A.6.1:5.3 - Manufacturing: fixture selection
A machining team declares a fixture-selection mechanism. Its operations filter candidate fixtures, compare admissible loading envelopes, and return a non-dominated candidate set. Laws preserve units and the partial order over constraints. The admission predicate evaluates true only when current workpiece geometry, machine envelope, and measurement qualification interval are available.
The machinist’s setup method and the dated setup work remain separate. A fixture is a system. A selector implementation may realize the mechanism for a stated scope and interval.
Positive realization in plain terms. FixtureSelectorRuntime-12-E3 realizes exact mechanism episteme FixtureSelectionMechanism-E3 for Cell7FixtureSelection-Q3 during [2026-07-01T08:00Z, 2026-07-19T14:32Z). During that interval the independently identified runtime provided filterCandidates, compareLoadingEnvelopes, and returnNonDominatedSet; every admitted use required current workpiece geometry, the current machine envelope, and a current measurement-qualification interval; and its results preserved the declared unit and constraint-partial-order laws.
| Realization position or test | Filled value |
|---|---|
| declared mechanism | FixtureSelectionMechanism-E3 : U.Mechanism, the exact mechanism episteme containing those operations, laws, admission conditions, and Applicability |
| realizing entity | FixtureSelectorRuntime-12-E3 : U.System; the runtime keeps its system kind |
| realization scope | Cell7FixtureSelection-Q3 : U.ClaimScope, covering fixture selection for machining cell 7 under the named machine-envelope and qualification conditions |
| realization predicate | the runtime provides all three declared operations, enforces GeometryCurrent, MachineEnvelopeCurrent, and MeasurementQualificationCurrent before an application is admitted, and preserves UnitPreservationLaw and ConstraintPartialOrderLaw in returned candidate sets |
| derived extent | the maximal continuous interval [2026-07-01T08:00Z, 2026-07-19T14:32Z) over which those facts obtain |
If a later claim needs this positive realization occurrence, its identity is <FixtureSelectionMechanism-E3, FixtureSelectorRuntime-12-E3, Cell7FixtureSelection-Q3, [2026-07-01T08:00Z, 2026-07-19T14:32Z)>. The interval is derived, not a fourth writable participant.
Runtime contrast. FixtureSelectorRuntime-12-FastPath-E4 : U.System exposes the same three operation names but accepts a loading-envelope comparison when MeasurementQualificationCurrent is false. It therefore bypasses one declared admission condition and does not realize FixtureSelectionMechanism-E3 for that scope, even if its returned candidate set happens to match E3 in one run. A missing audit-log segment for E3 instead reopens evidence and warrant under A.10. Without demonstrated cessation or bypass, that gap does not make the world-side realization predicate false or split its occurrence, although the project may have to withhold its positive assertion until warrant recovers. Demonstrated cessation followed by later restored conformity would create a later maximal-continuous realization occurrence.
Practical payoff: the team can replace the implementation without turning a scalar convenience score into the declared ordering law, and it can reject a look-alike implementation without rewriting the declaration.