In 2015, the US Department of Defense announced that the B-52 bomber, originally introduced in 1952, will be in operation until 2044 – a life cycle of nearly 100 years.
One of the largest operational costs associated with automated test systems, especially in the aerospace and defense industry, is the support and maintenance cost over the life of the system. Proactive life-cycle management requires designing maintainable testers, diligently monitoring automated test equipment (ATE), and tracking instrument and component end-of-life (EOL) notifications.
While life-cycle management might not be a novel concept, the reality is that the evolution of mobile technology, accelerated hardware obsolescence, and sheer volume of test software are making this task increasingly difficult. Best-in-class organizations are rearchitecting test strategies to gain a competitive advantage amid the growing challenge of life- cycle management.
Evolution of OS Life Cycles
Within a decade, OS providers have transitioned from releasing a single OS and maintaining it for several years, such as Microsoft Windows XP (which was supported for 13 years), to today’s paradigm that targets mobile users that expect constant upgrades. This requires OS providers to frantically release new versions and retroactively fix bugs in daily updates. Global market intelligence firm IDC forecasts that smartphones and tablets will control 88.4 percent of the smart-connected device market by 2019, leaving portable and desktop PCs with only 11.6 percent.
As mobile devices control vast majority of the market, OS providers will continue to prioritize the mobile user. This shift poses a monumental hurdle for test systems that rely on a stable OS to eliminate the need for system revalidation. As a result, some organizations are moving to Linux-based systems to have more control over the OS. Another approach is to minimize the number of OSs to reduce the burden for test engineering and
IT organizations. Many legacy test systems contain several OSs (one for each unique box instrument), which introduces the risk of revalidation due to individual OS updates. One major benefit of modular platforms, such as VXI or PXI, is the single OS controlling all instruments in the chassis or system.
Accelerated Decay of VXI and Legacy Instruments
In the late 1980s and early 1990s, the aerospace and defense community standardized on VXI as the modular commercial off-the-shelf platform for ATE systems. However, as VXI grows obsolete and support diminishes for legacy instruments, programs are under increased pressure to migrate to a stable alternative.
This is compounded by a looming RoHS conversion deadline, which will increase the rate of component and instrument EOLs.
Over the past decade, PXI has replaced VXI as the de facto modular platform for ATE systems due to the size, performance, cost, and level of innovation in the platform. Global consulting firm Frost & Sullivan expects PXI to grow by 17.6 percent annually, which accounts for most of the expected growth for the test and measurement industry. With nearly 70 vendors offering more than 1,500 PXI instruments and a steady stream of innovation, PXI will continue to provide increased value to long-life-cycle ATE systems.
TPS-Compatible Migration Paths
As teams migrate from VXI-based to PXI-based test systems, the investment required to modernize hardware will typically pale in comparison to that of updating and revalidating software. Due to the criticality of the system and the tight regulations for requirements tracking and software validation, simply opening, saving, and revalidating a test program set (TPS), or test sequence, can cost hundreds of thousands of dollars. This has created an environment where companies must rethink their software strategies or risk hemorrhaging money to sustain legacy testers.
“The cost to rewrite a TPS due to the replacement of legacy/obsolete instrumentation in a test system is approximately $150k/TPS. When multiplied across dozens of TPS per test system and three to five generations of test equipment over the life of a test system, the potential savings in TPS costs alone are very significant – any efforts that vendors can make to smooth this transition will prove to be invaluable.”
– David R. Carey, PhD, Associate Professor of Electrical Engineering, Wilkes University
Since minor software changes can greatly impact TPS compatibility, instrument vendors should offer offer TPS-compatible hardware migration options. This includes preserving driver functionality, APIs, and dependencies between driver versions to minimize the impact on the hardware abstraction layer. For example, NI is collaborating with Astronics Corporation to bring remaining VXI instruments into the PXI platform, such as the Astronics PXIe-2461 frequency time interval counter, which preserves TPS compatibility with legacy systems. Despite their best efforts, vendors cannot always provide TPS-compatible alternatives. In these situations, a common approach is emulating legacy instrument functionality. Recently, engineers have adopted software-designed instruments with user- programmable FPGAs to augment standard instrument capabilities with custom functionality to emulate legacy behavior. For example, filters and triggers that were common in instruments 20 years ago and obsolete in today’s instruments can be reengineered.
Coming Full Circle
Whether you’re managing the B-52 bomber platform or introducing a new line of infotainment systems for the connected car, life-cycle management is critical. It can be either an expensive afterthought or a competitive advantage. In the face of market dominance of mobile technologies, the accelerated decay of legacy instrumentation, and the rising costs of software validation, scalable test architectures and strategies will distinguish best-in-class organizations.
