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Articles from 1997 In June


Hot Products

Hot Products

Sealed switches guard against ESD

S Series miniature toggle, rocker, and pushbutton switches have ratings that satisfy dry circuits as well as moderate power applications while protecting circuitry against electrostatic discharge (ESD). UL-recognized for 4A, 125V ac or 2A, 250V ac applications, all switch types are available with a selection of actuator configurations and PC-board mounting styles. Other options include gold-plated contacts, tin-plated terminals, and crimped mounting bracket terminals for self-fixturing during assembly and soldering. For electrostatic protection, actuators are made from high-insulation plastics. Insulating heatshrink tubing and spacing pads that fit between the switch body and PC board provide terminals with additional ESD protection. Pricing for a right-angle-mounting toggle switch is $2.45 each in 1000-piece volumes. APEM Components, http://www.apem.com

Solid-state relays make assembly easy

Designed with the OEM assembler in mind, the new Quick Mount line of solid-state relays replaces screw terminals with 1/4-in quick connects. The relay package is 2x2x1 inch and has a molded-in heat-transfer plate to improve thermal dissipation. The NIF Series of latching relays provides a flip-flop function. Each time a control voltage is applied, the output changes state and latches. Operating voltages of 24, 120, and 230V ac, 50/60 Hz, are standard. The triac output can be normally open or normally closed; ratings are 6, 10, or 20A steady (60, 100, or 200A inrush) with zero voltage or random-on switching. SSAC Inc., http://www.ssac.com

Relay does it all

Omron's G3VM line of MOSFET relays just debuted at the Electronics Industries Forum of New England this spring. This flexible line is available in 4-, 6-, and 8-pin configurations and in industry standard surface-mount and through-hole mounting configurations. Relay specs include output voltages up to 350V dc, 50-mA input, -350 to 350V output load voltage, and maximum output ON resistance of 35{OMEGA}. Plus, the relays handle a variety of continuous load current connections--ac, dc series, and dc parallel--at 120, 150, and 200 mA. Pricing starts at $1.80 each in quantities of 1,000. Omron Electronics, FAX (847) 843-8081.

High capacity, long life in a pushbutton

SCB Series panel-mount pushbutton switches offer high capacity and long life with the precise actuation and reliability of a snap switch, say NKK engineers. This feature combination suits heavy industrial and other applications requiring precision switching and high reliability. Long-life models provide a guaranteed minimum of 5 million operations and are rated at 10A and 1/3 hp at 125 or 250V ac. High-capacity types deliver at least 1 million operations and are rated at 15A and 1/2 hp at 125 or 250V ac. Both versions are UL recognized and CSA certified. Termination choices include 0.187-in quick connect, 0.250-in quick connect, solder lug, and screw types; and three cap diameters are available in eight colors. NKK Switches, FAX (602) 998-1435.

Automotive relay handles flasher loads

A new power relay from Fujitsu handles the high inrush currents of automotive flasher lamps used in turn signals and emergency flashers. Contacts of silver-indium-tin oxide let the relay provide more than 4 million operations at 16V dc, 28A inrush to meet the flasher lamps' long-life requirements. The unit itself measures 15.5x12.1x13.7 mm and weighs 6g. The FBR51-WR can also be used for any low-voltage dc lamp load, as outlined in the part's spec. Coil power is rated at 600 mW, and the part is available in 9, 10, and 12V dc coil ratings. Pricing is $1.19 each in 1000-piece quantities. Fujitsu Takamisawa America, http://www.fujitsufta.com

Sensitive relay offers low thermal EMF

With thermal EMF as low as 0.15 muV, NAiS(R) brand TXS polarized relays suit high-accuracy test and measurement applications. The 2 Form C devices measure 15x7.4x8.2 mm and consume only 50 mW, which extends battery life in portable test equipment. In addition, they eliminate the need for the IC drivers conventional relays require. Models are available for 1.5 to 24V dc operation with single-side-stable, one-coil, and two-coil latching operating functions. Nominal operating power for one-coil latching is as low as 35 mW. Switching capability with resistive load is 1A, 30V dc, maximum switching voltage is 110V dc, maximum switching current is 1A, and minimum switching capability is 10 muA, 10 mV dc. At 20C, operate and release times are 5 msec max. TXS2 12V relays cost $2.41 each in 1,000-piece quantities. Aromat Corp., http://www.aromat.com

DIP rotary switch saves board space

CD Series ultra-miniature DIP coded rotary switches from C&K Components withstand surface-mount process temperatures and are sealed for immersion cleaning. The 8-mm square units protrude 4 mm from a PC board and come with surface-mount, through-hold, or right-angle through-hole terminals. Features include a crisp detent, O-ring actuator seal, and flush or extended actuators. Typical life is 20,000 position changes; contacts are gold plated, and terminals are tin plated. Models come in 10-position BCD and 16-position hexadecimal with real and complement codes available. The devices suit applications that require programming, including communications products, peripherals, computers, and industrial controls. Prices start at $2.40 each in 1000-piece volumes. C&K Components, FAX (617) 926-6846.

Reed relay for high frequencies

Capable of passing up to 1-GHz signals with minimal distortion, ATE Series reed relays from CP Clare suit such applications as IC tester load boards, high-frequency communications products, and mixed-signal testers. Typical operating time is 0.5 msec--faster than most electromechanical armature-style relays. High-speed switching results in faster test times, increasing throughput and decreasing testing costs. Magnetic shielding allows for high-density packing, which custom load boards require. The relays have a typical life expectancy of 500 million operations and a stable contact resistance of 150 m{OMEGA}.They also feature insulation resistance between all isolated pins of 10and a dielectric strength 11{OMEGA} of 1,000V dc/peak ac between switch to coil and shield. Eight different package styles meet most custom designs for existing footprints. Price is $2 each in 10,000-piece quantities. Div., CP Clare Corp., Reed Relay Products http://www.cpclare.com

Find a problem, invent a technology

Find a problem, invent a technology

Innovative technology, new products, and aggressive management will ensure a good future for EG&G, according to John Kucharski.

Design News: What future do you see for companies like EG&G that were part of the defense industrial base for so long?

Kucharski: The next 50 years are going to be even brighter for EG&G than our first 50. As you know, EG&G was incorporated in 1947 by Harold Edgerton and his partners--Ken Germeshausen and Herb Grier--by applying technology invented in an MIT Laboratory. Today, we use basically the same technology in a product line we sell around the globe--flashtubes. In essence, we have successfully shifted EG&G's strategic focus away from strictly defense-centered operations and toward higher-growth, higher-return commercial sectors. But the founders' legacy is still prevalent at EG&G today; find a problem, invent a technology, fix the problem--fundamentally we're still an engineering company.

Q: How important are offshore sales to EG&G, and will they become still more important?

A: We see tremendous sales potential overseas, particularly for our x-ray security technology, Linescan and Z-Scan. Two-thirds of the world's airports use our technology to inspect luggage. We recently acquired technology that allows for the inspection of cargo containers as large as trucks. Many of our medical diagnostics products also have huge potential overseas, where they can help deliver needed medical advances to underserved populations.

Q: What role do you see for the American design engineer in EG&G's future?

A: Although EG&G will take advantage of global engineering and production opportunities when appropriate, the U.S. will continue to be our largest market and our leading source of new ideas for the foreseeable future. We've projected that by 1999 nearly 60% of our sales will come from new products. As the world's largest pool of engineering talent, the U.S. will play a major role in making that projection come true. While our overseas production facilities have grown substantially, about 50% of our activities are, and will continue to be, based in the U.S. We will always aggressively take advantage of opportunities, wherever they exist.

Q: Work on amorphous silicon reportedly is the largest program underway at EG&G. Why?

A: We think amorphous silicon will be a technology platform for the next 20 years. With amorphous silicon, EG&G is creating the next generation of imaging technology: glass panels the size of a pizza box with a layer of complex semiconductor sensors. There's no film to develop, the results are in real time, and there's only a fraction of the radiation and medical waste generated by today's x-rays. And because of its portability, there are outstanding opportunities for industrial applications as well. We expect non-medical applications to make up more than 15% of the amorphous silicon market.

Q: How big are medical devices as a business for EG&G, and how important can they become?

A: Medical diagnostic instruments contributed more than $100 million in sales to our instruments business segment last year. Of course, components manufactured by other divisions also address the medical market. For example, a micromachined pressure sensor from our IC Sensors unit is now being used in IV lines to measure blood pressure during surgery. As I've mentioned, very soon we'll have large-scale amorphous silicon detector panels that will allow real-time, low-dosage digital x-ray imaging. We expect steady growth in that market as the world's population demands medical services at sensible costs.

Q: How does a big company like EG&G create and sustain a culture of innovation?

A: It all goes back to Harold Edgerton, our founder. He was a creative, curious individual, and he encouraged the same from everybody who worked with him. At EG&G you can still talk about problems, and you can still talk about finding interesting, technology-based solutions to those problems. If you look around, I would say that a majority of our senior executives has at least a bachelor's degree, not in physics, not in math, but in engineering. The rest of the senior executives have a great appreciation for the value of the engineering discipline. That makes EG&G a very practical and very innovative place to work.

Cyberpage

Cyberpage

Smart semiconductor search accessible

Want to simultaneously query the web sites of major semiconductor vendors? Then you'll want to check out Smart Semiconductor Search at www.eetoolbox.com/smarsrch.asp. A search queries only the web sites dealing with semiconductors. The search engine is from Electronics Search FAQ, which explains and identifies sources of information.

Fingering prints for verification

A new website from PrintScan International Inc. (www.printscan.com) offers an interactive tour of the company's patented software for fingerprint verification and identification. When you visit the site, you can take a technical tour that shows the type of minutiae extracted and used to provide information on the core system software and see how to calibrate the way a fingerprint is captured.

Supply Chain Link Editor's Choice awards presented

The Supply Chain Link presented its first annual MM Editor's Choice web awards at National Manufacturing Week. The winners were: Best web site for a product manufacturer: Dupont (www.dupont.com)Best web site for an automation or computer hardware/software company: Intergraph (www.intergraph.com). Best web site for a distributor, reseller, or service center: EMJ Metal (www.kilsby-jorgenson.com). Best site for a research facility or university: Argonne National Laboratory (www.anl.gov). Best web site for an association or technical society: Water Environment Federation (www.wef.org).

Safety is as safety does

Safety Link (www.safetylink.com) offers access to the world's product safety approval test labs, standards bodies, and government links. The site is broken down into Product Safety Resources, which include test labs from around the world and standards associations; Safety Articles, Essays, FAQs; Telecommunications Resources Worldwide; EMC/EMF/RFI Resources; Ergonomics and Occupational Health Resources, Quality and Environmental Resources; Newsgroups; and several Internet search engines.

Hubba Hubba Hubble

Check out the latest pictorials of our favorite universe at the Space Telescope Science Institute site,www.stsci.edu/pubinfo/Pictures.asp. You can see the aurora of Jupiter, dust storms at the Martian north pole, the heart of a dying star, Hale-Bopp observations, and galaxies with suspected central black holes. The site is an archive of public photos from 1995 to 1997. Photos from the last shuttle service call are also available.

What's up in flexible cable?

Check out the flexible-cable options available on Olflex Wire and Cable Inc.'s interactive website at www.olflex.com. The site describes the company's cables, accessories, and their uses, and allows users to fill out a request form for custom-designed cable.


Manufacturing Marketplace named outstanding web site

Design News has walls full of awards. Now Manufacturing Marketplace, the home site of Design NewsOnline, has won a major award -- Outstanding Web Site as selected by Webcrawler. "A business super site," the Webcrawler award noted. And this backs up what our Design News readers have told us via e-mail: www.designnews.com helps engineers do their jobs. If you haven't done so, please take a couple of minutes and look at the site. And if you've visited the site in the past, but haven't seen our new, user-friendly home page, come back. Not only does www.designnews.com offer thel atest and back issues, but you can read news from Lexis-Nexis witharticles of interest to design engineers, industry news, and new products,updated regularly.


Hot link

More links are something nearly every webhead loves. We found a site specifically for engineers that can link you to bulletin boards, databases, electronic journals, chat sites, or software repositories.

Internet Connections for Engineers (ICE) (http://www.englib.cornell.edu/ice/ice-index.asp) is maintained by Cornell University and has an extensive catalog of Internet-based engineering resources.

Sensing circuit sets up communications

Sensing circuit sets up communications

Burlington, MA--At roadside weigh stations, vehicle weight is typically displayed inside the control room. A driver must wait for the operator's print ticket to know the vehicle's status.

Remote displays installed in the driver's view get the driver involved in the process. If the scale responds immediately, the driver knows the vehicle is positioned correctly. Weight is read directly, enabling quick response if there is a discrepancy.

After a technician installs a remote display, the receiver's communications parameters are set up to match the weighing amplifier's transmission characteristics. Conscientious setup ensures an accurate readout. Traditionally, display installers determine parameters such as baud rate, data format, and parity from documentation, then use DIP switches to set up the display's receiver. Because various data formats evolved over the years, installing remote displays at weigh stations can prove tricky and time consuming, especially when you consider that documentation is often unavailable. In such instances, most installers rely on a trial-and-error approach to set up communications.

"Distributors in the weighing industry wanted several sizes of remote displays that were quick, easy, and foolproof to install," says Scanning Devices president David Chanoux. The design goal: develop the Smart Remote Display (SRD) so it can automatically determine transmitted output parameters and display correct scale weight without using documentation, programming, or mechanical switches. An installer simply mounts the display, connects to line power, and then connects the signal input.

The design solution combines hardware and software. Engineers used PADS-PCB from PADS Software Inc. to design the circuitry and specify the parts and connections. For software development, engineers turned to Scanning Devices' Excaliber package. Excaliber produces microcode for the microcontroller from the PC's text file. A two-conductor, non-polarized input connection enables linking either RS-232 or 20-mA lines with a single connector. Pushing the learn button starts the automatic communications configuration and makes connection to various signal transmitters fast and easy. "Connecting to a signal transmitter is a snap with the learn button," says Scanning Devices President David Chanoux.

Automatic setup works without a need for knowledge of the transmitting instrumentation. The only requirement: about 50 characters of asynchronous serial ASCII data in RS-232 or 20 mA format. Logic in the circuitry automatically determines the polarity and format of the signal, digitizes the data, and sends it to a Phillips-Signetics 2691 Universal Asynchronous Receiver Transmitter or UART.

While the UART attempts to convert data from serial to parallel, an Intel 8051 microcontroller monitors the UART's success/failure rate and statistically analyzes to minimize failures. Once the transmission characteristics are determined, the microcontroller sets up the UART and stores the setup in an EEPROM. Each time the display powers up, the microcontroller reloads the UART with the correct parameters.

The transmitted signal first passes through two inputs to the voltage-sensing circuit. After undergoing logic operations, the input yields two outputs. Outputs determine if the signal is RS-232 or 20 mA, then route it appropriately through the voltage or current circuit. For example, if the signal is determined to be a voltage, the next step is polarity determination. If it's 20 mA, then active/passive determination is made. An iterative process continues until the correct standard is specified.

The system sets the baud rate after analyzing the minimum/maximum input frequencies. Then statistics on the UART's success rate provide the correct data format. After resolving parity with similar logic, the incoming data are compared to standard manufacturers' message formats stored in the microcontroller. "As manufacturers send us their standard message formats, we just add it to the library and add another loop to the logic," says Chanoux.

More than 200 SRDs are installed at weigh stations across the country. A patent application on the method and apparatus for automatic communications configuration is applied for, but not yet issued. "Easy installation and set up make the SRD a success," says Chanoux.

Additional details...Contact David Chanoux, Scanning Devices, Box 192, Lexington, MA 02173, (617) 272-5135

Other Applications

  • Pressure/temperature instrumentation

  • Rate measurement

  • Counters and timers

PD Ease 2D 3.0

PD Ease 2D 3.0

PDEase2D can handle initial- or boundary-value problems that involve partial or ordinary differential equations; are primarily nonlinear in nature; and are static or dynamic, including eigenvalue analysis. To insure proper handling for each class of these problems, PDEase2D will use different types of solvers. Model size in PDEase2D can include up to 32 simultaneous equations and up to 109 nodes for FEM model size.

The dimensionality of these problems is limited to 21/2 dimensions (that is, problems that cannot reference the third dimension as a dependent variable). However, you can still use the software at different locations of a 3-D model, provided that the geometry and boundary conditions (BCs) are adjusted accordingly. This version will not handle complex type and/or complex eigenvalue problems.

If you use Macsyma software's symbolic math capabilities to develop equations, you can still use them in their final form in PDEase2D. There is no bi-directional interface that can take advantage of Macsyma from within PDEase2D. The only way to pass information between Macsyma and PDEase2D is through the MFE notebook where all variables are accessible to both math engines.

A typical PDEase2D model-definition file is divided into sections. Using PDEase2D's natural language, the problem definition in the equation section can describe complex equations involving partial derivatives, in most cases on one command line. The equation section is where the model's mathematical definition is used, and it can be easily translated into PDEase's notation. PDEase2D is limited to first- or second-order space definition and first order in time.

PDEase2D gives you flexibility as to how BCs are entered. The section 'Boundaries' in the input file is based on a hierarchical structure that divides the model in regions. In every region you define the geometry over which BCs are applied. Regions can be handy in areas where you want to force a finer mesh. By breaking the model into regions in that area, PDEase2D will fine mesh the boundary in between.

With PDEase2D you don't have to specify node or element locations. Based on the geometrical outline you specify, PDEase2D will create nodes and elements inside and at the boundary of the model. With boundary segment words such as arc, you can define with relative ease the outline and any openings in your model. New in this version is the ability to import geometry directly from a CAD program in DXF format. PDEase2D interprets every region in the model, as long as you keep them in separate layers in the CAD and DXF files.

At this point, the majority of the model definition portion is complete. You can watch the program meshing the model, and can also use the "monitors" tool to keep an eye on the convergence of the solution. PDEase2D has an excellent mesh generator that minimizes the relative and converges to the solution. The created mesh is made of triangular isoparametric (quadratic) elements.

Unlike ordinary FEA mesh generators, PDEase2D will refine the mesh only where the error exceeds a user-supplied minimum figure. For unstable nonlinear problems, imposing a single-step convergence criterion will not yield an accurate solution. By breaking the problem into small linear sections, you can use the solution and its corresponding mesh density as the initial values for the next step.

The value of PDEase2D for the scientist or engineer is evident in three areas where it shines: ease in setting up the model, simple FEA node and element creation, and excellent resources and postprocessing tools. By implementing the MFE notebook in this version of PDEase2D, which features a bi-directional interface with Macsyma symbolic math package, Macsyma Inc. is providing the user with the best of both worlds in symbolic math and PDE solvers.


Spec box: PDEase2D 3.0

PDEase2D is a front-end language that can model static and time-dependent problems involving partial differential equations using the Finite Element Method. The program requires a 80486 or better PC with 8 Mbytes of RAM, 10 Mbytes of Disk space, and Windows 95 or NT.

List Price: $999

Macsyma, Inc., 20 Academy St., Arlington, MA 02174, ph: (617) 646-4550; fax: (617) 646-3161

A similar product:

MATLAB with PDE Toolbox - The Mathworks Inc., 24 Prime Park Way, Natick, MA 01760; ph: (508) 647-7000, e-mail: info@mathworks.com

Would you like Design News to review your software? Fax Design News Software Lab, (617) 558-4402 or e-mail us at dn@cahners.com (Internet).

Product News

Product News

Pressure transmitter

The flush-diaphragm C290 pressure transmitter is equipped with a 1/2-inch NPT conduit fitting and cable strain relief allowing for conduit piping to the unit. For non-conduit installations, the C290 will withstand washdown environments.

Packaged in a welded stainless-steel housing, the C-290 provides insensitivity to clamping effects, vibration, thermal shock, and other environmental extremes. Thermal shock, in particular, does not affect the performance of the C-290, which will withstand the low- to high-temperature extremes and subsequent vacuum pressures that result from clean-in-place procedures.

Setra Systems Inc., 159 Swanson Rd., Boxborough, MA 01719, FAX (508) 264-0292.

Front plate

A universal front plate is now a standard feature for the company's Monorail guideways in sizes 35, 45, 55, and 65. The front plate offers improved lubrication distribution, tighter sealing, and improved wiping action on the rail surface. A lubrication manifold provides passageways for lubricant to flow from any of the input ports towards the reversible sealing and distribution plate. Independent lubricant flow is recommended for applications where the guideway is mounted on its side, to prevent lubricant from migrating downward due to gravity.

Schneeberger Inc., 11 DeAngelo Dr., Bedford, MA 01730, FAX (617) 275-4749.

ICs

The S-29XX1A and S-29LXX1A Series of three-wire CMOS serial ICs are pin-for-pin compatible with the most popular 93XX Series. The units are capable of protecting the memory against error or malfunction of the CPU, 50% of which can be protected starting from address 00. Both ISO 9001-certified Series are high-speed, lower-power, lower-operating voltage E2PROMS with wide operating voltage ranges which makes them suitable for telecommunications applications. Each IC is capable of sequential read, and addresses are automatically incremented in 16-bit blocks.

Seiko Instruments USA Inc., Electronic Components Div., 2990 W. Lomita Blvd., Torrance, CA 90505, FAX (310) 517-7792.

Profile cutting

The capability to perform custom multi-axis profile cutting on both open- and closed-cell materials in shapes up to 60 inches long is available. Profile cutting can combine what would have been three or four parts into one seamless product giving users greater freedom in the design process. Applications include shock absorption and noise reduction in the electronics, off-road construction, appliance, and aeronautics markets.

Lundell Mfg. Corp., 2700 Ranchview Lane, Minneapolis, MN 55447, FAX (612) 559-4118.

Spray valve

Model 780S precision spray valve lubricates coil stocks 4 inches or less and dies used in high-speed punching and stamping operations without drips or overspray. Simple design and precision-machined components ensure high reliability and millions of cycles without maintenance. The compact unit can be mounted in any position to accurately spray lubricant onto metal stock or die set.

EFD, 977 Waterman Ave., East Providence, RI 02914, FAX (401) 431-0237.

Sheet molding

EnduronTM is a compression- and transfer-moldable material that consists of thermosetting phenolic resin and high-performance fibers. It provides high modulus, toughness, and flammability advantages in thin-walled electronic-products enclosure applications. The material is available with carbon, aramid, or fiberglass reinforcement. High stiffness and inherent strength allow designers to specify wall thickness as thin as 1.0 mm (0.040 inch).

Fiberite Inc., 501 W. Third St., Winona, MN 55987.

Cords and cordsets

Molded cords and cordsets are manufactured with the IEC 320 C-13 connector in straight and all four angles. UL Listed and CSA Certified, these cords and cordsets are available with SVT 18/3, SJT 18/3, SJT 16/3, and SJT 14/3 cordage. Depending on the cordage used, the cords and cordsets are rated for service up to 15A at 125V ac. A double-shot molding feature encapsulates the crimp connections before they are over-molded in PVC. This eliminates any possibility of an uncrimped strand protruding through the PVC and causing a shock.

Panel Components Corp., Box 115, Oskaloosa, IA 52577, FAX (515) 673-5100.

Analyzer

The Guardian 5000 hipot/safety analyzer incorporates four electrical safety tests in a single unit and allows for any combination of up to 15 tests to be automatically performed in sequence. The Guardian 5000 performs ac and dc hipot, insulation resistance, and high-current ground bond compliance measurements on motor-operated tools, appliances, coils, transformers, and a variety of electrical components and devices. Features such as a wide-range of test voltages, remote interfaces, continuous leakage current monitoring, pass/fail threshold detection, automatic high-voltage shutdown when breakdown occurs, and storage of 50 memory groups makes the analyzer suitable for integration into automated test and production environments.

QuadTech Inc., 100 Nickerson Rd., Marlborough, MA 01752, FAX (508) 485-0295.

Cabinet coolers

Cabinet coolers cool and purge overheated electrical control panels while maintaining sound levels of less than 75 dBA at 3 ft. Incorporating a vortex tube that cools ordinary compressed air to 20F, the coolers circulate air through the enclosure to eliminate high-temperature malfunction. The panel remains sealed so it is protected from washdown and dirt. Compressed-air filters assure no moisture or dust is introduced inside the panel. The units are compact, install in minutes, and have no moving parts to wear out. All NEMA 12, 4, and 4X models are listed by Underwriters Laboratories and are available in cooling capacities to 2,000 Btu an hour.

EXAIR Corp., 1250 Century Circle N., Cincinnati, OH 45246, FAX (513) 671-3363.

Cylinders

Series CA NFPA mounting-interchangeable medium-duty cylinders are available in bore sizes 11/2 to 12 inches with standard hard-chrome and polished piston rods for use with up to 250 psi air or oil. Equipment can be mounted to the four tapped holes at each end of the cylinder; these same four holes can also be used to add a detachable mounting. End caps and tubes are manufactured from high-strength aluminum; the tubes are hard anodized for wear resistance. Options include cushions, stop tubes, stainless-steel materials, and proximity sensor switches.

Advanced Machine & Engineering Co., 2500 Latham St., Rockford, IL 61103, FAX (815) 962-6483.

Energy chain

The Twister Energy chain is for rotary applications used in the manufacturing industry. Snap-open crossbars on both the inner and outer radii provide support for the Twister. The corresponding inner side-plate is thermoformed at an angle to create the appropriate circle radius. The interior side of the carrier is comprised of a narrow connecting piece that is held in place by the crossbars. This independent side part, along with the ability to vary the crossbar width, provides the Twister with flexibility and maintains enough strength to run unsupported lengths.

igus inc., Box 14349, East Providence, RI 02914, FAX (401) 438-7270.

Tubing

Co-extruded tubing products were previously available only on a custom basis. The tubing is available in two formulations--low-density polyethylene-lined EVA or Hytrel-lined PVC--and offers natural translucency for visual contact with the flow, flexibility, and resistance to chemicals and radiation. The EVA tubing is produced from Class VI, FDA-sanctioned ingredients for use with food and beverage contacts.

NewAge Industries Inc., Box K, Willow Grove, PA 19090, FAX (215) 657-6594.

Pneumatic valve

Series 590TM four-way directional control air valve is entirely corrosion proof and protected against the effects of immersion. This makes the valve useful for washdown applications, without the need for expensive waterproof enclosures. Features include 24V dc operation, plug-in electrical connections, flow of Cv 0.8, modular valve banks, integral flow controls, and operation with or without line lubrication.

The Rexroth Corp., Pneumatics Div., 1953 Mercer Rd., Lexington, KY 40511, FAX (800) 489-4188.

UPS family

The 1,000 to 3,000 VA PowerWorks ET UPSs are for power environments where severe overvoltage and brownout situations occur. Multiple battery packs and Cell SaverTM technology minimizes battery usage during normal operation to assure extended run times. By extending the input voltage range, the PowerWorks ET regulates the power in a power surge or sag situation without using the UPS batteries. Battery modules can be hot-swapped allowing users to replace or add modules without powering down connected loads.

Deltec Electronics Corp., 2727 Kurtz St., San Diego, CA 92110, FAX (619) 291-2973.

Tool dispenser

The Micro ATD tool dispenser provides self-service access to replacement machine tooling and industrial supplies in small work areas. This 36- x 24- x 31-inch model can be placed on a tabletop, workbench, or desktop; mounted on wheels for portability; or bolted to the wall or a single machine. The Micro ATD can be configured as a 540-item helix-based dispenser able to handle 18 different items in quantities of 30 each, fully equipped with Multi-Item Retrieval Modules that have the ability to dispense up to 405 items in quantities as small as one, or as a helix/MIRM combination. Four small locker-style compartments handle the dispensing and return of tools.

Vertex Technologies, 1329 E. Kemper Rd., Building 400, Suite 4102, Cincinnati, OH 45246.

Software options

FLASH software factory-installed options for the GPD 515 ac adjustable-speed drive include 1,000 Hz output frequency, traverse control, master/follower ratio control, and PID loop for trim control. The PID loop trim control processes feedback signals such as dancer or tension trim controls. The master/follower ratio control provides the ability to accept a digital frequency reference and multiply by a pre-set ratio value for accurate speed control in textile, wire/cable, conveyor, printing, and web-handling operations. The Traverse Control software option provides the ability to modulate output frequency and modulate the drive's speed reference without a special interference card.

MagneTek, 16555 W. Ryerson Rd., New Berlin, WI 53151, FAX (414) 782-1283.

Voltmeter

Model 347 electrostatic voltmeter makes noncontacting, surface voltage measurements in the range of 0 to plus or minus 3 kV dc or peak ac on conductive or dielectric materials such as plastics, paper, and ceramics. A field-nulling technique achieves dc stability and high accuracy even if the probe-to-spacing changes. This permits measurements of either stationary or moving surfaces without the need to establish fixed spacing to maintain accuracy. The probe design eliminates the need for close-tolerance components, significantly improving noise and drift performance in the presence of contaminating particulates and under conditions of high humidity and wide temperature ranges.

Trek Inc., Box 728, Medina, NY 14103, FAX (716) 798-3106.

Evaluation board

Motion chipset evaluation board shortens the amount of time required to build systems using off-the-shelf motion-control chips. Supporting servo, brushless, and stepper motors this product provides up to 4 axis of motion control and includes features such as S-curve profiling, over-travel limit input, feed forward, and electronic gearing. This PC board accepts incremental encoder inputs with index pulse, and provides either Pulse Width Modulation output, 16-bit analog output, or pulse and direction output. The software package provides low-level direct access to the chipset as well as more advanced functions such as continuous multi-axis contouring and servo tubing.

Performance Motion Devices Inc., 97 Lowell Rd., Concord, MA 01742, FAX (508) 369-3819.

Springs

The helical ribbon, cantilever beam, and slant coil springs are for various applications. The helical spring applies a high unit load making it useful for many static face seals or slow-speed reciprocating applications. The cantilever beam spring is for high-speed reciprocating applications or for moderately fast rotary applications, involving cryogenics or gas-tight sealing. The slant coil spring for both rotary and reciprocating applications has a spring force that is virtually constant over a wide range of deflection. This spring automatically compensates for normal tolerances in the gland and for wear.

American Variseal, 510 Burbank St., Broomfield, CO 80038, FAX (303) 469-4874.

Conduit system

This flexible, liquid-tight conduit system offers double protection from fluids through an internal Buna-N grommet and external twist-lock fitting. In addition to resisting various chemicals, the 150 psig rating assures extreme temperature compatibility. The conduit fitting is suitable for industrial and machine applications, such as liquid-filled gear boxes or storage tanks that require sealed feed-through cable. Threads are 3/8 to 3/4 inch NPT and European Pg 9 to 21. Various conduit fittings and more than 3,500 different styles and sizes of strain-relief fittings are available.

Sealcon, 14853 E. Hindsdale Ave., Suite D, Englewood, CO 80112, FAX (303) 680-5344.

Meter

Model 122 intelligent meter/controller offers a 7-inch square standard switchboard housing that contains analog and digital signal conditioners for direct inputs of TC, RTD, VDC, RMS, strain-gage, resistance, four relays, open-collector transistors, 4-20mA and 0-5V dc analog outputs, RS-232C/422/485 I/O, and dc-dc switcher to power the unit from either 5 or 8-32V dc. Features of the meter include 41 bargraph segments, six-digit seven-segment display, dual-channel differential analog multiplexer, and isolated analog outputs.

OTEK Corp., 4016 E. Tennessee St., Tucson, AZ 85714, FAX (520) 790-2808.

Fastener

EZ-TTM Flex-Toggle fastener offers a flexible cross-member that is folded against the stem for insertion and then automatically springs back into perpendicular position against the back side of the substrate. After tightening, the stem may be trimmed flush with the nut. The EZ-T Flex-Toggle requires only 1/2-inch clearance on the blind side of the hole and the hole size is the same diameter as the fastener. Available in 3/16- and 1/4-inch sizes, this non-corrosive, non-conductive, rust-proof fastener is made of tough Zytel(R) nylon in white or UV stable black material.

T-Plastech Corp., 2700 S. Raritan, Englewood, CO 80110, FAX (303) 761-6004.

Control valve

A motorized flow control valve features high flow rates for applications requiring cost-effective, electric remote flow control. The MFC-16 valve is a cartridge-style unit that uses a 12V dc motor to open or close a rotary spool valve. The unit is designed for size 16 valve cavities and can be built in three configurations for zero to 20, 33, or 55 gpm bi-directional flows. Manual override is now a standard feature on the MFC-16. The valve features two speeds, 3.5 or 7 seconds, for full open to full close.

Source Fluid Power Inc., 331 Lake Hazeltine Dr., Chaska, MN 55318, FAX (612) 448-3392.

Software

EnSight 6.0 postprocessing software allows engineers to visualize larger analysis problems and offers a simple graphical interface that users can adjust according to their preferences and levels of experience. The distributed architecture within Ensight 6.0 allows the system to handle models containing millions of nodes, while optimizing memory use. In one test, a complex 10-million-node model required only 109 Mbytes of memory. Large engineering analysis files can be postprocessed on the same computer server in which they were created. Postprocessing can be done on a desktop workstation, allowing users to reserve more powerful computers for compute-intensive functions.

Computational Engineering Int'l., Box 14306, Research Triangle Park, NC 27709, FAX (919) 481-4306.

Interconnects

Ball-joint bearing interconnect options provide linkage solutions for less than half the cost of rod ends. All four male/female interconnect options are available for maximum installation flexibility with highly reliable, low-cost ball-joint bearings. Bearing surfaces of the shell cavity and ball are close tolerance machined for long life. A precision ball is inserted into the shell, and a precise crimping process retains the ball while providing sufficient movement of the ball without excessive endplay. Maximum angularity and compact size allow ease of installation and broad application parameters in a wide variety of motion-force and motion-control uses.

Tuthill Corp., J.J. Tourek Div., 1800 Touhy Ave., Elk Grove Village, IL 60007, FAX (847) 640-0158.

Driver

Accel32, the DAP driver for the Windows NT operating system, is for the a-Series data acquisition processor boards. Accel32 enables real-time data acquisition and control applications to run under NT. Apart from allowing native 32-bit applications--using the provided 32-bit dynamic link library--Accel32 also supports existing 16-bit DOS and Windows applications. Every model in the entire range of DAP boards has its own on-board intelligence implemented as DAPL.

Microstar Labs, 2265 116th Ave Northeast, Bellevue, WA 98004, FAX (206) 453-3199.

Thermoelectric modules

QualityTEC(TM) thermoelectric modules offer a limitless range of applications at temperature ranges from -150 to 200C. Specially doped ceramic plates assure optimum performance of the TEC under stringent requirements. Maximum current for the single-stage modules varies from 3.3 to 60A. The differential temperature is standard at 64C on all single-stage modules. Dimensions of the modules range from 5 to 55 mm, with heights from 3.3 to 5.8 mm. Modules can be square, rectangular, circular, or have any desired configuration. More than 500 types of standard and custom-designed single- and multi-stage thermoelectric modules are available.

HiTech Technologies Inc., Box 535, Newtown, PA 18940, FAX (215) 321-6067.

Valves

Super Quick exhaust valves improve air-cylinder cycling speed permitting the use of smaller, often less-expensive control valves. Small and lightweight, the exhaust valves feature a molded shuttle design and a full-formed seating surface for high exhaust capacity and long cycle life. Available in sizes from 10-32 to 3/4-inch NPT pipe thread, the units offer lubrication in air cylinders by stopping the back-flow of lubricant, which is common in conventional exhausting through directional control valves.

Humphrey Products Co., Box 2008, Kalamazoo, MI 49003.

Cable carrier

The Twister energy chain cable carrier is for rotary applications, such as articulating robots used in the manufacturing industry. Snap-open crossbars on both the inner and outer radii provide the majority of support for the unit. The exterior, outer side-plate construction is similar to that of the E4/100 modular family of carrier, with application-specific applications. The corresponding inner side-plate is thermoformed at an angle to create the appropriate circle radius. The interior side of the carrier is comprised of a narrow connecting piece that is held in place by the crossbars. This independent side part, along with the ability to vary the crossbar width, provides the Twister with greater flexibility while maintaining enough strength to run unsupported lengths.

igus inc., Box 14349, East Providence, RI, 02914, FAX (401) 438-7270.

Motors

The line of cast-iron BLUE MAX(R) motors includes totally enclosed fan-cooled inverter-duty motors designed for trouble-free operation at just 1/20 of base speed. High-performance windings and other improvements enable these motors to operate at the slower speeds often required by inverter drives, without the need for auxiliary blowers. As a result, the BLUE MAX 20:1 constant-torque motors are built in their normal NEMA frame sizes, making retrofits easy.

Marathon Electric, Box 8003, Wausau, WI 54402.

Encoder

The Ledex AG100PSSI multi-turn absolute encoder is for automated material handling, industrial and plant machinery, foundry equipment, and automated test stands. This unit offers fully programmable 24-bit resolution and is suitable for applications requiring a specific resolution or where electronic offsets are desired. Featuring a maximum of 4,096 steps and 4,096 resolutions, the encoder can have a total resolution of 16,777,216 steps, or can be programmed to meet specific resolution requirements. Output codes are available in gray or natural binary. The rugged design provides a high degree of resistance to shock, vibration, electromagnetic and environmental contamination and has an extended temperature range of -20 to 70C.

Lucas Control Systems Products, Box 427, Vandalia, OH 45377, FAX (937) 898-8624.

Application system

Tungsten-carbide application system applies the material to tools and wear surfaces and parts, extending the life up to 100%. The Carbitron 300 System, consisting of an adjustable power supply and vibration hand-tool, is a heavy-duty unit. Typical uses include stamping punches and dies, cutting tools, forming tools, collets and chucks, forging dies, and machine parts.

Hunter Products Inc., Box 6795, Bridgewater, NJ 08807, FAX (908) 526-8348.

Motor

A-max 16-mm-diameter motor features a rhombic-moving coil design for long life, low electrical noise, fast acceleration, and high efficiency. The ironless rotor allows for zero cogging and simple accurate control. Available with either precious metal brushes or graphite brushes, the power rating ranges from 1.2 to 2W. The motor is available with a single shaft or with a passing shaft. Other standard options include all ball bearings/sleeve bearings and terminals/leads. The motor is 25.4 mm long and weighs 23 g. Ambient temperature range is from -30 to 85C, while the maximum efficiency is 77% depending on the winding.

Maxon Precision Motors Inc., 838 Mitten Rd., Burlingame, CA 94010, FAX (415) 697-2887.

Solder terminals

Solder terminals are manufactured in various styles including turret, feed-thru, bifurcated, and tubular types. They are made from ASTM-16 brass for use with 0.032-, 0.062-, 0.093-, and 0.125-thick PC boards.

Keystone Electronics Corp., 31-07 20th Rd., Astoria, NY 11105, FAX (718) 956-9040.

Autodialing system

This cellular autodialing system can be used as a permanent or temporary alarm-reporting-link when conventional telephone lines are not available. Features include the Guard-ItTM Alarm Autodialer, a cellular phone transceiver, and antenna--all housed in a heavy-duty, weather-resistant NEMA-4 enclosure. Upon detection of an alarm condition, the system automatically calls a list of up to 8 pre-programmed phone numbers until it gets a response. When a connection is made, the system reports the station identity and the specific alarm condition through a digitally pre-recorded voice message. In addition to standard phones, the alarm calling sequence also includes cellular phones, pagers, and voice mail.

RACO Mfg. & Engineering Co., 1400 62nd St., Emeryville, CA 94608.

Couplings

Miniature couplings, u-joints, and precision-machined springs with integrated attachment components are available. Included are couplings with an unlimited variety of customized ends. All products utilize the HELICAL Flexure. The configuration of attachments can be as simple as a plain bore or as complex as a pinion gear. The proper attachment will enhance system quality; minimize assembly production time; reduce the total number of parts purchased, inventoried, and assembled; and result in an overall production cost savings. Flexured couplings and u-joints are backlash free and provide constant velocity rotation regardless of misalignment.

Helical Products Co. Inc., Box 1069, Santa Maria, CA 93456, FAX (805) 928-2369.

Motor-driver packages

The UMK family of high-torque motor-driver packages provides six basic two-phase hybrid step motors matched with compact full-step/half-step stand-alone drivers. Divided into two frame sizes of three models each, these step motors develop holding torques ranging from 22 to 187 oz-inch. Constant continuous torques are available from 50 to 1,000 pps with usable torques available to 20,000 pps. The UMK stand-alone drivers are powered by 115V ac 60 Hz for ease of use on the factory floor. Special circuitry reduces vibrations and an automatic current cutback feature protects the step motor from overheating.

Oriental Motor USA Corp., 2580 West 237th St., Torrance, CA 90505, FAX (310) 325-1076.

Manifolds

Standard and custom manifolds for use with media isolation valves can accommodate aggressive, ultrapure, or temperature-sensitive media in any application. These multi-layered acrylic manifolds feature check valves, pressure controls, regulators, and a variety of fitting and tubing to simplify liquid, air, or vacuum media requirements. Isolation valves include direct, rocker, and toggle styles, available in two- and three-way configurations. To protect the working components of the valve an elastomeric diaphragm provides a physical barrier between the media flow path and the operating areas of the solenoid valve.

KIP Inc., 72 Spring Lane, Farmington, CT 06032, FAX (860) 677-4999.

Motion controller

PMAC2TM multi-axis motion controller features 40 MHz encoder count rates, 18-bit analog outputs, 18-micro-second-per-axis servo update time, a 60 MHz CPU, 120 MHz PWM clock frequency, 10 MHz maximum pulse and direction output frequency, 10 MHz position-compare output update rate, and 100 Mbit/sec optical-ring network update rate. PMAC2TM supports popular controller-to-drive interface standards including plus or minus 10V analog velocity command, plus or minus 10V analog torque command, plus or minus 10V analog sinusoidal phase commands, and direct digital commands for PWM "power block."

Delta Tau Data Systems, 9036 Winnetka Ave., Northbridge, CA 91324, FAX (818) 998-7807.

Cord grips

Liquid-tight PVDF cord grips have Viton(R) form seals, resist most chemicals, and can handle temperatures from -30 to 300F and pressure up to 150 psig. The splines allow for a substantial cable range for each of the 10 basic sizes and cable diameters from 1/16 to 13/4 inches. Threads are 1/4 to 11/2 NPT and European Pg 7 to Pg 48. To install, feed the cable through the fitting and tighten nut for a liquid-tight connection.

Sealcon, 14853 E. Hindsdale Ave., Unit D, Englewood, CO 80112, FAX (303) 680-5344.

Power supply

PW101 family of ITE single-output-switching power supplies provide 25-36W of regulated power and are packaged in a low-profile non-vented case. Output voltages are 9, 12, 15, 16, 18, and 24V dc. No minimum load is required and the unit has both overcurrent and short-circuit protection. The power supplies are useful for Information Technology equipment applications.

Ault Inc., 7300 Boone Ave. N., Minneapolis, MN 55428, FAX (612) 493-1911.

Mechanical conveyor

FILTERVEYOR mechanical chip conveyor has a rotating drum-fine filter that removes large volumes of stringy turnings or chips from the coolant, and filters contaminants down to 50 microns in size. This conveyor performs a two-step process that separates the majority of chip volume. Any fine contaminates missed by the conveyor flow by gravity into the rotating drum-filter unit, where the dirty coolant is filtered, passed into a clean coolant tank, and pumped back to the machine. The FILTERVEYOR can accommodate flow rates of 30g per minute or more and is useful for removing troublesome aluminum fines.

Jorgensen Conveyors Inc., 10303 N. Baehr Rd., Mequon, WI 53092, FAX (414) 242-4382.

Switches

Contrinex(R) inductive proximity switches are self-contained position sensors. The Series 600 offers cylindrical housing switches in either three-wire versions with cable or connector connection options, or two-wire ac models. The square housing units include a terminal box for ease of connection. Series 620 carries all the basic features of the 600 models but can handle increased operating distances. Both Series offer protection against short circuits, overloads, full voltage reversal, and output over-voltage.

Locon Sensor Systems Inc., Box 789, Holland, OH 43528, FAX (419) 865-7756.

Dc servo motors

Brushed dc servo motors with optical encoders are available in 1.5-, 2.25-, and 3.13-inch diameters. Output torques range from 5 oz-inches to 64 lb-inches peak. A variety of integrally mounted rotary optical encoders are available including 200, 500, 1,000, and 2,000 pulse/rev resolutions; index pulse; line drivers; and complementary output signals.

Dynetic Systems, 19128 Industrial Blvd., Elk River, MN 55330, FAX (612) 441-5217.

Paddle latch

No. 3-7921 two-stage rotary paddle latch provides positive vertical and horizontal latching. The latch is offered in a key-locking version, with either carbon steel or 304 stainless steel for the paddle and housing. Used in applications such as door panels made of steel or fiberglass, this latch is recommended for use with the No. 240-52U striker.

Eberhard Mfg. Co., Box 368012, Cleveland, OH 44136, FAX (216) 572-2732.

Die cutters

Heavy-duty, flat-bed, roller-press die cutters are for production die cutting from sheet stock, trimming of thermoformed and other molded parts, or for proofing of flat-bed steel rule dies. The EconoPress units, which utilize standard flat-bed steel rule dies, are capable of die cutting a wide variety of materials at production speeds of up to 800 blanks per hour. Die-cutting capacities of standard EconoPress models range from 42 x 44 inches to 115 x 144 inches. Features include both fully automatic and manual controls, easily changeable plastic cutting sleeves, heavy-duty drive motors, and a variety of safety features.

CORfine Inc., Box 2525, Muncie, IN 47307, FAX (765) 288-9552.

Vacuum pumps

M Series vacuum pumps are for applications where the vacuum source may be exposed to caustic environments. They are constructed of Polyphenylenesulphide which provides extreme corrosion resistance against chemicals including acetone, sulphuric acid, and toulene. The lightweight composite body style is suitable for end-of-arm tooling. The pumps are available in three sizes and provide high vacuum pressure up to 27 inch-hg and vacuum flow capability up to 22.5 scfm.

PIAB Vacuum Products, 55 Accord Park Dr., Rockland, MA 02370, FAX (617) 792-0574.

Controllers

PX Series process controllers employ fuzzy logic algorithms with PID autotune. These controllers "learn" the user's process, using the PID parameters as a starting point for all decisions made by the controller. With a NEMA 4X faceplate as a standard feature, these controllers can withstand hosedowns with water as well as caustic chemicals and harsh environments. Features include 24V ac/dc or 85 to 265V ac input power on most models, configurable menus through a number of display parameters, universal input, eight segment ramp/soak programming, and multiple levels of security to prevent unauthorized use.

TTI, Box 1073, Williston, VT 05495, FAX (802) 863-1193.

Linear-motion system

The Werner Domino Slide linear-motion system is for holding precise locations, and is hand adjustable. Features include high repeatability and a precision micrometer adjustment of 0.5 mm. This system is suitable for precision applications such as inspection equipment, adjustable cameras, and ink-jet heads. The ACME screw-drive mechanism minimizes backlash.

Pacific Bearing Co., Box 6980, Rockford, IL 61125, FAX (815) 962-3818.

Fan

The 5.5-inch-square MS Series ultra-thin axial flow fan develops air flow up to 78 cfm @ 2,800 rpm in a razor-thin 0.79-inch axial length. Noise levels do not exceed 40 dB (A), the unit's service life exceeds 320K hrs under normal operating conditions, the redesigned 5-blade propeller uses a plastic resin, and static pressure will reach 0.18 inches in H2O. A built-in capacitor for the 14W MS14F-BC fan with 115V 60 Hz can operate safely and efficiently with 100V ac 50 Hz or 100V ac 60 Hz inputs.

Oriental Motor U.S.A. Corp., 2580 West 237th St., Torrance, CA 90505, FAX (310) 325-1076.

Software

Hypersignal HAppI (Hyperception Application Interface) creates stand-alone, DSP-based applications for Windows 95 and NT, from visually designed real-time DSP worksheets. These applications may then be used internally or shipped to an end customer. This product leverages many off-the-shelf DSP/Acquisition boards supported by Hypersignal RIDE such that overall product development time for a given project is extremely short. HAppI is useful for creating virtual instruments and sharing simulation/test results.

Hyperception Inc., 9550 Skillman, LB 125, Dallas, TX 75243, FAX (214) 343-2457.

Cylinders

Medium-duty repairable cylinders range from 11/8- to 5-inch bore. Pressure ratings are 150 psi air and 500 psi hydraulic. All cylinders are available in 300 Series stainless steel and standard industry materials. Cylinders are for corrosive environments including food, marine, chemical, paper, and pharmaceutical applications. Cushions, flow control, and magnetic pistons with reed or hall switches are available.

Airoyal Mfg. Co., 1355 Rte. 23, Butler, NJ 07405, FAX (201) 838-2638.

Inspection system

Vision Inspection System-Base is for use in the production of PET containers. It performs on-line inspection of plastic containers for base-related defects. The VIS-B can automatically detect common quality problems such as base folds and off-center gates on containers immediately after exiting the blow-molding machine. The unit, a single-camera vision system, performs non-contact inspection of containers at speeds up to 32,000 per hour.

AGR Int'l Inc., Box 149, Butler, PA 16001, FAX (412) 482-2767.

Screw cleaning

Pressure Blast System is for screw cleaning and molding cleaning using non-abrasive plastic blast media. It is completely self-contained to provide a dust-free, non-toxic cleaning environment and is equipped with a high efficiency dust collector. Molders can save money by eliminating slow hand cleaning and expensive chemical processes.

Maxi-Blast Inc., 630 E. Bronson St., South Bend, IN 46601, FAX (219) 234-0792.

Gasket

A composite EMI/RFI and EMP gasket is constructed from a closed-cell sponge-rubber assembly with a monel wire-mesh insert. A rubber-based adhesive secures the mesh to the rubber after the die cutting and assembly of the rubber; a dry-back adhesive is applied to one side for installation. The gasket is suitable for connecting two electronic enclosures where the junction requires an environmental EMI and EMP shield.

PressCut Industries, 2828 Nagle St., Dallas, TX 75220, FAX (214) 350-4713.

PC board

PC-board indicators EA203, EA205, and EA206 provide two colors of illumination from each LED: red/green, red/yellow, or green/yellow. Considering each Bi-level LED is with three leads, a third color of illuminations is possible when both LED chips are energized simultaneously. Bi-level packaging doubles the number of possible indications to six and maintains a maximum height of 3/8 inch. Operation is at 20 mA or less with a forward voltage of 2.1. Peak wave lengths are 625, 590, and 565 nm with mcd ratings of 50 at 20 mA.

Gilway Technical Lamp, 800 W. Cummings Park, Woburn, MA 01801, FAX (617) 938-5867.

Surface coating

MAGNAPLATE HCR(R) multi-step proprietary coating process produces a harder-than-steel surface on aluminum and aluminum alloys. The coating offers maximum corrosion resistance, permanent dry lubricity, and a low coefficient of friction. It can be applied to parts of any configuration, any weight, and virtually any size or thickness, including threaded members or other close-tolerance parts. Coated parts cannot be damaged in normal use. The coating is integrally bonded to the substrate parent metal, therefore its impact resistance is limited only by the structural strength of the base metal to which it is applied.

General Magnaplate, 1331 Route 1, Linden, NJ 07036, FAX (908) 862-6110.

Contact springs

Miniature gold-plated bellows contact springs are for flexible interconnections. Diameters range from 0.037 to 0.125 inch OD. A convex conical or concave conical tip allows the contact springs to be used in critical interconnection applications where reliability, flexibility, and low force are a must. Contact springs can be used individually or as pairs. They are manufactured from electrodeposited nickel and are gold-plated to MIL-G-45204 to enhance their conductivity and provide extremely low dc resistance with a minimum insertion loss.

Servometer Corp., 501 Little Falls Rd., Cedar Grove, NJ 07009, FAX (800) 785-0756.

Check valves

Check valves are for use in demanding environments. They are molded in Kynar, a polyvinylidene fluoride that is chemically resistant to hot acids, halogens, alcohols, aromatics, oxidants, mild bases, and aliphatics. Check valves are assembled utilizing a non-toxic bonding technique. These valves feature a single sharp barb with no parting lines on the sealing surface of the barb. This design virtually guarantees a leak-proof seal when properly assembled.

Ark-Plas Products Inc., Hwy. 178 N., Flippin, AR 72634, FAX (501) 453-2567.

Core module

PC on a StickTM is a PC-compatible core module that combines a 386 processor, RAM, flash EPROM, real-time clock, serial ports, DMA, chip selects, and a parallel I/O on compact DIMM module. Familiar PC software tools and languages can be used for programming. A wide-operating temperature range, low standby current, and small size make this product suitable for use in industrial controllers, battery-operated systems, and anywhere PC compatibility is needed. PC on a StickTM is based on a 33 MHz Intel 386EX CPU with three 16-bit timers, 2 or 6 serial ports, a Watchdog Timer, DMA controller, Interrupt controller, and Programmable chip selects.

Industrial Control Links Inc., 13620 Lincoln Way, Suite 100, Auburn, CA 95603, FAX (916) 888-7017.

Workstation

Series 4460 PC workstation is for use in Class 1 and 2, Division 1 (groups C-G) hazardous areas and Series 4480 is for Class 1 and 2, Division 2 environments. Totally sealed within a continuously welded NEMA e/4x stainless-steel enclosure, complete with two internal dc fans, the package includes a 14-, 17-, or 20-inch SVGA color monitor, a parallel port, an RS-232 port, an 8-slot passive backplane, up to a Pentium 200 MHz with 128-Mbytes RAM, and up to 2- GBytes hard drive. The Division 1 Series incorporates a microprocessor-based purge system with self diagnosis, while Division 2 units are continuous purge.

Daisy Data Inc., 333 S. Enola Dr., Enola, PA 17025, FAX (717) 732-8806.

Motors

A-max 22-mm (0.87 inches) diameter motors feature a rhombic moving-coil design for long life, low electrical noise, fast acceleration, and high efficiency. An ironless rotor allows for zero cogging and the motor is available with either precious-metal or graphite brushes, power ratings from 3.5 to 6W, and a single shaft or passing shaft. Other standard options include ball bearings/sleeve bearings, and terminals/leads. The motor length is 31.9 mm (1.26 inches) and weighs in at 54 g (1.9 oz). Windings are available to match desired speed with available voltage. Ambient temperature range is -30 to 85C.

Maxon Precision Motors Inc., 838 Mitten Rd., Burlingame, CA 94010, FAX (415) 697-2887.

Air ring

Saturn Maximizer air ring is for extrusion of Polyethylene, LLDPE, m LLDPE, and blends of LDPE. The unit can run higher blow-up ratios with very few limitations. The design and control can be retrofitted into the standard Saturn chambers replacing original lipsets.

Future Design Inc., 38 Holtby Ave, Brampton, Ontario, Canada L6X 2M1, FAX (905) 453-6089.

Indicator

Model 8010 1/8 DIN indicator provides visible indication for most applications, and is available in a choice of red or green LEDs. It can be configured for up to 30 different engineering units, including temperature, weight, pressure, flow, power, and current. A simple operator interface, offers straight-forward menu-driven commands enabling setup and operation. A comprehensive alarm strategy is available including latching or non-latching options, standard relay output, and second and third alarm outputs if required. A RS-485 communication board can be fitted, offering full integration with most instrumentation, including industry standard MODBUS. A 24V dc transmitter power-supply PCB is available as a plug-in option.

West Instruments, 1900 S. County Trail,East Greenwich, RI 02818.

Magnets

FFV Series drawer magnets protect mini-vacuum drying/loading systems from ferrous contaminants. They mount on the throats of processing machines, and feature O-ring seals designed to withstand pressures up to 15 inch-hg without leaking. Flanges are drilled to OEM or customer specifications. More compact units are made from 304 stainless steel and use a single high-energy Rare Earth Power Balanced Magnetic CartridgeTM to collect ferrous scrap and fines.

Bunting Magnetics Co., Box 468, Newton, KS 67114, FAX (316) 283-4975.

Controllers

The 8000 Series of temperature controllers offer the use of either 5A output relay or SSR drive, both complete with replaceable plug-in module. Other features include a second set-point option for alarm or cooling, five-step process error display, and hi-definition scale with ranges for applications from -100 to 1,600C or F. A practical design combined with choice of connection method, clear indication of control and stability and dimensions make the units a suitable replacement control when analogue controllers are a must.

U.S.A. Cal Controls Inc., 1580 S. Milwaukee Ave., Libertyville, IL 60048.

Medical device assemblies

HEPAfiltered manufacturing environment is dedicated to medical device sub and finished assembly. Capabilities include slitting and punching, trimming and bevelling, tipping, bonding, marking, sking, and cuffing. Assembly equipment and facilities include specialty jigs and fixtures, multiple assembly stations, environmentally controlled clean rooms, and flow booth. Inspection, bundling, packaging, and leak testing is also performed.

Vesta Inc., 5400 West Franklin Dr., Franklin, WI 53132, FAX (414) 423-0562.

Gas line heaters

A standard line of gas line heaters is made from a silicone-rubber heating material insulated with closed-cell silicone-rubber sponge to prevent condensation. An optional thermocouple for temperature control is available. The standard line features a 2.5W/in2 on gas line O.D. and can be daisy chained to a maximum of 10A. Features include positive locking heater connectors, snap closures, and quick on/off installation.

Watlow Columbia, 2101 Pennsylvania Ave., Columbia, MO 65202, FAX (573) 474-5859.

Welding tool

TRIAC PID hand welding tool offers a high welding capacity, temperature indication by digital display, cooled adaptor tube for increased operational safety, light weight, and a small-diameter handle for fatigue-proof working. The tool is available with a screw-on draw nozzle for round and profiled welding rods as well as with the complete range of push-fit standard nozzles for welding of rods and films.

LEISTER Elektro-Geratebau, 6056 Kagiswil, Switzerland, FAX +41 41-6607816.

Gage

Model 25DL thickness gage can make measurements from just one side of almost all plastic parts with varying degrees of thickness, geometries, or temperature. The Application Auto-Recall feature permits the operator to recall standard or custom-stored application setups that simplify switching among a large selection of ultrasonic-contact, delay-line, and immersion probes. An extensive internal datalogger allows the operator to store and recall more than 5,000 thickness-reading 10-character alphanumeric Identification Codes. An RS-232 port permits fast test documentation.

Panametrics, 221 Crescent St., Waltham, MA 02154.

Valve

Flex tube diverter valve is for use in either pressure or vacuum pneumatic conveying systems with up to 15 psig pressure differential. This product allows continuous conveying--the ability to shift on-the-fly when handling low-abrasive materials. The sliding flexible tube design is suitable for handling medium- to low-abrasive products such as food stuffs, plastic pellets, and fine materials. The unit can be installed in a vertical or horizontal conveying line. Available in tube and pipe sizes from 2 through 8 inches, the Flex Tube Diverter comes with a choice of aluminum, carbon steel, or stainless-steel metal material contact.

Salina Vortex Corp., 3024 Arnold Ave., Salina, KS 67401, FAX (913) 825-7194.

Cutter

Table-top SA-01 "S" cutter is approximately 16.5 x 9.2 x 14 inches, has a power consumption of 100W, and weighs approximately 77 lb. Features include a small footprint, quiet operation, low energy use, a patented rotary cutter, and no sizing screen.

Nissui Corp., 3510 West Rd., East Lansing, MI 48823.

Hot stamp machines

Vertical hot stamp machines are for small-area decorating. The line includes the SPT 1000 with 1/2 ton stamping force, SPT 2000 with 1 ton of stamping force, and SPT 5000 with 21/2 tons of stamping force. Also offered are the SPT 8000 with 4 tons of stamping force, the SPT 15K with 71/2 tons of stamping force, and the SPT 24K with 12 tons of stamping force for stamping larger surface areas.

Silicone Products & Technology Inc., 1600 Commerce Parkway, Lancaster, NY 14086, FAX (716) 684-0310.

Vacuum pump

COBRA single-stage, direct-driven dry-screw vacuum pump is for the chemical and pharmaceutical processing industries. It requires no intercoolers and offers efficiency and easy maintenance due to its simple screw design. The pump provides vacuum down to 5x10-3 torr and displacements to 1,590 cfm. Advantages include oil-free operation for easy product recovery and no disposal costs; a simple screw design for easy maintenance; single stage with no intercoolers; small footprint for less space requirements; non-contacting parts for longer pump life; and a straight, short flow path for quick discharge so product cannot accumulate in the pump.

Busch Inc., 516 Viking Dr., Virginia Beach, VA 23452, FAX (757) 463-7407.

Spectrophotometer

Portable color-measurement spectrophotometer has 10 nm resolution over the visible color spectrum. Results are reported directly via built-in software and an LCD display. All popular color scales, observer angles, illuminants, and indexes are provided. Quality-control results are directly displayed with user-adjustable limit settings. Up to 1,000 measurements can be identified and stored. The instrument also has an RS-232 port for connection to a printer for direct output of results, or for interface to a computer for downloading and analysis by advanced quality control, color formulation, or point-of-sale software. A docking station is also available for incorporation in a double-wide drive bay in a PC.

Color Instruments Inc., 319 Mola Ave., Ft. Lauderdale, FL 33301, FAX (954) 525-5963.

Engineering Productivity Kit - CAD/CAM/CAE

Engineering Productivity Kit - CAD/CAM/CAE

Software promises perfect plastic parts upfront

Newton, MA--Plastic has revolutionized manufacturing, forming parts of consistent quality, size, shape, and color in one operation and at low cost. As a result, the material has become increasingly popular in many industries--automotive, computer, and consumer.

But producing injection-molded parts often involves a complex operation. Many times plastic parts are not analyzed before production because of the time and expertise needed for simulation. The result: frequent and costly part redesigns and mold rework.

"Eighty-five percent of the part designs we receive require design changes to support the manufacturing process," says Bob Petit, design and analysis manager at manufacturer Nypro Inc. (Clinton, MA). "For a $300 million company like ours, verifying part designs up-front would save us about $200,000 per year."

Moldflow Corp. (Lexington, MA) hopes to make that a reality by enabling what it calls "process-wide plastics simulation." The company aims to bridge the gaps between part design, mold design, and part production through its Plastics Adviser Series software products.

First in the series, Part Adviser enables the part designer to quickly evaluate a plastic injection-molded part for "manufacturability." The software simulates plastics flow and gives practical advice on corrective actions for identified problems. For example, the software tells the user whether a part will fill properly, the location of weld lines, and whether and where air traps will appear. It also provides feedback on how modifications to wall thickness, gate locations, and material selection will affect the part's manufacture.

"Today, analysis is done too late, after the part is designed. At that stage, analysis requires 40 to 60 hours of an expert's time, and a fix, which is needed in most cases, is too expensive," says Lee Malouff, director of engineering services at Black and Decker (Shelton, CT).

Did you know...
76.5% of engineers surveyed use 2-D design and drafting software.
Source: Design NewsMarket Beat survey.

Working directly from 3-D solid models generated in CAD, Part Adviser eliminates the need for data translation, meshing, mid-planing of models, and manual model cleanup. With no previous analysis or plastics expertise, designers can obtain accurate results in minutes rather than days or weeks, says Moldflow.

A special "Confidence of Fill" test helps users determine whether a part will fill, without having to interpret filling pattern and distribution results. A non-Newtonian, non-isothermal solver (patent pending) simulates shear heating, temperature and pressure distribution, and frozen-layer information behind the scenes.

In the confidence simulation, areas of the part model appearing in green indicate a high confidence rating, yellow notes a medium confidence level, and red shows areas with a low confidence rating. Sections showing red or orange may require design or material changes for the part to fill.

"Companies can now benefit from practical plastics manufacturing expertise early in the design process, and avoid costly modifications later on in manufacturing," says Ken Welch, VP of marketing at Moldflow.

Online advisors provide information on plastics manufacturing constraints and how plastic flow behavior affects part quality. Part Adviser is integrated with several CAD systems, including SolidWorks and Pro/ENGINEER. A stand-alone version runs with any CAD package that can generate an STL file.

Additional details...Contact Moldflow at (617) 674-0085, visit http://www.moldflow.com

Staff Editor Anna Allen contributed to this Productivity Kit.


News Flash

Make Web technology work for you

Cambridge, MA-based market research firm Daratech Inc. will sponsor a conference to show how Web technology creates a competitive advantage for manufacturers in the process and power industries.

Taking place July 28-30, 1997 in Los Angeles, Intranet/Web Strategies for Engineering and Manufacturing '97 will explore how Web technologies create highly reliable and expandable in-house networks for collecting and distributing graphics, text, voice, and video data for structured and unstructured engineering, manufacturing and plant design, and maintenance and operations.

For more detailed information and the conference agenda, contact Daratech at ph: (617) 354-2339, fax: (617) 354-7822, e-mail: daratech@daratech.com, visit http://www.daratech.com on the Internet.

PDM implementation takes off

The Kalthoff International (Cincinnati, OH) buying index reveals that an increasing number of companies are in the later stages of evaluating purchasing initiatives for product data management (PDM) and engineering document management systems (EDMS).

Study results showed 47% of discrete and process manufacturers--423 of 904--have active purchasing initiatives underway. Of these, two-thirds indicated they are in the final stages of buying a system--evaluating vendors, implementing a pilot or full system,or upgrading a current system.

For additional information on the index, contact Blaine Clark at (513) 794-3367, e-mail ki@kalthoff.com, visit http://www.kalthoff.com on the Internet.


Simulation perfects life-saving helicopter seat belt

Phoenix, AZ--Traditional helicopter restraint harnesses, designed to maximize a helicopter pilot or crew member's safety, often prove restrictive. Pilots and crew members frequently loosen the restraint systems to gain comfort and mobility, but a loosened restraint system compromises safety.

To address the problem, the U.S. Department of Defense awarded Advanced Structures Technology, Inc. (AST) a contract to design a helicopter crew member pretensioning device (PTD). The PTD enables pilots and their crew to wear restraint systems comfortably until a crash onset, when the restraint automatically tightens around the occupant to reduce injury or improve the chance of surviving a crash.

According to AST, two-thirds of helicopter crash-related injuries and deaths result from upper torso flailing, leading to striking or being struck by objects or structures in the cockpit. To design the pretensioning device, AST needed to know how a body moves through space during a crash. AST engineers accomplished this using Working Model(r) dynamic analysis software from Working Model Inc. (San Mateo, CA) to define the body displacement (flail) envelope likely to be traversed by a helicopter crew member's body during a crash. For this, the design team used Working Model 2D to analyze the human, seat and floor structure, and the restraint harness.

"One of our engineers went through the Working Model tutorial and was up-and-running in one or two days," says James McLellan, AST lead engineer. "What's more, Working Model paid for itself on the first use."

Did you know...
36.1% of engineers surveyed work on Unix systems.
Source: Design NewsMarket Beat survey.

AST calculated flail envelopes for three harness conditions, all with the occupant in the same initial position. The first condition had the harness snug on the occupant to simulate a properly tightened harness or a pretensioned loose harness. The second condition applied a 200-lb preload to the shoulder harness, simulating a pretensioning event on a snug harness. The third condition analyzed had four inches of slack in the harness. In all cases, the flail envelopes of the occupant's head, hands, and feet were tracked for comparisons.

"Mathematically, without Working Model it would have been a nightmare to create the clear picture we needed to develop the PTD," says McLellan.

The AST engineers conducted dynamic simulations using a 50-percentile male patterned after the GM Hybrid III crash test dummy, a 5-ft, 8-inch-tall, 163-lb person. A 5 lb helmet was added for the human model to represent a military flight crew member.

AST obtained the seat geometry by measuring an armored Navy helicopter seat. Next, engineers modeled the floor structure as a horizontal projection of the floor under the seat. This approach offered the largest foot flail envelope.

To obtain the largest head and hand flail envelope, AST did not model the panel, windshield, and ceiling. Instead, it modeled the seat and floor structure as a single unit with slide constraints to enforce motion only in the crash direction.

The resulting model uses a five-point restraint harness that includes shoulder harnesses, seat belts, and a crotch strap. McLellan modeled the shoulder harness as a rope with a spring attaching it to the seat back. For each condition, the spring rate on the short spring connecting the rope to the seat back was adjusted to represent the total spring rate of the shoulder harness.

The Working Model analysis and simulation gave AST engineers a clear understanding of how an occupant moves through space in the cockpit during a crash. This led to the design of a PTD that retracts four inches of shoulder harness slack in less than 35 milliseconds after crash onset, then locks the strap, significantly reducing the occupant's flail envelope.


APPLICATION TIP

Software automates the mold design process

by Peter Brooks, VP of Mechanical Engineering Products Bentley Systems Inc. Exton, PA

In the past, experienced machinists with many years of accumulated knowledge made mold bases. Now, Bentley's MoldDesignTM software takes the "black art" out of the mold design process. The software generates mold designs straight from 3-D solid-model parts, automating the process of designing plastic and high-pressure aluminum injection molds, freeing designers from creating mold plates and components, and detailing holes and slots.

MoldDesign uses rules-based technology and parametric libraries to generate fully detailed 3-D solid models of the mold from the original part. The streamlined workflow and information exchange improve productivity and part quality, and reduce time to market.

Users choose components, such as plates, leader pins, bushings, and ejectors, from several industry-standard catalogs inside MoldDesign. The software then uses these components to generate the injection mold. The software also provides "push-button" tools for the design of the mold-cooling system and generates a complete bill of materials, including plates,

Did you know...
85.5% of survey engineers with CAD use the software for drafting.
Source: Design NewsMarket Beat survey.

inserts, component information, dimensions, and catalog numbers.

Because MoldDesign is part of the MechanicalSpaceTM user environment, project teams can perform modeling, detailing, structural analysis, kinematics, and manufacturing with a single engineering model.

Additional details...call (800) BENTLEY; e-mail: jen.mcwilliams@bentley.com; visit http://www.bentley.com


FEATURED PRODUCT

Software takes CAD to new speeds

A substantial increase in overall program performance and numerous time-saving enhancements highlight Autodesk's newest release--AutoCAD R14. The company says the new software is faster than both R13 for Windows and R12 for DOS.

The package boasts an improved graphics pipeline that uses less memory in loading files, and several productivity tools designed to save time. Among them: AutoSnapTM, which helps locate commonly used geometry during drafting, and tools for managing layers. Native raster imaging makes it easier to reuse paper drawings as a basis for drafting.

Solid fills, photo-realistic rendering, display ordering, and enhanced support for TrueType text creation and display improve presentation-quality drawings.

Several new features make communication and sharing designs easier. For instance, R14 includes reference file capabilities such as polygonal clipping and layer filtering. The ability to publish and access designs over the Web also is integrated into R14, along with single-click access to the AutoCAD support page on the Web.

Customization has improved through the use of ActiveX automation, which provides access to AutoCAD's core object and method set via Visual Basic. Meanwhile, features such as a network installation wizard, network license manager, multiple user profiles, and batch plotting ease the setup of R14 on a CAD network.

For more information call (415) 507-5000, visit http://www.autodesk.com


3-D interface speeds Rolls-Royce designs

Bath, England--The Rolls-Royce Industrial Power Group (IPG) wants to move analysis earlier into the design process to reduce time-to-market. Allowing engineers to quickly check stress values during product development would eliminate analysis backups and cut turnaround time. To achieve this goal, IPG asked ANSYS (Canonsburg, PA) to develop an interface that links the ANSYS finite-element package to Computervision's CADDS 5 modeler.

"If we can get the designer more involved in the stress side of things we are going to save a fair bit of time in the product development process," says John Rang, business systems specialist with IPG.

Ultimately, engineers will use ANSYS to verify whether stresses fall within certain high and low values. If the stress values produced exceed the predefined limits, the design will be moved to analysis. However, Rang says, "We have to get the designers involved in doing quick health checks on products as an intrinsic part of the CAE process."

One of the first groups to use the integrated CADDS 5 and ANSYS application is Clarke Chapman Marine Ltd. The Rolls-Royce IPG company makes marine deck equipment such as winches and cranes.

Clarke engineers design this equipment primarily in 2-D using Medusa software from Computervision. Once a design is complete and the drawings made, analysis is done in ANSYS. Now, designs are evaluated primarily with elastic analysis under pressure and loads, although some nonlinear buckling analysis is done. Since this type of analysis works best in 3-D, the full 3-D model is recreated within ANSYS, a time-consuming process.

The company hopes to speed design time by having only a single entry point for the 3-D model--the design stage. "We should save a third to half the time we spend currently developing the finite-element model, perhaps more," says Syd Addison, project manager at Clarke. This extra time might not decrease time-to-market, but Addison believes it will allow engineers to explore more design options.


FEATURED PRODUCT

Solid Edge 3.5 enters new CAD territory

Office 97-compatible, Solid EdgeTM Version 3.5 from Intergraph (Huntsville, AL) features the ability to model sheet-metal parts. Flat pattern, draft, and assembly capabilities are now included, along with tab, flange, contour flange, and break corner tools.

New rendering capabilities include colored lights, anti-alias options, reflections, textures, background images, and shadows.

Solid Edge's Pathfinder navigation tool makes it easier to manage assembly relationships. An assembly layout environment provides a more intuitive top-down design approach, and 'swept' and 'lofted' feature commands enable engineers to model more complex part geometries. The software also produces CGM files that can be viewed with popular Internet browsers, permitting users to share design data over the Internet and an intranet.

Also of note: support for "from scratch" 2-D geometry creation and mechanical-specific drawing composition, dimensioning, and annotation tools. This enables engineers to create a design in 3-D and detail the work in 2-D; 2-D geometry added to the drawing is associative to the drawing view from the 3-D model.

For more information on Solid Edge 3.5, visit http://www.intergraph.com


Products to watch

CAD for NT

CADDS(r) 5 parametric solid modeling software is now available for Windows NT(r). Compatible with UNIX-based CADDS 5, this software features an easy-to-use, object-based 3-D sketcher and parametric modeling enhancements in filleting, shelling, draft angles, history editing, and feature suppression. The software works with all Intel Pentium and Digital Alpha-based NT computers.

Computervision Corp., 100 Crosby Dr., Bedford, MA 01730, FAX (617) 275-2670.

Test-drive CAD CD

Toolbox products for AutoCAD and the Autodesk Mechanical Desktop are available for a 30-day test drive. A CD includes Toolbox for 2-D mechanical design and drafting with AutoCAD, Toolbox Professional for 3-D mechanical design and drafting with the Autodesk Mechanical Desktop, Toolbox/SM for solid sheet metal unfolding with the Mechanical Desktop or AutoCAD R13, and Toolbox/WD for ladder diagram design and drafting with AutoCAD.

CIMLOGIC Inc., 2 Wellman Ave., Nashua, NH 03060, FAX (603) 595-0381.

CAD

MiniCAD 7 is a full 32-bit cross-platform application for both Macintosh and PC systems. Solids modeling functionality allows for the union, difference, and intersection of 3-D shapes. Other features include 2-D enhancements, and the Smart Cursor, which allows for precise alignment by displaying where the cursor is in relation to the drawing. MiniCAD 7 supports Apple's QuickDraw 3-D rendering technology and associated plug-ins.

Diehl Graphsoft Inc., 10270 Old Columbia Rd., Columbia, MD 21046, FAX (410) 290-8050.

Viewing software

SolidView 2.1 lets anyone who has access to a Windows PC not only view designs, but measure and add annotations to communicate design issues. Solid View uses STL files generated from CAD systems and can import VRML data. Its publishing feature enables users to send a free viewer along with their designs, allowing communication with organizations that do not have Solid View. Users can also view 3-D face information in DXF format, and OBJ files generated from various concept modeling systems.

Solid Concepts, 28231 Avenue Crocker, Unit 110, Valencia, CA 91355, FAX (805) 257-9311.

Cost estimation

SEER-DFM 3.0 is a " part and process cost designer." Once the user identifies part, assembly, and manufacturing parameters, the software indicates the required process time and materials, and generates the unit costs for any operation. SEER-DFM can evaluate and compare design, material, and process alternatives.

G.A. SEER Technologies, 100 N. Sepulveda Blvd., Suite 1801, El Segundo, CA 90245, FAX (310) 414-3220.

Analysis software

Accupak/PE combines kinematics, rigid/flexible body dyamics, and non-linear stress analysis in a single package. The software simultaneously analyzes mechanical events involving large-deformation, non-linear material properties, kinematic motion, forces caused by motion, and stress prediction. Features include: live monitoring, optional bandwidth, and automatic contact/bounce.

Algor Inc., 150 Beta Dr., Pittsburgh, PA 15238; FAX: (412) 967-2781.

On CD: Analysis Opportunities

Leading software technologists present their views on trends and opportunities for computer-aided engineering (CAE) analysis on the CAE Round Table Forum CD. The disk includes sample solutions to a wide range of industrial design challenges, such as a metal profile rolling simulation. Several industries are represented, including automotive, chemical processing, consumer products, power generation, and metals processing. The CAE examples vary in application complexity, covering nonlinear response, structural dynamics, computational fluid dynamics, and design optimization.

Silicon Graphics Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94043.

Is there an electric car in your future?

Is there an electric car in your future?

No, there will not be an electric car in every garage in the near future. However, based on a few advanced prototype models about to enter the marketplace, EVs seem likely to shed their overgrown golf cart persona and be seen as practical--even fun--transportation.

In the early 2000s--a manufacturing eye blink away--improved batteries will double vehicle range, recharge times will drop, and auto engineers will better understand the nuances of EV design. And the forces of mass production will drive down prices to the point where, when looking for a new car, you'll check out an EV without recoiling from sticker shock.

Why the optimistic forecast? Test drives conducted by Design News editors of the General Motors EV1, Toyota RAV4-EV, and Solectria's Sunrise, Force, and E-10. The latter two have been on the market for a few years. So it's really up to the advanced prototypes to change the buying public's impression of EVs being too high-priced, too short-ranged, and too inconvenient to "refuel."

Still, it seems unlikely that public approval alone will drive buyers to EV show rooms. A possible push for EV sales could come from looming government mandates in several states that require a percentage of the vehicles sold there to be zero emission models. Tax incentives might help, too. So the question remains: are these EVs "real" cars, or poseurs meant to satisfy the bureaucracy? Let's find out.


EV1:GM's current alternative

by Michael Puttre Associate Editor

I came to the GM Proving Grounds with charitable thoughts. The only electric vehicle I had ever driven was the golf cart I almost flipped working summers at a county club.

GM's EV1 is no golf cart.

There are a dozen or so EV1s on hand, including the yellow Impact (an ominous name) experimental model that set the electric car speed record of 185 mph. None of us are allowed to drive that one. My test car is a red preproduction model that is nearly identical to the EV1s that hit selected Saturn showrooms late last year.

It does have those unsightly rear wheel skirts. I am told those are for streamlining and provide an additional 3/4 mile of range per charge. It doesn't have an external radio antenna. That buys 1/6 mile. The aft end is rather more pinched than I like. Better aerodynamics, the engineers explain.

Everything about the EV1 is designed to overcome the limitations of current battery technology. The EV1's steering wheel and seat frames consist of magnesium and are said to be the lightest in the industry. The aluminum body frame is fabricated using a weld-bond adhesive process to make it stiff and light. But those lead-acid batteries--all 27 of 'em--weigh 1,170 lbs.

Once in the driver's seat, the EV1 presents an assortment of unfamiliar controls, plus that new car smell. My driving partner is a fellow journalist. As the EV1 only has two seats (and very spacious seats they are, with useful trunk room to boot), we do not have any GM corporate types with us to tell us how to drive. GM tries to exercise some control with an electric car driver efficiency contest, but we came in near to last, so we won't dwell on that point.

The EV1 does not require a key. Instead, I punch a code into a keypad and we're on-line. The car makes a sci-fi humming noise when accelerating and braking that is not unpleasant. The absence of firing pistons and changing gear harmonics takes some getting used to. The EV1's regenerative braking system reclaims some energy spent slowing down and gives it back to the batteries. In addition, there is a button on the shifting column that, when pressed while coasting, is supposed to do the same thing.

I whisper us around GM's Truck Loop test track, hang a left at the Pinkerton security guy, and drive out into the real world. The lack of engine noise means you must pay attention to the speedometer. A minor but persistent annoyance: the high-tech steering wheel is too small. I feel like I'm at the wheel of Barbie's 'Vette--until I step on the accelerator (I almost said gas pedal). I have no problem attaining whatever speed I want whenever I want it.

After changing seats, my partner makes this point utterly clear when some bloke in a blue Corsica wants to see what we we're made of at a red light. You can't rev the engine of an electric car, but we quietly get respect. I watch the Corsica recede smoothly in my rear-view mirror.

On the highway we get up past 80 mph--until we hit a construction zone. Unfortunately, we use up power in stop-and-go traffic at nearly the same rate as we do at speed. We want smokes but discover to our horror that the EV1 is not equipped with a cigarette lighter. Consider: We are sitting on a 312V electrical system but we can't get a light. So we pass the time fielding questions from curious drivers.

"What the hell is that?" yells a trucker from on high. "An electric car!" I yell back over the grumble of his idling diesel. The trucker grins and gets on his CB, presumably to alert comrades to watch out for us.

"How much do they cost?" asks a beefy, red-haired guy in a green Intrepid, visibly impressed. "About $35,000," I tell him. "Whoa!" he blanches. "I'd rather buy a gas car."

And therein lies the chief barrier to the widespread acceptance of electric cars. The EV1 performs like a dream: it's quick, fast, responsive, stable, and quiet. But it costs too much.

To be fair, GM invested $350 million in the technology required to make the EV1 happen. They're not just going to give them away. Even with an attractive lease program, GM does not expect to see a profit on this particular model. Frank Schweibold, director of finance and strategic planning for GM's advanced technology vehicles group, says the company hopes to reap its rewards on future offerings.

Next, I take a couple of laps around the Truck Loop, this time in a silver-blue EV1. In the passenger seat is Jim Ellis, engineering director for the EV1 program. The cup holder holds my soda firmly. My electric window is down as efficiency is no longer an issue. I palm the wheel and thoroughly enjoy myself, although I regret not having my Metallica album on hand to try out the standard-issue CD player. Ellis takes delight in thumbnailing the six-year story of EV1's development.

"This is a great car," I acknowledge when relinquishing the EV1 to GM. "I wish I could afford one." Ellis smiles sympathetically: "Back to the smelly, noisy world of internal combustion engines."


RAV4-EV:A Toyota with a mission

by Mark A. Gottschalk Western Technical Editor

Open the door of Toyota's RAV4-EV, slide behind the wheel, and you'll find yourself staring at the interior of...a RAV4, what did you expect? Almost boringly normal in appearance, it shatters the futuristic image of electric cars shaped like eggs. And that's the point. If it looks like a normal car and feels like a normal car, perhaps it is a normal car.

Closer study reveals several subtle EV-specific features. For one, the dash includes two voltage meters. A standard meter displays the status of the conventional lead-acid battery that powers the headlights, dome light, radio, etc. A second meter tracks the instantaneous output from the 24 12V nickel-metal hydride (NiMH) batteries that provide motive power. Next to the instantaneous voltage gauge lies a charge-level indicator that looks and acts very much like a conventional fuel gauge.

Turn the key to "start" and, of course, nothing happens, save for a green "ready" light that appears on the dash. Move the floor-mounted gear selector to drive, and you're off.

I pull out of the parking lot of Southern California Edison--the utility company that kindly arranged my test drive--and turn onto a busy four-lane road towards SCE's Electric Vehicle Technical Center, 25 miles away. Acceleration easily compares to a normal compact car, with the only sounds being a slight whir of the 45-kW (60 hp) motor, wind, tires, and suspension. The EV's extra 400+ lbs of weight--compared to the gas model--isn't noticeable.

Pull your foot off the pedal and the car coasts freely. Shifting to a special "B" mode from "D" activates the regenerative braking, which proves to be a joy around town. Accelerating and decelerating in traffic--even slowing for lights--could be accomplished almost entirely with the throttle. At a stop, the motor stays lightly engaged, providing a "creep" effect similar to that of a standard car with automatic transmission.

The air conditioner ices the interior in minutes, dispelling the notion that electric cars will offer reduced comfort. It does, however, lop 10-20% off the car's respectable 118-mile range. I obtain a range of 85-90 miles with the A/C blasting constantly. Based on a heat pump, the system produces warm air for the winter as well. Heated seats, windshield, and rear-window defogger compensate for the gasoline version's natural abundance of thermal energy.

On the freeway, the RAV4-EV easily keeps with traffic and almost effortlessly reached its electronically limited 79 mph top speed. A button on the shift selector lets the driver change from power to economy mode. The latter noticeably reduces current drain, but couldn't maintain speed on some steep highway grades.

The EV chops annoyingly over seams in the concrete freeway. However, this might be the result of the SUV's sporty suspension and special low-rolling-resistance tires, and not an inherent quality of the electric drivetrain.

Due to the high demand for tests of this prototype, I didn't get the opportunity to live with the vehicle. Had I, I'd have found the 6-8 hour charging process, which seems as simple as plug-it-in-and-leave, a bit more daunting. Most buyers will need an electrician to add a special 220V, 40-amp circuit to their garage, at a cost of $500-$1,000, says SCE.

The charge cord terminates in a handle that resembles a gas nozzle. Two flip-up doors on the right front fender conceal conductive plugs for normal and rapid charging. A timer system in the center console lets the user start recharging immediately or schedule it during off-peak hours. Placing these controls right at the socket would prevent having to get in and out of the car twice every time you recharge.

A price hasn't been announced. Toyota plans to lease RAV4-EVs in 1997-98.


The drivingforce in production EVs

by Michael Puttre Associate Editor

Solectria Corp., Wilmington, MA, has a big pile of mufflers out in back of its corporate office/research center/manufacturing facility. Compact sedans and small pickups are lined up along the side with extension cords plugged in where the gas caps should be. Out front, signs read, "EV Parking Only." All others will be what--zapped?

Solectria founder and CEO James Worden says he has never owned a gas-powered car in his life. Worden, MIT Class of '89, built himself an electric car in high school, won the state science fair with it, and is also his company's director of research and development. Solectria might be considered a big garage hobby shop: a copper coil battery & light bulb experiment to the nth power--except it sells cars, over 160 of them to date. In fact, Solectria manages to sell just enough cars, attract just enough investment capital, and get just enough government grants to keep the mufflers piling up out back.

Solectria's primary EV is the Force, a conversion from a gas-powered car. OK, it's a Geo Metro. I own a VW Fox, which seems like a King Tiger by comparison. But there are lots of Metros out there. Karl Thidemann, Solectria's marketing manager, informs me that Metros are manufactured all over the world under many different guises--and each one could be reckoned an aspiring Force. Thus, Solectria's design could be applied to any number of overseas markets.

The Metro, as it's name implies, is a useful enough four-seater about town. The Force inherits this quality. I get behind the wheel with Thidemann riding shotgun and consider that two (small) friends could have come along, too. By now, I'm an EV veteran, so I don't get all excited by the fact the Force doesn't make any noise when I turn the key.

The Force has a box with a knob on it where the stick shift had been reminiscent of a model train control unit. There are three power level settings going forward, plus neutral and reverse settings. I turn the knob to high, step on the accelerator, and whine out of Solectria's lot into an industrial park.

While driving, the car makes a buzzy sound I don't like very much at first but quickly come to ignore. The accelerator is very soft, too. Basically, I alternate between flooring it and coasting to maintain speed. The regenerative braking system, however, is a very comfortable way to slow down. It pays, too. I enjoy watching the LCD display show me how much charge I'm putting back into the lead-acid batteries as I roll up to stop signs.

Out on busy Route 128, I can go as fast as I would want to for local distances. The Force has a rated top speed of 75 mph and I approach that. The usage meter chides me though. It reels off ever-increasing numbers like one of those real-time national debt displays. The $35,000 Force would carry me an average of 50 miles between charges. I could opt for NiMH batteries and double that range--provided I want to spend $75,000. It takes a special person to plunk down that much for an electro-Metro.

Still, Solectria's vehicles can be recharged overnight from 110V outlets. The reduced maintenance and fueling costs for electric vehicles might compensate for the large initial outlay: Solectria hasn't done any long-term ownership studies. A number of utilities and nearby Hanscom Air Force Base have fleets of Solectria EVs, albeit of the lead-acid variety.

Many fleet buyers opt for the E-10 pickup truck, a conversion from a Chevy S-10. The E-10 features light pickup loading characteristics and significantly more power than the Force. I immediately recognize this when I drive the E-10. It rides higher, the acceleration is brisker, and it is a lot quieter than the Force. Since there is more room for batteries under the flatbed, the EV pickup claims a range of 60 miles at 45 mph. It costs $50,000.

Solectria's technological tour de force is the Sunrise, winner of the 1996 Tour de Sol endurance race sponsored by the Northeast Sustainable Energy Association, Greenfield, MA. The EV, an advanced prototype of a vehicle scheduled to go into production in less than two years, managed a run of 375 miles before its NiMH batteries had to be recharged. The record for a production vehicle, by the way, is 249 miles. This was established during the 1997 Tour de Sol by a NiMH-equipped Force.

At first glance, the Sunrise is an aerodynamic cousin to GM's EV1. However, the composite body does not use a lick of metal structurally, making it a lighter. The workshop where Sunrise prototypes are assembled resembles a boat shop. In fact, the fiberglass-like body panels are outsourced to a sailboat maker.

The Sunrise seats four comfortably with ample surplus legroom for the driver and front passenger. The car has a vast expanse of dashboard for keeping great quantities of the sundry items that tend to accumulate in cars. In fact, there is almost too much room up there (imagine that).

I go to roll up the window (standard operating procedure for aerodynamics-conscious EV drivers) but find no button or crank. Windows, when carried, are held in place by Velcro. This will not be so in the production model, I am assured. I am offered a window, but I decline.

The power control box is replaced by a circular knob on the vertical dash, rather like the cycle knob on some washing machines. I set the Sunrise to high and hit the road. This accelerator is squishy, too, and seems to be a Solectria trade-mark. However, Sunrise is very well behaved acoustically.

Out on Route 128, Sunrise's aerodynamics provide a smooth ride at all speeds. The car sports a bright yellow futuristic look and has all sorts of racing-style corporate sponsorship stickers on it. I check out other drivers on the highway, expecting to receive admiring gazes. I don't get so much as a glance. The locals must be used to seeing EVs in their midst.

So might we all, one day.

Basic philosophy yields success with basic parts

Basic philosophy yields success with basic parts

Danboro, PA--Good technology and forward-thinking management. Relying on those basic principles, Penn Engineering & Manufacturing Corp. has moved to the top ranks of the fastener industry.

From modest beginnings more than 50 years ago, the company has expanded some 20 times since the early 1950s, including its latest and largest addition of 42,000 sq ft. In the past five years alone, the fastener manufacturer has doubled in size from a $70 to a $140 million business.

Making the right connection. In 1942, when RCA switched from using thick cast-metal sections to thin sheet metal for its military electronics enclosures, the company faced a serious problem--how to provide reliable threads in this new material for component attachment. K.A. Swanstrom solved the problem by developing the self-clinching nut.

Swanstrom's design was simple: As the fastener is pressed into a punched hole, the sheet material actually moves or "cold flows" into an undercut below the fastener head, locking the device securely into the sheet. The result is a reliable threaded insert that provides a means of assembling--and disassembling when necessary--other components with the thin sheet metal.

This self-clinching technology was Swanstrom's foundation for Penn Engineering. Today, the initial concept has expanded into 28 families of products comprising 12,000 different items, including threaded inserts for plastics and broaching fasteners. Penn Engineering has distributors in 40 countries around the world. And PEM(R) fasteners are in everything from computers, instrumentation, and medical equipment to garage-door openers, wiper blades, and airbags.

"We use the same basic technology as 50-plus years ago, and no one has come up with something that can do better," says Leon Attarian, manager of marketing information and communication at Penn Engineering, "And, we discover new applications all the time."

Fastener appeal. Chairman, CEO, president, and son of the company's founder, Kenneth A. Swanstrom attributes a great deal of Penn Engineering's success to its comprehensive catalog and readily available stock.

"Engineers generally don't like special designs because they mean long lead times and typically high costs," says Swanstrom. "We can lead a customer to a standard proprietary design stocked in fairly good quantities so he doesn't have to worry about designing a special product."

But don't be mislead: Penn Engineering hasn't abandoned the idea of special designs. The company still works with customers to develop such products if one of its standard items doesn't quite fit the bill. In fact, each of Penn Engineering's products has its roots in custom design. "We don't design our product lines in closets," notes Swanstrom. "They're all the result of requirements we've found common among our customers over the years."

Penn Engineering also manufactures automatic and manual installation presses for its fasteners, and provides inserts for use in thermoplastic materials as well.

One measure of the company's success is its production schedule. The plant has been operating two shifts 60 hours per week for the past three years just to keep up with demand for its products. That means Penn machines have been pumping out fasteners 120 hours a week for three years. At a rate of up to 1,000 per hour, that's about two billion fasteners per year. The company has even experienced problems with availability of cases for shipping its products.

Home-grown success. Even with Penn Engineering's range of products and services, Swanstrom acknowledges that the true source of the company's accomplishments is its employees. "Everyone is dedicated to seeing the company survive and flourish, and change as change is necessary," he says. "We treat our employees as people, not numbers, because it's the people that really make a difference."

With that thought in mind, Swanstrom tries hard to create and maintain a family environment at Penn Engineering. Pizza days and company picnics occur regularly. The company newsletter, with a special column written by Swanstrom, keeps current employees and retirees informed. And don't forget the annual Christmas party, to which all retirees are invited. "Our retirees are an important part of why Penn Engineering is where it is."

Proof positive. Penn Engineering backs up its commitment to its employees in the training benefits the company provides, including technical training, an apprentice program, and tuition reimbursement for both technical and general degrees. The profit-sharing plan, according to Swanstrom, makes employees feel directly responsible for what the company is doing to make money, and for seeing that the company succeeds. "Each person takes personal pride in that," he says.

The family atmosphere, good benefits, and plenty of extra work all add up to a pretty good deal says Curt Martin, supervisor of screw-machine operations at Penn Engineering. And though he admits a lot has changed over his 30-year career at the company, Martin isn't taking his job there for granted. "Anyone would be foolish to think they could go somewhere else and find a situation as good as this one," he says.

Judging from the employment history at the company, plenty of others agree. Of the 1,320 employees at Penn Engineering, almost 10%--107 people--have worked there more than 15 years. And 71 of those 107 have been with Penn Engineering more than 20 years.

A moral presence. Penn Engineering's goodwill doesn't stop with its employees. It extends outside the company walls and into the surrounding community. In addition to supporting a local technical school, Penn Engineering works with an area elementary school to provide funding for special school projects. The company also volunteers speakers and sponsors a school science fair--an event of which Swanstrom seems especially proud. "I made sure it was not a contest," says Swanstrom. "Everybody wins because all the children do their best."

Educational involvement isn't Penn Engineering's only step toward contributing to life in the area. The company makes an effort to be environmentally conscious, and has even gone so far as to clean up its own mistakes. At one time, Penn Engineering had 13 below-grade tanks containing various process liquids. The company removed the units and set up an above-ground tank farm well before being asked to do it. Penn Engineering also converted from using a chemical wash to using an aqueous washing machine. Though the company invested considerable funds in the project, Swanstrom prefers knowing the company isn't polluting the environment.

For all of Penn Engineering's success and involvement, it still remains a fairly low-key company. If you were to stop in the area and ask directions to their site, Swanstrom and Attarian joke, people probably wouldn't be able to help you. That seems unusual since Penn has been in this location since 1952, but Swanstrom isn't concerned.

"I think I just let awareness grow in a normal manner as opposed to putting on some big bash. Certainly working with the local schools gives us community awareness in areas we think are important. But just to make a lot of noise for the sake of making noise, I don't think that's worth anything," says Swanstrom.

When asked about the future of Penn Engineering, Swanstrom's answer seems simple. "I want us to be here many many years from now," he says. "I'd like to make sure everybody can retire from here." If Penn Engineering's record so far is any indication, Swanstrom may just get his wish.

Design to survive

Design to survive

An underwater explosion, repeated jolts from a 100,000-lb excavator, a helicopter crash, 30-ft drops to a steel surface. While these may sound like stunts from the latest Hollywood action film, they're actually a short list of real situations presented to engineers who had to design products to survive them.

No special effects would do. For assistance, each turned to a tool that was at one time the province of engineers bearing a masters degree or Ph.D.--finite element analysis (FEA).

Extreme environments lend themselves well to simulation. While computer modeling certainly presents its own challenges, recreating actual bangs, bashes, strains, and bombs in controlled tests--and capturing data from them--can be terribly expensive, time consuming, possibly dangerous, and far less versatile.

However, a variety of FEA tools are available to the designer, each with its own strengths. And while careful application is still required to get meaningful results, the tools have become far more accessible to mainstream engineers than ever.

What follows is a look at a diverse range of products and systems developed to survive unusual situations. While many aren't ordinary design problems, their solutions can spawn ideas that find application in more everyday products--the way auto racing improves production cars. Think of them as lessons in survivability.

Bomb-proof ball valve

The ocean presents a uniquely hostile environment for engineered equipment. And the boats that ply beneath her waves, the submarines, are some of the most robustly built and secret of all military vessels.

Fitted to each sub are numerous ball valves used to regulate such critical systems as ballast and trim. Specialty & Ball Valve Engineering (SBVE), Tustin, CA, has supplied such valves to the Navy for more than 25 years, and under several different corporate identities.

Recently, the company applied extensive finite element analysis to design special versions of its DynaflowTM valves for a classified, manned underwater vehicle. The customer asked that the valves not only be as light as possible, but also able to withstand sudden, high-energy pressure spikes without failing.

The source of these spikes? "Submarines can get shot at," says Harry Buehrle, the company's marketing director, "and our valve would see the pulse from the resulting explosion." The ballast tanks are tied directly to the subs' external environment, and any pressure surges would pass like shock waves through the ball valves.

By using FEA, engineers eliminated the need to physically test for the dynamic shock criteria, saving substantial time and money. Computer modeling also helped them trim 4-8 lbs each on the more than 40 valves fitted to the boat.

DynaflowTM ball valves meet the Navy's most stringent criteria, Level 1/Subsafe. Standard models come in five sizes weighing from 12 to 250 lbs, and with orifices from 0.5 to 2.3 inches. Materials include stainless steel, Monel(R), titanium, and Inconel(R).

While designed primarily to handle gases, the valves can regulate fluids as well. All offer zero leakage at up to 6,000 psi and top loading of the internal components for easy maintenance.

Consulting engineer Zach Pursell of Mechanical Analysis & Design Consultants (MADC), Oceanside, CA, performed the finite element modeling of the custom "lightweight" valve using MARC Analysis' (Palo Alto, CA) FEA code. "The biggest questions we had to answer were, would the valve body survive the shock impulse?" he says, "and, if so, what about the seals and internal components?" While weight was also a design driver, the dynamic impulse condition proved to be about five times more important in determining the valve's final configuration.

Pursell modeled each valve part separately and used MARC's adept handling of nonlinearities and contact to analyze interaction between components. "There really is no other code on the market that will model contacting bodies like MARC will," he says.

Limb lopper takes abuse

Ed Danzer understands a thing or two about designing machines to survive rugged environments. His company, Danzco, produces--among other things--the PT-20 series of delimbers for the logging industry that, like a kid popping tops off dandelions, can strip branches from a felled tree in seconds.

The portable machines consist of a heavy steel base with bladed legs that plant into the earth for stability. A small on board diesel engine powers a 1,000-psi hydraulic circuit that drives two opposing semicircular steel knives via 2.5-inch-bore cylinders.

Cut trees are pulled between the knives by a crane-like excavator or tractor. The knives clamp the tree trunk with 500 to 1,000 lbs contact force, trimming the limbs as close to the bark as possible. The trees can range from two to 20 inches in diameter, and Danzer has seen customers delimb up to 250 logs in an hour.

He's also seen them inadvertently tip over a 7,000-plus-lb delimber by using it a little too vigorously. And he's seen the 3/8-inch-thick plate motor mounts bend when an excavator operator picks up and drops a machine in a new location like a child's tinker toy.

But what drove him to using FEA was when users began experiencing bent knives. The two-inch-thick knife arms made of A-36 steel plate measure six inches wide at the shaft. They are designed to take 15,000-20,000 lbs of force. "But to eliminate warranty issues, we started using finite element modeling to figure out what the forces and stresses really were," Danzer says.

He leverages a combination of PC-based software tools: SolidWorks 97 (SolidWorks Corp., Concord, MA) for CAD design; Working Model (Knowledge Revolution, San Mateo, CA) for kinematics; and COSMOS/Works (Structural Research & Analysis Corp., Los Angeles, CA) for FEA. All but six hoses of the delimber's 1,200-component assembly are completely solid modeled. The design pushes the limits of the software and hardware--an Intel Pentium 166-MHz PC and Digital Equipment 433 workstation.

Though supplied by different vendors, the programs work well together. "Instead of having to know how to create geometry in three packages, I only have to know one--SolidWorks," he says. "I can click on motion and throw the model into Working Model and get the forces, and then do the same thing for finite element modeling."

Working Model helps Danzer determine the magnitude and direction of the forces being generated. "One of the toughest parts is knowing what values to put in the FEA and where to place them," he says. With the delimber, forces on the knives actually exceeded 30,000 lbs. By changing the material to stronger A-514 plate, he solved the bending problem without having to alter the knives' geometry.

Not one to rest, Danzer is developing what he says is the industry's first Cut, Fall & Load grapple (CFL). It's a single system that can reach out and grab the tree, cut it off, pull it through the delimber, buck it to length, and load it on the truck--replacing the function of four machines.

Again, the possibility of rough usage is playing a key role in the design, which began prototype testing in May. "If they attach the grapple to a 100,000-lb excavator and start pulling stumps, we've documented pressure spikes in the hydraulic cylinders of 20,000 psi," he says. "The cylinder pins are 2.5-inch, 4140 induction-hardened steel, and I've seen them sheared off." Building the CFL to survive, it seems, is another job for FEA.

Helicopter airbag softens blow

To promote a high-tech image, automobile manufacturers often allude to their use of "space age" technology. But if engineers at Simula (Phoenix, AZ) have their way, military helicopters might soon benefit from an safety system first introduced in the family car: the airbag.

The project stems from an Army Small Business Innovation Research (SBIR) program dating to the early 1990s, but has been expanded to other military and civilian aviation organizations. Its ultimate goal: to develop a cockpit airbag system, including the necessary sensors, logic, firing systems, bag configurations, and packaging, a helicopter might need. Target rotorcraft include the AH-64 Apache, UH-60 Blackhawk, and RAH-66 Comanche.

Helicopter crews should especially benefit from airbags. The cockpits are more snug than automobile interiors and populated by hard, closely positioned consoles and controls that can strike the head and upper torso during a crash. Accidents usually involve large vertical forces. And though a special "stroking" seat significantly reduces spinal injury, it also brings the crew closer to secondary strike hazards. Many crashes involve lateral motion for which the restraint harness offers little protection.

To better understand and predict body kinematics, engineers turned to finite element modeling. "Our main goal was to see if it was possible to use analysis tools to examine how the occupant would react to a deploying airbag in a crash situation," says David Furey, analytical engineer at Simula. "We want to duplicate in the computer all the military-defined crash situations and design an airbag that would protect during them." A second goal: to see if computer simulation could ultimately reduce the number of tests required.

Furey used MacNeal Schwendler's (Los Angeles, CA) MSC DYTRAN for the analysis and PATRAN for pre- and post-processing. He ran it on a Silicon Graphics (Mountain View, CA) Power Challenge with four R8000 CPUs. The computer mannequins were defined by ATB (Articulated Total Body), a public-domain, rigid-body model maintained by Wright Patterson AFB that links well with DYTRAN.

Furey modeled complete cockpit interiors with two occupants and three airbags--front and two side bags--and simulated complete crashes from zero to about 120 msec with a variety of firing times for the bags. Simulated vertical velocities ranged from about 30-42 ft/sec, resulting in as much as 45g peak deceleration for the cockpit.

The airbags were modeled as triangular finite-element membrane elements. Due to space constraints in the cockpit, the bags tend to be unusual shapes, and the biggest challenge was simulating the unfolding action. The problem is compounded by the possibility of a partially deployed airbag striking an out-of-position crew member.

"I have to accurately depict the bag unfolding as it hits the occupant, and that is very difficult to do," says Furey. "DYTRAN was the only code we looked at that could model the complex geometry of the bag as folded and model the contact of the folds as it deployed."

For those things DYTRAN couldn't do Furey turned to MSC. Several times the company made quick changes to the DYTRAN code to accommodate special requests.

Should further tests prove the accuracy of the simulations, an opportunity exists of using them to save money and help accelerate future designs.

Shipping container survives falls

Many times shipping containers have to survive unusual events to protect their cargo, none more so than the new AT400-A. Spawned from a joint Department of Energy project, the cylindrical container--looking roughly like a 30-gal drum--was developed for the transport and storage of nuclear components, such as the plutonium "pit" that forms the heart of an atomic bomb.

Various aspects of the AT400-A's design were distributed among several DOE institutions. The structural development fell to Lawrence Livermore National Laboratory (LLNL), and engineers there made significant use of DYNA 3D, a finite element code developed at the lab that is particularly adept at high-strain-rate, non-linear, large-deformation events.

Specifications called for the container and its contents to survive a 30-ft fall onto a hard surface. "The anticipated accidents are with ground transport," says Peter Raboin, methods development group leader at LLNL. "We had to design it to absorb a certain quantity of energy over a certain displacement."

The container's outer layer is designed to mitigate fire. Inside are structural elements for impact and shock. Using DYNA 3D, engineers designed a suspension structure towards one end of the can consisting of a "C" channel running around the circumference of the container. Suspended from the flange is a fixture, like a chuck, that holds the nuclear component.

The "C" channel was designed to distort and absorb energy during an impact. "If it falls on one end of the can the flange compresses, and if it falls on the other it extends," Raboin explains.

Less simply, engineers purposely added sharp corners to the flanges' attachment bolt holes to actually promote tearing of the metal. "This nearly doubled the energy that the flange alone could absorb," Raboin adds. Lastly, to fine tune the structure for the desired deceleration values, the engineers created special shims.

The extremely complex DYNA 3D models contained about 70,000 nodes and 27 contact surfaces. They took as much as 140 hours to run on a Cray T3D. "It was frustrating." states Raboin. "The analysts couldn't keep up with the drafting designers."

Part way through the program, however, engineers gained access to the Lab's Meiko (San Francisco, CA) CS-2 massively parallel processing (MPP) computer. As a result, calculations took less than 10 hours, and Raboin notes that they gained the capability of performing full systems analysis rather than just individual components.

In the race against the drafters, the analysts caught up and actually pulled ahead. Says Raboin, "It was the first project I'd been involved in where the analysis had an impact on the design before it was finished."

Portable scanners take a beating

Mitch Maiman has heard about users of his company's barcode scanners who pay so little attention to the product that they casually dangle them off the side of a moving forklift, banging them into objects while driving along. That's exactly how he likes it.

"What differentiates us from our competitors is our ability to develop a rugged product that can take the shocks and falls that are part of our customers' world," he explains. "They should be able to use it without worrying about dropping it."

Maiman is the Senior Director of Scanner Product Engineering for Symbol Technologies (Holtsville, NY), a company that manufactures portable data-capture terminals, wireless data communications equipment, and barcode scanners. These ubiquitous devices are used daily by express-package delivery personnel, rental-car agents, and warehouse inventory checkers.

At the heart of most of these products (and many others) is Symbol's SE-1200 family of scan engines. Though comprised of seemingly delicate lasers, oscillating mirrors, and electronics, they'll withstand 2,000g shock pulses.

To ensure the products survive, Symbol engineers make extensive use of finite element analysis. Product definition is done with Structural Dynamics Research Corp. (Milford, OH) IDEAS software and finite-element analysis with ANSYS from ANSYS Inc. (Houston, PA).

SE-1200s generate a rapidly scanning line of light that, when pointed at a bar code, reflects back into the scanner to be interpreted. The scanning is generated by a patented mechanism that reflects a laser off an oscillating mirror. The mirror and a magnet are attached to a Mylar spring and driven at the assembly's resonance point. "A big use of the analysis is for the fatigue of the motor, which sees millions of oscillations, and for determining the natural frequency," says Maiman.

But shock analysis is an even bigger design driver. An example is the PPT 4600 series of portable pen terminals. Engineers were challenged to make the devices withstand repeated 2m falls to concrete. They also weigh just 1 kg and must remain affordable--ruling out exotic armor.

Compounding the problem, each terminal contains a glass LCD touch panel for which, Maiman notes, the manufacturers could supply virtually no mechanical data. "We had to reverse-engineer them," he says, "and characterize the displays ourselves."

These characterizations resulted in detailed FEA models of the LCDs used to accurately simulate real-world mechanical performance. Leveraging these tools, engineers designed a patent-pending frame within a frame to protect the display. An internal frame supports the LCD; it, in turn, is attached to an external frame formed of injection-molded plastic overmolded with rubber. "The computer modeling let us engineer the connection between the inner and outer frames to get the level of energy absorption we needed," Maiman explains.

Such attention to detail pays off in the end. "It's somewhat expensive to analyze everything; it costs money up front," says Maiman.


Cyber contacts

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ANSYS: www.ansys.com