The Best Products of 2004

When it comes to technical products, working design engineers really do know best. So for this year's Design News Best Products of the Year contest, we decided to put all the contenders up for a direct vote and ask our readers to be the only judges. This year's contest drew a record number of entries from vendors in five categories only an engineer could love—electronics, motion control, fluid power, software and hardware, and materials and joining. Here's a look at the winners:

Electronics Analog Control

Fewer Phone Wires Chipset reduces 20 or more wires to just three

To help engineers save critical space in cell phones, the Mobile Pixel Link (MPL) Interface and Chipset from National Semiconductor offers serial connections that substantially reduce wiring requirements. Phones that have Mpixel cameras, large color displays, or simply use clamshell configurations today rely on wide parallel interconnects for image sensors and displays. The MPL eliminates much of that wiring. "Wide parallel buses require 21 lines for displays. We reduce that to three wires," says Jim Schuessler, senior technical marketing manager for National Semiconductor's Portable Power Systems Group. Some competitive schemes reduce wide buses to around nine, which still takes more space than the serial link, he adds.

The MPL is based on a low power, low EMI physical layer, and straightforward serialization of legacy parallel interfaces. It uses current mode signaling instead of voltage mode techniques. "We need approximately half the power competitors use to push the signals," Schuessler says. That's about 5 mW per wire, he adds.

The connections have low impedance, so they have high immunity from signal coupling from power amps and other components. National is offering the technology as a standard for phones. As phones display more graphics and move higher resolution images, low power consumption and small size will force design engineers to focus more on connections to the displays, Schuessler says.
http://rbi.ims.ca/4388-650

Components, Hardware, Interconnect

These Ultracapacitors Give UPS a Quick Response Back-up power gains speed

Maxwell Technologies Inc. has unveiled a family of ultracapacitors designed to augment uninterruptible power supplies used in telecommunications, industrial, and medical applications. These Powercache ultracapacitor-based backup power modules provide quicker response and longer lifetimes than lead acid batteries without significant differences in lifetime expenses.

Aimed at applications that require a short-term bridge for long-term backup systems that take a while to ramp up, the ultracapacitors have much longer lifetimes than batteries. They often last 10 years, compared to three to four years for lead acid batteries. Though ultracapacitors have higher initial costs than lead acid batteries, their long lifetimes reduce replacement costs for batteries. "Ultracapacitors don't usually have to be replaced, so operators don't incur maintenance and disposal costs," says Maxwell Vice President Robert Tressler.

The Powercache backup systems, which fit into standard 4U rack mount housings, are seeing acceptance as an adjunct to fuel cell backup systems. Fuel cells run for long periods, but they have slow start-up times. "Companies that use fuel cells for long-term outages use ultracapacitors for the 20-30 sec it takes for the fuel cells to get ready," Tressler says.

The 48V modules come in two models, rated at 1.6 and 2.3 kW. They comply with Network Equipment Building System (NEBS) telecommunication standards.
http://rbi.ims.ca/4388-651

Digital Control/Embedded Computing

Controller Determines When Drivers Have Turned No more non-stop blinkers

Electronics have taken over many mechanical functions in cars and trucks, but the blinker mechanism remains a holdout. That could change if automakers adopt a system from tiny RLP Engineering.

The RLP solution, called IntelliTurn, employs sensors and controllers already on the vehicle to determine when to turn off blinkers, ending driving hazards that occur when drivers don't realize their blinkers are still on. "This system uses the wheel speed sensors of the antilock braking system, looking at differences between the right and left wheels to determine yaw and the degree of the turn," explains Richard Ponziani, company president.

The software, which can utilize an existing controller in the vehicle to keep costs down, watches the rotation differences, determining that turns are finished when the vehicle goes straight for a while. That works even in mild turns like Y junctions or lane changes, Ponziani says.

The system also eliminates instances when drivers at a full stop turn on the blinker, then turn the wheel slightly and turn it off. "This isn't looking at steering wheel movement, so you can move the wheel as far as it goes without resetting the blinker," Ponziani says.

Since there are no mechanical linkages to trip, blinkers can be operated by push buttons on the steering wheel so drivers don't have to take their hands off the wheel. The system also reduces wiring because it uses existing vehicle networks. OEMs can program the system to offer different features. For example, if a driver turns the blinker on and then doesn't turn, blinkers can be turned off after a predetermined distance.
http://rbi.ims.ca/4388-652

Power Management/Control

Power Watcher Modular power system speeds ATE systems

Monitoring power consumption becomes far simpler with Agilent Technologies' N6700, a modular power system designed for test and measurement applications. The compact, configurable power supply lets users provide a number of power inputs to devices being tested while also offering a digitizer that helps them monitor power usage.

The power system provides inputs that can be used in aerospace, peripherals, and consumer electronics, helping design engineers understand how the system responds in operation. "With a digital camera you're not just interested in a steady state but in what happens when the flash discharges, or memory is accessed. This system digitizes the current so operators can see current versus time and understand total current drain on the battery," says Bob Zollo, N6700 product manager.

The product is also designed to be significantly faster than other programmable power supplies. "In applications like automotive testing of antilock braking systems, test times are only 5-6 sec, so cutting a few hundred milliseconds from each test cuts overall time by 10 percent," Zollo says. Engineers generate a 0V to full-scale voltage change that is controllable from 100 µsec to 10 seconds with a single programming command, he adds.

Engineers can mix and match up to 16 different dc power modules to create a one- to four-channel system in a 1U-high package optimized for their specific requirements, selecting speed versus accuracy, for example. Integrating multiple outputs into a compact 1U design reduces overall system size over competitive units that only have one output.
http://rbi.ims.ca/4388-653

Sensors & Vision

See Things for Less Simplified setup contains cost and speeds installation

The PresencePLUS P4 GEO from Banner Engineering combines simple setup with low cost, bringing machine vision to more applications than ever. Yet the system doesn't sacrifice performance; it can detect an image even if it's rotated out of position.

The system drops the entry cost of vision to $995, bringing the technology to a range of applications not addressed by more expensive automated vision systems. Ease of installation lets less skilled workers set up the equipment. The system can be trained without programming by simply taking an image of a known good component.

It can then recognize items in a variety of settings. "The algorithm supports 360-degree rotation, so it doesn't have to be in the exact position of the known good product, and it will work even if it can't see all of the image" says Dan Holste, Banner's Director of Vision Products.

The system also adapts quickly to changes in production runs. "You can store up to 150 different inspection packages, so it's easy for a contract manufacturer to switch labels from company to company, for example," Holste says. Data can be sent over the unit's Ethernet connection, facilitating integration with other equipment. The camera also has a discrete output that can be connected to a relay that controls an arm that removes products that fail vision tests.
http://rbi.ims.ca/4388-654

Motion Control
Amplifiers & Drives

This Tiny Drive Pumps Up the Power Powerful embeded drive

The ZDR150EE 12A8LDC digital drive from Advanced Motion Control may be small, but it sure packs a wallop. Measuring just 2 × 2.5 × 0.73 inches, this PCB-embedded drive delivers nearly 1 kW of power for a peak power density greater than 250 W/inches³—or about 50 to 66 percent more than otherwise comparable plug-in drives. What's more, the ZDR weighs in at just 3.4 oz, an important consideration whenever drives are incorporated into moving components.

When embedded on a main control board—a task made easier by its arrangement of header row pins—the ZDR promises to eliminate some wiring headaches. According to Brad Dolbin, the company's manager of digital drive design, some control solutions would only need a wire to bring in power and another for the motor. Despite its small size, the ZDR didn't scrimp on features. It can operate in torque, velocity, or position mode to drive brushed, brushless, rotary, or linear motors as well as voice coils. And its digital functionality includes sinusoidal commutation.

Unlike some other competitive products, Advanced Motion Control managed to implement this drive on a single PC board. To squeeze everything into such a small package, Dolbin and his design team came up with an entirely new hardware and firmware architecture for this drive. They even asked their semiconductor vendor to modify the packages for their products. "We threw out everything we had been doing until this point," he says. "And we came up with something really revolutionary." The ZDR provides up to 6A continuous and 12A peak over a voltage range from 20 to 80V dc.
http://rbi.ims.ca/4388-655

Controllers

Double Standard Support Ethernet controller has more fieldbus support and computer-like memory

With the 750-841 Series programmable Ethernet controller from Wago, maybe more really is less. At $495, a fraction of what some PLCs cost, the 750-841 supports more fieldbus standards than comparable controllers; it can simultaneously communicate with both ModbusTCP and EthernetIP devices in either master or slave mode. "We're staying completely fieldbus neutral, which gives us the flexibility to talk to both kinds of devices," says Mark DeCramer, Wago's advanced electronics manager.

The 750-841 also differs from conventional PLCs when it comes to memory. Rather than the memory blocks found on a PLC, the Wago controller has a file system memory. "It operates as a PLC but has some functionality more like a PC," DeCramer says.

This memory feature makes the 750-841 suitable for more than control. "It's great for data acquisition, too," says DeCramer. For example, the file system allows users to write time-stamp data direct to nonvolatile memory and later access that data via an FTP client or as an e-mail attachment.

The 750-841 Series interfaces to Microsoft .NET-, UNIX-, and LINUX-based enterprise information architectures via HTTP, XML, DHCP, DNS, FTP, SNMP, and SMTP. An IEC 61131-3-compliant programming tool is available for $600 per site license.
http://rbi.ims.ca/4388-656

Feedback Devices

Cable Guide This device keeps draw-wire transducers on track

Tracking a single axis of motion in 3D space can be easy with the help of a draw-wire transducer. But many of these simple transducers have range-of-motion restrictions that limit their usefulness. That's where the patent-pending RoundAbout cable guide from Space Age Control Inc. enters the picture. When mounted on a cable-actuated position sensor, the device tracks one axis of motion in 3D space while minimizing the cable wear that can threaten accuracy over time. Two pulleys, mounted adjacent to one another inside the Roundabout's anodized aluminum housing, provide two dimensions of tracking; one of the two pulleys handles the displacement wire at any given time depending on its position relative to the center line of the housing. The third dimension of tracking comes from a cable-actuated rotation mechanism built into the housing.

While the Roundabout does have a second pulley that some less sophisticated cable guides lack, the unique feature of the device is its cable interface surface, which has a triangular profile. Whenever the cable starts to stray from the correct orientation relative to the pulleys, it comes in contact with that surface in such a way that the housing rotates to restore the correct orientation. "We evaluated many different geometries for the cable interface surface, and this one turned out to provide the smoothest dynamic motion, without any sticking points," says Tom Anderson, Space Age's applications engineering manager. Though Space Age created the Roundabout for cable-actuated position transducers, it can also be used for a broad range of cable control applications. Anderson says SpaceAge engineers have even come up with a way to make a rudimentary coordinate measuring machine using several of these devices together.
http://rbi.ims.ca/4388-657

Mechanical Components

Bronze Free Bearing Lubricated plastic takes on traditional bearing materials

iGlide R engineering plastic bearings from igus inc. do away with the maintenance hassles and uneven performance that can plague traditional bronze bearings over time. The company injection- molds these bearings from a proprietary compound based on a UV-resistant, reinforced nylon with an internal dry lubricant.

And because the lubricant is distributed evenly throughout the thickness of the molded part, these bearings offer a dynamic COF that remains stable (at 0.080) throughout the entire service life. Unlike most bronze bearings, iGlide R doesn't require any extra lubrication at all. When first used, the iGlide R bearings transfer a low-friction coating onto the shaft. "Then they just run without any other maintenance," says Tom Miller, igus' bearings manager. The plastic compound used in iGlide R is proprietary, but that isn't all that sets it apart from both bronze bearings and those made from other internally lubricated thermoplastics. According to Miller, the company's engineers have performed many years worth of tribological testing. All of this test data has been distilled into a "predictability calculator" that tells design engineers what they need to know about a bearing's wear rate and life expectancy. "Whether the bearing has been in use for one day or five years, you know exactly how it will perform," he says.

Available in flange, sleeve, and washer styles in a variety of sizes, iGlide R bearings target a wide range of applications. Miller notes, for example, that its UV-resistance makes it ideal for outdoor use and agricultural equipment. http://rbi.ims.ca/4388-658

Motors

Mount It, Run It No gearbox or multiple-bearing setup for this direct-drive motor

Danaher Motion's Cartridge DDR motors aim to combine the best features of direct-drive torque motors with those of conventional servo motors. Using a patented electromagnetic design to produce higher torques, DDRs eliminate the need for external gearboxes, while simultaneously doing away with the multiple-bearing configurations of direct-drive motors.

"If you have a conventional direct-drive torque motor, you'll always have the 'align-the-bearings' problem, and if you have a conventional servo motor, then you're going to need a gearbox to produce high torque," notes Chris Radley, senior product line manager for Danaher Motion. "But here we have a very high-torque direct-drive motor, and it uses no bearings at all." By doing so, the DDR offers less maintenance, reduced downtime, zero backlash, and improved reliability, as well as better positioning and velocity regulation, according to Radley.

Danaher engineers estimate that the patented design can reduce operating costs by $10,000 on a single motion axis over five years, as well as eliminate setup headaches.

"Using direct drive, we've made it possible to have a motor up and running in a machine axis in under an hour," Radley says. "For the customer, it's a 'mount-and-run' motor."
http://rbi.ims.ca/4388-659

Hardware & Software
CAD Software

3D Focus Expanded tools to make widest impact in machine, mold, and consumer products design

Staying focused—and staying focused on 3D—is what has helped differentiate SolidWorks 2005 from its competition as more users are moving to 3D, asserts Fielder Hiss, the company's Manager of Product Management. Two significant additions to the CAD software, he says, are the COSMOSXpress^™ , which is a built-in analysis tool within a 3D mechanical design system, and the MoldflowXpress, which is a wizard-based design validation tool that can automate the creation of cores and cavities with built-in mold design tools and test the manufacturability of plastic injection-molded parts.

"We've looked at industries that are mainly machine design, mold design, and consumer products design, and functionalities that would impact those customers so that we can stay very focused to help them be successful," Hiss adds.

In addition, reuse of design information is another area that SolidWorks 2005 has addressed, Hiss comments. Also featured in the software is a design library that stores commonly used parts, assemblies, and 2D annotations and blocks, which users can easily drop into their designs.

Declining to pinpoint future updates, however, Hiss says SolidWorks will continue to focus on ease of use. Examples of such a focus are the eDrawings™ tool in SolidWorks 2005, which is e-mail-compatible, and the ContentCentral™, which is Web-acceessible.
http://rbi.ims.ca/4388-660

Analysis Software

Analyst's Wish List Cosmos developers listen to users

COSMOSWorks 2005 is a major update from the previous version to incorporate the most popular requests from COSMOS users—currently at more than 12,000 companies in a wide array of industries—says Suchit Jain, VP of Analysis Products. Most significant among all the new features is the "drop test" that allows users to easily analyze high-impact stress reactions, a rarity in software that costs less than $7,000, Jain comments. The updated software also comes with specific capabilities, such as "pin," "bolt," and "press fit," to simulate all types of real-life part interactions within an assembly, simplifying the process to solve such interactions, Jain adds.

Other updated features include fatigue and nonlinear analysis. In terms of motion and flow simulation, COSMOSWorks can automatically derive loads from a motion simulation, making it even easier for users to define analysis inputs. Users can also automatically transfer wall pressures from a flow simulation to do structural analysis. The user interface is another area that has been improved. The software comes with intuitive visualization tools, including those to import data from physical test and the factor of safety wizard. Collaboration tools include HTML report, eDrawings for analysis results, AVI's, etc. Fully integrated with SolidWorks^® 3D modeling software, COSMOSWorks 2005 continues to allow engineers to test a design and run multiple iterations without ever leaving SolidWorks.
http://rbi.ims.ca/4388-661

Test & Measurement

Testers' Choice Though loaded with options, this tester price drops about 40 percent

Simplified setup for a number of different functions is a key benefit of the 34980A multifunction switch/measure unit from Agilent Technologies. Its 19 plug-in modules offer a broad range of functionality with low frequency, RF, and microwave switching to 20 GHz, digital I/O and digital-to-analog converters, and counter/totalizer capabilities. The unit can house up to 560 two-wire multiplexer channels or 1,024 two-wire matrix crosspoints in one mainframe.

And all this versatility comes at a low cost. "Compared to VXI or PXI products, we're up to 40 percent less for a typical system," says Sheri Detomasi, 34980A product manager.

Connection to PCs and other gear can be made with USB, LAN, or GPIB links. Engineers can use the Ethernet connection and the unit's graphical Web interface to remotely access and control the instrument, monitoring test setups or troubleshooting an application via a standard Web browser. Setup is further simplified by reduced wiring. "This has an integrated digital multimeter, so signals can be routed directly to the DMM, eliminating a lot of complex wiring," Detomasi says.

When one set of tests is finished, it's easy to set up for another trial. "The 34980A has eight slots, engineers can pick from 19 modules, do their project, then swap modules out for the next project," Detomasi says.
http://rbi.ims.ca/4388-662

Hardware

Mach-Speed Computing Fast computer cruises through benchmark tests

All supercomputers are fast. That's why they're called supercomputers, right? Well, how's this for fast: In benchmark tests running an LS-Dyna crash analysis on a Dodge Neon, the Cray XD1 supercomputer solved the analysis in 429 sec! You'll find the results at www.topcrunch.com, a DARPA-funded site that tracks the performance of high-performance computing systems. Now, the Cray results were actually the second fastest in the test, 7 sec behind an Itanium system. But who's counting? Cray engineer Adam Lorant says Itanium systems are more expensive than the Cray XD1, and he has a point.

If you're thinking that the Neon is an old car and that its design may not be all that challenging for a high-performance computer, you're right. Actually, the XD1 didn't even break a sweat in finishing the analysis in 429 sec. But customers running LS-Dyna tests of more complex modern designs on the XD1 are seeing similarly fast processing times. Indeed, in other tests reported by Topcrunch, the XD1 was 90-percent faster than a Xeon/Myrinet cluster and 90-percent faster than an Opteron/Inifiniband cluster.

Enabling the Mach-like speed is a high-performance interconnect linking all the processors in the system. Additionally, FPGAs (field-programmable gate arrays) act as co-processors that accelerate specific algorithms.

It's performance-enhancing features like that which prompted Design News readers to select the XD1 as the best computer-hardware product of the year—and not just because engineers generally like things that go fast. The kind of high-performance computing the Cray XD1 provides makes it easier and faster to do the rigorous finite-element and fluid-dynamics analysis often required for many complex products being designed today.
http://rbi.ims.ca/4388-663

Fluid Power
Connectors and Components

Tube Nut Alternative Hydraulic connector simplifies automotive braking assemblies

Engineers at ITT Industries Fluid Handling Systems division predict that one day, all of the 17 million vehicles built annually in the United States could incorporate their quick-connect device, not only for braking systems but also for a host of other hydraulic applications.

Known as HPS Quick Connect, the device eliminates the tube nut that traditionally attaches hydraulic tubing to the bore of a brake assembly and replaces it with a press fitting. The new design enables braking system suppliers to thread the Quick Connect together at their own facility and then send it to the OEM facility, where it can simply be snapped together during final assembly. "Today, everything is threaded together by the OEM, which causes difficulties, especially with access of wrenches and torqueing equipment," notes Dave Malone, product development supervisor for ITT Industries Fluid Handling Systems. For OEMs, the new hydraulic quick-connect potentially enables downsizing of braking modules, as well as reduction of scrap, rework, and possible warranty claims, all without requiring a change in the connection bores used on today's systems.

ITT engineers say that the connector could be placed on numerous bores throughout a vehicle, ranging from as few as one to as many as 20. "We're already looking at applications where they want six of them on a vehicle," Malone says. "Eventually, there's potential for all the nuts in the hydraulic assemblies to be replaced with the Quick Connect system."
http://rbi.ims.ca/4388-664

Hydraulic Systems and Controls

Valve Keeps Things Cool Simple design improves pressure drop, temperature control

A two-way proportioning valve driven by a stepper motor, the Electronic Control Valve by Engineered Machined Products is designed to replace conventional wax-based thermostats used in automotive temperature control. Key to the valve is a simple design that uses a threaded shaft to move a piston shuttle back and forth, which regulates the coolant flow with low restriction, says David Allen, Executive VP of Product Development.

According to the company, the low pressure drop across the valve increases system flow, reducing coolant system parasitic losses. Intended for automotive and diesel applications, this valve has demonstrated a reduction in oil friction by controlling coolant temperature to within 2-3C to maintain oil temperature for gas engines.

Thanks to a low leak rate, the valve can significantly decrease engine warm-up time during cold starts while also solving the issue of overcooling in winter and undercooling in summer, keeping the internal engine components at the optimal operating temperature. For automotive OEMs, this means more efficient emission control and fuel economy. Among the current customers is a U.S.-based OEM that intends to use the valve for heavy diesel applications, Allen says.
http://rbi.ims.ca/4388-665

Pneumatic Systems & Controls

Cushion Softens the Blow Viscoelastic cushion adjusts to load variations

Ace Controls Inc.'s viscoelastic NuCushion softens the "bang-bang" blows of pneumatic actuation without adjustment, no matter the velocity or force of the blow. The viscoelastic cushion, designed to fit on air cylinder pistons, represents a departure from the air-based devices that have long been used to soften the impact of fast-moving pneumatic actuation.

Unlike air cushions, the new device doesn't need to be tweaked whenever an end user changes the size or speed of a load. Ace Controls' engineers say that the viscoelastic material's rate dependency under load allows them to naturally adjust to variations. "Whereas air will react in the same manner under all conditions, a viscoelastic material will react one way if you hit it fast, and another way if you hit it slowly," notes Mike Ferkany, engineering manager for Ace Controls. "It's ideal for someone who has variability that they can't control in their operation."

NuCushion, which employs a proprietary variation on DuPont's well-known Hytrel thermoplastic elastomer, lends some simplicity to automation projects: It not only does away with the need for air adjustments but also eliminates the need for bleed needle assemblies and cushion spuds, as well as the seals that are part and parcel of air cushioning systems. Moreover, the viscoelastic cushions also cut the clicking noise that normally occurs when pistons hit home during fast cycling. "If you have an application where the end users object to noise, or have a lot of variability in their operation, this is a good solution," Ferkany says.
http://rbi.ims.ca/4388-666

Materials & Fastening
Materials Enabling Technologies

Swanky Enclosures for the Masses Plastic overmolding incorporates real wood and decorative metals

Consumer electronics that look expensively handcrafted can really stand out from the crowd. Inclosia Solutions, a business unit of Dow Plastics, has developed a way to impart that high-end look to mass-produced products. The company's EXO overmolding technology, which started out as a way to add decorative fabric skins to plastic parts, now allows a wide variety of wood veneers and decorative metal foils to be incorporated into injection-molded thermoplastic enclosures. "We can use just about any kind of wood or metal as long as they're available in a veneer or foil thicknesses," reports Tom Tarnowski, an engineer and Inclosia manager.

Whatever the decorative material, the EXO process consists of three key steps: It starts with the robotic or manual placement of a precut fabric, wood, or metal insert inside the mold cavity. The first shot of plastic, typically a rigid thermoplastic like PC/ABS, is then injected onto the back of the decorative material. The second shot of plastics, usually an elastomer, encapsulates the edges of the first two materials, creating the finished part. Inclosia's proprietary take on overmolding technology overcomes several technical challenges—including CTE mismatch and adhesion between materials as well as tooling and processing complexity. "Our expertise involves knowing how to tailor the overmolding process to the various material combinations and part geometries," Tarnowski says.

And despite the upscale look of the finished parts, the process is truly intended for mass production. Given the cost of injection molds, Exo wood and metal overmolding generally doesn't start to make sense until you reach production volumes that start around 10,000 and climb into the millions.
http://rbi.ims.ca/4388-667

Joining Technologies

Surface Mount Fasteners These panel fasteners install directly on PCBsduring soldering operations

Loose fastening hardware doesn't have to get in the way of automated electronics assembly operations. PennEngineering's ReelFast SMT system uses surface mount technology to install panel fasteners directly onto printed circuit boards. These fasteners install on solder pads, using the same automated soldering equipment as the board's electronic components. The fastener, in essence, becomes just another board component.

As their name suggests, ReelFast panel fasteners come in tape-and-reel packages suitable for use with existing pick-and-place robots. Jay McKenna, PennEngineering's special projects manager, reports that ReelFast fasteners install in about 0.3 sec, versus as much as 30 sec for a broaching fastener. "Not only is the new system inherently faster to install, but it also eliminates handling operations," he says.

The new system also lessens the risk of damaging a fully populated board when installing a broaching fastener. As McKenna explains, broaching processes subject the boards to significant amounts of stress, which can ruin the board when they're at their most expensive. For example, install forces for a typical broaching fastener would be between 200 and 300 lbs. ReelFast install forces, by contrast, reach just a few pounds, according to McKenna. Once installed on the board, the ReelFast hardware exhibits as much strength as an equivalent broaching fastener. In both cases, "the circuit board will delaminate before the fastener fails," McKenna says.
http://rbi.ims.ca/4388-668