Hybrid Models, Hidden Extrapolation, and Mechanical Safety

Abstract

Reliable deployment in high- and low-cycle fatigue prediction depends on more than obtaining a strong benchmark result. This conceptual analysis uses extrapolation control to study how claims travel from data to model output and then to action. Its central thesis is that the unit of assurance must be the digital thread connecting geometry, materials, boundary conditions, solver settings, derived features, and predicted capacity. The reviewed evidence shows recurring risks from hidden distribution change, correlated evaluation error, missing provenance, and optimization objectives that omit downstream costs. In response, the article proposes a layered evaluation program combining controlled perturbations, subgroup and scenario analysis, repeated runs, calibration or selective prediction, and monitoring after release. It also asks who can inspect, override, and learn from failures. By integrating the assigned target papers with established scholarship, the synthesis clarifies which findings transfer across domains and which remain local to a benchmark, dataset, or experimental apparatus. The goal is a testable research program for bounded, traceable, and revisable systems.