{ "message": "9/9 medium-mesh oblique checks; 4 fine-mesh checks; 4 additional friction checks. The largest coarse-to-medium change among the three response metrics is 53.2%. These responses are mesh-sensitive; a numerically passing case is not proof of convergence. The coarse ranking is provisional and no winning helmet is established. Detailed paired comparisons are retained in refinement_summary.json.", "selection": { "candidate": "sphere_BAL_B", "selection": "Best eligible alternative under predeclared minimax score; may still be worse than baseline", "fine_mesh": [ 40, 12, 4 ], "critical_impacts": [ "oblique", "side" ], "friction_assumed_values": [ 0.0, 0.2, 0.4 ] }, "medium": [ { "id": "ref32_oval_BAL_AC_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -8.442369555791363, "peak_head_angular_accel_rad_s2": -43.05648992310854, "peak_head_angular_speed_rad_s": -31.85365933614697 } }, { "id": "ref32_oval_BAL_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -12.120220815457083, "peak_head_angular_accel_rad_s2": -52.88865591105301, "peak_head_angular_speed_rad_s": -26.38478549089961 } }, { "id": "ref32_oval_QI_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -13.726335624733876, "peak_head_angular_accel_rad_s2": -53.15932349356797, "peak_head_angular_speed_rad_s": -25.760915113708293 } }, { "id": "ref32_sphere_BAL_AC_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -12.424232945859115, "peak_head_angular_accel_rad_s2": 22.506671921097254, "peak_head_angular_speed_rad_s": 29.38107228549054 } }, { "id": "ref32_sphere_BAL_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -16.239966896611215, "peak_head_angular_accel_rad_s2": 22.42299776038459, "peak_head_angular_speed_rad_s": 25.664489844551763 } }, { "id": "ref32_sphere_QI_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": -17.329805440634626, "peak_head_angular_accel_rad_s2": 22.27024205155974, "peak_head_angular_speed_rad_s": 25.869505729474305 } }, { "id": "ref32_zoned_BAL_AC_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": 8.278335478069977, "peak_head_angular_accel_rad_s2": -31.411190961157388, "peak_head_angular_speed_rad_s": -30.973194061670306 } }, { "id": "ref32_zoned_BAL_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": 13.601460876760862, "peak_head_angular_accel_rad_s2": -37.999738497722035, "peak_head_angular_speed_rad_s": -30.898393044037288 } }, { "id": "ref32_zoned_QI_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_pct": { "peak_head_reference_accel_m_s2": 9.916413328142726, "peak_head_angular_accel_rad_s2": -35.7236078603436, "peak_head_angular_speed_rad_s": -30.180278674995954 } } ], "fine": [ { "id": "check40_mu20_oval_QI_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_coarse_pct": { "peak_head_reference_accel_m_s2": -23.85042446683565, "peak_head_angular_accel_rad_s2": -33.63035617772787, "peak_head_angular_speed_rad_s": -13.381029665758648 }, "values": { "peak_head_reference_accel_m_s2": 3215.847118484159, "peak_head_angular_accel_rad_s2": 11360.297186198864, "peak_head_angular_speed_rad_s": 14.151169245280848 } }, { "id": "check40_mu20_oval_QI_B_side", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_coarse_pct": { "peak_head_reference_accel_m_s2": -12.779398369674166, "peak_head_angular_accel_rad_s2": 20.99006366719283, "peak_head_angular_speed_rad_s": -11.237582324651507 }, "values": { "peak_head_reference_accel_m_s2": 2652.9075827215624, "peak_head_angular_accel_rad_s2": 6216.19457475686, "peak_head_angular_speed_rad_s": 10.764500720210613 } }, { "id": "check40_mu20_sphere_BAL_B_oblique", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_coarse_pct": { "peak_head_reference_accel_m_s2": -2.3131302541512078, "peak_head_angular_accel_rad_s2": 27.676005444220575, "peak_head_angular_speed_rad_s": 9.09466283635032 }, "values": { "peak_head_reference_accel_m_s2": 3811.1203495303394, "peak_head_angular_accel_rad_s2": 11024.37414751812, "peak_head_angular_speed_rad_s": 13.318384227367767 } }, { "id": "check40_mu20_sphere_BAL_B_side", "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_coarse_pct": { "peak_head_reference_accel_m_s2": 3.7092721789386607, "peak_head_angular_accel_rad_s2": -2.2969812224357122, "peak_head_angular_speed_rad_s": -22.095149829875073 }, "values": { "peak_head_reference_accel_m_s2": 3290.483420543584, "peak_head_angular_accel_rad_s2": 10944.443905304777, "peak_head_angular_speed_rad_s": 12.393560192439272 } } ], "friction": [ { "id": "check24_mu00_oval_QI_B_oblique", "mu": 0.0, "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_mu02_pct": { "peak_head_reference_accel_m_s2": -3.4472428647632114, "peak_head_angular_accel_rad_s2": -2.47244685209399, "peak_head_angular_speed_rad_s": 37.539518152067416 } }, { "id": "check24_mu00_sphere_BAL_B_oblique", "mu": 0.0, "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_mu02_pct": { "peak_head_reference_accel_m_s2": -4.788238253611321, "peak_head_angular_accel_rad_s2": 6.124565442839769, "peak_head_angular_speed_rad_s": 33.98741462806465 } }, { "id": "check24_mu40_oval_QI_B_oblique", "mu": 0.4, "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_mu02_pct": { "peak_head_reference_accel_m_s2": 6.866788592466433, "peak_head_angular_accel_rad_s2": 45.67870459800778, "peak_head_angular_speed_rad_s": 61.59175204704237 } }, { "id": "check24_mu40_sphere_BAL_B_oblique", "mu": 0.4, "status": "PASS_NUMERICAL_SCREEN_ONLY", "changes_from_mu02_pct": { "peak_head_reference_accel_m_s2": 8.566526740272739, "peak_head_angular_accel_rad_s2": 192.17884755637522, "peak_head_angular_speed_rad_s": 97.97511516672573 } } ], "paired_comparisons": [ { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "crown", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -16.91203992170435, "peak_head_angular_accel_rad_s2": -1.7269026068982285, "peak_head_angular_speed_rad_s": 41.60824943069743 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "front", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -14.564458119987478, "peak_head_angular_accel_rad_s2": 23.56414223737786, "peak_head_angular_speed_rad_s": 14.95013320235612 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "side", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": 4.313154130630759, "peak_head_angular_accel_rad_s2": 118.02727279064374, "peak_head_angular_speed_rad_s": 31.179754994404462 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "rear", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -2.1587687931550747, "peak_head_angular_accel_rad_s2": 16.584251254997806, "peak_head_angular_speed_rad_s": 3.7542201414705767 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "oblique", "mu": 0.0, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -8.90081662183696, "peak_head_angular_accel_rad_s2": -45.107495244807325, "peak_head_angular_speed_rad_s": -27.204382240813697 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "oblique", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -7.617744209382849, "peak_head_angular_accel_rad_s2": -49.55426528632311, "peak_head_angular_speed_rad_s": -25.274517625602254 } }, { "candidate": "sphere_BAL_B", "nt": 24, "nv": 8, "impact": "oblique", "mu": 0.4, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -6.148385520721156, "peak_head_angular_accel_rad_s2": 1.1759177393063647, "peak_head_angular_speed_rad_s": -8.449622016266156 } }, { "candidate": "sphere_BAL_B", "nt": 32, "nv": 10, "impact": "oblique", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": -10.30935269504768, "peak_head_angular_accel_rad_s2": 31.84519371801533, "peak_head_angular_speed_rad_s": 26.48781481276945 } }, { "candidate": "sphere_BAL_B", "nt": 40, "nv": 12, "impact": "side", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": 24.033096440093328, "peak_head_angular_accel_rad_s2": 76.06340621557617, "peak_head_angular_speed_rad_s": 15.133627787957327 } }, { "candidate": "sphere_BAL_B", "nt": 40, "nv": 12, "impact": "oblique", "mu": 0.2, "eligible": true, "candidate_change_pct": { "peak_head_reference_accel_m_s2": 18.51061972519301, "peak_head_angular_accel_rad_s2": -2.9569916453316303, "peak_head_angular_speed_rad_s": -5.884920203260224 } } ], "interpretation": "Deterministic sensitivity checks, not statistical confidence intervals. No asymptotic convergence demonstrated." }