{"schema_version":1,"experiment_id":"eoa_inverse_innovation_exp09_archetype_breadth150_20260804","cell_id":"feedback_loop_redirection__chemistry_materials","arm":"BREADTH_PROBE_ONE_SHOT","candidate_id":"feedback_loop_redirection__chemistry_materials__P1","proposal_index":1,"version":0,"title":"Exotherm-Aware Cure-Loop Retargeting for Thick Thermoset Composites","problem":"During the programmed cure of a thick thermoset composite, a heater controller tracks a tool-surface thermocouple that can remain below its setpoint while the reacting core is already heating through its own cure exotherm. The controller responds to the apparent surface-temperature deficit by supplying more heat; the added heat accelerates core cure and heat generation, widening the unobserved core-to-surface divergence and eliciting still more controller heating.","actors":["Composite process engineer who owns the cure recipe and control limits","Cure-oven or heated-tool controller that adjusts heater power","Operator responsible for the instrumented cure and emergency shutdown","Materials or quality engineer evaluating cure uniformity and damage"],"observable_state":"The surface thermocouple reports a temperature below the programmed ramp or hold target while an embedded core thermocouple reports a rising core-to-surface temperature difference and a dielectric cure sensor reports accelerating conversion or cure rate. Heater duty remains elevated because the existing controller responds only to the surface error.","consequence":"The core can exceed its approved thermal envelope or cure substantially ahead of outer regions, creating a risk of resin degradation, residual-stress gradients, undercured outer material, or rejection of the composite part.","affected_objective":"Complete cure throughout the composite while keeping internal temperature and spatial cure-state differences inside an approved process envelope.","intervention":"Replace surface-temperature-only control with an auditable, bounded control rule targeting both cure advancement and thermal uniformity. Retain the surface thermocouple, add an embedded core temperature and a dielectric cure-rate signal, and compute core-to-surface temperature difference. During an exotherm-sensitive window, reduce heating gain or enter a no-additional-heat hold when core temperature, core-to-surface difference, or cure-rate rise crosses engineer-set thresholds; resume the programmed ramp only after all signals return to the approved envelope. Keep independent hard temperature trips and allow immediate reversion to the validated baseline recipe.","structural_mapping":[{"archetype_element":"Existing feedback loop","domain_realization":"Surface temperature error determines heater power, which changes resin temperature and cure rate, which changes generated heat and future measured temperature."},{"archetype_element":"Undesirable reinforcement path","domain_realization":"A cool-looking surface triggers additional heating even as the core exotherm accelerates, so controller action can reinforce internal overheating."},{"archetype_element":"Signal modification","domain_realization":"The controller receives core temperature, core-to-surface temperature difference, and dielectric cure-rate information in addition to surface temperature."},{"archetype_element":"Target redefinition","domain_realization":"The controlled target changes from surface ramp tracking alone to cure progression within an internal-temperature and uniformity envelope."},{"archetype_element":"Response-rule and gain change","domain_realization":"Rising internal exotherm causes heater gain reduction or a bounded hold instead of continued heating to eliminate surface error."},{"archetype_element":"Monitoring and adjustment","domain_realization":"Logged signals, commands, threshold crossings, cure uniformity, and sensor disagreements are reviewed after each authorized test, with thresholds adjustable only by the process owner."}],"mechanism_mapping":[{"mechanism_slug":"signal_modification","role":"Expose the internal thermochemical state that the surface-only controller cannot distinguish from an ordinary heating lag.","counterfactual_removal":"Without the core and cure-rate signals, the controller continues treating a surface deficit as permission to add heat regardless of internal exotherm."},{"mechanism_slug":"response_rule_change","role":"Translate evidence of accelerating internal cure into reduced heater duty or a hold rather than further ramp tracking.","counterfactual_removal":"If the new signals are displayed but do not alter heater response, the intervention is passive monitoring and the reinforcing path remains intact."},{"mechanism_slug":"gain_adjustment","role":"Lower controller sensitivity to surface-temperature error during the exotherm-sensitive window so corrective heating does not dominate the internal safety envelope.","counterfactual_removal":"An unchanged high gain could keep driving heat into the part until a hard trip, or could produce oscillatory heating when the new constraints activate."}],"causal_chain":["The surface sensor remains below its programmed target during a thick-part cure.","The baseline controller interprets the surface error as insufficient heating and raises heater duty.","Additional heat accelerates the core reaction and its heat generation.","Because the core state is not part of the response rule, internal temperature can diverge further before the surface catches up.","The revised loop observes core temperature, thermal gradient, and cure-rate acceleration.","Threshold crossings reduce heating gain or initiate a bounded hold.","Lower external heat input removes the controller's contribution to the reinforcing exotherm while cure continues under monitored limits.","Heating resumes only after the internal state returns to the approved envelope, redirecting control toward uniform, bounded cure rather than surface tracking alone."],"baseline":"A validated ramp-and-hold cure controlled by a surface thermocouple PID, with fixed gains and an independent high-temperature emergency trip but no internal cure-state input to routine heater commands.","nearest_rivals":["Use a uniformly slower fixed heating ramp without sensing internal cure state.","Lower catalyst loading or otherwise reformulate the resin to reduce exotherm.","Add passive heat spreading, insulation changes, or part-thickness restrictions.","Retain the existing controller and rely on a core-temperature emergency cutoff.","Model the cure offline and issue a new fixed recipe without closing the loop on each part."],"remaining_contrastive_claim":"Conditional on controller-supplied heat materially reinforcing the core exotherm, retargeting the existing feedback loop to internal cure progression and thermal-gradient limits addresses the signal-to-response error directly; fixed slower schedules and trip-only protection do not adapt routine heater commands to the observed internal state.","authority_safety":{"decision_authority":"The composite process owner may approve threshold logic and laboratory trials; the operator retains immediate stop authority, and production release remains with the existing materials and quality approval process.","authorized_first_step":"Run the proposed rule in non-actuating shadow mode during one instrumented sacrificial-coupon cure, recording the commands it would issue without allowing it to control heaters.","excluded_actions":["Autonomous control of production-part cures","Changing the validated resin formulation","Disabling independent temperature trips or interlocks","Exceeding approved equipment, material, or coupon temperature limits","Using an uncalibrated sensor as the sole basis for heater control"],"halt_rollback":"Stop the trial if any approved temperature limit is reached, sensors disagree beyond a preset tolerance, a sensor fails, or the operator observes abnormal behavior. Because the first test is shadow-only, rollback is immediate removal of the added instrumentation and continued use of the validated baseline controller."},"negative_tests":{"strongest_counterevidence":"Synchronized cure traces show that core temperature and cure-rate acceleration do not precede or diverge from the surface signal, and heater duty does not rise during the alleged exotherm reinforcement; observed defects instead track formulation, layup, or heat-removal variation.","problem_falsifier":"With heater power held constant or disabled during the relevant interval, the same internal thermal trajectory occurs, showing that the controller's surface-error response is not materially recreating or amplifying the undesirable state.","intervention_falsifier":"In shadow replay or a later authorized bounded actuation test, the revised rule fails to identify the divergence before the baseline trip, recommends heat reductions when independent cure measurements show no exotherm risk, or yields greater thermal gradients, oscillation, or incomplete cure than the baseline.","risks":["Embedded sensors may perturb the coupon or report a nonrepresentative local state.","The dielectric signal may drift with resin formulation, geometry, or sensor contact.","Conservative thresholds may produce undercure or unnecessarily long cycles.","Aggressive switching may create heater-command oscillation.","A failed core sensor could suppress needed heat unless plausibility checks and fallback rules are enforced.","Focusing on control logic could mask a formulation, tooling, or heat-removal defect that requires direct correction."]},"next_evidence_step":"On one laboratory-scale sacrificial coupon representative of the problematic thickness, collect synchronized surface temperature, embedded core temperature, dielectric cure signal, heater duty, and baseline controller output while the candidate controller runs in shadow mode. Predefine the exotherm window, signal-tolerance limits, and candidate thresholds; then determine whether the candidate consistently detects core divergence before the baseline controller or hard trip and whether its hypothetical commands remain bounded and non-oscillatory. This step tests loop identification and response logic but does not authorize actuation or an effect claim.","prior_art_status":"UNSEARCHED","diversity_from_prior_proposals":"No comparison with prior proposals was performed under runtime isolation; this candidate is derived solely from the supplied archetype and chemistry-and-materials domain card and instantiates a thermochemical process-control loop.","revision_record":{"parent_version":null,"progress_targets_addressed":[],"conceptual_changes":[],"operational_changes":[],"evidence_changes":[],"claim_changes":[]}}