COTS systems streamline costs for military suppliers

Sept. 1, 2004
The key to making COTS work for the military is to build systems around open-standard interfaces to allow developers to capitalize on technology insertion to upgrade individual modules while maintaining backplane compatibility.

In a competitive economy, cutting costs is a way of life for most military suppliers, yet that practice can hurt rather than help if it's not done correctly. An adroit military supplier would do well to focus on the areas that are central to its strategy and then streamline its business by outsourcing the non-value-added processes to trusted partners.

Of course, outsourcing has always been an option, but because of tighter budgets and shrinking time-to-market windows, more military suppliers are taking advantage of it. When you consider that many military applications use the same basic building blocks — such as I/O interfaces, boards, and assemblies — there is little reason for a military supplier to start from scratch.

To that end, military suppliers have been purchasing basic and even complex commercial off-the-shelf (COTS) systems from companies such as SBS Technologies and then adapting the configurations to meet application-specific requirements. An excellent starting point is a basic system that includes a single-board computer (SBC), data bus, analog and discrete I/O, a power supply packaged in a rugged enclosure, and ample spares to accommodate growth. This setup can be the basis for applications that include unmanned aerial vehicles (UAVs), missile-guidance systems, ground-based or shipboard radar/sonar sensors, industrial control-and-monitoring systems, telecommunications systems, air-traffic-control systems, and even the space shuttle.

The key to making COTS work for the military is to build systems around open-standard interfaces to allow developers to capitalize on technology insertion to upgrade individual modules while maintaining backplane compatibility. This way, designers get reduced nonrecurring engineering (NRE) costs at the initial design phase. The technology insertion can usually be done without paying for the design of new modules as long as the module and associated software adheres to industry-standard bus interfaces, form factors, real-time operating systems, and application programming interfaces (APIs). This enables system upgrades and performance increases without reengineering.

Because a company like SBS can manufacture large quantities of the systems (which before modifications are essentially general-purpose systems), the cost savings can be passed on to the customer. Plus, the large user base can help uncover design defects early. The systems are generally backward compatible with legacy products and can advance with technology. What's more, the application software is not bound to a single piece of hardware/software, and there is flexibility in the hardware source code, allowing the customer to make changes.

This basic system can provide a rugged-yet-flexible COTS computing platform. It comprises three compartments: the CompactPCI (cPCI) backplane card slots, the power supply, and the external I/O connections via a printed circuit board (PCB) or cabling. The basic building blocks consist of cPCI modules that plug into a backplane PCB. The I/O routes through the backplane to an I/O PCB or flex cable via an interconnect that contains military connectors mounted to the front panel.

Designers can use the system as a starting point, adding a graphics board, discrete I/O, or high-speed serial interfaces, which enable the system to become a mission computer, a display processor, or the underpinnings of an aircraft-communications system. The I/O is usually modified for each platform and could be based on MIL-STD-1553, ARINC 429, HSS, digital and analog I/O, Fibre Channel, IEEE 1394 Fire Wire, and more. Designers make changes to the backplane and I/O printed circuit board (PCB) "relay out" to reroute customized I/O to the external interface. They can change the chassis-connector front-panel faceplates if they require different external connectors.

As technology advances, the requirements for more functionality and speed in smaller, lighter, lower-power platforms is increasing. These requirements are driving a trend in which many designers are using 3U form factors in lieu of 6U for COTS systems. This obviously reduces the footprint by half and helps to lower the weight of a system. In designing a UAV, to cite an example, designers strive to reduce the gross takeoff weight of the vehicle's internal/external "payload," as mission-flight endurance is directly proportional to weight.

For cooling, conduction is the primary means of heat transfer away from board components and through the chassis. By careful component selection, placement, and thermal conductivity between the CompactPCI modules and the chassis, the system operates at temperatures as hot as 85 degrees Celsius at the rail.

A COTS filter and power supplies from a leading manufacturer of high-reliability microelectronic power-conversion products are housed in a separate shielded plug-in module. The module slides into its own aluminum compartment, which acts as a shield, preventing possible electromagnetic-interference (EMI) emissions from radiating to the adjacent critical circuit modules.

Interestingly, SBS has found that Tier-1 and -2 military suppliers are buying a basic COTS system for one project and then using the same system (with minor modifications) for other projects. The most obvious advantage is the reduction in electrical- and mechanical-design changes, thereby minimizing NRE costs. There are also huge cost savings in software as much of the application code can be carried over. User and system integration is fairly straightforward, and upgrades are easier, saving time. Often, test peripherals and lab equipment can be reused, not to mention that because qualification tests have already been performed on earlier projects, such tests can often be waived or leveraged to satisfy new requirements.

To meet application-specific requirements, the military can also outsource acceptance and qualification by having a company such as SBS perform a comprehensive battery of tests, including shock, vibration, altitude, thermal cycles, and EMI. However, a project doesn't have to be put on hold until all the testing is complete. Often, companies can deliver an engineering development unit (EDU), basically a nonrugged system, so that work on the application software can begin while ruggedization and qualification testing is in progress. With parallel efforts, time-to-market is greatly accelerated.

Military suppliers can also request advanced services from a vendor, including design practices (based on extensive military-packaging experience), analyses to simulate qualification of thermal and vibration levels, and testing to prove system worthiness during qualification.

In short, military suppliers can purchase a basic COTS system and adapt it to meet application requirements. This kind of outsourcing, without question, saves time and money.

Dave Garcia is a program manager at SBS Technologies, a single-board computer and computer-subsystem manufacturer in Albuquerque, N.M.

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