BY John Keller
Everyone involved in the embedded computing business for aerospace and defense applications knows what is job-one: components must become smaller, lighter in weight, and must consume less power. This size, weight, and power (SWaP) issue governs the industry; no one argues with that. Modern unmanned aerial vehicle (UAV) designs, as well as sophisticated electronics that fit inside light military combat vehicles are driving the SWaP imperative.
Job-one also mandates the use of open-systems industry standards to achieve SWaP goals. Systems buyers in the U.S. Department of Defense (DOD) and other government agencies are sick of proprietary designs that lock them into specific vendors—no matter how capable or revolutionary the technology might be. SWaP and standards: these are the knowns.
The big question is how do designers achieve the kind of SWaP that customers demand? Existing generations of small embedded computing standards, such as 3U VPX and 3U CompactPCI, simply may not be small enough any longer, as systems integrators scour the industry for single-board computers that are the size of credit cards, and even smaller.
Just how industry gets to a standard new generation of the smallest single-board computers ever is where the knowns start to disappear, and the unknowns gather like dark clouds. At the source of the confusion lies a question: Does industry need another computer board standard form factor to meet future demands for smaller, lighter, and more efficient embedded computing, or are existing standards good enough?
Little industry consensus exists, and this question frames the current debate on small-form-factor embedded computing. "There is a fairly big debate in the industry right now. There is uncertainty as to what hardware they can use to solve their applications in this small-form- factor space," says Steven Edwards, chief technology officer at Curtiss-Wright Controls Embedded Computing in Ashburn, Va.
One approach involves coming up with a new industry standard, which would be under the Aegis of the VITA Open Standards, Open Markets embedded computing trade association in Fountain Hills, Ariz. VITA is sponsoring three separate initiatives to formulate a new small-form-factor industry standard, known as VITA-73, VITA-74, and VITA-75.
The idea is to create three new small-form-factor standards, and then let the market sort out which of these standards would become the most popular and dominant. Companies involved in proposing VITA-73, VITA-74, and VITA-75 standards, respectively, are PCI-Systems Inc. in Sunnyvale, Calif.; Themis Computer in Fremont, Calif.; and Curtiss-Wright Controls Embedded Computing in Ashburn, Va.
Of these three companies, Themis is perhaps the farthest along in development, and is offering boards the size of credit cards, computer systems the size of a deck of playing cares, and full embedded computer systems the size of a Rubik's Cube, explains Bill Ripley, director of business development for mission and payload systems at Themis.
Designers at Themis are trying to use existing standards as much as possible in formulating their VITA-74 proposals. "We do that to lower the risk in building this new standard by adopting pieces from other standards," Ripley explains. "We took the bus topology from 3U VPX, the FMC connector from VITA 57, and allowed the use of the nanoETXexpress form factor on carrier boards." The nanoETXexpress specification is a variation of the Com Express standard of the PCI Industrial Computer Manufacturers Group (PICMG) in Wakefield, Mass.
The Themis VITA-74 design secures circuit cards inside the chassis without the use of wedge locks. Instead, each module fits into spring-loaded heat plates in the chassis such that the cards contact the heat plates on three sides, fitting snugly in the Rubik's Cube-sized chassis.
Curtiss-Wright designers are re-evaluating their approach to a VITA-75 design, and are trying to determine what is a "good-enough" approach that would satisfy industry and government requirements at a reasonable cost, Edwards says. "We are still firmly behind VITA-75, but we are even having to go back to this push for good enough, and what that means for our plan," Edwards says. "I don't have any definitive plans now." PCI Systems, meanwhile, did not respond to inquiries for this story.
The quest for "good enough" when it comes to small-form-factor embedded computing not only is contributing to industry uncertainty, but also is driving systems designers in different directions.
"Customers are driving down their costs to us to get things done cheaper," says Jeff porter, senior system engineer at Extreme Engineering Solutions (X-ES) Inc. in Middleton, Wis. "We are really trying to push off-the-shelf, previously defined standards."
Among the standards X-ES experts use for small-form-factor embedded computing is PICMG COM Express, on which the company's XPand6000 natural convection-cooled or conduction-cooled rugged ATR chassis is based. "This is inherently intended for use in the commercial market, but there is a drive to use it for industrial and military requirements by ruggedizing COM Express for high- and low-temperature environments," Porter says.
As far as the VITA effort to formulate small-form-factor standards is concerned, Porter says there is no compelling need for a new standard—at least not yet. "We don't think the industry is large enough for new form-factor standards," Porter says. "PMC and XMC standards have commercial applications, and they are known entities. The hardware is already there, and the market will support it."
Likewise, Kontron in Poway, Calif., is banking on PICMG COM Express standards to meet customers' small-form-factor embedded computing needs. Kontron's COM Express Mini is based on nanoETXexpress. Kontron also offers Mini-ITX and Nano- ITX products, and is developing a new product called the Kontron Machine-to-Machine (KM2M), which uses a COM Express Mini module on the inside, and a small carrier card about the size of an Altoids mint box, says Christine Van de Graaf, product manager at Kontron's embedded products business unit.
"It is a very small system based on a small-form-factor carrier card and a peripheral card to serve the machine-to-machine space," primarily for communications, Van De Graaf says.