{"abstract":"At the moment of sunrise the tracker stays flat instead of parking toward the sun.","category":"Solar tracker geometry","checks":7,"contract":"sun_el < 0: [0.0, 'night']. 0 <= sun_el < wake_el: park facing the low sun, [-east_lim, 'dawn'] in the morning (am true) or [west_lim, 'dusk'] in the evening. Otherwise track the ideal angle clamped to the asymmetric limits [-east_lim, west_lim] ('track'). Angles are floats.","contract_signature":"ideal, sun_el, am, wake_el, east_lim, west_lim","evaluation_group":"w2-solar_tracker_geometry-dawn-dusk-parking","failed_approach":"Extending night to -1 degree parks trackers while the sun is still below the horizon.","family":"w2-solar_tracker_geometry-dawn-dusk-parking-night-boundary","id":"FA-93801","implementations":{"attempt":{"sha256":"0e08ff0624f05d8a2a69951b96c9c3cf9ad3cf3b9101732e235d1614bffcf516","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(ideal, sun_el, am, wake_el, east_lim, west_lim):\n    if sun_el < -1:\n        return [0.0, 'night']\n    if sun_el < wake_el:\n        if am:\n            return [-float(east_lim), 'dawn']\n        return [float(west_lim), 'dusk']\n    return [float(max(-east_lim, min(west_lim, ideal))), 'track']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [70, 0, True, 3, 45, 50], [-45.0, 'dawn']],\n  ['regression: night boundary (partial repair)', [70, -1, True, 3, 45, 60], [0.0, 'night']],\n  ['control 1', [45, 5, False, 3, 45, 50], [45.0, 'track']],\n  ['control 2', [55, 3, True, 3, 50, 50], [50.0, 'track']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [70, 0, False, 3, 45, 60], [60.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-70, -1, False, 3, 50, 60], [0.0, 'night']],\n  ['control 1', [70, 5, False, 3, 50, 50], [50.0, 'track']],\n  ['control 2', [0, -6, True, 3, 50, 60], [0.0, 'night']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [45, 0, True, 5, 45, 60], [-45.0, 'dawn']],\n  ['regression: night boundary (partial repair)', [-20, -1, False, 3, 45, 50], [0.0, 'night']],\n  ['control 1', [0, 8, True, 5, 55, 50], [0.0, 'track']],\n  ['control 2', [-20, 0, False, 5, 55, 50], [50.0, 'dusk']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [-50, 0, False, 3, 55, 50], [50.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-20, -1, False, 3, 55, 50], [0.0, 'night']],\n  ['control 1', [-20, 3, False, 3, 45, 50], [-20.0, 'track']],\n  ['control 2', [45, -6, False, 5, 55, 60], [0.0, 'night']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [-20, 0, False, 5, 55, 60], [60.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-50, -1, False, 3, 55, 60], [0.0, 'night']],\n  ['control 1', [55, 0, True, 5, 45, 60], [-45.0, 'dawn']],\n  ['control 2', [-70, -6, True, 5, 55, 50], [0.0, 'night']]]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"74c58c0fad2581ddc127d9d1f8e8b1a1c4ebe2bc34667e956ae6df93ccaeb92f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(ideal, sun_el, am, wake_el, east_lim, west_lim):\n    if sun_el <= 0:\n        return [0.0, 'night']\n    if sun_el < wake_el:\n        if am:\n            return [-float(east_lim), 'dawn']\n        return [float(west_lim), 'dusk']\n    return [float(max(-east_lim, min(west_lim, ideal))), 'track']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [70, 0, True, 3, 45, 50], [-45.0, 'dawn']],\n  ['regression: night boundary (partial repair)', [70, -1, True, 3, 45, 60], [0.0, 'night']],\n  ['control 1', [45, 5, False, 3, 45, 50], [45.0, 'track']],\n  ['control 2', [55, 3, True, 3, 50, 50], [50.0, 'track']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [70, 0, False, 3, 45, 60], [60.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-70, -1, False, 3, 50, 60], [0.0, 'night']],\n  ['control 1', [70, 5, False, 3, 50, 50], [50.0, 'track']],\n  ['control 2', [0, -6, True, 3, 50, 60], [0.0, 'night']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [45, 0, True, 5, 45, 60], [-45.0, 'dawn']],\n  ['regression: night boundary (partial repair)', [-20, -1, False, 3, 45, 50], [0.0, 'night']],\n  ['control 1', [0, 8, True, 5, 55, 50], [0.0, 'track']],\n  ['control 2', [-20, 0, False, 5, 55, 50], [50.0, 'dusk']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [-50, 0, False, 3, 55, 50], [50.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-20, -1, False, 3, 55, 50], [0.0, 'night']],\n  ['control 1', [-20, 3, False, 3, 45, 50], [-20.0, 'track']],\n  ['control 2', [45, -6, False, 5, 55, 60], [0.0, 'night']]],\n [['boundary: sun exactly on horizon', [-70, 0, True, 5, 50, 60], [-50.0, 'dawn']],\n  ['boundary: sun exactly at wake elevation', [-50, 5, True, 5, 50, 60], [-50.0, 'track']],\n  ['normal: evening park', [55, 2, False, 5, 50, 60], [60.0, 'dusk']],\n  ['regression: night boundary', [-20, 0, False, 5, 55, 60], [60.0, 'dusk']],\n  ['regression: night boundary (partial repair)', [-50, -1, False, 3, 55, 60], [0.0, 'night']],\n  ['control 1', [55, 0, True, 5, 45, 60], [-45.0, 'dawn']],\n  ['control 2', [-70, -6, True, 5, 55, 50], [0.0, 'night']]]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Deterministic stipulated toy contract for teaching; no claim of conformance with any standard, vendor protocol or production controller. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w2-solar_tracker_geometry-dawn-dusk-parking-night-boundary","generated_at":"2026-09-29T14:51:58.443141+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Single-axis and dual-axis solar trackers turn a sun direction into actuator commands; a sign, frame or limit mistake points a whole plant away from the sun or into a mechanical stop.","root_cause":"Elevation zero is classified as night.","sha256":"fa8705c80a78fb8c6047031d26861b6c71deced07151f9ade8cf8a60209d7a75","title":"Dawn and dusk parking positions: night boundary · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":41.114,"exit_code":1,"observations":[{"actual":[-50.0,"dawn"],"check":"boundary: sun exactly on horizon","expected":[-50.0,"dawn"],"passed":true},{"actual":[-50.0,"track"],"check":"boundary: sun exactly at wake elevation","expected":[-50.0,"track"],"passed":true},{"actual":[60.0,"dusk"],"check":"normal: evening park","expected":[60.0,"dusk"],"passed":true},{"actual":[-45.0,"dawn"],"check":"regression: night boundary","expected":[-45.0,"dawn"],"passed":true},{"actual":[-45.0,"dawn"],"check":"regression: night boundary (partial repair)","expected":[0.0,"night"],"passed":false},{"actual":[45.0,"track"],"check":"control 1","expected":[45.0,"track"],"passed":true},{"actual":[50.0,"track"],"check":"control 2","expected":[50.0,"track"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary: sun exactly on horizon\", \"actual\": [-50.0, \"dawn\"], \"expected\": [-50.0, \"dawn\"], \"passed\": true}, {\"check\": \"boundary: sun exactly at wake elevation\", \"actual\": [-50.0, \"track\"], \"expected\": [-50.0, \"track\"], \"passed\": true}, {\"check\": \"normal: evening park\", \"actual\": [60.0, \"dusk\"], \"expected\": [60.0, \"dusk\"], \"passed\": true}, {\"check\": \"regression: night boundary\", \"actual\": [-45.0, \"dawn\"], \"expected\": [-45.0, \"dawn\"], \"passed\": true}, {\"check\": \"regression: night boundary (partial repair)\", \"actual\": [-45.0, \"dawn\"], \"expected\": [0.0, \"night\"], \"passed\": false}, {\"check\": \"control 1\", \"actual\": [45.0, \"track\"], \"expected\": [45.0, \"track\"], \"passed\": true}, {\"check\": \"control 2\", \"actual\": [50.0, \"track\"], \"expected\": [50.0, \"track\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.461,"exit_code":1,"observations":[{"actual":[0.0,"night"],"check":"boundary: sun exactly on horizon","expected":[-50.0,"dawn"],"passed":false},{"actual":[-50.0,"track"],"check":"boundary: sun exactly at wake elevation","expected":[-50.0,"track"],"passed":true},{"actual":[60.0,"dusk"],"check":"normal: evening park","expected":[60.0,"dusk"],"passed":true},{"actual":[0.0,"night"],"check":"regression: night boundary","expected":[-45.0,"dawn"],"passed":false},{"actual":[0.0,"night"],"check":"regression: night boundary (partial repair)","expected":[0.0,"night"],"passed":true},{"actual":[45.0,"track"],"check":"control 1","expected":[45.0,"track"],"passed":true},{"actual":[50.0,"track"],"check":"control 2","expected":[50.0,"track"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary: sun exactly on horizon\", \"actual\": [0.0, \"night\"], \"expected\": [-50.0, \"dawn\"], \"passed\": false}, {\"check\": \"boundary: sun exactly at wake elevation\", \"actual\": [-50.0, \"track\"], \"expected\": [-50.0, \"track\"], \"passed\": true}, {\"check\": \"normal: evening park\", \"actual\": [60.0, \"dusk\"], \"expected\": [60.0, \"dusk\"], \"passed\": true}, {\"check\": \"regression: night boundary\", \"actual\": [0.0, \"night\"], \"expected\": [-45.0, \"dawn\"], \"passed\": false}, {\"check\": \"regression: night boundary (partial repair)\", \"actual\": [0.0, \"night\"], \"expected\": [0.0, \"night\"], \"passed\": true}, {\"check\": \"control 1\", \"actual\": [45.0, \"track\"], \"expected\": [45.0, \"track\"], \"passed\": true}, {\"check\": \"control 2\", \"actual\": [50.0, \"track\"], \"expected\": [50.0, \"track\"], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}