DN Staff

January 17, 2000

24 Min Read
Engineering News

Designed for danger

Albuquerque, NM--Pebble-sized robots called MARVs, or Miniature Autonomous Robotic Vehicles, may rove in packs to map a contaminated site, locate and disable land mines, or ferret out biological weapons. Or they could cut the cost of planetary exploration or perform noninvasive microsurgery.

According to Patrick Eicker, Sandia National Laboratory's director of robotics, the one-cubic-inch prototypes have successfully located and tracked signals in buried wires and followed small CO2 plumes, used to simulate biochemical hazards.

Two side-by-side sensors within each MARV feed information to an on-board computer, which makes decisions and directs the two drive motors to steer towards the target. The subsystems on the devices use MEMS technology. MARVs make control decisions--and even act cooperatively--thanks to genetic algorithm-based software, which mimics the connectivity of the human brain.

"Just as when someone suffers an accident, the brain can recover without an impaired ability to do things, MARVs can relearn how to perform a function or to communicate even when one is downed," says Eicker. "Our next step is to put them to work cleaning up contaminated waste sites," he says.

The lab aims to make the MARVs smaller for use in inspection and repair tasks in confined spaces, such as fixing broken aircraft wiring.


Titanium cuts costs

Charles J. Murray, Senior Regional Technical Editor

Denver, CO--Every engineer knows that titanium is an ideal material choice in applications calling for light weight. But you don't choose titanium to lower your costs--right?

Not necessarily, say engineers from Titanium Fabrication Corp. (Fairfield, NJ). The company recently completed construction of a giant pressure vessel for a chemical processing plant. Its material of choice? Titanium.

The firm's engineers say they selected titanium over a composite steel-and-titanium alternative for the most unlikely of reasons--cost. The key, they say, was the use of ASME pressure vessel codes that enabled them to design for higher working stresses. The titanium, which has a tensile capacity of 65 ksi, is slightly weaker in tension than the steel-titanium composite, which has a 70 ksi capacity. But because a relatively new division in the code (ASME Pressure Vessel Boiler Code, Section 8, Division 2) allowed them to use lower safety factors, the firm's engineers were able to employ solid titanium.

The pressure vessel, which is used for processing hypochlorite, needs titanium for corrosion resistance. In the past, such vessels employed steel walls with a thin layer of titanium explosively bonded to their exterior. But because explosive bonding is costly, and because the code now allows for slightly higher working stresses, solid titanium became a more cost-effective alternative in this application. "When we used the proper part of the ASME code, our engineers calculated that we could actually build this vessel more economically out of solid titanium,"notes Brent Willey, president of Titanium Fabrication Corp.

The use of titanium also enabled designers to significantly cut the mass of the pressure vessel. It measures 150 long 3 20 in diameter and weighs 242,500 lbs. A solid steel vessel might have weighed close to half a million pounds.


Snap!

Joseph Ogando, Mid-East Regional Editor

Clarkston, MI--A new electronic park-lock solenoid from Pontiac Coil Inc. does away with the fasteners that typically hold these devices together and attach them to the steering column.

What's new are the assembly's four plastic components: an override arm, a two-part case, and a disk that presses on the coil's armature pin to engage the override arm. Two snap-fit connections join the case's base and cover. Another snap fit connects the override arm and its encapsulated positioning spring to the base. All four parts are injection molded from acetal (Delrin from DuPont).

The entire assembly mounts on the steering column by means of a "twist lock," or integrated locking tabs on the base that mate with the steering column casting. Previous park-lock assemblies mounted with three screws or bolts.

Pontiac's new design also simplifies the override arm, which allows the assembly to be operated manually, replacing five parts with two, the arm itself and a positioning spring that retracts it.


New cars are bursting with Blaupunkt

Stuttgart, Germany--You'll never again hear "Are we there yet?" from those screaming kids in the rear seat, once Bosch's latest car concept reaches production.

Bosch filled a six-seat Volkswagen Sharan mini-van with all the latest electronics from its Blaupunkt division, laying in an extra 250m of wiring. The result is like standing in the middle of a home electronics store at Christmas.

The DREAMS (Digital Enlargement Automotive System) stereo weaves a 20-speaker web of sound; twin car phones are mounted on center consoles between the seats; and a video screen flashes images from the backs of all four headrests.

On the dashboard, the TravelPilot RNS 149 navigation system gives spoken driving directions as well as simple graphic arrows. This system is standard in the new Mercedes S-Class, but the next generation DX-N, which analyzes real-time traffic reports to suggest faster travel routes, won't be in production until the 2003 model year, says Claus Schmidt. He is vice president of Bosch's Systems and Modules Business in the Body Electronics division.

A test drive here showed that a car with these tools has offerings for both driver and passenger.


Cyberland

A cafe just for inventors

Chat with other inventors, ask a patent attorney a question, find groups to join, or just post questions, all at the Patent Cafe (http://www.patentcafe.com ). Users can also buy and sell patents, look for manufacturers and suppliers, and link to government agencies. The cafe features a live chat most Tuesday evenings, as well. There's also a list of inventor tool kits and software and books, even a kid's section that is fun to check out.


Robotics industry enjoys best year

Ann Arbor, MI--With nine-month orders topping record full-year marks, the North American robotics industry was on its way to enjoying its best year ever, according to new statistics released by Robotic Industries Association, the industry's trade group.

"If the industry didn't sell another robot in the last quarter, 1999 would still have been be the best year ever," says RIA's Executive Vice President Donald A. Vincent, noting that the previous record for a full year was set in 1997 when 12,149 robots valued at $1.10 billion were ordered.

Vincent attributes the record order rates to several factors, including new customers for the industry, particularly in non-automotive markets. "For example, the United States Postal Service recently announced that they ordered some $66 million worth of robots," Vincent notes. "There's also been an increase in the use of robots in industries such as food, consumer goods, and plastics, while demand from automotive manufacturers and their suppliers remains strong."

Material handling applications emerged as the leading use for robots, followed by spot welding, arc welding, assembly, material removal, coating, dispensing, and inspection.

Robot shipments also continued to rocket ahead, with 10,755 robots valued at $846.6 million shipped through September, a 32% gain in units and a 13% jump in dollar value over 1998.

From January to September 1999, a total of 13,368 robots valued at $1.11 billion had been ordered, smashing the previous year's nine-month totals by 62% in units and 40% in dollar value.

RIA estimates the U.S. robot population is approximately 98,000. According to industry analysts, less than 10% of the manufacturing companies who could benefit from robotics have installed robots, providing a huge untapped market for robot suppliers.

Vincent said that the Robotic Industries Association will launch a new initiative to reach the large base of potential users in the U.S. and abroad by creating the world's premier online robotics resource. Called "Robotics Online," it will feature an in-depth buyers guide, case studies on successful applications, updates on new products, feature articles on key issues, cutting-edge research, industry news updates, and interactive opportunities. The new site is expected to be operational early in 2000.

"The robotics industry is going to be one of the big stories of the 21st Century," Vincent said. "The technology is going to be a powerful factor in helping manufacturing companies of all sizes become more productive, and it's going to play a much more important role in areas such as space and undersea exploration, surgery, and environmental clean-up.


3D solid imaging: new star of the big screen

Burbank, CA--Computer hardware and software are stars on any movie set. Whether they're making an animated full-length feature, a two-minute cartoon, or a live-action feature film, directors use computer-produced animations for effects, "cool" cars, or characters.

Solid imaging technology is the future of 3D-product development, says Karl Meyer, president of Gentle Giant Studios. Meyer should know. His is one of the leading 3D modeling studios serving Southern California's entertainment industry, along with the toy industry that merchandises licensed entertainment products.

The company makes 3D models for numerous applications, ranging from special effects to consumer products. Recently, Gentle Giant completed more than 250 pieces of merchandise for Star Wars Episode 1. And they are working with Disney to create a digital Mickey Mouse.

To help with the complex figures and fine details, Gentle Giant studios uses Paraform (Santa Clara, CA) scanning, surfacing, and modeling software. "Paraform allows us to make more organic shapes such as cartoon figures," says Steven Chapman, technical director for the studio.

Before Paraform, Gentle Giant designers designed a model in Pro/ENGINEER from Parametric Technology Corp. (Waltham, MA), recreated the form in clay and then sent it off to China or the Far East for rendering. "And you would hope that you got something back that resembled the original design," Chapman says. "We wouldn't have attempted a lot of the designs we do today. It just wouldn't have been cost effective."

Paraform's software is surprisingly easy to use, Chapman adds. "I can watch the edges 'dance' into position. It's like watching an animation on the screen."

"Our software enables an entirely new audience to create complex computer generated models because it is so accurate and easy to use," says Venkat Krishnamurthy, CTO and co-founder of Paraform. "Designers or modelers can be up and running in an hour and into production by the end of the day."

Digital models have many benefits for Gentle Giant. There is the obvious quicker turnaround time from concept to creation because models are created in house rather than sent abroad. This process also preserves design integrity, says Chapman. And once an engineer designs a master, this model can be used for toys, movies, or video games.

Gentle Giant engineers are also pleased with how well Paraform works with their other software. In 1997, Meyer began to research 3D printing systems as a means to speed and improve productivity at the studio. After exploring the market alternatives, Gentle Giant purchased two Actua 2100 printers and the SLA 250 system from 3D Systems (Valencia, CA). "Solid imaging technology was an excellent solution for us, as we could generate models quickly and easily right in our shop," he says.

Meyer also acquired two ThermoJet printers from 3D Systems. "ThermoJet is a cost-effective 3D printer developed for CAD operators in a design-office environment," says Meyer. Much like a network printer, it uses technology that is based on ink-jet printing--but instead of ink it sprays a plastic-like substance that solidifies instantly. Within hours, a three-dimensional object is formed that can be held and evaluated. The part then becomes a real-world example of what may be difficult to comprehend when viewed as a complex CAD image on a computer screen.

Gentle Giant uses ThermoJet to augment its production process. Beginning with a hand-sculpted wax model, designers scan the model, generating a CAD file. The file can then be manipulated to create several variations of the initial object. ThermoJet is then used to print the objects, and these 3D prints serve as patterns to create molds.

Gentle Giant uses the SLA 250 for parts that need to be particularly strong and rigid right off the machine. Meyer says certain designs work particularly well on the SLA--such as thin walled parts with small details and functional prototypes.

SLA systems use stereolithography where a laser beam hardens a pool of liquid resin, layer by layer, until a solid three-dimensional object is formed.

"We're currently creating maquettes for 20th Century Fox for a feature animation movie that's scheduled to come out next year," says Meyer. "We sculpted the actual characters by hand in clay and used a 3D scanner to scan them in for later reproduction. Using the animation data, we are able to build parts on the SLA that are just perfect, while maintaining the integrity of the characters."

Flexibility and speed are the factors that Meyer cites as major benefits of integrating the technologies. "If we're working on a Buzz Lightyear figurine, and we're not sure what size the piece needs to be, we can produce a dozen different sizes and pick and choose without reconstruction," he says. "We can do mirror imaging and inverting, saving time. Sometimes it takes 50 arms to find the one that's right for a character."

"Because of this equipment, we can take on more projects, generate more product, and grow the business more effectively," Meyer concludes.


X-rays test nuclear stockpile

Los Alamos, NM--A massive x-ray machine built to photograph materials imploding at 10,000-mph speeds performed its first test in November. The Dual Axis Radiographic Hydrodynamic Test facility, or DARHT, tests the safety and reliability of the U.S. nuclear arsenal without nuclear testing. It is located at the Department of Energy's Los Alamos National Laboratory.

DARHT's experiments are called hydrodynamic tests because metals and other materials flow like liquids when driven by the high pressures and temperatures generated by the detonation of high explosives.

"Simply put, DARHT's x-rays are as key to the U.S. nuclear stockpile stewardship program as hospital x-rays are to helping to assess the health of the human body," said Energy Secretary Bill Richardson at the conclusion of the successful test.

This Los Alamos National Laboratory test facility uses sophisticated x-ray technology to determine the safety and reliability of nuclear weapons without nuclear testing.

DARHT replicates what occurs in a real nuclear weapon when the primary stage implodes. In a complete weapon, the primary stage acts as the trigger for the nuclear explosion. The facility generates a beam of power equivalent to 20,000 chest x-rays. With five foot-thick, specially reinforced concrete walls, DARHT can handle explosive loads equal to 150 lbs of TNT.

The facility can also be used to conduct shock physics, high-velocity impacts, and materials and high-explosives science experiments.


Software speeds light rail design

Osaka, Japan--Engineers at The Kinki Sharyo Co. Ltd. designed a new low-floor light rail vehicle (LRV) for New Jersey Transit using a "pile-up" technique and CSA/NASTRAN from CSAR (Computerized Structural Analysis and Research Corp.; Agoura Hills, CA). A prototype features three car sections with double articulations and three trucks on one vehicle.

The pile-up method of design classifies the items to be analyzed into three categories: local member analysis, substructure analysis, and whole car-body structure analysis.

Jun Kashima, engineering manager in charge of the NJT project car-body structure, says that local part analysis includes part design with detailed stress models. Substructure analysis includes medium assembly with reduced dynamic models for up to a quarter vehicle. And the whole car-body structure analysis involves the full assembly with heavily reduced models for check of the overall design.

In this case, after engineers proved the part design, it was used to create the whole car body for analysis and the medium assembly was skipped. This reduced analysis time substantially. "Because of the high performance of the CSA/ NASTRAN system, we did not need to analyze some local members as separated items," said Kashima. "Instead, they were included as a part of the substructure analyses because we could actually treat the local member model with a fine mesh in the substructure and whole car body analysis."

Local members included the body bolster, collision post, corner post, windshield, anti-climber, side sill, jacking pad, and floor construction. Substructures included the end underframe, high-low step underframe, and articulation arm. The whole car-body structures included the quarter-car body model, a half-car body model, and an entire-car body model. The analysis progressed from local member to whole car body.

"As a result of the pile-up method, a lot of time was saved," said Kashima. "Because local strength had already been determined, when we analyzed the substructure and whole car body, there was no need to redo local member analysis." Also some analysis items could be omitted as these were decided based on the performance of local member analysis.

Engineers used CSA/NASTRAN from CSAR to perform simulation and load analyses on this finite element model of the train.

The company acquired CSA/ NASTRAN to help with the "pile-up" technique. The program that Kinki Sharyo had been using was unable to handle the large number of nodes required to prove the NJT design. Plus, the additional time and high cost of subcontracting the design analysis was unsatisfactory. Both CSA/NASTRAN for the PC and the hardware were purchased for about one-half the cost of outsourcing the analysis work.

"We were able to solve a 10,000 node finite element model in 20 minutes with CSA/NASTRAN for the PC," says Kashima. "Our previous NASTRAN (program) could handle only a limited number of nodes and required one night to solve the same FE model."

Engineers used both simulation and load tests to check the NJT project. All strength analyses of the structure, such as static analysis and eigen-value analysis (except crash analysis), were performed with CSA/NASTRAN on a Gateway 2000 G6-200 computer with 128 Mbytes SDRAM and a 10-Gbyte hard drive.

The bundled FEMAP processor from SDRC (Milford, OH) and the CSA/NASTRAN solver operate together seamlessly, but they can also act separately. This versatility enables additional data to manually be put into CSA/NASTRAN and then be automatically output through the FEMAP processor. "By using a text editor, we were able to combine many finite element models into one," says Kashima.

He continues, "But the most impressive advantage is the time-savings to solve a huge finite element model. CSA/ NASTRAN solved a model with 71,000 nodes in only 150 minutes. We are convinced that huge FEA models can be solved, even on our PC systems. We have been working hard for flawless analysis of export rail vehicles, and by using CSA/NASTRAN for the PC, we are proceeding successfully. The NJT low-floor LRV prototype project came in under budget and on time."


Advanced glazing can save lives

Detroit--There's no doubt that seatbelts save lives. So can advanced automotive glazing systems, according to a recent study conducted by the National Highway Traffic Safety Administration (NHTSA).

In an updated status report entitled "Ejection Mitigation Using Advanced Glazing," the administration estimates that advanced glazing systems for front side windows could save between 500 and 1,300 lives each year by keeping people inside a car during rollovers.

The new study evaluated four types of glazing that go a step beyond traditional tempered glass side windows: a non-HPR ("high penetration resistant") trilaminate with two glass plies surrounding a layer of PVB film; an HPR trilaminate with a different PVB formulation; a bilaminate glazing that consists of a tempered glass outer layer and a co-extruded polymer inner layer; and a polycarbonate glazing that's thermoformed to match the curvature of a standard glass part. The tests took place on prototype window and door frames modified to improve the encapsulation of the advanced glazings. The report, however, did not delve into how much of the occupant-retention benefit can be attributed to the door and window channel modifications alone.

To measure the retention capability of the advanced windows, the NHTSA used a guided 40-lb impactor moving at 15 mph. "The results show that all but the non-HPR trilaminate had good potential for providing occupant retention."

The study also examined the potential for head injuries associated with each glazing type in a free-motion headform test, noting that the potential is higher for glass that does not fracture upon impact. "Impacts into the advanced glazing produced similar potential for head injuries as impacts using the current, tempered glass side windows," the report found.

It's worth noting that the life-saving potential of better glazing would take on less importance if more people wore their seatbelts. "In fact, 98% of occupants completely ejected and killed during rollover crashes were unbelted," the report states.


Tie-down stud simplifies wire installation

John Lewis, Northeast Technical Editor

Milwaukee, WI--What's an engineer's best defense against malfunctions due to wire-harness interference with sensitive components in industrial enclosures, heavy-duty construction equipment, and switching boxes? The lowly fastener. Familiar methods to secure wires in such applications include adhesive stick-on pads, drilling and tapping, or TIG and MIG welding. But more engineers are opting for Wire Tie Down Studs, the latest wire-tie-down-harnessing system from Wood Dale, IL-based Image Industries. In fact, because Wire Tie Down Studs offer greater endurance in extreme environments, easier installation, reduced maintenance, and a more pleasing and aesthetic appearance, Radyne Corp., an induction-heating equipment manufacturer, now uses them in its industrial enclosures.

Wire Tie Down Studs simplify wire installation and maintenance in industrial enclosures, heavy-duty construction equipment, and switching boxes.

Used in rigorous applications such as hardening, tempering, and brazing, Radyne's induction-heating enclosures need a wire-maintenance system that endures a variety of environments without weakening. Exposed daily to extreme temperatures, the enclosures must meet high industry standards. In the past, Radyne used several common wire-harnessing methods to secure wires within their enclosures. However, each of these methods proved either tedious or unreliable.

For example, adhesive stick-on pads require continuous service and replacement because oil, residue, and humidity break down the glue, causing the pads to fall off. Likewise, drilling and tapping fail to produce satisfactory results due to a laborious screw-fastening process, which is not only time consuming but leaves an unattractive surface appearance. A third method, TIG and MIG welding, requires a very lengthy and unwieldy hand-welding process.

"Keeping wires where you want them was cumbersome at best," says Radyne President John Hooper. "We tried to innovate as much as possible, and adapt new technologies as needed. But previous wire tie-down systems didn't offer the reliability we needed to keep our wires from falling down, and didn't equal the quality that's built into the rest of our product."

While Radyne was struggling with its previous harness systems, Image Industries, Radyne's existing stud-welding supplier, identified the problem and introduced Radyne to a new Wire Tie Down Stud product that eliminates a lengthy assembly process by reducing the number of components needed to secure wires." Wire Tie Down Studs, designed specifically for quick and rugged wire security, hold wire bundles up to one-inch in diameter and have a pull-off force that exceeds that of a typical 3/16-inch nylon strap. "The studs eliminate the need for screwing and drilling holes, because they are welded into place to create a secure installation that will not break, loosen, or weaken over time," says Image Sales Representative, Jack Koepke.

Unlike traditional wire fastening methods, Images' studs are not labor intensive, but quick and easy to install. After initial set-up, they can be mounted within seconds using the following procedure:

  • Insert stud extension in the welding gun

  • Place gun against the desired work surface

  • Pull the gun's trigger, then remove gun from attached stud

  • Break off stud extension with a pair of pliers

  • Secure wires with nylon tie down

Image performed several demonstrations of Wire Tie Down Studs with pressure tests, convincing Radyne that its wire harnessing method achieved the desired results. "It is obviously a better product. It never falls off," says Radyne's Senior Assembly Manager Roger Pierson.

Wire Tie Down Studs now serve as an efficient and durable solution to Radyne's wire management needs. Since turning to the system, Radyne has achieved a drastic improvement in its wire management capabilities. "We never have to replace them," says Pierson. "And they look more aesthetically pleasing because the stud fixtures appear only on the inside of an enclosure."


Software translates programs between NT- and CE-based controllers

John Lewis, Northeast Technical Editor

Freemont, CA-When adapting equipment for special applications, machine builders using a common and scalable control platform have the advantage. Without control consistency across both high- and low-end machines, efficient programming is more challenging.

That's why ULTRA t Equipment Co., a manufacturer of semiconductor equipment for companies such as IBM, Hewlett- Packard, and Motorola, is now standardizing controls via a PC-based architecture that uses Think & Do software as a universal motion program translator between Windows NT- and Windows CE-based controllers.

Think & Do Software is a PC-based control package that offers flowchart logic, HMI, motion, and serial communications. It allows programmers to develop complete programs, and then select either a Windows NT-based PC or a Windows CE platform as the target hardware.

Ultra t President John Flaagan reports that the Think & Do software, I/O, and control hardware purchased from Automationdirect.com provide a fully scalable control solution. "Using Think & Do software at both the Windows NT level and Windows CE level provides a common control platform across our entire product line."

ULTRA t builds equipment for cleaning, chemical mixing, and photoresist processing in the manufacture of products such as semiconductor wafers and flat panel displays. "We build machines that range from simple stand-alone units that are loaded and unloaded by an operator to fully automatic robotic systems arranged as groups or clusters of the stand-alone machines," Flaagan explains.

Since the price and performance requirements of its machines vary by application, ULTRA t's previous control solutions didn't use standardized components. "Because of different control-system performance requirements and cost constraints," says Flaagan, "our previous control solutions used PLCs at the low end, and sophisticated motion control at the top end.

ULTRA t selected the WinPLC, a Windows CE-based embedded PC processor that resides in a DirectLOGIC 205 PLC rack. This processor provides backplane communication to I/O, onboard Ethernet, and serial ports, and supports standard Windows communication tools such as DCOM and OPC.

Through the Ethernet port, the WinPLC communicates to both WinPLC controllers, and NT-based master stations. The WinPLC allowed ULTRA t to implement its low-end control solution at a competitive price, according to Flaagan, while keeping the same software and programming environment for its larger Windows NT-based systems.

"The WinPLC allows us to use much of the same flowchart logic on a small manual machine that we use on our more sophisticated machines," says Flaagan. "We even have the option of moving to a distributed control architecture with a Window NT-based master station and Windows CE-based distributed control. As a machinery builder, we often have to customize our machinery to meet special application needs. With common software for the NT and CE platforms, it's a lot easier now that we have a common and scalable control solution."

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