single-piece silicon rubber sealing gasket is for keyless-entry control in sport vehicles. Molded using three different color materials, the gasket provides watertight seals for the two PCB-mounted pushbutton control switches, color-codes these switches for easy identification, and provides a transparent window for viewing the battery status LED. APM Hexseal Corp., 44 Honeck St., Englewood, NJ 07631, FAX (201) 569-4106.

Belts/drive tapes

Metal belts and drive tapes have high strength-to-weight ratios, require no lubrication, operate in clean-room and hostile environments, and are thermally and electrically conductive. The products are accurate and repeatable for timing applications, are quiet, and made to customer specifications.
Belt Technologies Inc., Box 468, Agawam, MA 01001, FAX (413) 789-2786; Belt Technologies Europe, Suite 3L, Durham Mountjoy Research Centre, Stockton Rd., Durham City DH1 3UR, England, FAX +44 0191-383-1820.

Stack lights

Stack lights can be reconfigured without tools in any combination of one to six light assemblies or with an alarm or strobe. The stack lights use CAD engineering to maximize luminosity and combine impact-resistant polymers, non-corrosive support posts, rubber O-ring seals, and heat-resistant housing. Changing a light bulb or the color of a lens requires a twist of the stack light.
Cutler-Hammer, 4201 North 27th St., Milwaukee, WI 53216, FAX (412) 449-7319.

Sensor

PicoDotTM Class II convergent photoelectric laser sensor features a precise convergent point size of 0.25 mm at its focal distance, making the sensor suitable for applications such as semiconductor wafer mapping, miniature parts detection, and connector pin counting. Measuring 40 3 45 3 12.7 mm, the unit is suitable for use on robotic end effectors.
Banner Engineering Corp., Box 9414, Minneapolis, MN 55440, FAX (612) 544-3213; Banner Engineering Corp. (UK), Suite SF1, Heybridge Centre, 110 The Causeway, Heybridge, Maldon, Essex CM9 4ND, England, FAX +44 1621 841566.

Circuit breakers

M-Series line of miniature magnetic circuit breakers allows users to specify smaller-sized circuit breakers for protection, where ratings up to 25A are required. Baton and paddle actuator styles are available, and are supplied in a gloss finish in colors including red, green, blue, yellow, orange, white, and black. The series can be used to protect applications including generators, computers, and peripherals.
Carlingswitch, 60 Johnson Ave., Plainville, CT 06062, FAX (860) 793-9231; Carlingswitch Ltd., 4 Airport Business Park, Exeter Airport, Clyst Honiton, Exeter, Devon EX5 2UL, England, FAX +44 392 364477.

Motor kits

Frameless motor kits integrated into an application feature high torque to inertia ratios, speeds to 20,000 rpm, and power ratings up to 5 hp. Eight different brushless motor kits eliminate coupling, alignment problems, and backlash. Skewed stators for minimized cogging, designed with rotors with IDs of 7.6 to 139.7 mm, accommodate a range of shaft diameters for applications requiring hollow shafts.
MFM Technology Inc., 200 13th Ave., Ronkonkoma, NY 11779, FAX (516) 467-5176.

Rollnut assemblies

Guided miniature rollnut assemblies control the accuracy of actuators in critical mechanisms and are for applications requiring exact and repeatable positioning and location, such as diagnostic equipment and laboratory instruments. The guided miniature rollnut consists of a miniature rollnut screw and nut assembly modified to include a linear bearing and guide rod supported by the same end plates that secure the rollnut screw. The resultant anti-rotational device does not require an outside guide system and ensures accurate positioning.
Norco Inc., Flennor Div., 139 Ethan Allen Hwy., Ridgefield, CT 06877, FAX (203) 544-7121; Flennor GmbH, Schwarzer WEG 100-106, D-40593, Dusseldorf, Germany, FAX +37 021170077302.

Bearing material

BB-16 is a self-lubricating powdered metal bearing material used for heavily loaded applications. This bearing material features compressive strength and wearability, and is shock resistant. Applications include automotive, railroad, escalator, machine-tool, off-highway, and heavy equipment.
Bunting Bearings Corp., Box 729, Holland, OH 43528, FAX (419) 866-0653.

Motors

The Z26000 Series of high-volume 26-mm-diameter linear stepper motors for global applications use ball bearings and a rare-earth magnet. The motor provides a solution for linear-movement requirements for applications such as office equipment, medical devices, small machinery, and instrumentation.
Haydon Switch & Instrument Inc., 1500 Meriden Rd., Waterbury, CT 06705, FAX (203) 756-8724; Haydon Switch and Instrument, Isoldenstraabe 22, 80804 Munchen, Germany.

Adhesive

EP31 adhesive is for high-performance applications and features lap shear strength exceeding 4,500 psi. EP31 has high bond strength to similar and dissimilar substrates, and bonds have resistance to chemicals and a service operating temperature range of -100 to 250F. The adhesive cures readily at room temperature or more quickly at elevated temperatures, and has a convenient 3:1 mix ratio by weight. EP31 is available in 1/2-pint, pint, quart, gallon, and 5-gallon kits and syringe applicators.
Master Bond Inc., 154 Hobart St., Hackensack, NJ 07601, FAX (201) 343-2132.

Cylinder

EF1 pneumatic cylinder is a compact, aluminum-extruded body cylinder for international machine requirements. The cylinder has a PTFE-impregnated, hard-anodized aluminum body for wear resistance. The cylinder also features a miniature switch that slides into a track in the cylinder body. Expected service life of the cylinder is 2,500 km. Models are available in double-acting; single- or double-rod end; and single-acting, spring-retract, or extend.
Bimba Mfg. Co., Box 68, Monee, IL 60449, FAX (708) 534-5767; Bimba Ltd., 23 Maxwell Rd., Woodston, Peterborough, Cambridgeshire PE2 7JD, England, FAX +44 01733 391080.

Couplings

Couplings are machined from a single piece of material into specific configurations that incorporate special design features or characteristics. The couplings use a curved-beam ("flexure") design concept that transmits torque while compensating for lateral, axial, and angular misalignment movements. The curved beam enables customer-specified end attachments to be integrated into a single machined component.
Helical Products Co. Inc., Box 1089, Santa Maria, CA 93456, FAX (805) 928-2369; Helical Products Co. Inc., c/o G.J. Bohnenstiel GmbH, Postfach 101469, D-69004, Heidelberg, Germany, FAX +49 6221313250.

Heat exchangers

Model 727 liquid-to-air copper fin-and-tube heat exchangers measure 24 3 24 3 2.6 inches and are capable of dissipating 330W for every one degree Celsius difference between water and air entering the heat exchanger. A lightweight and durable aluminum fan shroud for mounting four fans is available. Applications include closed-loop liquid cooling required in cooling semiconductor manufacturing, processing, and test equipment, as well as cooling of lasers, electronic cabinets, industrial furnaces and ovens, and other demanding applications.
Thermatron Engineering Inc., 687 Lowell St., Methuen, MA 01844, FAX (508) 687-2477.

Recirculating chillers

RC006A recirculating chillers with full-PID adaptive control are for applications where tight temperature control is required. The RC006AG01 and RC006AH01 models achieve plus or minus 0.1C temperature stability and provide up to 600W of cooling in a 14 3 14 3 22-inch cabinet. The active components are mechanically isolated to minimize noise and vibration. The -G01 model is for North American electrical requirements and the -H01 is for international electrical requirements.
Lytron Inc., 55 Dragon Ct., Woburn, MA 01801, FAX (617) 935-4529.

Pulleys

Timing belts are available in an assortment of matching pulleys, clamps, tensioners, and slider beds. Standard and self-tracking pulleys are offered in both English and metric pitch as well as flat idlers. Pulley sizes are available up to a maximum width of 180 mm and maximum diameter of 640 mm. The pulleys are available in aluminum for standard requirements, steel for high-torque applications and abrasive environments, stainless steel for high-torque applications that cannot tolerate rust, and Delrin/Nylon for applications requiring light weight and rust-free operation.
BRECOflex Co., L.L.C., Box 829, Eatontown, NJ 07724, FAX (732) 542-6725.

Motor

Dc servomotor is for high-speed processing applications where precision accuracy is an important factor. High-speed capability offers increased system throughput to reduce machine cycle times. The three-phase design is compatible with industry-standard servo amplifiers and servo controllers. Standard NEMA packaging in size 23 and 34 permit drop-in replacement of motors into existing stepping-motor-based systems. Replacement requires no changing of mechanical hardware, and packaging is compatible with many gearboxes, brackets, pulleys, and X-Y stages for use with stepper motors.
Eastern Air Devices Inc., 1 Progress Dr., Dover, NH 03820, FAX (603) 742-9080; E.P. Electronics Int'l Inc., 21 Amber St, Unit 2, Markham, Ontario, Canada L3R 4Z3, FAX (905) 475-0821.

Thermometers

OS520 Series of handheld infrared th

Software lets engineers achieve their true potential

Software lets engineers achieve their true potential

CAD and other software packages give engineers a great deal of flexibility, but companies using the software are demanding accountability.

Design News: What do customers want from CAD companies?

Weyand: First, engineers want software that is easy to use, that can do their whole job and enable them to work in a concurrent product development environment. Second, customers are looking for a single source to supply their CAD/CAM/CAE/PDM needs. They don't want to be system integrators--they want their software partners to provide the total integrated solution. But software is only part of what they need and want. They also want services. They know they need software implementation services and integration in order to save time, and saving time to market is the great driver. They're looking for a design-automation solution, and they don't care if it comes from design or manufacturing.

Q: What does software do for engineers?

A: It enables them to reach their true potential in product design. It does that by taking away the drudgery from the design process so engineers have more time to do the experimentation with different design approaches that they were trained to do. In that sense, software makes the engineer's career more fulfilling.

Q: What's the key measure of software effectiveness?

A: Of all the benefits, the key measure of success in CAD and its implementation is, as it is for most things, return on investment. There are lots of CAD products for engineers to choose from. They want the one solution that gives them the quickest time to market and highest return on investment.

Q: Why did Ford decide to standardize on your I-DEAS Master Series software?

A: There were several reasons, but primarily they wanted someone to partner with who could provide a software product for complete vehicle design. Ford's objective is to accelerate time to market, but they know that the advantage of software is as much in the implementation as in the technology. Software companies today need to understand what it takes to help global companies and their suppliers be more successful. In the case of our partnership with Ford, we have built a staff of more than 160 people in Dearborn, MI, dedicated solely to supporting Ford and its suppliers in the implementation of I-DEAS Master Series software.

Q: On another level, what is the status of the UNIX platform vs. the NT platform?

A: The NT platform is growing, but manufacturing companies won't abandon UNIX rapidly. There is a heavy investment in UNIX, including companies investing in developing their own languages for UNIX.

Q: What are the barriers to success in using CAD?

A: The barriers are not in the technology. The technology behind our software and many others is excellent, and easy to use. The barrier to success is in the implementation of CAD. To implement CAD properly, most users need help in integrating their current engineering activities and existing engineering data.

Q: What part of the world will see the greatest CAD ?

A: The Asia/Pacific region represents the biggest opportunity for growth. In Japan, a huge number of users currently use 2-D tools. During the next few years, many will be transitioning to 3-D tools to further increase productivity. China also represents a sizable opportunity. By the year 2000, all design there will be done electronically.

Q: What do CAD developers have to do to increase CAD usage?

A: The key is to make tools that help engineers get their jobs done better and faster. Customers want tools that contain innovative and productive user interaction technologies, and that deliver the breadth and depth of functionality to enable companies to develop complete digital prototypes. They also want those tools to facilitate an environment where all team members can work concurrently. Today's design environment is often globally distributed, and it's critical that CAD tools effectively support these global product development teams. Finally, firms large and small are working more and more closely with suppliers.

Hot products

Hot products

Composite stops pump catastrophe

When a catastrophic failure occurred to one of J.R. Simplot's horizontally split case pumps, it could have caused severe case damage. Luckily, the pump had been modified and the original stationary wear rings and bushings lined with Xytrex(R) 451, a PEEK/-carbon fiber composite from EGC Corp. During the failure, when the boiler feed water hit about 220F and the discharge pressure stood at 580 psi, the material retained a sufficient amount of strength and lubricity to prevent the dynamic contact of adjacent metal components. "Xytrex 451 saved us $15,000 to $20,000 in repairs that would have been required if the pump had been fitted with the original metal parts," explains Darell Henderson, maintenance superintendent at J.R. Simplot.


High flow highlights this composite

LNP Engineering Plastics has introduced a high-impact, 30% glass-fiber-reinforced nylon 6 composite called Thermotuf(R) PF-1006 HI EP, for "Exceptional Processing." Containing a proprietary set of additives, the new composite is said to offer superior surface finish, higher melt flow, greatly reduced cycle times, and lower mold and stock temperatures than other standard nylon 6 resins. "This composite offers over 50% greater impact strength over a standard glass-fiber-reinforced nylon 6. And, because it is an easy flow material, molding cycle times are greatly reduced, resulting in higher productivity and significant cost savings for processors and OEMs," says Jamie Tebay, Thermotuf product manager.


Rotary vanes need no oil lubrication

OSHA continues to limit the amount of oil must that can be exhausted from pneumatic systems into the workplace. In response, Spaulding Composites Co. has introduced Spauldite(R) LF-1127, a formulation that eliminates the need for oil lubrication in such components as vanes in compressed-air-driven motors. The new laminate retains most of the advantages of other Spauldite vane materials, including dimensional stability, with the added feature of being internally lubricated. Initial test results in air-motor applications have been positive, with wear being much less than standard vane laminates.


Foam gets to core of composite problems

Isorca, Inc., a privately-owned contract R&D company for the composites industry, has introduced Alba-Core(R), a matrix of glass microspheres bonded with just enough resin to make a robust material. Open spaces between the microspheres, as well as inside them, give this core a much lighter density than conventional syntactics, according to Isorca's Steve Katz. However, due to the way that the product is made, it becomes a closed-cell material, with minimal moisture absorption. The material can be made with a variety of thermoplastic or thermoset resins in flat sheets, put on a scrim like balsa, easily machined, or molded to shape.


Tubing targets medical instruments

Polygon Co. has announced the development of PolyMed Generation II composite tubing, available in a small (2 mm) diameter. Believed to be the first continuous reinforced composite tubing of this size, the tubing was designed to meet the stiffness requirements needed by the medical industry for minimally invasive surgery. Applications include: scissors, graspers, and electro-cauterizing devices. The tubing has enhanced physical and electrical properties, as well as better strength-to-weight ratios, than comparable metal instruments, according to Larry Horine, sales engineer.


Bridge benefits from composite beams

Tom's Creek Bridge (Blacksburg, VA) reopened to traffic recently as one of the first composite short-span vehicular bridges in the U.S. Composite beams made by STRONGWELL replaced the corroded steels beams supporting the bridge. The 8 36-inch beams comprised part of a joint development project with Georgia Tech for the government-sponsored Advanced Technology Program. Using a new optimized shape (twin webbed cellular I-section with transverse stiffeners), the bean is pultruded from a composite matrix of carbon/e-glass-reinforced vinyl ester resin. The design significantly improved the flexural modulus and torsional bending over the present fiberglass I-beam design, according to John J. Kesko, one of the project designers and an associate professor at Virginia Polytechnic Institute.


Composite bridges another gap

One of Europe's largest glass-fiber-reinforced plastic (GFRP) bridges opened recently in Kolding, Denmark. The Fiberline bridge project brought together several key sponsors, including: profile manufacturer Fiberline; resin supplier Jotun Polymer, the City of Kolding, and Owens Corning. Measuring 40 meters long and three meters wide, the bridge is predominantly designed for pedestrians, but will also carry bicycles, motorbikes, and snow-cleaning vehicles weighing up to five metric tons. The structure consists of 15 different types of pultruded profiles with a ratio of 60% glass fiber and 40% resin. The Owens Corning product used is roving 2043, 2500 tex. The bridge weighs about 10 metric tons--less than half the weight of a similar steel bridge.


System aids composite inspections

UCAR Composites Inc., a company that develops and provides precision tooling for the composite industry, has integrated the FaroArm(R), a portable measurement arm designed with six- and seven-degrees-of-freedom, as well as FARO's AnthroCAM(R) 3D measure software, into its Integrated Manufacturing and Inspection System. This enables UCAR to conduct inspections and check surface profiles of aerospace tooling at vendor sites and analyze the collected data. Valisys(R) software integrates geometric dimensioning and tolerancing (GD&T) standards into the process. Each on-site inspection--formerly requiring at least three hours--now takes only a half hour. Because the FaroArm is portable, evaluations can be conducted earlier in the process, avoiding schedule delays.

CAD helps build an Ego

CAD helps build an Ego

Many folks inclined to build their own cars go out into the garage and start bolting stuff together. Swiss automotive service firm Rinspeed had something a little more sophisticated in mind when it approached TLC Carrossiers Inc., a five-person shop in West Palm Beach, FL, with a heck of a job: design and produce a one-off roadster for the 1997 Geneva Auto Show.

Nice work if you can get it. The catch? The car had to be ready to drive in just six months. "This kind of job would typically take about a year," says TLC Carrossiers President George Balaschak. "I knew we needed engineering software on par with what the Big Three use in order to succeed on this project." TLC selected Pro/ENGINEER from Parametric Technology Corp. (PTC), Waltham, MA, at the outset of the project.

The resulting vehicle, christened the "Mono Ego," demonstrates that the creation of world-class, low-volume cars is no longer the domain of the Big Three. In just six months the Mono Ego went from a concept to a high-performance, street-legal concept-car capable of a top speed of 154 mph. And it moves with style: the 15-ft-long roadster displays graceful curves in the flavor of the Monoposto Grand Prix race cars of 50 years ago. The tricolor and angels paint scheme is by French fashion designer Jean-Charles de Castelbajac. The clear plastic driver's seat is decorated with colorful feathers.

Mechanically, the roadster's unique aluminum carapace and framework contains a vehicle that is very modern inside. Off-the-shelf components include the powerplant, drive-train, and brake system and helped make the development cost-effective. A supercharged Ford Cobra 4.6-liter, 4-valve V-8 engine provides 400 horsepower. The manual transmission is a Ford T-45. Ford also supplies the rear axle, which is from a Thunderbird/Lincoln Mark VIII. Balaschak avoided cutting down the drive shaft by moving the linkages further inboard. The custom tires are from Dunlop, feature hand-carved treads, and cost $60,000 a pair. The rear tires are different than the front, by the way, and constitute a second unique and expensive pair.

"What we have demonstrated is the ability to operate at a world-class level in the design and manufacture of concept and show cars," Balaschak says. "And we are now moving into new areas because of the capabilities that mechanical design automation tools can provide us."

In other words, CAD/CAM and advanced engineering tools are clearing the way for small shops like TLC to not only be creative, but also be efficient producers of finished designs.

Gearing up. Balaschak spent 22 years as a mechanical engineer at Pratt & Whitney, and more than a decade restoring cars and building boats, generally using the aforementioned bolting-stuff-together method. New cars, particularly unique ones, require a more methodical approach. Wanting to take that next step, Balaschak started TLC Carrossiers in 1990 with the purpose of developing and manufacturing a low-unit production car that recalled the outre coupes of the 1930s. The result was the Talbo. The aerodynamic body, chassis, coachwork, and the stainless-steel and mahogany trim were all produced in-house. TLC produces two or three Talbos per year.

The Talbo project pushed the company to seek out methodologies to support the creation of one-off and low-production cars. Balaschak used AutoCAD from Autodesk, Inc. (Sausalito, CA) to design the chassis, suspension, interior and exterior trim and other components of the Talbo. He also used it to direct the laser-cutting of certain pieces of stainless-steel trim. According to Balaschak, "doing it by the numbers" has enabled his company to enjoy the benefits of the repeatability and precision that any car company needs to survive in a tough industry.

"Maybe the Italians can get away with beating body panels into shape over tree stumps," Balaschak quips, referring to the time-honored, "hand-crafted" approach reportedly still employed by some Italian sports car companies. "But I can't."

In addition to enabling TLC to meet Rinspeed's strict time constraints, Balaschak estimates that the implementation of Pro/ENGINEER saved his client $150,000. "If the job had been proposed using traditional 2-D methods it could not have met the cost and time targets, and probably would not have been started," he says.

Tame that clay! Like many cars, the Mono Ego began life as a small clay model used to show the customer the basic styling concept. Despite all the advances in CAD and electronic styling, lots of designers still like to work out concepts in clay. "Clay has no discipline," Balaschak says. "I used to like that about it."

While this undisciplined medium gives stylists license to freely explore shapes with their hands, it has no memory. Often times, the designers decides that he or she liked a previous incarnation that, due to malleable fate, no longer exists. For this reason, Balaschak decided to go through the process of finalizing the design for engineering purposes electronically.

The initial clay representation provided a starting point for the electronic design process. Balaschak used a FaroArm digitizing arm from Faro Technologies Inc. (Orlando, FL) to input the geometry of the clay surfaces into Pro/ENGINEER. The FaroArm is a portable measuring device with a three-dimensional articulated arm that measures and captures surface features. To take a measurement the user simply touches the object to be measured with the probe at the end of the arm, and presses a button. Data can be captured as individual points or streams of points. These data are analyzed by the system's digital signal processing software and communicated by a RS-232 serial line to a wide variety of engineering software packages, including Pro/ENGINEER.

The FaroArm cares little about size limitations and TLC engineers used the same procedure to digitize critical off-the-shelf components, including the Ford engine and manual transmission, Eibach suspension, and the Hyundai headlights and taillights. Appropriately scaled, these digitized models enabled the design team to ensure all components would fit inside the underlying ribs-and-stringer assembly.

The front and rear lights posed an interesting challenge. These are important for the Mono Ego to attain street-legal status. However, the track racers the car is based on did not need lights. Balaschak did not want to spoil the look of the Mono Ego with incongruous lights, but TLC did not have the resources to develop brand new assemblies. Fortunately, Hyundai had developed head- and taillights for an as-of-yet-unnamed car that possess the appropriate "racy yet classic" lines. TLC bought a set, digitized them with the FaroArm, and designed the car to fit the lights.

Several Talbo components, including some features of the chassis, made their way into the Mono Ego. Balaschak retrieved the appropriate model files from AutoCAD and translated them into Pro/ENGINEER files where they could be turned into solids and checked for fit and interference on the new car.

Structurally, the Mono Ego has two main features: the tube-like body and the contoured fin-shapes on either side of it. "It was important to nail down the proper relationship between these aspects," Balaschak says. The parametric modeling capabilities of Pro/ENGINEER enabled the TLC team to explore thirty design iterations in just a few days. Furthermore, each iteration was available on file so designers could recall previous features that looked better on second thought.

Electronic surfaces, solid components. The placement of all components was done in parallel with the design of the body surfaces, making it possible to design for aesthetic and packaging considerations simultaneously. Using the system's surface design capabilities, TLC was able to complete iterations of the body surface in minutes, rather than the days it would have required to alter clay models. By using various lighting effects and changing the position of the car on screen, they were able to evaluate subtle changes to the surface design.

"With an electronic model of an automobile you need to see highlights and shadows and consistency of curves and clearances," Balaschak says. "The magic is in being able to move the light simulation over the product model so you can really observe, really look at your design critically. I could roll the car around on screen and say 'this looks like a kink, so I should make a change.' It worked. There were no surprises. The car looked just as we expected."

At the same time the body surface was being created, the system's interference checking capabilities and parametric nature allowed TLC to test the geometry of various components against the ribs-and-stringer assembly and body surface to find the optimal fit. "I moved the fuel tank about ten times before I found the right combination of geometry and space under the body surface," says Balaschak. "Whenever I changed one dimension the system automatically updated the geometry for related components. It saved a lot of time."

The software's product modeling and interference checking capabilities also made changes in the placement of the radiator easier. The Mono Ego inherited its radiator from the Talbo and the original AutoCAD radiator geometry was transferred into Pro/ENGINEER so it could be checked for interference with other surrounding components. "I knew what radiator I wanted to use and I already had the surface skins and the chassis in the product model," says Balaschak. "So, I floated the radiator until I found the right placement. Then, with the radiator in place, I was able to model the brackets that would complete the part interface."

With the individual components of the ribs-and-stringer assembly in an electronic format, TLC was able to rapidly cut the parts and get the Mono Ego on the road. Balaschak wrote the finalized design files to disk on a Friday afternoon. He took the disks down the street to Westgate Sheet Metal, where laser-cutting of the ribs and stingers began almost immediately. The components were cut and polished by Saturday. Assembly was completed by the following Tuesday. And Balaschak was driving the Mono Ego for promotional videos that Friday.

Ready for their next project, TLC is already involved in plans to build another show car that will bring the Alfa Romeo 8C 2900 into the 21st century. All he needs is a customer with enough money to buy one. Beyond that, Balaschak visualizes the TLC of the future as a producer of personalized low-volume cars that are competitively priced for the consumer market. "I see it as an interesting engineering and business challenge," he says. "It is going to require advanced engineering modeling to get it done and excellent presentation models to sell the idea."


Major component, service and engineering tool suppliers for the Mono Ego
Dunlop Tire: Hand-cut prototype SP9000-series tires
Ford Motor Co.: Cobra 4.6-4V engine and T-45 transmission
Eibach Springs: springs, shocks, and anti-roll bars
Kenne Bell: supercharger
Anterra Wheels: wheels
Hyundai: headlights and taillights
Westgate Sheet Metal: laser cutting
Kruse Tuning and Design: panel beating of body surface
German Classic Interiors: interior up-holstery
Recaro: seat
Autodesk: AutoCAD for 2-D design
Parametric Technologies Corp.: Pro/ENGINEER for 3-D design
Faro Technologies: FaroArm digitizing machine
Application Digest

Application Digest

A simple way to predict molded-in stress
By Nancy Hermanson, Medical Market Technical Leader, The Dow Chemical Co., Midland, MI

Polycarbonate is desirable for use in medical device applications where clarity, heat resistance, and toughness are key requirements. But while the material has a good balance of physical properties, its chemical structure allows the penetration of certain types of solvents into the polymer matrix, causing localized swelling. This swelling reduces the glass transition temperature, creating a greater potential for crazing or cracking.

Scientists have long known that stressed polycarbonate has a much lower resistance to chemicals, and there are theoretical methods for predicting the stress level. But up until now, there was no easy way to determine it experimentally, meaning that parts would often require an annealing process--whether they needed it or not. However, researchers at Dow Chemical have now devised a simple test based on the solubility parameter, which takes into account the correlation between the critical strain for the onset of crazing or cracking in the polymer and the solvent-polymer interaction.

Studies have shown that when the solubility parameter of the solvent nearly matches that of the polymer, the polymer will probably be soluble or partially soluble in the solvent. As the difference between the solubility parameters increases, the polymer's resistance to failure under stress should improve.

In Dow's test, a combination of two solvents--ethyl acetate and hexane--are used in various ratios in order to vary the solubility parameter and observe the corresponding crazing of molded polycarbonate samples. The solubility parameter for ethyl acetate is 8.91 and for hexane is 7.27, while the solubility parameter for polycarbonate is 9.8. A stressed polycarbonate sample is exposed to a specific concentration of ethyl acetate in hexane. After one minute, the solvent is washed off and the part inspected for shiny, silver streaks or faint hairline cracks. Crazing in the main area of the part is more indicative of excessive stress, while slight crazing in the corners of the part is not.

If crazing is observed, the test is repeated with a new part and a lower ethyl acetate concentrated mixture. The part's critical strain and stress is determined as the lowest concentration at which crazing still occurs. The molded-in stress can then be determined from the accompanying chart, which plots critical strain of polycarbonate as a function of the concentration of ethyl acetate in hexane.

To speak with a Dow Chemical representative, call 1-800-441-4369.


Achieving long-life aluminum parts

Chris Jury, Vice President Luke Engineering & Mfg. Co., Wadsworth, OH

Engineers have long known that hardcoat anodizing of aluminum components increases wear and corrosion resistance properties. But its uneven microscopic structure also forms an excellent foundation for subsequent treatment with fluoropolymer resins, which are used to increase slip and release properties. Together, these two processes form a very hard, self-lubricated "synergistic" coating system having a wide variety of practical applications.

The most common lubricated hardcoats consist of a hard anodic coating and a dry solid-film lubricant. The underlying hardcoat structure provides excellent topcoat adhesion to the base, while the resin envelope provides enhanced corrosion and chemical resistance. In this two-step process, a resin containing either PTFE or MoS2 is bonded to the surface of the hardcoat. Air drying or thermosetting (350 degrees F cure) resins are also available.

Taking the concept one step further, Luke Engineering developed the first PTFE-impregnated hardcoat, called Lukon 24. Performed in-line without unracking the hardcoated part, the impregnation process is simple, direct, and does not require a heating cycle. The loosely adherent PRFE retained within the hardcoat structure significantly reduces friction and wear; in one example, the wear life of a hardcoated hydraulic piston was increased by over 400%.

Lukon 24 is also an efficient anchor layer for FDA-approved Teflon(R). These fully fused (700F cure) topcoats, which are frequently used to provide molds and kitchenware with excellent release and non-stick properties, can be directly applied without primers or intermediate coats.

To speak with a Luke Engineering applications engineer, call (330) 335-1502 or fax (330) 336-6738.

Engineering News

Engineering News

Simulation gets real

Cambridge, MA --No plan survives first contact with the enemy. This military maxim applies equally well to engineering, where a corollary might read: No design survives first contact with reality. In either case, planners strive to incorporate more real-life variables into their models, if only to avoid uttering those famous last words, "It looked good on paper."

The connection between the arts of war and engineering is not lost on Warren Katz, co-founder of MAK Technologies, Cambridge, MA. A veteran developer of interactive simulations for the Department of Defense, Katz is working to incorporate computer-aided design and engineering technologies into simulations of unprecedented detail and realism.

"Current simulations resolve the interaction of entities with rules," Katz says. "We want to resolve them with physics."

For example, if a tank fires at another tank in a conventional simulation, the round has a certain probability of hitting the target based on programmed variables, such as terrain, relative motion, visibility and weapon accuracy. If a hit is obtained, rules determine what the results of that hit are by calculating the round's penetration value against the target's armor rating. Generally, the target unit can be eliminated, forced to operate at some pre-determined reduced capacity, or is unaffected.

Such outcomes are fine for wargames, where the goal is to approximate battlefield results. However, Katz hopes to be able to move simulations into the realm of design tools by substituting appropriate engineering software for rules-based outcomes. In the engagement above, the tanks would be CAD assemblies, with each component modeled individually. The hit would be resolved using a shock-impact physics code, such as MSC/Dyna. Boundary conditions would be determined from parameters extracted from the simulation engine. Actual damage would be calculated, and the assembly model of the target updated to reflect the damage with new kinematics based on component deformation.

"This way, you would know what happens to the turbine blades of an engine when a depleted-uranium anti-tank round hits hull encasing the engine compartment," Katz says. "You might want to beef up the armor in that area or select different materials or layouts."

Game, not play. The modern military simulation is descended from the "kriegspiel" of the Prussian general staff in the 19th century. That innovative and efficient body determined much of the fog of war could be dispelled with markers representing military units that officers maneuver on a map of a hypothetical battlefield. Rules defined the constraints of unit actions, such as how far a battalion in column can travel down a road in the rain, and the outcome of events, such as an infantry rush at enemy breastworks.

Despite the ironic association of war with game, planners used the kriegspiel to design campaigns and engineer strategies and tactics. The value of the Prussian general staff system was aptly demonstrated in the wars against Austria in 1866 and France in 1871. However, the danger in allowing the simulation too much gravity was revealed when the timetables of the infamous Von Schlieffen Plan drove Germany, and Europe, to ruin in the First World War.

A simulation is only as good as its rules. If the rules do not reflect reality, then the simulation is diminished as a design tool. Worse, the simulation may produce spurious results that are misinterpreted as realistic outcomes. These "artifacts," as they are called, can lull designers into a false sense of security and are a reason skilled analysts are required to scrutinize the results of complex simulations.

One way to remove artifacts is to take the job of simulating human behavior away from the computer. Computer opponents in military simulations are notoriously predictable, once an experienced human participant divines their strategies. Simulator developers often found that trainees were playing against the simulation's artificial intelligence (AI) rather than operating their equipment in a realistic manner. Such situations can actually produce negative training effects, as a real enemy in the field cannot be counted on to act as dumb as the computer.

MAK has, somewhat stealthily, created the standard method the DoD uses to link its simulators together, enabling mock-engagements with thousands of participants. The Distributed Interactive Simulation (DIS) evolved out of the Defense Advanced Research Projects Agency (DARPA) SIMNET (SIMulation NETworking) program expanding single task trainers into networked team trainers. SIMNET has produced over 300 networked simulators with the technology that was to develop into DIS.

DIS the enemy. As Katz explains, the foundation of DIS is a standard set of messages and rules, called Protocol Data Units (PDUs), used for sending and receiving information across a computer network. The most common message is the Entity State PDU which contains data about an entity's position and velocity. By using the position, velocity, acceleration, and rotational velocity data, a receiver is able to determine a vehicle's position before the arrival of the next PDU, thereby reducing consumption of network bandwidth. This enables most of the processor-intensive functions, such as model rendering, to be handled locally with only behavior data passing over the network.

Using this technique, DIS is able to limit the amount of data an average simulator transmits to approximately 250 bytes per second. Optimizations, such as dead reckoning, permit very large virtual battles to take place. The largest DIS exercise, part of DARPA's Warbreaker program, had 5,400 simulated entities interacting in a single DIS virtual world.

The DoD's Defense Modeling and Simulation Office is seeking to establish a common technical framework to improve interoperability between the wide spectrum of modeling and simulation applications. This common technical framework includes MAK's High Level Architecture (HLA) networking standard that will be a follow-on to DIS.

The HLA defines a set of rules governing how simulations, now referred to as federates, interact with one another. The federates communicate via a data distribution mechanism called the Runtime Infrastructure (RTI) that lets different types of systems interact. These systems can include high-end engineering models that run much slower than real time and simulate individual subsystems with very high accuracy.

According to Katz, the updated HLA standards will permit engineering tools to be incorporated into complex simulations with thousands of accurately modeled entities. The fallout for engineers is that such simulations may soon provide a much more realistic framework in which to analyze designs.

It's not all serious business. Inevitably, perhaps, MAK's simulation networking technology is leading to more sophisticated methods of killing time. MAK is working with partners in the computer gaming industry to develop a new generation of realistic games that can be played alone or over the Internet. These games promise accurate shell trajectories, vehicle dynamics, and explosions. One game, in fact, is being developed in concert with the DoD as a training aid for the Marines. No doubt, the Prussians would have loved it.

Collision course. Networking is just one part of the simulator problem. Rendering complex assemblies in anything approaching real time is challenging for the largest computers. Current practitioners of simulation-based design tend to be restricted to fly-through-type evaluations of static virtual mock-ups in dedicated locations due to the processing resources required.

However, competing graphics standards initiatives spearheaded by Silicon Graphics Inc. and Hewlett Packard Co. promise to speed rendering operations dramatically. Both architectures, SGI's Open GL Optimizer and HP's Direct Model, feature occlusion culling techniques for streamlining graphics processing. In occlusion culling, the rendering engine does not process those components in an assembly that are hidden from the viewer's perspective.

Another important relevant trend is the growing availability of multi-processor systems for the engineering desktop. Such systems enable applications that support multi-threading to farm out operations to whichever processor has available capacity. Even conventional applications can be made to run faster. All major Windows- and Unix-based workstation vendors have multiprocessor computers on the market or in development.

Collision course

Networking is just one part of the simulator problem. Rendering complex assemblies in anything approaching real time is challenging for the largest computers. Current practitioners of simulation-based design tend to be restricted to fly-through-type evaluations of static virtual mock-ups in dedicated locations due to the processing resources required.

However, competing graphics standards initiatives spearheaded by Silicon Graphics Inc. and Hewlett Packard Co. promise to speed rendering operations dramatically. Both architectures, SGI's Open GL Optimizer and HP's Direct Model, feature occlusion culling techniques for streamlining graphics processing. In occlusion culling, the rendering engine does not process those components in an assembly that are hidden from the viewer's perspective.

Another important relevant trend is the growing availability of multi-processor systems for the engineering desktop. Such systems enable applications that support multi-threading to farm out operations to whichever processor has available capacity. Even conventional applications can be made to run faster. All major Windows- and Unix-based workstation vendors have multiprocessor computers on the market or in development.

See a video of this technolgoy by clicking here.

  • Networking standards, such as HLA, for linking simulations with engineering codes

  • Advanced rendering techniques, such as occlusion culling

  • Multi-processor computing systems


Set-top box to convert HDTV signals

Fremont, CA --AITech is developing an HDTV set-top box receiver that will meet new broadcast standards established by the Federal Communications Commission (FCC). Known as ATSC Digital Television Standard (ADTS), it is part of the FCC's approval this spring of digital broadcasting.

AITech plans to deliver the HDTV receiver by the end of next year to meet the FCC's schedule for ADTS broadcast. The company estimates the price at around $400--a fraction of the expected $5,000 cost of a new HDTV set.

HDTV converter box receives a digital TV signal and converts it to a format for analog, or NTSC, sets.

"AITech's receiver represents a product category that will be the highest volume digital receiver in the consumer market," says Jonathan Dassell, an industry analyst with San Jose-based Dataquest.

Virtually every home in the U.S. has one or more analog televisions. When HDTV sets are available, they will display at a resolution of 1,92031,080, but, at $2,000 to $5,000 will likely be out of the average consumer's price range.

AITech's HDTV set-top box will receive high-definition digital broadcast signals from the airwaves or from cable, decode the signal, and convert it to a format that can be displayed on any analog TV or standard VGA PC monitor. The unit will also include an audio decoder to perform digital AC-3 decoding into 6 channels of multi-lingual or surround-sound audio.

If the consumer already owns a high-quality TV with S-VHS inputs, the receiver will provide up to 30% more resolution than analog cable or terrestrial broadcast programming.

"The digital broadcast industry has enormous growth potential," says AITech's Casey Ng. "AITech's HDTV receiver will make digital TV affordable for all, which will connect broadcasters to the viewing audience they need."

Plans for the set-top box draw on many of AITech's existing technologies including: FlicFreeTM filter and patented VSProTM PC/TV scan conversion.


Faster chip handles complex applications

Palo Alto, CA --Echelon Corp.'s new 20-MHz version of its Neuron chip doubles the performance of previous Neuron chips, say company officials. It supports faster response times of 3 to 4 msec across a LonWorks control network and doubles the I/O performance over previous versions.

The new chips further expand the range of high-speed industrial applications for LonWorks networks in variable-speed drives, motor controls, conveyor control, valve supervision, and motion control. Engineers can use the faster chip as an off-the-shelf component to control complex manufacturing processes in environments ranging from clean rooms to textile factories to breweries.

Motorola and Toshiba are offering two different versions of the 20-MHz part. The Motorola part contains 10 kbytes of ROM, 2 kbytes of EEPROM, and 2 kbytes of RAM. The Toshiba part has 10 kbytes of ROM, 1 kbyte of EEPROM, and 1 kbyte of RAM.

Standard features include: three 8-bit pipelined microprocessors, 11 programmable I/O pins, two 16-bit timer/counters, sleep mode, media-independent network communications port, 7-layer LonTalk(R) protocol, unique 48-bit internal Neuron ID, and built-in low-voltage detection.

Both parts are sampling now and are pin-compatible with existing parts in the Neuron 3120 family.


Display design hinges on hinge

Stirling, NJ --Retail is a competitive environment, and companies that put their products on display want potential customers to have a clear view of those products. That's why Thermoplastic Processes Inc. improved the design of its familiar display boxes and bins with the addition of a clear, non-mechanical integrated hinge.

"Clear materials are critical to the display business," says Wes Wheeler, executive vice president of Thermoplastic Processes. "Our objective was to develop an alternative to conventional opaque hinges."

Thermoplastic Processes found that alternative in a coextruded elastomeric substrate sandwiched between two PETG (glycol-modified PET) profiles. Wheeler calls the solution the ExcelonTM hinge. The design is based on SPECTAR copolyester supplied by the Eastman Chemical Co. (Kingsport, TN).

Typically, the display industry uses sheet stock and profiles made of the copolyester for a majority of its display components. "We recognized that the combination of clarity, toughness, and flexibility that made SPECTAR perform so well in other parts of the displays could serve us well for the hinge design as well," Wheeler explains. "Lids get a lot of rough treatment, so the hinges have to be as strong and durable as the unit itself."

Using the one-material system enabled Thermoplastic Processes to offer its customers a completely compatible, lighter, more streamlined, and better-looking product that provides a clear view of the product on display. Moreover, the Excelon hinges can be mechanically or solvent bonded to the sheet components. "These crystal-clear hinges look so good you don't even know they are there," Wheeler adds.


Simulation helps work out design of exercise equipment

Franklin Park, IL --By using Working Model 2D motion simulation software (Working Model Inc., San Mateo, CA) to analyze exercise equipment on a computer, Life Fitness is reducing the costs of physical prototyping, shortening design cycles, and bringing high-quality equipment to market more quickly.

In the past, it took more than a year to finish a series of costly physical prototypes. Now, with Working Model, engineers can visualize and analyze dozens of different variations of mechanisms in two weeks.

Recently, mechanical engineer Chuck Rosenow used Working Model to design the Cross-Trainer, exercise equipment that gives a total cardiovascular body workout through simultaneous movement of the arms and legs.

He focused on two elements an exerciser manipulates: the handlebars and pedals. Rosenow first used Working Model to generate rough shapes for the major parts of the Cross-Trainer. Then he produced linkages for these parts, established bolted and welded joints, and applied forces to simulate the exerciser. He also input the density for each of the links.

Once the model took shape, Rosenow used AutoCAD software (Autodesk Inc., San Rafael, CA) to draw the actual parts and create a detailed 2-D drawing. He employed AutoCAD with a transparent interface to Working Model by using AutoMotion (Working Model Inc.) to export the CAD file into Working Model for simulation.

While running the simulation of the model, Rosenow traced the motions of the handlebars and pedals and quickly checked to see if they were within the appropriate dimensions to provide effective, comfortable exercise.

To analyze stresses at the joints, he took force data from the simulation model, combined it with the geometry from the AutoCAD drawing, and imported the information into Cosmos/M finite element analysis software (Structural Research & Analysis Corporation, Los Angeles). He then ran an analysis to ensure that the links could indeed handle the stresses placed on them by the exerciser. Once the overall design gained departmental approval, Rosenow used AutoCAD to generate detailed engineering drawings for manufacturing.

"We couldn't have achieved the design for the Cross-Trainer without Working Model," remarks Rosenow. "It enabled me to look quickly at over 100 linkage simulations without needing to build physical prototypes, greatly increasing our speed to market."


Miniature motors make mincemeat of Mars

by Mark A. Gottschalk, Western Technical Editor

Seal Beach, CA --Space vehicles are typically thought to push the limits of design like few other engineered objects. So it might come as a surprise to discover that this summer's media darling, Sojourner, perambulated about the red, dusty surface of Mars under the power of eleven nearly stock, commercially available electric motors.

Sojourner Drive Systems
Eleven identical -- and only slightly modified -- Maxon RE016 motors and Globe gearboxes provide power to wheels, steering systems, and APXS deployment arm on the Sojourner Mars rover.

Supplied by Maxon Precision Motors (Burlingame, CA), the identical model RE016 DC graphite-brush motors drive each of the rover's six wheels, provide steering control to the four corner wheels, and power the deployment mechanism for the onboard alpha-proton X-ray spectrometer. Each weighs 38 grams and is 16mm in diameter and 41mm long. Rated at 3.2 watts output, the motors use rare-earth neodymium magnets to attain 86% efficiency.

The motors drive through five-stage, 2000:1 ratio, planetary gearheads manufactured by Globe Motors (Dayton, OH). Engineers at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, CA, modified the gearheads to cut weight and friction by slimming some of the gears and replacing sleeve bearings with ball bearings. The four steering mechanisms receive additional 2:1 ratio right-angle gearsets.

Torque per unit mass was a big design driver, say JPL engineers, but the biggest was survivability in the Martian environment--which makes the selection of a brush-type motor all the more interesting. "Normally you couldn't use brushed motors in the Martian environment," says Howard Jay Eisen, chief mechanical engineer for Sojourner at JPL. "The graphite brushes would just fall apart in the near vacuum due to arcing."

The RE016 motors, however, incorporate a proprietary Maxon technology called Capacitor Long Life (CLL) that "dramatically improves brush life," says Eisen. It consists of a capacitor placed in parallel with the winding segments of the motor. Energy stored by the natural induction of the windings is then dissipated by the capacitor rather than in an arc at the brushes.

Brushless servo motors were considered as well. But their extra electronics and wiring made them less desirable. The rover is insulated, and it couldn't afford the conductive heat loss down additional wiring.

Though nearly stock, the RE016's were slightly modified to address the Martian environment. Changes include:

Castrol Braykote grease--good to -80C--was used on the commutator segments. Engineers specified a 10% Braykote/Freon solution for the motor bearings, followed by a mild bake out.

  • Commutator segments made from a special, high-gold composition.

  • Epoxy encapsulation for the ceramic CLL circuit to prevent cracking from thermal cycling.

  • Specially balanced rotor.

JPL engineers selected a single motor type partly to hold down development costs. In all, they ordered 110 of the roughly $100 motors, and spent just $220,000 to adapt them for the application. They proved so spaceworthy that Pathfinder lander's airbag-retraction mechanism used RE016s as well.

"The RE016 is a fantastic motor," says Eisen, "and with some minor changes we got a motor that really did the job for us."


Light switch has its say

San Jose --A light switch that talks--that's the latest application of ISD's ChipCorder(R) voice record and playback chip. The MemoSwitchTM light-switch plate cover from Logic Labs (Leesburg, VA) records and plays back a 10-second message whenever the switch is turned on or off.

Pressing a button on the MemoSwitch activates the ISD circuit to record a message. Because the chip integrates automatic gain control and filters, it is sensitive enough to let people record messages just above a whisper.

"Perhaps your grandfather doesn't like to use answering machines or your child can't read a hand-written note yet," says Bob Smallwood, Logic Labs' president.

One of the biggest applications may be a kind of electronic string on a finger. "Sometimes it's even hard to remember to check the answering machine or a message board," says Smallwood. Since turning lights on and off is an involuntary habit, Memo-Switch is a simple solution for sending quick messages to yourself, coworkers, or members of the household."

ISD's patented ChipCorder technology is a single-chip solution for voice recording and playback in a variety of consumer, communications, and industrial applications. It uses a proprietary "multilevel" storage methodology in which one of more than 250 distinct voltage levels is precisely stored per memory cell, providing approximately eight times more storage space for any given memory size than the alternative two-level, digitized signal storage technology.

ChipCorder requires no external D/A or A/D circuits or software, and stores voice data directly--that is, with-out using compression or encoding.


16-bit controller gains DSP

San Jose --SGS Thomson Microelectronics has expanded its ST10 microcontroller family with two new chips that handle digital signal processing (DSP). The chips suit embedded applications that require high computational capability but without the costs associated with using dedicated DSP chips.

The ST10R262 and ST10F262 both feature a built-in multiply-accumulate unit (MAC) and a pulse-width-modulation (PWM) circuit. These added features make the chips useful for high-performance servo control operations in hard-disk drives and DVD-ROM players, which typically use more-expensive DSP-based circuits, says the company. The ST10F262 also offers 64 kbytes of on-chip flash memory.

All ST10 family members are based on a 10-MIPS core that features a 4-stage pipeline and a register-based architecture. The two new chips will be available by the end of the year.


Pliers won't corrode or conduct

Pearland, TX --Ever open your fishing tackle box and reach for those trusty pliers to extract a fish hook from the jaws of a "keeper," only to find that they have rusted shut? Plastix Technix says you won't face that problem in the future if you buy a pair of their pliers made of a long-glass-fiber-reinforced nylon 6/6 structural composite. And, if you drop them in the water, they float.

"The environment for fish pliers can be highly corrosive,'' says Plastix Technix's Allen Groseth. "Anywhere you have water, you're going to have corrosion. Even stainless steel will corrode around salt water.''

What Groseth needed was a material that would be durable, yet not affected by salt or fresh water, or fuels. He found that material in Verton RF supplied by LNP Engineering Plastics (Exton, PA).

Groseth looked at other materials, including polycarbonates, before deciding on the structural composite. What he needed was a material that would not only solve the corrosion problem for his 10-inch, needle-nose, fish-hook pliers, but would also do double duty in other industries.

"We wanted a product that was versatile enough to serve the electrical and aviation industries," Groseth explains. "This meant we had to have a structural composite that combined strength and durability with non-sparking and non-conductive electrical properties.

When a technician reaches into a confined space to access wires or components, he needs to feel confident that his grasp has no potential for conductance or sparking. "This uncompromising requirement could only be achieved with Verton RF structural composites," says Groseth.


Ergonomic chair no 'shell' game

Grand Rapids, MI --Kimball International's new Purpose office chair features a shell that consolidates a back rest, seat, and flexible support beam into one gracefully contoured molded part. The shell's ribbed-channel design not only increases the chair's long-term load-bearing capabilities, but lets the user stretch, turn, and recline in comfort.

Office Chair with a Purpose
One-piece, contoured nylon seat/back shell gives Kimball International's Purpose office chair ergonomic and assembly advantages.

By incorporating the flat, ribbed channel into the shell's midsection, the shell does not need a metal support beam, adding to the chair's sleek profile. Moreover, the channel distributes stress loads equally across the shell, while allowing controlled flexibility. Ribbing in the upper back-rest area provides added back support and minimizes deflection. And, by consolidating the back rest, seat, and support beam, the design eliminates a complicated assembly operation, as well as many of the metal bolts and connectors needed in conventional chair construction.

Making the design possible is the use of a black, glass-fiber-reinforced, impact-modified nylon 6. The Ultramid(R) B3ZG6 Q660 nylon, supplied by BASF Plastics (Mt. Olive, NJ), combines high flexural strength with elongation and impact properties. The material meets American National Standards Institute/Business and Institutional Furniture Manufacturer's Association performance standards.

Key to Kimball's selecting Ultramid is the material's ability to mold shells that meet the industry's Back Pull Test. Here, a minimum load resistance of 300 lbs is required, and the chair must withstand a 300-lb drop impact test. Kimball reports that Ultramid's high tensile strength (14,500-21,000 psi) and elongation properties outperformed other materials it tested.

Ultramid also contributes some other benefits to the chair's design. For instance, the material provides the high melt flow characteristics (520-555F) needed to efficiently fill the long, thin mold cavity used to make the shell. Further, the as-molded black shell's surface requires no painting or other secondary treatment.

The back and seat cushions attach to the shell by a snap fit and keylock fastener technique. The chair arms are mechanically fastened to a metal arm strap, which also secures the shell to the base and chair control.

BASF provided the office furniture maker with close technical support throughout the chair's development. Assistance included: structural analysis work in designing the shell; flow analysis to optimize the physical properties; processing aid during molding trails; and product modifications to optimize the material's elongation properties and surface finish.


Embedded apps go desktop

Austin, TX --For the first time, Motorola has optimized a Power-PC microprocessor for embedded applications.

The EC603e RISC microprocessor offers clock speeds of 100 to 200 MHz and dissipates 3.2W at 166 MHz.Starting price is $20.69 for 10,000-unit quantities of the 100-MHz version. The chip is functionally identical to the Power PC 603e, except that the floating-point function is not available.

Motorola designers say the 32-bit EC603e suits such applications as internetworking, telecommunications, industrial control, imaging, multimedia, and consumer goods.

"The high-end embedded processor market is growing at a compound annual growth rate of 30.6%," says Tony Massimini, chief of technology at Semico Research. "It is a market that demands ever-increasing performance but with lower power consumption and at lower cost. Motorola's EC603e is meeting these requirements."

Motorola plans to modify other PowerPC microprocessors introduced in desktop computers and migrate them to embedded systems.