Program Manager: Dr. Leo Christodoulou
 The major limitation in the readiness of combat systems/platforms is the lengthy inspections with the resultant conservative "go, no-go" operation decisions made to avoid the failure of materials in critical components. The goal of the Prognosis Program is to manage this “fear of failure” through the determination of remaining usable life and the quantitative prediction (Prognosis) of future operating capability. As a result, commanders will have the ability to adaptively manage, deploy, and use combat systems/platforms that otherwise would have been removed from service.
Both power-train (gas turbine engine and gearbox) and airframe subsystems were chosen as the “testbeds” for this program because they are responsible for frequent inspections and downtime in defense platforms (air, land, sea, manned, or unmanned). Using these testbeds, the program will develop novel methods for interrogating materials (local and global) that capture the intrinsic behavior of the materials. This “self knowledge of state” will then be fed into program-developed, physics-based, multi-scale models that describe the failure and damage accumulation in materials and their cascading effect on future performance.
The staggeringly complicated problem of prediction is made tractable by applying physics-based approaches to the nucleation and growth of failure-causing defects, tracking the evolution in the microstructure through models and suitable interrogation tools, and constraining the predictions to the short term (imminent deployment). This constraint implies that only changes in system capability and signature need to be predicted and tracked and is compatible with the aim of supporting asset management, deployment, and use of combat systems under “expeditionary force” and unmanned platform scenarios. (Note: the system may be recalibrated at a more convenient time and location.) Treating the microstructure as the evolving state variable on which future behavior depends eliminates the need to test every conceivable damage scenario for every system.
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