{"abstention_reason":null,"arm":"SUBSTRATE_DIVERSE_P2","candidate_id":"agency_structure_attribution_balance__engineering_design__SUBSTRATE_DIVERSE_P2","cell_id":"agency_structure_attribution_balance__engineering_design","decision":"PROPOSAL","experiment_id":"eoa_inverse_innovation_exp13_second_slot_policy60_20260806","proposal":{"actors":["Assembly technician whose identity is focal in the preload-variation report","Other qualified assembly technicians used in crossover trials","Bolted-joint design engineer","Manufacturing and tooling engineer","Metrology engineer","Torque-tool calibration technician","Fastener and lubricant suppliers","Quality and ergonomics engineers","Production supervisor","Design authority responsible for joint acceptance"],"affected_objective":"Reduce out-of-tolerance clamp load in manually assembled bolted joints while distinguishing technician-specific technique from torque-tool, fixture, access-geometry, fastener-lot, lubricant, and joint-compliance effects.","arm":"SUBSTRATE_DIVERSE_P2","authority_safety":{"authorized_first_step":"The metrology engineer may conduct a low-energy bench trial using surrogate fasteners, an unloaded replica fixture, existing calibrated tools, and three consenting qualified technicians; production hardware and acceptance records remain untouched.","decision_authority":"The bolted-joint design authority retains authority over specifications and acceptance; manufacturing engineering controls tooling changes, and authorized quality and personnel processes retain authority over production release or individual performance decisions.","excluded_actions":["Testing flight, pressure-boundary, energized, implanted, or otherwise safety-critical production hardware","Changing released torque, preload, lubricant, fastener, fixture, or acceptance specifications","Using the rig result alone for discipline, qualification removal, blame, liability, or compensation","Exceeding the load-cell, surrogate-fastener, fixture, or tool ratings","Representing variance attribution as proof of intention, negligence, or general competence","Using uncalibrated instrumentation or combining results across materially different joint geometries"],"halt_rollback":"Stop if calibration checks fail, fixture movement or fastener yielding occurs, any rating is approached, a participant reports unsafe loading or coercion, or production disposition begins relying on unreviewed results. Unload the rig, quarantine the run, retain raw witness records under metrology control, and revert to the existing acceptance process."},"baseline":"The line audits torque-wrench settings and final indicated torque. When one technician's joints show excess preload scatter, the technician is retrained or reassigned. This baseline does not directly measure clamp load and cannot separate technique from friction, fixture compliance, access angle, tool dynamics, or material-lot variation.","candidate_id":"agency_structure_attribution_balance__engineering_design__SUBSTRATE_DIVERSE_P2","causal_chain":["Final torque collapses thread friction, under-head friction, joint compliance, access geometry, tool response, and technician motion into one reading, allowing the most visible technician to absorb causal credit or blame for clamp-load scatter.","A surrogate fastener with an axial load cell directly measures achieved clamp load while a mechanically instrumented wrench records applied torque and rotation.","Interchangeable fixture inserts reproduce the relevant joint compliance and access geometry, while controlled fastener and lubricant lots expose material-condition effects.","Technicians cross over among the same physical tool, fixture, and material combinations, revealing whether preload patterns follow a person, a physical condition, or their interaction.","A hand-cranked constant-rate mechanical drive repeats selected combinations without human technique, providing a bounded physical actor-substitution probe.","Matched fixture inserts then relax one structural condition at a time, such as compliance or wrench approach angle, while the technician and material lot remain fixed.","Repeated physical measurements classify initiating, amplifying, constraining, and executing roles without converting them into moral or personnel judgments.","The design authority can target a supported physical mechanism—tool repair, fixture stiffening, access redesign, friction control, or joint redesign—while retaining an actor-specific technique hypothesis when it alone survives the swaps."],"cell_id":"agency_structure_attribution_balance__engineering_design","consequence":"Misattributing preload scatter to a technician can prompt ineffective retraining while defective tooling, inaccessible geometry, unstable friction, or excessive fixture compliance continues producing loose, overstressed, or fatigue-prone joints. Treating the station as wholly determinative can conversely conceal a repeatable technique-dependent loading pattern.","diversity_from_prior_proposals":"Unlike P1's read-only documentary annex for attribution after a composite pressure-vessel rupture, this opportunity concerns non-destructive bench diagnosis of clamp-load scatter in manual bolted-joint assembly. It introduces a physical crossover measurement rig, controlled mechanical substitutions, and a metrology-to-hardware-correction path; it neither repairs nor extends P1's failure-review intervention.","experiment_id":"eoa_inverse_innovation_exp13_second_slot_policy60_20260806","intervention":"Build a benchtop physical crossover rig around a rated surrogate bolted joint. The rig combines an axial load-cell fastener, torque-and-angle instrumentation, interchangeable compliance and access-geometry inserts, controlled fastener/lubricant lots, and a hand-cranked constant-rate mechanical wrench drive. Qualified technicians assemble matched surrogate joints across swapped physical conditions; the mechanical drive repeats selected cells as an actor-substitution condition. Direct clamp-load traces show whether variation follows the technician, tool, geometry, material condition, or a specific interaction. Digital logging may assist, but calibrated analog indicators, mechanical swaps, and physical witness traces are sufficient for the essential comparison.","mechanism_mapping":[{"counterfactual_removal":"Without direct clamp-load and torque-angle measurement, identical final-torque readings remain unable to distinguish frictional loss, elastic loading, and technician motion.","mechanism_slug":"actor_structure_evidence_matrix","role":"Populates each technician-by-tool-by-fixture-by-material cell with directly measured preload, torque, rotation, calibration state, and timing."},{"counterfactual_removal":"Without physical crossover, a stable association between one technician and one workstation remains confounded and cannot identify whether the pattern follows the actor or the structure.","mechanism_slug":"comparative_case_attribution_test","role":"Compares the same technicians under different physical conditions and the same conditions with different technicians."},{"counterfactual_removal":"Without the mechanical drive, observed differences among people cannot be bounded against a repeatable nonhuman input applied through the same tool and joint.","mechanism_slug":"counterfactual_actor_substitution_probe","role":"Substitutes a constant-rate mechanical input for technician motion while preserving the measured tool, fixture, fastener, lubricant, and joint."},{"counterfactual_removal":"Without interchangeable inserts and controlled lots, fixture, access, compliance, and friction conditions can only be named as context rather than physically varied and tested.","mechanism_slug":"structural_constraint_relaxation_probe","role":"Changes one material or geometric constraint at a time while holding the focal technician and remaining conditions fixed."},{"counterfactual_removal":"Without tracing torque and rotation into measured axial force, the study can report correlations but cannot show how human input and physical conditions combine to create preload scatter.","mechanism_slug":"process_tracing_across_levels","role":"Traces hand or drive input through wrench mechanics, interface friction, fastener elongation, joint compression, and achieved clamp load."}],"nearest_rivals":["A torque-wrench calibration check, which can identify tool bias but does not test technician, fixture, material, and interaction effects","Final-torque auditing, which verifies an input proxy rather than directly measuring achieved clamp load","Ultrasonic bolt-elongation inspection, which measures preload in a completed joint but does not by itself provide controlled actor and structural substitutions","Operator retraining or qualification testing, which evaluates repeatability but can preserve confounding with the assigned station and material lot","A designed experiment using ordinary production measurements, which may estimate factor effects but lacks the rig's direct axial-force measurement and mechanical actor substitute"],"negative_tests":{"intervention_falsifier":"The rig is falsified as a useful attribution intervention if calibration-confirmed repeats show that its measured preload uncertainty is large enough to obscure the production-relevant scatter, crossover patterns are not reproducible, or its surrogate geometry cannot preserve the torque–rotation–clamp-load relationships of the target joint.","problem_falsifier":"The attribution problem is absent if existing traceable measurements already directly show clamp load, cross technicians among calibrated tools and fixtures, control fastener and lubricant lots, vary physical geometry and compliance, and distinguish person, position, structural, and interaction effects without using technician identity or final torque as a causal proxy.","risks":["The surrogate joint may not reproduce production friction, compliance, or access constraints.","Load-cell or torque-angle calibration error may fabricate apparent actor or fixture effects.","Technician fatigue, learning, or order effects may be mistaken for stable agency.","The mechanical drive may remove more than technique, limiting the substitution claim.","Fastener reuse, temperature, lubricant migration, or seating history may contaminate comparisons.","Personnel processes may misuse an exploratory physical pattern as proof of fault.","Fixture overload, pinch points, tool kickback, or fastener fracture could injure participants if ratings and guarding are inadequate."],"strongest_counterevidence":"If calibrated direct-preload records from production already show that the excess scatter follows the same technician across multiple tools, fixtures, access geometries, controlled material lots, and randomized repetitions, while other technicians remain stable in every one of those conditions, the structural-confounding diagnosis would be substantially weakened."},"next_evidence_step":"On one unloaded replica joint, verify the load-cell fastener against a traceable compression standard and establish repeatability with the mechanical drive. Then run a guarded, randomized pilot comprising three technicians, two calibrated wrenches, two fixture inserts, and two controlled fastener/lubricant lots, with fresh surrogate fasteners where required. Compare whether preload variance follows technician, physical condition, or interaction; stop after the pilot and obtain design-authority review before proposing any production change.","observable_state":"Nominally identical manual assemblies reach the specified final torque but exhibit materially different measured or inferred clamp loads. The outliers are concentrated in work signed by one technician, yet that technician has primarily used one wrench, one constrained approach angle, one fixture, and several fastener or lubricant lots. Tool calibration status, torque-angle shape, fixture deflection, friction condition, and direct axial preload have not been observed together under crossed physical conditions.","prior_art_status":"UNSEARCHED","problem":"A bolted-joint assembly line attributes excessive clamp-load scatter to one technician because that person's signed work contains most outliers, while others attribute the scatter generically to the workstation. Technician assignment is confounded with wrench, fixture, access geometry, fastener lot, lubricant condition, and joint compliance, and final torque is only an indirect proxy for clamp load. The organization therefore cannot tell whether the pattern arises from technician technique, physical structure, or their interaction.","proposal_index":2,"remaining_contrastive_claim":"A rated physical crossover rig that directly measures axial clamp load and includes both technician swaps and a mechanical input substitute can distinguish person-following, hardware-following, material-following, and interaction-specific preload patterns that torque auditing, calibration alone, or retraining cannot distinguish.","revision_record":{"claim_changes":["Initial closed-book hypothesis; no novelty, prevalence, or effect-size claim is made.","The contrastive claim is limited to discriminating physical sources of clamp-load scatter on a representative surrogate joint."],"conceptual_changes":["Creates an independent P2 mapping actor–structure attribution to manual assembly metrology rather than post-failure historical review.","Embodies actor substitution and structural relaxation as controlled physical swaps rather than documentary counterfactuals."],"evidence_changes":["No external evidence or prior-art search was consulted.","Proposed evidence consists of traceable force, torque, rotation, fixture, lot, and calibration observations from a bounded bench pilot."],"operational_changes":["Initial use is restricted to unloaded surrogate hardware and cannot change production disposition or personnel status.","Digital analysis and logging are explicitly nonessential to the intervention's causal effect."],"parent_version":null,"progress_targets_addressed":["Material independence from sealed P1","Measurement/instrumentation as the primary causal substrate","Concrete physical state and actors","Direct actor and structural substitution tests","Removal-based mechanism tests","Authority limits, safety controls, falsifiers, risks, and bounded evidence step"]},"schema_version":1,"structural_mapping":[{"archetype_element":"Explanatory Target, Scope, and Use","domain_realization":"Achieved clamp-load scatter on one defined surrogate joint, over a bounded assembly cycle, used only to identify candidate physical corrective mechanisms."},{"archetype_element":"Focal Actor and Collective Inventory","domain_realization":"The outlier-associated technician remains visible alongside other technicians, joint designers, tooling, metrology, calibration, suppliers, quality, and the design authority."},{"archetype_element":"Structural Condition and Path Map","domain_realization":"The rig represents wrench mechanics, access angle, fixture stiffness, thread and bearing friction, fastener lot, lubricant state, joint compliance, and load-path geometry."},{"archetype_element":"Agency Contribution Trace and Causal Role Classification","domain_realization":"Measured torque, rotation, and axial force connect technician input to initiating, modulating, seating, detecting, or executing roles rather than inferring causality from a signature."},{"archetype_element":"Opportunity, Constraint, and Selection Map","domain_realization":"Crossover assignments separate technician technique from the physical station and material conditions that shaped the available motion and force transfer."},{"archetype_element":"Counterfactual Actor Substitution Test","domain_realization":"A rated constant-rate mechanical drive supplies a repeatable substitute input through the same wrench and joint conditions."},{"archetype_element":"Structural Counterfactual and Constraint Test","domain_realization":"Interchangeable inserts and controlled material lots physically vary compliance, access geometry, and friction while other conditions remain fixed."},{"archetype_element":"Cross-Scale Actor–Structure Interaction Map","domain_realization":"The measurement chain connects hand motion, tool response, interface friction, fastener elongation, fixture deformation, and joint clamp load."},{"archetype_element":"Attribution Uncertainty, Responsibility Boundary, and Review Rule","domain_realization":"Calibration uncertainty, order effects, surrogate fidelity, and interactions remain explicit; no measured contribution determines blame, qualification, or design authority."}],"substrate_contract":{"counterfactual_independence":"Removing software, databases, automated analysis, digital control, training changes, or workflow rules leaves the essential effect intact: calibrated physical sensors measure force, torque, and rotation while mechanical swaps and the hand-cranked drive produce the discriminating comparisons. Removing the load path, instrumentation, interchangeable inserts, or mechanical substitute destroys that effect.","forbidden_channel_audit":"Governance supplies authorization and safety boundaries only; trial scheduling supplies exposure to conditions only; statistics or software may summarize observations only. No incentive, training program, information-routing system, algorithm, model, database, or digital controller generates the preload differences or the essential evidence. The causal substrate is the mechanically loaded surrogate joint and its measurement instrumentation.","primary_allowed_process":"MEASUREMENT_INSTRUMENTATION"},"title":"Physical Crossover Rig for Human–Fixture Attribution in Bolted-Joint Preload Scatter","version":0},"schema_version":1}