In recent years, military and aerospace programs have dedicated significant resources toward research in advanced predictive maintenance technologies. In particular, much of the research focused on prognostics—developing sensors and measurements that they hope will not only improve system readiness, but also reduce the costs of product sustainment. Designed to identify incipient failures at the lowest levels of the system architecture, prognostic sensors are typically the end result of extremely detailed, yet extremely localized, physics-of-failure ("PoF") analyses.
Since DSI is the original pioneer of the need for Testability as an integral component of the design development process for the US Department of Defense, and has mentored William Keiner, author of the first Testability Standard (MIL-STD 2165) prior to its acceptance in 1981, we have continued to lead industry in this purpose.
As the eXpress models are integrated into the system, the design must be able to detect the failures within the context of an integrated diagnostic model, which is a woeful inadequacy of most every other testability analysis. As the models are integrated more “test” constraints become apparent due to the integrated system posing new testing accessibility restrictions. This alone, may significantly degrade the usability of test points that were previously accessible when the design is independent from the other integrated designs.