Engineering News 8093

Winter sports heat up with plastics

Polymers overcome weather/cost/weight barriers in the design of winter sports equipment

Gary Chamberlain, Senior Editor

Newton, MA--Cold weather proves tough on materials, particularly sports equipment that must perform under high-impact, low-temperature conditions. In one winter sport after another, however, plastics live up to the challenge. Here's a look at how some fine-tuned polymers improved the designs of snowboards, snowshoes, and snowmobiles.

Snowboarding has become one of today's fastest growing winter sports. And today's athletes demand equipment that enhances performance and increases the user's comfort level. The latest iteration: a snowboard shock absorber system first popularized in such outdoor sports as roller skating and mountain biking.

Incline Inc. (Portland, OR) had such a system on the drawing board. Like anything with a suspension, a snowboard with shocks provides more control at greater speeds. Added comfort comes from the system's ability to dampen the jolt-inducing vibrations.

Incline's system consists of two foot plates that fit between the binding and the snowboard. "It allows for vertical movement of the binding in relation to the board," explains Kaj Gyr, head of R&D at Incline. "This helps the athlete retain an edge control."

When Incline engineers looked for a lightweight material to build the Snoshox system around, they found what they needed in a long-glass-fiber-reinforced, structural polypropylene composite. The material selected: Verton(R) MFX from LNP Engineering Plastics (Exton, PA).

What Gyr likes about the Verton composite for this application is its low specific gravity and high tensile strength. "The material maintains impact performance through sub-zero temperatures, which is really important to us," Gyr adds.

"Weight was the main concern when we were engineering the system," Gyr adds. "Because Verton is so lightweight, our shock absorption system adds just 2.0 lb to the snowboard. Snowboarders easily trade a slight increase in weight for the performance advantages."

Added-traction snowshoes. Winter sports enthusiasts continue to discover a long-time favorite--snowshoeing. But this new breed of snowshoe lovers also demands a product that's attractively priced.

Tubbs Snowshoe Co.'s (Stowe, VT) approach incorporates an elastomeric polyurethane that encapsulates the aluminum frame in the design of its latest models of snowshoes. In making the choice, Tubbs looked beyond the thermoplastics used in its current line of shoes. The material that beat out thermoplastics: Bayflex(R) 110-25 reaction injection molding (RIM) system from Bayer Polymers Div. (Pittsburgh).

The Bayflex elastomer polyurethane RIM system produces a solid urethane elastomer. Benefits include: large-part moldability, toughness, good surface quality, fast cycle times, and, as in the snowshoe application, encapsulation.

"This is the first time we have used a polyurethane RIM system," says Fran Mahoney, R&D engineer for Tubbs. "Our primary challenge was to maximize performance and minimize weight under very low temperature conditions." Other properties Tubbs sought: tear, puncture, and abrasion resistance; flexibility; and design freedom. The Bayflex system answered all of these needs, Mahoney adds.

Use of RIM not only enables Tubbs' new Trekker Series of shoes to remain flexible at low temperatures, but they also last longer. Moreover, the material adds molded-in traction to the shoes, while resulting in a less labor-intensive manufacturing process. For example, it takes 15 to 20 rivets to attach a thermoplastic to the aluminum frame, Mahoney points out. The RIM encapsulation process requires no rivets to join the polyurethane to the frame.

High up-front costs of thermoplastic tooling also played a role in the decision to go to the RIM system. The molder, Milfoam Corp. (Hamden, CT), inserts a tubular aluminum frame into a machined aluminum mold. The composite design enhances the snowshoe's torsional rigidity.

The elastomeric polyurethane is shot into the mold, where it encapsulates all but a few exposed inches of the frame to form the shoe's decking. Wall thickness of the polyurethane ranges from 0.750 inch to as little as 0.115 inch. The toe axle, a drawn aluminum alloy, is molded into the polyurethane, as are the tire-like treads on the bottom of the shoe.

After the molded shoes arrive from Milfoam, Tubbs only has to add the binding assembly with four rivets and brand the shoe via hot stamping. Despite their toughness, the shoes weigh just over 5 lb per pair.

Better snowmobile bumpers. Arctic Cat Inc. (Thief River Falls, MN) needed help in redesigning the front and rear bumpers for its 1999 line of snowmobiles. What it wanted was a material that would give the bumpers added strength and a better surface appearance. It found that material in a toughened nylon 6. In the bargain, Arctic Cat got some valuable design assistance from the material's supplier, DSM Engineering Plastics (Evansville, IN).

DSM needed to provide Arctic Cat with a material that didn't sacrifice strength and impact resistance at temperatures as low as -40F. It suggested that the snowmobile maker switch to Akulon(R) J-7/33/UV, a 33% glass-fiber-reinforced nylon 6 with a UV stabilizer package. DSM also pointed out that the material would result in cost and weight savings over the Arctic Cat's other candidate, a long-glass polypropylene.

"Our new bumpers embody everything we wanted to achieve when designing plastic and composite components, especially when it comes to ergonomics and aesthetics," reports David Branscomb, the company's plastic components engineer.

Proprietary impact modification technology developed at DSM gives Akulon added impact strength across a wide temperature range, without sacrificing a good balance of stiffness. And, because of its nylon 6 base, the compound demonstrates good flow properties; thermal performance; weld-line strength; surface appearance; and scratch, mar, chemical, and age resistance.

There's another twist to this scenario, however. Arctic Cat wanted to use gas-assist technology for the bumpers to take advantage of the added strength and design flexibility it offers. For this, they turned to Mid-Central Plastics (West Des Moines, IA), a molder with presses large enough to run the parts using a gas-assist.

"Akulon established a nominal wall thickness better than that of a long-fiber polypropylene," says Gary Keeney, Mid-Central's production engineering manager. Best of all, by incorporating gas-assist and an impact-modified nylon 6 into the design, Arctic Cat ended up with a hollow-core bumper that offered a 23% cost savings and 30% reduction in assembly time over a polyethylene-covered, steel-tube bumper."

What this means to you

Benefits of CMPT process:

Move over metals, enter fiber-reinforced plastics

Linden, NJ--Design engineers have long recognized the performance capabilities of fiber-reinforced plastics. But, the high cost and long turnaround times associated with the tooling often discourage their use.

Not anymore, if General Magnaplate has its way. According to Edmund V. Aversenti, the company's vice president and corporate director of operations, its CMPT^TM process could help bring about a movement to replace metal parts with fiber-reinforced plastics. The process reduces the total time needed to make large layup-molds (toolfaces) for complex reinforced composites from six to 12 months to as little as six weeks, while slashing costs by one-third.

CMPT is a dense, multi-directional, metal-weaving process that eliminates the need to make tooling out of large, heavy-metal ingots or castings. The process eliminates the need for CNC time. A prototype, clay, plaster, or metal part is sent to General Magnaplate to make the tool. If no part is available, the company creates a plastic model from which it then creates the tool.

With this new process, high-temperature tooling for long or short production runs is possible for cures up to 750F, and compaction pressures are possible to 1,500 psi. The toolface can be made from any alloy, from aluminum to zinc, including high-nickel INVAR.

The metal toolface can be used to produce high-temperature composites (such as Bismaleimide resins), whose heat resistance can stand up to such applications as automobile hoods, hot/wet applications on jet engines, and primary structures of the high-speed civil transport (HSCT). "This new process represents a quantum leap in the composite fabrication industry, making it possible to drastically lower the final cost for many molded, complex-shaped parts, especially those with contours," says Aversenti.

Polyboxes modernize medical instrument cleaning

Douai, France--Marking a "new era" in sterilization containers for medical instruments, the French company Polybox Medical has developed the Polybox. The polycarbonate container replaces stainless steel or aluminum counterparts, long a staple for this use.

The container measures 733.1631.18 inches, wide enough to hold splayed forceps, and can be used for cold decontamination or autoclave steam-heat sterilization. In the case of steam sterilization under autoclaving conditions, a material must withstand temperatures to 250F (121C) for 15 to 30 minutes--and it must do so for many sterilization cycles. Polybox Medical claims its boxes can do just that. Unlike metal sterilization containers, the Polybox is transparent, enabling the instruments to be easily identified without opening the container, helping to ensure uninterrupted sterilization. Easily stacked, a special interlocking feature makes it easy to handle several containers at one time.

Due to the durable polycarbonate used in their construction, the boxes will retain their shape forever, the company reports. They come in yellow, orange, green, and blue colors that are guaranteed not to fade.

SPE awards honor part art

Detroit,--"If you work with your hands and head you are a craftsman," echoes Bonnie Bennyhoff, chairperson of the Society of Plastics Engineer's (SPE) Automotive Div. "If you work with your hands, head, and heart you are an artist." These words of Louise Nyser summed up the theme of the 1998 SPE Automotive Div.'s award program, "The Art of a Part."

This year's Grand Prize, also winner of the Body Exterior Award, went to Mitsubishi Motors for its composite bumper I-beam used on the 1999 Galant.

In its design, engineers replaced RF steel with Azdel(R) C-467 from Azdel, (a joint venture between GE Plastics and PPG). Continental Structural Plastics compression-molded the I-beam. The result--a 35 to 45% lighter part that offers cost savings up to 25%.

The I-beam also uses a glass mat polypropylene material and integrates mounting tabs for fascia and attachments stays that slide into the car's frame rails--decreasing tooling and assembly costs by 20%. The bumper beam can absorb enough energy to meet the 5 mph federal safety and pole-impact standard.

The art doesn't stop there. Seven other category award winners were also honored at the ceremony. These winners are:

The second winner in this category is General Motors' GMT800 clutch pedal and bracket assembly for the C/K pickup truck.

The assembly replaces stamped steel parts and offers snap-push rod-to-pin assembly of the pedal and bracket. The assembly is manufactured by Florida Production Engineering from BASF's Ultramid(R) nylon 6 resin. The molded-in color nylon pedal assembly offers lower pedal movement and a weight savings of 65%.

"Normally, engineering is not considered an art form," says Bennyhoff. "But in using plastics, engineers today are developing almost an artistic sense to envision creative ways they can improve vehicle component design."

Tomahawk gets a low-cost makeover

by Laurie Toupin, Associate Editor

Tucson, AZ--The U.S. Navy Tomahawk cruise missile, recently fired into Iraq during the Desert Fox campaign, is getting a face lift. In 2003, the Navy will debut the Tactical Tomahawk (T²), designed by Raytheon Systems Co. Military personnel will be able to reprogram the newest cruise missile in mid-flight, command it to loiter or overfly the target areas while assessing battle damage, and, if necessary, redirect the missile to some alternate destination.

Engineers not only made it better, but made it less expensive, says Bruce Ganoe, vice president of the Precision Strike Product Line for Raytheon. The next generation of long-range Tomahawk cruise missiles will cost less than $570,000 each, half the estimated cost of $1.1 to 1.4 million for the previously planned missile upgrade.

To reduce expenses, Navy and Raytheon engineers analyzed the price of each component as well as every engineering requirement and its associated cost. Ganoe says, "We asked, 'Which requirement could be changed to reduce production expenses?'" In the case of the Tomahawk, the driving factor was the missile-launch location.

Presently, missiles are fired from the torpedo tubes on ships and submarines, Ganoe says. The Tomahawk breaks the water surface carrying a 1,000-lb warhead and hugs the terrain at 550 mph. It has an 85% direct-hit record and a range of approximately 1,000 miles.

"Firing from the torpedo tube requires a tremendous amount of structural elements within the missile airframe that increase the weight dramatically," he says. "Because the missiles are stored inside the hull of the torpedo tube, they must meet extremely stringent shock requirements--those imposed by a near-miss nuclear depth charge." In order to reduce the weight and, subsequently, the cost of the airframe, the Navy opted to eliminate the torpedo launch option. Instead, the T² will be fired from vertical tubes only where the structural requirements are less rigid.

With a lighter casing, there is more fuel capacity. But instead of increasing the missile's range, engineers installed a less- expensive engine with as much thrust but one that requires more fuel. "We can attain essentially the same range at a much lower cost," Ganoe states.

Military planners can now store a number of missions in the missile and choose one after launch. "There is always a primary mission," he says, "but you can change your mind and send the Tomahawk on Mission 3 instead of Mission 1." Using a satellite-based communication system, or a communique from a manned aircraft, commanders can give the missile new coordinates.

Raytheon engineers also improved the recertification time. "We increased the time that these missiles can stay out in the fleet," Ganoe says. Missiles usually come back every five or six years for recertification. Tactical has a 15-year service life. "This is a tremendous help to the Navy," he adds. "It's almost worth a new ship to them over a few years."

How did they make them so reliable? "We got a lot of our design ideas from the automotive industry." For example, engineers examined how Cadillac could sell such a reliable car for $55,000 complete with a GPS system on board, a 2-way data-link, and airbags with initiators that are similar to those used on a missile.

T² engineers also moved the majority of the avionics to a common location, which requires less cabling and connections.

The Tactical Tomahawk will sport a more jam-resistant Global Positioning System tracking system.

Inserts take the tang out of fastening

by Christine M. Ferrara, New Products Editor

Hampton, VA--Some fasteners are supposed to conduct electricity, but when a broken tang from a tanged helical-coil insert does, it can be dangerous. That's why Pressure Systems Inc. started using inserts without tangs from Kato Fastening Systems Inc. (Newport News, VA) for their pressure measurement instruments.

John Shirley, chief of Pressure Systems' model fabrication shop, saw an advertisement for helical inserts without tangs in a trade magazine that showed an electrical arc between a screw and a circuit board.

The ad depicted how inserts without tangs, which were at that time in preproduction between Kato and Fairchild Aerospace Fastener Div., could eliminate this problem and the additional problem of removing the loose tang after inserting the coil. A tang is a part of the insert's configuration used to drive the metal insert into a hole. The tang must be broken off once the insert is installed.

Instead of tangs, inserts without tangs have a notch on the inside of the first coil on both ends of the insert, thus making the insert bidirectional, according to Rich Davis, president of Kato.

Tangs work like the slot on the end of a screw, giving the operator something to grab. The tanged inserts present special problems in certain applications. "You have this broken piece of metal floating around in what are usually very expensive electronic housings used in aircraft, missiles, and communications equipment," Davis adds.

Getting the tang out, Davis says, can be "a chore" if the insert is a small thread size or if the hole is a small or blind one. "You have to jump through a lot of hoops to get this small piece that is less than 0.086 inch out of the bottom of a hole in small thread sizes."

Since there are no tangs to break off or lose, the manufacturer does not have to have a secondary operation of accounting for the broken tangs. "Some of our big customers will give assembly people 1,000 tanged inserts and say, 'Once you're done, we have to have 1,000 tangs back so we know we haven't contaminated the parts,'" Davis says.

Helical-coil inserts, whether they be tanged or without tangs, provide strong threads in lightweight metals such as aluminum and magnesium used typically in aerospace applications in housings that have electrical components. Other applications for the inserts without tangs include electronic, commercial, automotive, and office equipment. Inserts without tangs are for high-volume, small thread-size users that specify threads from 2-56 through 1/4 inch, Davis says.

The inserts also provide locking threads to prevent the screw from vibrating loose from the part, critical in aerospace applications. "You put a locking insert into the part, and then you put the screw in, and the screw will not vibrate out and fall into some critical assembly and contaminate it," Davis adds.

Inserts without tangs also feature a foreign object damage (FOD)-free design. "The whole focus in the aerospace industry is FOD-free designs," Davis notes.

Davis adds that inserts without tangs are bidirectional. "The insert does not have to be oriented in one particular direction to install it, while the tanged inserts have to be."

Kato demonstrated the inserts without tangs to Pressure Systems, who use them on their pressure measurement instruments. The equipment operates in areas which cannot be contaminated, Shirly says.

Since that time, Kato has improved the tooling used to install the inserts without tangs. Users, primarily aerospace and defense contractors, use electric and pneumatic tools to install the inserts. Pressure Systems has recently begun using higher-speed electrical tools to install the fasteners, Davis says.

CAN comes to microcontrollers

Austin, TX--Both Motorola and Microchip Technologies (Chandler, AZ) are introducing devices with CAN (Controller Area Network) interfaces to help the automotive market simplify networking and reduce wiring.

CAN is a serial protocol that supports distributed real-time control with a high level of data integrity. Applications include industrial and embedded control. CAN is already the bus of choice for European automotive applications, and U.S. automakers are beginning to adopt it as well.

Motorola has launched what it claims is the first dual CAN microcontroller for automotive gateway applications and has plans for a four CAN device.

Gateway modules, which manage communication flow over CAN buses, are becoming critical to automobiles as demand for in-car electronics increases. Motorola estimates that the gateway market will grow from 4 million units in 1999 to 14 million in 2003.

Based on Motorola's M68HC12 16-bit architecture, the new M68HC912DG128 includes 128 kbits of flash memory so designers can develop systems tailored to their own applications or make needed field modifications. The flash memory also lets a single controller handle more than one type of application.

The microcontroller will let engineers do such things as integrate all of their network diagnostics into a single controller in a single module, or node. Placing the device in a module such as the instrument cluster would reduce wiring because this node requires information from two networks.

Meanwhile, Microchip Technologies announced its support for CAN through products including interface controllers and a new PICmicro family of 8-bit RISC microcontrollers.

The first planned device is an 18-pin stand-alone CAN controller that features an SPI serial interface for communicating with a PICmicro device. The controller will enable CAN support across 60-plus PICmicro devices, providing a migration path for CAN designs. The $3.00 to $5.25 devices will be available in the first quarter.

Microchip will follow with a new PICmicro family of initially four chips featuring on-chip CAN functions and a variety of peripherals. Based on the PIC18Cxxx 8-bit microcontroller architecture, the devices will be available in flash, one-time-programmable (OTP), and ROM versions. Volume production will begin in the second half of 1999; pricing will be $6 to $10.

Software smoothes simulation

Sweden--Before any design goes to "print" it is displayed in front of numerous scrutinizing eyes. Events such as board meetings, design department internal reviews, and informal meetings are all stepping stones that lead up to a finished product. Recognizing that presentation is critical in these instances, BMW teamed up with Prosolvia to co-develop a software application for automotive styling and design--Oxygen SketchMap.

With Oxygen SketchMap, "users have the ability to go from 2D paper sketches to full-scale VR models in just a couple of hours," says Martin Wengblad, president of Prosolvia. "Time-to-market is crucial in the automotive industry and Oxygen SketchMap will allow companies to quickly move from hand-drawn sketches to virtual prototypes."

The software is used to scan 2D drawings into the computer and apply them on objects to create full-scale 3D virtual reality models. Once complete, users view the model in Prosolvia Clarus' Oxygen Showroom^TM, a real-time interactive environment for presenting, reviewing, and evaluating product designs side-by-side with reflections and shadows. The software is designed to support conceptual design efforts as well as detailed design for face-lift projects.

At BMW, members of the styling department use Oxygen SketchMap to translate the data from a new car concept worked out in Alias/Wavefront CAD software (Alias/Wavefront; Toronto, Canada) to develop 3D sketches for presentations and display purposes. Yet, BMW still uses clay models for detail work--especially where quality targets are extremely high in design.

According to BMW, this software tool serves as a catalyst to augment and support the clay sculptors. "Computer representation is adequate," says BMW, "but when it comes down to the final judgement, clay has the highest resolution." BMW actually builds full-scale, clay models that often weigh more than the actual car.

While savings aren't visible in time, BMW says that visual quality has increased as has the number of design possibilities engineers are able to explore."This joint effort began in 1996," says Dr. Timm Kehler of BMW, "Prosolvia has been extremely customer-oriented, reacting very well to our needs, not only in a superficial sense, but in the software itself. We really feel like someone's listening to us."

However, Kehler comments that at BMW, "We don't use digital tools to reduce time and cost. We try to establish the most creative design process. The main imperative is quality rather than time, as time constraints tend to impair the creative process."

Integrating control and servodrive increases accuracy

Benicia, CA--When Metlsaw Systems needed to upgrade the control system on its high-speed sawing machines, company engineers turned to Rockwell Automation. "All of our equipment is designed to eliminate subsequent machining," says Ken Forman, president of Metlsaw. "Accuracy requirements led us to a system that tightly integrates motion control and drive functions."

Other concerns, according to Metlsaw electrical engineer Tom Kvech, include reduced space and improved functionality. Allen-Bradley's 1394 GMC servo controller provides a platform for integrating multi-axis motion, logic and I/O control, positioning and servo-drive functions in a single module. "This eliminates the need for complex integration of motion-control and servo-drive functions," Kvech explains, "saving significant panel space and reducing installation and programming time."

Metlsaw's machines can cut an entire 30-foot length of bar and have every part within a thousandth of an inch, says Kvech. "And programming the system is easy. So when we need to make custom changes or updates, we can do it quickly and efficiently."

The 1394 servo controller incorporates the Allen-Bradley GML Commander motion-control programming software. GML Commander provides Metlsaw with one language to learn.

For most of its machines, Metlsaw uses a 30-hp induction motor to power the saw blades. Two Allen-Bradley 1326A ac brushless servo motors are also used--one for the backgauge and one for the carriage drive. Operator interface is via an Allen-Bradley PanelView 900 monochrome flat-panel terminal, that is networked directly to the 1394 motion controller using Allen-Bradley Data Highway 485. The GML application program handles the PanelView messaging, as well as the Allen-Bradley Flex I/O modules. Other Rockwell Automation components include a SMC-2O smart motor controller, which provides the soft-start function for the saw blade, Bulletin 194 disconnect switch, and Bulletin 1492 circuit breakers.

"Customers rely on these machines for productivity. When one goes down, it's a serious problem because we have maintenance contracts with most of our customers," explains Forman. "Reliability has been phenomenal," says Kvech. "It has really made a huge difference for us; we maximize our profitability when we can minimize the amount of time we spend troubleshooting machines."

Group delivers benchmarks for embedded processors

San Jose, CA--After more than a year and a half of planning, discussing, voting, and developing, the EDN Embedded Microprocessor Benchmark Consortium (EEMBC--pronounced "embassy") demonstrated its first set of benchmarks for embedded control systems during November's Embedded Systems Conference. The benchmarks represent more than 40 real-world and synthetic C source code algorithms targeting the automotive, industrial, consumer, networking, office automation, and telecommunications markets.

EDN Magazine, a sister publication of Design News, founded EEMBC in 1997; the president is EDN Editor Markus Levy. Twenty-one semiconductor vendors and IP suppliers are charter members of the consortium. They include: Analog Devices, IBM, Lucent, Motorola, National Semiconductor, Siemens, Texas Instruments, and Toshiba.

The group's goal is that their benchmarks provide key metrics for helping embedded system designers select microprocessors, microcontrollers, or DSPs for their designs.

Jewel bearing splits anemometer start speeds

Newton, MA--A low-friction jewel bearing from Waltham, MA-based Bird Precision helped Nielsen-Kellerman Co. (Chester, PA) cut anemometer starting speeds in half when compared to existing designs. While most portable anemometers require wind speeds of between 0.6 and 0.8 m/sec to set the impeller in motion, the Kestrel series' impeller rotates in 0.3- to 0.4-m/sec winds, says Nielsen Kellerman's Michael Naughton.

Bird Precision designed the super-polished, sapphire, conical-vee bearing that supports the patented, anodized-aluminum impeller used in both the Kestrel(R) 1000 and 2000 anemometers. The ultra-low coefficient of friction allows the anemometers to register nearly imperceptible breezes (0.7 mph), explains Naughton, yet also measures gale-force winds (up to 89 mph), with an accuracy of plus or minus 3% or better.

Less than five inches long and weighing only 1.5 oz, the anemometers let anyone that works or plays outdoors measure even low windspeeds with high accuracy. A sturdy fiberglass housing protects the 25-mm impeller from damage. But if need be, the impeller is easily replaced without tools at a cost of about $15.

"Most portable anemometers weigh over one pound and are less accurate," says Naughton. The Kestrel 1000 pocket wind meter and the Kestrel 2000 wind speed/temperature/wind-chill indicator are less cumbersome than the analog devices currently available, he adds. A magnet rotates with the impeller and sensors count the number of rotations to calculate wind speed. A digital display offers settings for knots, meters per sec, kilometers per hour, miles per hour, feet per minute, and Beaufort. And users can choose between Fahrenheit and Celsius for temperature and wind chill readings.

Kestrel anemometers are waterproof and float, and come with a protective carrying case and a convenient neck lanyard. The battery is easy to replace, says Naughton, and provides 400 hours of use.

Bird Precision creates synthetic ruby and sapphire bearings in a wide variety of shapes and sizes. The company also manufactures precision orifices ranging in size from 0.0008- to 0.0350-inch that can be produced in high volumes.

Balanced power pulley fine tunes conveyor performance

Jacksonville, FL--Grocery chains are betting that automated checkout machines (ACM) will help improve front-end productivity and customer service, and reduce labor costs. To prevent ripoffs, an ACM designed by Productivity Solutions Inc. (PSI) uses a security system that validates every item's identity and physical characteristics after the customer scans the barcode. After an item is scanned, the customer places it on a belt that moves it forward through security arches. If the measured security information differs from the barcode reference data, the conveyor reverses direction, and sends the item back to the customer for a re-scan. If it checks out, the item is passed to another conveyor that moves it to a bagging station.

Two Powerroll motorized pulleys supplied by Interroll Corp. (Wilmington, NC) drive PSI's conveyors. "We recognized a potential conveyor glitch that could compromise accuracy," explains PSI's Director of Engineering Wes Dickover. "Although off-the-shelf Interroll Powerrolls were adequate for the tail-end belt, the possibility of a slightly out-of-balance pulley and the ensuing out-of-tolerance security measurements were not acceptable. A variation of one cycle per second could have a negative effect on security measurements."

"Working directly with Interroll engineers, we located the cause of the slight rotational imbalance," Dickover explains. "All that was required to correct the situation was a switch to a more uniform weight-distributed pulley tube, and a secondary honing operation on the pulley's rotor housing." Result: The balanced Powerroll meets the demands of security system electronics and provides vibration-free, accurate belt tracking, and smooth shock-free reversals on command, says PSI.

Pulley power ranges from 0.12 to 0.30 hp. Fully loaded conveyor-belt speeds are available from 21 to 245 ft/min, in standard increments.

Omron renews foundation support

Schaumburg, IL--For the seventh consecutive year, Omron Electronics Inc. is supporting the Design News Engineering Foundation with a $10,000 donation. This gift benefits engineering students at the university level.

"Omron is committed to investing in engineering education because well-trained engineers will develop the technologies that will take us into the 21^st century," says Frank Newburn, president and CEO of Omron Electronics.

Omron is one of the world's leading manufacturers and suppliers of industrial automation and control components including sensors, relays, switches, PLCs, MMIs, vision systems, RF/ID, card readers, and process controllers.

"It is through the efforts of well-trained engineers that Omron is able to develop the technologically advanced products that address its customers' demand for incorporating greater capabilities and flexibility into industrial automation and control components," comments Newburn.

In the industrial automation area, for example, Omron has developed a line of machine-vision sensors. The company says these sensors fill the gap between high-end photoelectric sensors, which cannot detect two dimensions and require adjustments as applications and/or products change; and basic vision systems that require programming and considerable setup time.

Omron is also a founding member of the Open DeviceNet Vendors Assn. (ODVA). Its industrial automation offerings include a line of motion control products; colorful, multi-vendor-compatible MMIs; PLC/PC hybrid products; and a variety of photoelectric, proximity, and optical sensors. Omron expects to release several new tactile keyswitches and specialty snap-action switches in early 1999.

"All of these developments were made possible through the efforts of Omron's R&D engineers," says Newburn, "and it is through the knowledge of well-trained engineers like these that products and technologies for the next millennium--products and technologies that ultimately benefit everyone--will be developed."

Hendrick scores four

by Rick DeMeis, Associate Editor

Charlotte, NC--When Jeff Gordon rode his stock car to the 1998 Winston Cup Championship, he certainly did it in style. He not only set or tied driver career records. But, for the first time, teams from a single car constructor--Hendrick Motorsports--have won the title four years in a row (DN 8/3/98, p. 43). Gordon, driving for a Hendrick-fielded, Dupont-sponsored team, previously won the Cup in 1995 and 1997. This string was only interrupted by Hendrick-teammate Terry Labontein 1996, at the wheel of a Kellogg's-backed machine.

The 27-year-old Gordon became the youngest driver to have three championships notched on his belt. In addition, he tied stock-car-legend "King" Richard Petty in posting 13 victories in a single season. Reminiscent of the major-league season home-run records set since Babe Ruth played, the latter mark is not without controversy. In 1975, Petty nailed his 13 in a total of 30 races, Gordon had a 33-race season, albeit in a different era.

Buy CAD while buying a workstation

St. Louis, MO--For a novel approach to buying CAD, look at the consequences of a recent agreement between Unigraphics Solutions Inc. and Dell Computer Corp. In December, Dell began offering Solid Edge, Unigraphics' midrange CAD software product, as an order-ready option for Dell Precision^TM WorkStations. The software is installed directly at the computer manufacturer's factory in Austin, TX. Customers may either purchase a full Solid Edge license through Dell at the same time they buy their workstation, or they may elect to have a 30-day evaluation copy installed and can buy the package later from a Solid Edge reseller.

"The agreement offers a convenient alternative for CAD users to very quickly obtain the productive engineering tools they need," says John Mazzola, president and CEO of Unigraphics Solutions. The Dell/Solid Edge CAD program is the latest in Dell's WorkStation Alliance Program.

"This announcement could signal a new paradigm in the way CAD software is distributed to the market," says Charles Foundyller, president of Daratech, a CAD analysis firm.