The separation of rugged from mil-spec computers continues as military program managers demand the performance and price of commercial equipment, while flat-panel displays start chipping away at the cathode ray tube`s share of the military market
By John McHale
The 1994 commercial- off-the-shelf (COTS) initiative of former U.S. Defense Secretary William Perry continues to create a gap between the Defense Department`s MIL-STD specifications and the so-called "rugged" class of products. Designers and buyers of military equipment still prefer equipment and components that meet military specifications, but are willing to loosen their environmental constraints to embrace the technology offered by commercial vendors in a rugged rather than MIL-STD package.
Officials at some military programs are even changing their specifications to enable the purchase of COTS equipment. For example, U.S. Air Force officials changed the temperature requirements for the Airborne Warning and Control System aircraft from the -40 to 85 degrees Celsius range to a 0 to 50 C range to broaden their use of COTS equipment. Technicians at the Air Force Electronics Systems Center at Hanscom Air Force Base in Lexington, Mass., determined that in 20 years of operation the aircraft operated in extreme temperatures so rarely that constraints were not necessary.
The customer continues to define ruggedness of a system when he provides the manufacturer with his specifications, says John Cochran vice president of business development at Miltope Corp. in Boulder, Colo. That same customer continues to demand the performance of equipment that does not meet military standards, he says.
Many define rugged electronics as that which can survive in harsh environments. This definition separates it from electronics for the typical commercial desktop environment, says Gorky Chin, vice president of advanced technology at Vista Controls Corp. in Santa Clarita, Calif. Rugged electronics do not have to meet military specifications and have rarely done so over the last few years, he explains.
The COTS initiative has also caused many suppliers to eliminate their military components business due to low profits, he says. Vista engineers still produce a level of mil-spec, but not without difficulty, Chin says. Building mil-spec components and subsystems is increasingly difficult because of the low availability of mil-spec parts, Chin explains. Unfortunately, the shortage in suppliers has caused Vista officials to raise the price on mil-spec products, he says. Vista has one military-grade applications specific integrated circuit ASIC supplier that has "raised prices 900 percent over the last five years," Chin adds.
Vista engineers build rugged computers and displays for the Saudi armored combat vehicles, rugged VME boards for the Teledyne Ryan Global Hawk high-endurance unmanned aerial vehicle, and many other rugged board- and subsystem-level electronics.
Miltope officials offer a commercial Intel architecture in their Prowler, a rugged portable computer chosen by ManTech Systems in Chantilly, Va., to serve as the instrument controller for the U.S. Marine Corps` Third Echelon Test Set program.
"Customers do not want to pay for the extra documentation that goes with purchasing mil-spec parts," says Richard Jaenicke, director of marketing at Sky Computers in Chelmsford, Mass. They want high performance and rugged features for a lower price, he says.
Sky`s multiprocessor SKYchannel system, which includes 32 Excalibur digital signal processors, boasts of high performance and relatively low off-the-shelf prices, Sky officials claim. The system currently provides the airborne processing power for the Foliage Penetrating Radar Program, designed by engineers at Lockheed Martin Tactical Defense Systems in Goodyear, Ariz.
"Mil-standard has become a niche within rugged," says Ken Tomkinson, DSP and graphics business manager at Radstone Technology in Towcester, England. Many environments such as space require rugged components but have nothing to do with the military, Tomkinson says.
One in 10 of Radstone`s customers uses parts that meet MIL-STD 883, while eight in 10 are military customers, he points out.
Radstone officials provide five classifications for rugged components, which they call build level standards:
1) Standard: The first classification is commercial grade, cooled by blown air; for cost-effective development in a wide range of benign environment applications and operating temperature range of 0 to 55 C with 300 foot-per-minute airflow.
2) Extended temperature: Radstone`s second classification is similar to Standard but conformally coated and temperature- characterized with an operating temperature range of -20 to 65 C with 300 foot-per-minute airflow.
3) Rugged air cooled: This classification provides operating temperature range of -40 to 75 C with 300 foot-per-minute airflow rugged, cooled by blown air, conformally coated for additional protection, and has optional environmental stress screening.
4) Rugged conduction cooled: Mechanically compliant with IEEE 1101.2-1992, the fourth rugged classification was designed for severe-environment applications with high levels of shock and vibration, small space envelope and restricted cooling, and optional environmental stress screening and an operating temperature range of -40 to 75 C.
5) Rugged conduction cooled: The last classification is the same as 4, but has an operating temperature range of -40 to 85 C.
Engineers at Northrop Grumman in Rolling Meadows, Ill., chose Radstone`s VSP-1 vector digital signal processor board to re-engineer the radar signal processing system of the U.S. Army`s AN/TPQ-36 and AN/TPQ-37 Firefinder radar.
Radstone teamed with Sky Computers - using a commercially-developed Sky product called Skybolt Shamrock 6U VME DSP board - to redesign the vector signal processor in the Firefinder`s operator control group, which provides the computer power for radar signal processing and other functions that control the radar.
The redesign included engineering design practices such as thermal, electrical, and mechanical derating. Engineers selected wide-temperature, -55 to 125 C mil-spec components, then de-rated the components to operate at a maximum temperature of 105 C. Minimizing drive currents and reducing maximum frequency operation on individual components were other measures.
A system is technically rugged if it meets military standards for shock and vibration, but also environmental sealing, says Vincent Dipas, communications manager at FieldWorks in Eden Prairie, Minn. Engineers need to meet these specifications for high-end applications, Dipas says.
Officials at the Naval Surface Warfare Center`s Crane Division in Crane, Ind., agreed with Dipas and chose the FieldWorks FW7000 rugged, expandable workstation as the computer platform for the AN/PSM-93(V), a self-contained computer test set that performs testing, repair, and maintenance of shipboard electronics equipment.
Designed as a configurable laptop workstation with six ISA/PCI expansion slots, the new FW7000 series offers a 200 MHz Pentium processor and is forward compatible with higher-performing processors. Older Pentium 7000s can be upgraded to 200 MHz.
Dipas warned that rugged products should not steer too far from military standards or end up failing in harsh environments.
Customers of Dolch Computers in Fremont, Calif., do not need their equipment to survive in extreme environments, says Ken Price, marketing manager for Dolch. They demand an industrial type of rugged that would not work in mission-critical applications but performs well in controlled areas, such as field transportation, he says.
Dolch experts offer their customers the FieldPAC portable computer, designed to withstand the rigors of transport, setup, and operation in rugged environments. Designers encase the device in a deep-drawn, corrosion-proof aluminum enclosure, with an upgradeable Pentium MMX computer module mated to a 14.1-inch XGA thin-film-transistor (TFT) display. Expansion features include a user definable full-size ISA or PCI expansion slot is provided, and two standard PCMCIA/CardBus slots.
Military customers want a controlled set of environmental specs for combat situations, says Chris Marzilli, director of commercial hardware systems at the Communications Systems Division of GTE Government Systems Corp. in Taunton, Mass. Despite the push for less money, they still want a system that will not fail, he says.
GTE is the prime contractor for the U.S. Army`s Common Hardware Software Program, Common Hardware Software-2 (CHS-2), with Sun Microsystems in Mountain View, Calif. Both companies are providing the workstations and servers. The program provides common hardware, peripherals, and software for the Army Battlefield Command Systems`s Battlefield Functional Area Control Systems - maneuver control, fire support, combat service support, intelligence/electronic warfare, and air defense.
Among the programs "we`re involved in we`re not seeing any mil-spec," says Gary Olin, director of corporate marketing at Mercury Computers in Chelmsford, Mass. Some defense programs will still demand mil-spec parts for mission-critical applications, but the low price of systems made up of ruggedized commercial technology is too good for most customers to pass up, he says.
"We designed our processor with rugged in mind," Olin says. Mercury products are ruggedized at the design level through highly accelerated life testing and highly accelerated stress testing - better known as HALT and HAST - which puts systems through ruggedized tests beginning at the component level, he explains.
Mercury`s RACE computer systems will be part of the U.S. Army`s Predator Medium Altitude Endurance Unmanned Aerial Vehicle designed by engineers at Northrop Grumman Electronic Sensors and Systems Division in Baltimore. Mercury will provide 23 multicomputer systems for deployment aboard Predator aircraft as part of Northrop Grumman`s Tactical Endurance Synthetic Aperture Radar (TESAR) system.
TESAR is a lightweight, low-cost surveillance radar that works with an associated ground station to produce photographic-quality radar imagery with one-foot resolution. Its onboard RACE computer system performs processing on the radar signals before the resulting data is downlinked to the ground station.
"Mercury is well suited for these applications, because our RACE computers provide a small-footprint, low-power system that can tolerate the motion and vibration aboard the Predator while performing sophisticated digital signal processing on an uninterruptable data stream throughout missions lasting up to 40 hours," says Jay Bertelli, president and chief executive officer of Mercury.
Officials at Solaris Systems in Anaheim, Calif., are not seeing much market attention toward mil-std products, says Jim Foti, vice president of business development at Solaris Systems. However, there is a lot of interest in commercial technology such as SPARC-based and Intel-based products out there, which in a non-mil-std package comes at a low price, he says.
Solaris engineers offer a family of rugged SPARC-based servers and workstations for deployed mobile, and tracked Mil- E-4158, shipboard Mil-Std-2036, airborne Mil-E-5400 applications, and are designed to meet EMI/RFI requirements.
"A customer wants to have something that fits their needs and it almost always is modified COTS," says Maury Kolelemay, manager of strategic marketing at Codar in Longmont, Col. Modified COTS is when engineers take commercial parts and make a rugged system out of them, he says.
Codar engineers are ruggedizing the commercial-off-the-shelf equipment of Sun Microsystems for the CHS-2 program.
COTS absolutely is the way of the world the last couple of years due to the dominance of "Wintel solutions in the marketplace," Miltope`s Cochran says.
Not only has COTS changed the way designers look at the rugged standard, but the fast pace at which commercial tech- nology becomes obsolete pushes designers to include technology insertion in all their systems, he adds.
Technology becomes obsolete in 18 months to three years, Kolelemay says. Technology insertion is the best way to swap out obsolete peripheral components, he says.
The military used to require that systems last at least 20 years, says Duncan Young director of marketing at DY 4 Systems Inc. in Kanata, Ontario. Today most systems are expected to have at least a 10-year life cycle, which is still a long time for most commercial technologies and is why providing easy upgradeability in a product is so important, he says.
DY 4 engineers provide flexible I/O expansion in their SVME/DMV-177 PowerPC 603e single board computer, which operates at 200 MHz, has 64 Megabytes of DRAM with EDAC, VME64 master/slave interface, and is available in a range of ruggedization levels - air and conduction cooled.
Designers must pay close attention to open architecture and do insertion through open packaging, Kolelemay adds. Engineers must also design software that is compatible with older technology, he says.
Designing for technology insertion comes down to logistics, finding the cheapest way to upgrade, Kolelemay continues.
Within three years Pentiums go from 100 MHz to 200 MHz, Dipas says. "Customers want the latest and greatest technology in a rugged system and we offer that with plug and play features" such as the four expansion bays on the FW7000, he adds. A problem with upgrading older technology such as the I860 to a PowerPC is porting the old code to the new hardware, says Sky`s Jaenicke. Going from a 200 MHz PowerPC to a 300 MHz PowerPC is easy, he adds.
Displays
The push towards commercial technology has also paved the way for flat-panel displays to enter the military market.
Military designers are beginning to recognize that flat-panel displays are lighter and cheaper than cathode ray tube devices, says Dennis Ogle, Army program manager at Litton Data Systems in San Diego. Flat-panel devices have proved themselves in the commercial market and the military is the next logical step, he says.
Litton`s Hand-held terminal unit (HTU) is part of the CHS-2 contract, and is intended for rugged field environments. The HTU is based on a 133 MHz Pentium micro- processor with 16 to 32 megabytes of RAM, a 7.4-inch monochrome or a 7.8-inch- diagonal color flat-panel display, and weighs three pounds. It uses a rugged keyboard and its display is sunlight readable with an operating temperature range of -25 to 49 C.
Liquid crystal displays (LCDs) are popular as well but crack in extremely cold temperatures, says Gary Lufriu, president of Science Applications International Corporation (SAIC) in Washington. The displays also require constant power, he says.
SAIC officials offer their military customers a device for temperatures above -20 C with the Rugged Merlin 16.1-inch flat-panel display, which passes MIL-STD-901D environmental shock testing. SAIC engineers designed the Rugged Merlin to meet the harsh environmental requirements of combat ships and submarines, armored vehicles, aircraft, and industrial display applications.
"The display remained operational throughout the intensive shock testing despite the fact that it was not protected by any resilient shock-absorbing devices," Lufriu claims. "It sustained severe blows while it was hard-mounted on a wall plate attached to the test fixture. I know of no other 16.1-inch flat-panel display which has endured the shock testing and continued to operate."
The Rugged Merlin is a high-resolution viewable, active-matrix off-the-shelf LCD that SAIC designers have repackaged and enhanced to pass the shock tests. The color display, which achieves resolutions as fine as 1,280 by 1,024 pixels, features adjustable viewing angles, reduced weight, low power consumption, and flexible rack space utilization. It is available in configurations such as wall mount, equipment rack mount, tray rack mount with vertical tilt, desktop mount, touchscreen, and other options.
Touchscreen flat-panel devices also eliminate the need for a keyboard and are part of the push toward voice recognition technology, Lufriu says.
Soldiers must have their hands free when working in the field, and these technologies can provide that, says Pat Wilson, vice president of sales at the Phoenix Group Inc. in Hauppauge, N.Y.
All Phoenix systems have speech recognition and audio play, Wilson says. The systems use voice recognition software and an earbone microwave receiver, she adds. An earbone microwave receiver is set in the ear and transmits the vibrations of the voice box to the computer, Wilson says.
The big problems with voice recognition is getting software that works and making sure that it holds up in stressful conditions such as battle where a soldier`s voice may change tone based on his stress, Ogal points out.
Voice recognition software companies include Verbex Voice Recognition System in Edison, N.J., and ITT in San Diego, Wilson says. ITT engineers are working on a voice-recognition technology that performs well in high ambient stress environment, she adds.
Other solutions are rugged keyboards that keep out dust and moisture, GTE`s Marzilli says. Plastic shield or ruggedized components protect the keyboards, he says.
Power use
The trend in battery technology for displays still leans toward rechargeable lithium ion devices, Marzilli says. If a display is in open sunlight or protected in a shelter it still needs a sleep mode to conserve power, he says.
Displays that do not use a reflective technology need the extra power to boost the backlight for sunlight readability, says Phoenix`s Wilson. Phoenix uses a proprietary reflective scheme that enables users to read the screen in complete sunlight without any drain on power, she adds. Reflective technology results in low cost due low power requirements, she says.
Rugged offerings
Engineers at SBS Microalliance in Vista, Calif., offer the Model 904, a portable Intel Pentium computer system designed for harsh transit conditions. The rugged unit is for use in industrial, data collection, mobile field testing, and computer telephony applications where a powerful portable computer is necessary.
The 904 weighs 19 pounds and comes with a 10.4-inch active-matrix thin-film-transistor color flat-panel LCD that gets protection from a Lexan shield. It includes a 200 MHz Pentium-based plug-in processor card with 16 megabytes of RAM.
Engineers at RDI Computer Corp. in Carlsbad, Calif., offer the UltraBook portable UNIX workstation. It has full compatibility with a Sun Ultra 1 desktop in a light, compact, and affordable package, RDI officials say. UltraBook has the same 200 MHz and 167 MHz UltraSPARC chip set used in Sun workstations.
For rugged environments, engineers at Cetia in Cambridge, Mass., offer the Ruggedizer, a board-level stiffener and heat sink. Meanwhile, engineers at SBS GreenSpring Modular I/O of Menlo Park, Calif., and DY 4 have joined hands to bring the first conduction-cooled IndustryPack (IP) mezzanine cards to harsh-environment systems designers.
The new DY 4 IP modules will maintain 100 percent software compatibility with SBS GreenSpring`s new VME64x compliant VIPC664 quad carrier board and several selected GreenSpring IndustryPack modules, preserving customers` investments in deployable system software, DY 4 officials say. The IP modules also require little power, which is an advantage in rugged systems, DY 4`s Young says.
Engineers at Greco Systems in El Cajon, Calif., designed the RCS 10000 rugged 586 PC. The device is engineered, tested, and certified to MIL-STD 810E and TEMPEST LEVEL II. The Greco computer is designed to prevent the escape of electromagnetic emissions and has an auto-seeking power supply to draw power from any AC or DC source.
Experts at Computer Dynamics in Greenville, S.C., have released the Survivor, a sunlight-readable 200MHz Pentium MMX computer. The survivor comes with a 13.8-inch XGA liquid crystal display with an infrared touchscreen housed in a rugged enclosure and rated for an operating temperature range of -30 to 45 C.
The hand-held terminal unit from Litton Data Systems was chosen for the U.S. Army`s Common Hardware Software Program, Common Hardware Software-2.
The Ruggedizer, designed by engineers at Cetia is a board level heat sink designed to lower the overall operating temperature of a board, while adding mechanical stiffening and protection.
Engineers at SBS GreenSpring Modular I/O and DY 4 have designed the first conduction-cooled IndustryPack modules for harsh environments.
Rugged computers not just for the military
The success of rugged off-the-shelf computer products has sparked an interest among systems designers outside the military such as the industrial and medical fields.
The COTS initiative has brought the prices of these systems down, says Vincent Dipas, communications manager at FieldWorks in Eden Prairie, Minn. Before COTS, rugged systems with military-standard requirements were too costly for most of the commercial sector, he says. "Our customers in this area have even expanded to include telemedicine and telejournalism," he adds.
Both industries have people on the move in extreme environments throughout the world and need equipment that will not fail, he says. FieldWorks has a contract with television networks CNN and CBS to use the FieldWorks`s FW7000 series for a portable computer for reporters at remote sites across the globe. The system puts the whole TV truck in one package that one person can carry and operate, Dipas explains.
A team of explorers and physicians from Yale University in New Haven, Conn., are also performing the first-ever telemedicine on mountaineers climbing Mount Everest in Nepal, using FW7000 Series systems specifically configured for medical data acquisition and transmission.
The FW7000 is a configurable laptop workstation with six ISA/PCI expansion slots and comes with a 200-MHz Pentium processor. The device is forward compatible with higher-performing processors.
FieldWorks portable computers are also finding a niche in oil refineries, Dipas adds.
The oil market requires equipment that meets similar extended-temperature requirements as telemedicine, telejournalism, or even some military applications, says Chris Marzilli, director of computer systems at GTE Computer Systems in Taunton, Mass.
Yet potential users must make a distinction between industrial and extreme, unstable environments, says Maury Kolelemay, manager of strategic marketing at Codar in Longmont, Col. Many industrial applications that are in places such as a steel mill are stable environments and do not require a military-standard device, he explains. "While a steel mill is hot and dusty all the time, the temperature is constant," Kolelemay adds.
A military device could be in Alaska in a cold environment one day, in a desert the next, and dealing with electromagnetic interference the day after that, Kolelemay says. Environments other than the military that require these types of systems are gas and oil exploration and possibly strip mining, he says.
Codar engineers offer rugged performance with their Explorer II lightweight portable computer. The device supports SPARC 5, SPARC 20, and UltraSparc processors, has single-, dual-, and quad-processor configurations, a 12- or 13-inch color active-matrix display with resolutions of 1,024 by 768 pixels or 1,280 by 1,024 pixels, an integral CD-ROM option, and Sun Type 5 environmentally-sealed detachable keyboard with an integral pointing device.
Emergency medical technicians and police need a portable computer that can survive the stress of rough road conditions, and most importantly not fail in a life-critical situation, says Pat Wilson vice president of sales at the Phoenix Group Inc. in Hauppauge, N.Y. Phoenix`s business is about 70 percent military and 30 percent commercial, Wilson says.
Wilson`s engineers designed the rugged tablet-style Nightingale portable computer for use in harsh outdoor field applications requiring high levels of resistance when operating in contaminated environments such as chemicals, gas, diesel fuel, and saline solutions.
Features include a built-in sound card that enables voice recognition as well as audio record/playback capability. The built-in mouse/touchscreen - using the Phoenix passive pen or finger - enables touch command screen capability for menu-driven applications. The optional 2.4 GHz spread spectrum frequency hopping wireless LAN radio link provides Ethernet compatibility at 1 megabit per second. The Nightingale will endure a three-foot table drop and operate over a temperature range from -25 to 55 degrees Celsius in addition to its resistance to sand, dust and rain.
Phoenix`s portable computers are not laptops or notebooks; soldiers need to have their hands free and still be able to use the device, she says. It needs to be lightweight and rugged for high-stress environments, Wilson adds.
Phoenix also offers the Super Nightingale, which features the industry`s only battery-powered color sunlight-readable 640-by-480-pixel VGA display with greater than 1,000 NITS of brightness, Phoenix officials claim. The display consumes 10 watts of power and offers portable field or vehicle use when operated from its internal removable batteries. The two removable rechargeable Lithium Ion batteries are resident in the unit and may be hot swapped.
The high-resolution touch screen, - 1,024 by 1,024 dots per inch - enables a passive pen or a finger to input data as well as provides for hand- writing-recognition capability. An optional active-pen touch screen is available with a resolution of 2,048 by 2,048 pixels.
The standard Super Nightingale includes a built-in 16 bit SoundBlaster card, microphone, and speaker. It also contains provisions for an optional detachable keyboard that may be backlit for nighttime use. Custom sealed doghouses are available that protect the PCMCIA slots from the environment. This water-resistant unit can be operated over a temperature range of -18 to 55 C. - J.M.
The rugged tablet-style Nightingale portable computer from the Phoenix Group Inc. is targeted at harsh outdoor field applications requiring high levels of resistance when operating in contaminated environments such as chemicals, gas, diesel fuel, and saline solutions.
Systems integrators demand low-cost rugged equipment
Electronic systems integrators in the military and aerospace business demand the latest and greatest commercial tech-nology in an inexpensive package. This creates substantial design challenges for designers of rugged components and subsystems.
Customers want the same level of performance out of a non-rugged system, and want it faster and cheaper, says John Bratton, product manager at Vero Electronics in Wallingford, Conn. The trick with COTS is ruggedizing a commercial part inexpens-ively, he says.
Vero engineers provide rugged protection with their heavy-duty card frame, the HD-167. They built the HD-167 to meet MIL-STD-167. It uses the EUROCARD format, and houses VME, VXI, and MULTIBUS boards. HD-167 frames are suitable for military and industrial applications in which users encounter severe environments including shock and vibration. Experts at the factory supply each frame and assemble them to customer specification.
Individual front panels for printed circuit boards add rigidity, aid in directing airflow, assist in board extraction, and provide some EMI shielding. The HD-167 subrack`s front panels are conductively finished and when inserted, are electrically coupled to the card frame.
Customers want a magic box that can hold normal commercial equipment operating under normal commercial temperatures and still survive in a harsh environment, says Gorky Chin, vice president of advanced technology at Vista Controls in Santa Clarita, Calif.
They want to put a desktop PC in a box that is small enough to fit in a tank and continue to operate when the tank goes into battle, Chin says. "If this box existed "it would be the Holy Grail" of rugged computers, he adds.
Currently, desktop technology in a box small enough to fit in a tank is not feasible, he says. A VME card is slightly more feasible, Chin adds.
Vista`s 1 air transport rack short chassis currently flies on the Tier II + Global Hawk designed at Teledyne Ryan Aeronautical in San Diego. The device offers accommodation for 12 6U VME boards, 200 watt 28 VDC power supply; VME J1/J2 backplane; and front panel with MIL-type connectors configured to customer specification with an option for a fan unit or cold-plate mounting.
Most customers want resistance to shock and vibration to follow MIL-STD 810, a high level of performance, and they want it right away at a low cost, says Shan Morgan, vice president of system sales at Elma Electronics in Fremont, Calif. Packaging engineers have to come up with a way to deliver traditionally expensive rugged features at a low price, he says.
Elma has solved that by assembling the system at the component level instead of building a box around an existing system, Morgan says. The result is a $5,000 to $10,000 box instead of a $40,000 box, he says. Morgan also claims his lead time has also been cut in half from 14 weeks to between six and eight weeks.
Elma engineers offer the rugged MIL 12-R3 enclosure system for extremely harsh environments. The device provides protection from shock, vibration, temperature extremes, sand and dust, power fluctuations, and has RFI/EMI to ensure the reliable operation of as many as 20 VME cards, with as many as four disk/tape drives.
For the COTS enthusiast Elma engineers offer the rugged COTS 12R2 shock-isolated enclosure, designed for industrial and deployed applications where shock, vibration, EMC, and TEMPEST are the primary considerations. The 12R2 provides substantial cost savings where the MIL-Rugged 12R3 is not required. It retains the design flexibility of the Type 12 to accommodate a wide variety of system components. Designers can mount 6U and 9U VME cards with as many as 21 slots. Integrators can mount a variety of drives and power supplies on the platform using standard Elma mounting kits.
Engineers at Matrix Corp. in Raleigh, N.C., also provide COTS packaging with their GMO rugged enclosure for ground mobile, portable systems, and other high-shock and high-vibration applications. The device contains two main mechanical assemblies - an exterior shell for mounting and shielding and an interior subchassis that houses a VMEbus or CompactPCI card cage.
The COTS side of the market will continue to grow as the commercial technology continues to prove itself, Morgan says.
Due to fast-changing technology, packaging also needs to be backward and forward compatible, Bratton says.
"Obsolescence is not a factor with our chassis because of its modular design," Vista`s Chin says. "If one of the techn- ologies becomes obsolete, we will replace it in sections," he explains.
Engineers at Isothermal Systems Research in Clarkston, Wash., are looking to ruggedize commercial boards with liquid cooling. Isothermal officials claim their spray cooling system will increase power density, lower vibration, and lower weight in VME boards.
The spray cooling system uses the 3M liquid chemical Fluorinert to cool the boards in a closed loop system. Spray cooling removes heat 500 times more efficiently than air cooling, Isothermal officials claim. Conventional air cooled systems are limited to a power density of about 1 Watt per cubic inch, while spray cooling can handle more than 500 Watts per cubic inch, they say.
The coolant eliminates the excess vibration caused by cold-plate cooling, says R.J. Baddeley, manager of government systems at Isothermal. With cold plate cooling, vibrations are channeled through the cold plate heat sink back to the board, unlike spray cooling devices where there is no structural path to transmit vibration, he explains.
There is not a lot of test data out on Fluorinert yet, Chin says. "We are watching it closely," and if it proves successful "we will come out with product based on it," he adds.
While it is an interesting technology, there are concerns regarding maintenance of the pumps and of the filtration of the liquid, says Duncan Young, director of marketing at DY 4 Systems Inc. in Kanata, Ontario.
Another concern is if the fluid flow will remain constant in an accelerated environment such as flight or battlefield vehicles, Chin says. If the bottom of the box is flipped over when a tank goes over a hill, it may shift the box creating a new bottom, and possibly interrupting the flow of liquid, he explains. - J.M.
The rugged MIL 12-R3 enclosure system for extremely harsh environments from Elma Electronics provides protection from shock, vibration, high and low temperatures, sand and dust, power fluctuations, and is RFI/EMI shielded.
