Electronics & Computers

From VME to VPX

Over the years the focus has been on highly defined “fixed” specifications for subsystem solutions that meet SWaP (size, weight and power) constraints. It is apparent today, however, that missions change over time. Today’s platforms must be versatile and easily adaptable to handle a range of ground, sea, and airbased payloads and meet an ever expanding scope of changing mission objectives. This has led to an innovative approach that leverages flexible subsystem modules to introduce new technologies to deployed assets. This modular, or building block, approach allows scalable architectures to be planned into future systems and significantly alleviates the constraints of creating new platforms for future needs.

As deployed systems began to migrate from VME to VPX-based embedded computing subsystem solutions, another significant obstacle appeared. While processing speeds and compute density have grown exponentially, the available space, weight and power on the platforms remained constant or was reduced. To that end, the increases in speed and computing density provided opportunities for system consolidation. However, in many cases, the power requirements of a VPX module are two to four times greater than that of a legacy VME module (Figure 2). All of this additional thermal energy must be addressed, without increasing the size or weight of the system.

One solution to these issues is combining flexible open standards, such as VPXbased open architecture, with cutting-edge high reliability packaging solutions. This combination provides the leveragability and capabilities needed in today’s rugged high performance embedded computing market. By embracing scalable open standards- based solutions, the lead time and costs associated with bringing new technologies to market are reduced while scalability and portability are increased. New technologies are changing the potential scope of a project. For example, Mercury’s Air Flow-By™ (AFB) cooling techniques for VITA 48.7/48.1 circuit card assemblies reduce module weight by more than 20 percent, reduce the power of a typical system by greater than 5 percent, and improve the MTBF by five times.

Another trend is the deployment of computational subsystems into a much wider range of uses; for instance, the same subsystem may be deployed on an unmanned aerial vehicle (UAV), a shipbased system, or ground station. The goal is to produce subsystems that are defined by the capability that they provide rather than the platform they were developed for. Accordingly, subsystems must be highly reconfigurable and offer a wide range of modular and scalable capabilities. Although there are a number of challenges in developing these scalable platforms, the product velocity and risk reduction through reuse are attractive incentives for standardizing the computational subsystems.

The demand to deliver cutting-edge technology faster than ever before at lower costs is certainly challenging. Yet, by leveraging open standards and proven technologies in a modular, building block approach, meeting today’s needs with designs that allow for cost-effective, rapid future expansion is a realistic and achievable goal. This approach will ensure that platforms are versatile and adaptable enough to manage diverse ground, sea, and air-based payloads while meeting continuously changing mission goals.

This article was written by Darryl McKenney, Vice President, Engineering Services, and Dan Coolidge, Sr. Mechanical Engineer, Mercury Systems, Inc. (Chelmsford, MA). For more information, visit http://info.hotims.com/45608-400.