Engineering Systems: Admissibility, Identity, and Structural Persistence

This paper extends the Paton System into the domain of engineering systems, treating engineered artefacts as constraint-realisation structures operating within bounded admissibility corridors. Building upon constraint primacy, the Boundary–Relation–Persistence (BRP) framework, and the Lowest Admissible Configuration (LCD) under strain principle, the work formalises engineering identity, design admissibility, structural compression, and failure conditions. Engineering systems are modelled as load-bearing state machines whose persistence depends on preserving an invariant Engineering Identity Datum within a constrained configuration space. Under increasing structural strain, degrees of freedom compress toward a minimal viable configuration; if that configuration becomes inadmissible, failure or structural reconfiguration follows. The framework is descriptive rather than prescriptive and introduces no new ontology, applying the same constraint-first operator used across physical, economic, institutional, and AI domains.