FA-67656 / Elevator dispatch scheduling / Open access

Door obstruction reopen and nudging: continuous blockage timer · case 01

A curtain held blocked never triggers nudging, or brief separate obstructions add up to a long blockage.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Every obstruction restarts the blockage timer.

VERIFIED REPAIR

Start the timer at the first obstruction of an unbroken blockage and clear it on unblock.

Unsuccessful approach: Ignoring unblock measures from an obstruction that has since been cleared.

Case contract

During a door cycle each light-curtain obstruction reopens the doors and counts; the third obstruction, or an obstruction while the curtain has been blocked continuously for 20 s or more since the first unbroken obstruction, starts nudging (slow close, curtain ignored). While nudging, curtain obstructions are ignored. The mechanical safety edge always reopens and does not affect counting. unblock ends a continuous blockage. closed ends the cycle and resets everything.

Why this case matters

Lift group controllers make these decisions many times per minute; a wrong answer strands passengers, wastes trips or overrides a safety rule.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    count = 0
    nudge = False
    block_start = None
    out = []
    for t, ev in x['events']:
        if ev == 'obstruct':
            block_start = t
            if nudge:
                out.append('ignored')
            else:
                count += 1
                if count >= 3 or t - block_start >= 20:
                    nudge = True
                    out.append('nudge')
                else:
                    out.append('reopen')
        elif ev == 'unblock':
            block_start = None
        elif ev == 'edge':
            out.append('reopen')
        elif ev == 'closed':
            count = 0
            nudge = False
            block_start = None
            out.append('done')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 1', {'events': [[8, 'obstruct'], [13, 'closed'], [18, 'obstruct'], [26, 'edge'], [28, 'obstruct'], [29, 'obstruct'], [41, 'obstruct'], [42, 'obstruct'], [54, 'obstruct'], [66, 'closed']]}, ['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']), ('control 4', {'events': [[5, 'edge'], [10, 'unblock'], [11, 'obstruct'], [19, 'closed']]}, ['reopen', 'reopen', 'done']), ('control 7', {'events': [[2, 'unblock'], [10, 'edge'], [18, 'obstruct'], [23, 'unblock'], [28, 'edge'], [33, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'reopen'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: edge contacts do not count', {'events': [[1, 'obstruct'], [2, 'edge'], [3, 'unblock'], [4, 'obstruct'], [5, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen']), ('control 12', {'events': [[5, 'obstruct'], [13, 'edge'], [15, 'unblock'], [16, 'obstruct'], [21, 'unblock'], [22, 'edge'], [30, 'closed'], [32, 'obstruct'], [44, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen']), ('control 15', {'events': [[8, 'obstruct'], [9, 'obstruct'], [10, 'obstruct'], [11, 'unblock'], [16, 'obstruct'], [24, 'obstruct'], [29, 'edge']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'reopen']), ('control 18', {'events': [[12, 'obstruct'], [20, 'obstruct'], [22, 'obstruct']]}, ['reopen', 'reopen', 'nudge'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 65', {'events': [[1, 'obstruct'], [13, 'edge'], [25, 'obstruct'], [37, 'unblock']]}, ['reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: curtain broken then blocked again', {'events': [[0, 'obstruct'], [5, 'unblock'], [15, 'obstruct'], [26, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 23', {'events': [[1, 'unblock'], [6, 'unblock'], [18, 'obstruct'], [30, 'closed']]}, ['reopen', 'done']), ('control 26', {'events': [[12, 'closed'], [13, 'closed'], [15, 'obstruct'], [17, 'obstruct'], [19, 'obstruct']]}, ['done', 'done', 'reopen', 'reopen', 'nudge']), ('control 29', {'events': [[8, 'edge'], [10, 'obstruct'], [12, 'obstruct'], [20, 'closed']]}, ['reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: closing clears nudging', {'events': [[0, 'obstruct'], [1, 'obstruct'], [2, 'obstruct'], [3, 'closed'], [4, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'done', 'reopen']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 34', {'events': [[8, 'edge'], [16, 'obstruct'], [24, 'obstruct'], [36, 'closed'], [48, 'obstruct'], [60, 'obstruct'], [62, 'obstruct'], [64, 'unblock'], [72, 'obstruct'], [80, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen', 'nudge', 'ignored']), ('control 37', {'events': [[2, 'closed'], [4, 'closed'], [9, 'obstruct'], [21, 'edge']]}, ['done', 'done', 'reopen', 'reopen']), ('control 40', {'events': [[2, 'closed'], [7, 'obstruct'], [15, 'edge'], [16, 'obstruct'], [18, 'closed']]}, ['done', 'reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 45', {'events': [[5, 'edge'], [17, 'closed'], [22, 'obstruct'], [24, 'closed']]}, ['reopen', 'done', 'reopen', 'done']), ('control 48', {'events': [[2, 'obstruct'], [7, 'obstruct'], [15, 'obstruct'], [27, 'obstruct'], [35, 'unblock']]}, ['reopen', 'reopen', 'nudge', 'ignored']), ('control 51', {'events': [[8, 'closed'], [9, 'closed'], [14, 'obstruct'], [26, 'closed'], [38, 'obstruct']]}, ['done', 'done', 'reopen', 'done', 'reopen'])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
regression: curtain held for twenty seconds	`['reopen', 'reopen']`	`['reopen', 'nudge']`	Failed
control 10	`['reopen', 'reopen', 'reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'reopen', 'reopen', 'nudge']`	Passed
control 64	`['reopen', 'reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'reopen', 'nudge']`	Passed
boundary: third obstruction	`['reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'nudge']`	Passed
boundary: safety edge while nudging	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	Passed
control 1	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	Passed
control 4	`['reopen', 'reopen', 'done']`	`['reopen', 'reopen', 'done']`	Passed
control 7	`['reopen', 'reopen', 'reopen', 'reopen']`	`['reopen', 'reopen', 'reopen', 'reopen']`	Passed

SHA-256 / 4a2e333ddecb75e797c8daeba445eeb0c1a70f74216c9a0dccd0f1936489a6e0

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    count = 0
    nudge = False
    block_start = None
    out = []
    for t, ev in x['events']:
        if ev == 'obstruct':
            if block_start is None:
                block_start = t
            if nudge:
                out.append('ignored')
            else:
                count += 1
                if count >= 3 or t - block_start >= 20:
                    nudge = True
                    out.append('nudge')
                else:
                    out.append('reopen')
        elif ev == 'unblock':
            pass
        elif ev == 'edge':
            out.append('reopen')
        elif ev == 'closed':
            count = 0
            nudge = False
            block_start = None
            out.append('done')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 1', {'events': [[8, 'obstruct'], [13, 'closed'], [18, 'obstruct'], [26, 'edge'], [28, 'obstruct'], [29, 'obstruct'], [41, 'obstruct'], [42, 'obstruct'], [54, 'obstruct'], [66, 'closed']]}, ['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']), ('control 4', {'events': [[5, 'edge'], [10, 'unblock'], [11, 'obstruct'], [19, 'closed']]}, ['reopen', 'reopen', 'done']), ('control 7', {'events': [[2, 'unblock'], [10, 'edge'], [18, 'obstruct'], [23, 'unblock'], [28, 'edge'], [33, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'reopen'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: edge contacts do not count', {'events': [[1, 'obstruct'], [2, 'edge'], [3, 'unblock'], [4, 'obstruct'], [5, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen']), ('control 12', {'events': [[5, 'obstruct'], [13, 'edge'], [15, 'unblock'], [16, 'obstruct'], [21, 'unblock'], [22, 'edge'], [30, 'closed'], [32, 'obstruct'], [44, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen']), ('control 15', {'events': [[8, 'obstruct'], [9, 'obstruct'], [10, 'obstruct'], [11, 'unblock'], [16, 'obstruct'], [24, 'obstruct'], [29, 'edge']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'reopen']), ('control 18', {'events': [[12, 'obstruct'], [20, 'obstruct'], [22, 'obstruct']]}, ['reopen', 'reopen', 'nudge'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 65', {'events': [[1, 'obstruct'], [13, 'edge'], [25, 'obstruct'], [37, 'unblock']]}, ['reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: curtain broken then blocked again', {'events': [[0, 'obstruct'], [5, 'unblock'], [15, 'obstruct'], [26, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 23', {'events': [[1, 'unblock'], [6, 'unblock'], [18, 'obstruct'], [30, 'closed']]}, ['reopen', 'done']), ('control 26', {'events': [[12, 'closed'], [13, 'closed'], [15, 'obstruct'], [17, 'obstruct'], [19, 'obstruct']]}, ['done', 'done', 'reopen', 'reopen', 'nudge']), ('control 29', {'events': [[8, 'edge'], [10, 'obstruct'], [12, 'obstruct'], [20, 'closed']]}, ['reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: closing clears nudging', {'events': [[0, 'obstruct'], [1, 'obstruct'], [2, 'obstruct'], [3, 'closed'], [4, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'done', 'reopen']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 34', {'events': [[8, 'edge'], [16, 'obstruct'], [24, 'obstruct'], [36, 'closed'], [48, 'obstruct'], [60, 'obstruct'], [62, 'obstruct'], [64, 'unblock'], [72, 'obstruct'], [80, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen', 'nudge', 'ignored']), ('control 37', {'events': [[2, 'closed'], [4, 'closed'], [9, 'obstruct'], [21, 'edge']]}, ['done', 'done', 'reopen', 'reopen']), ('control 40', {'events': [[2, 'closed'], [7, 'obstruct'], [15, 'edge'], [16, 'obstruct'], [18, 'closed']]}, ['done', 'reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 45', {'events': [[5, 'edge'], [17, 'closed'], [22, 'obstruct'], [24, 'closed']]}, ['reopen', 'done', 'reopen', 'done']), ('control 48', {'events': [[2, 'obstruct'], [7, 'obstruct'], [15, 'obstruct'], [27, 'obstruct'], [35, 'unblock']]}, ['reopen', 'reopen', 'nudge', 'ignored']), ('control 51', {'events': [[8, 'closed'], [9, 'closed'], [14, 'obstruct'], [26, 'closed'], [38, 'obstruct']]}, ['done', 'done', 'reopen', 'done', 'reopen'])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
regression: curtain held for twenty seconds	`['reopen', 'nudge']`	`['reopen', 'nudge']`	Passed
control 10	`['reopen', 'reopen', 'reopen', 'nudge', 'ignored']`	`['reopen', 'reopen', 'reopen', 'reopen', 'nudge']`	Failed
control 64	`['reopen', 'reopen', 'nudge', 'ignored']`	`['reopen', 'reopen', 'reopen', 'nudge']`	Failed
boundary: third obstruction	`['reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'nudge']`	Passed
boundary: safety edge while nudging	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	Passed
control 1	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	Passed
control 4	`['reopen', 'reopen', 'done']`	`['reopen', 'reopen', 'done']`	Passed
control 7	`['reopen', 'reopen', 'reopen', 'reopen']`	`['reopen', 'reopen', 'reopen', 'reopen']`	Passed

SHA-256 / 9ac6aed35572edf21b0cf5932fbf7791d6537c3cd87eac95bbccd0784de1b405

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    count = 0
    nudge = False
    block_start = None
    out = []
    for t, ev in x['events']:
        if ev == 'obstruct':
            if block_start is None:
                block_start = t
            if nudge:
                out.append('ignored')
            else:
                count += 1
                if count >= 3 or t - block_start >= 20:
                    nudge = True
                    out.append('nudge')
                else:
                    out.append('reopen')
        elif ev == 'unblock':
            block_start = None
        elif ev == 'edge':
            out.append('reopen')
        elif ev == 'closed':
            count = 0
            nudge = False
            block_start = None
            out.append('done')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 1', {'events': [[8, 'obstruct'], [13, 'closed'], [18, 'obstruct'], [26, 'edge'], [28, 'obstruct'], [29, 'obstruct'], [41, 'obstruct'], [42, 'obstruct'], [54, 'obstruct'], [66, 'closed']]}, ['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']), ('control 4', {'events': [[5, 'edge'], [10, 'unblock'], [11, 'obstruct'], [19, 'closed']]}, ['reopen', 'reopen', 'done']), ('control 7', {'events': [[2, 'unblock'], [10, 'edge'], [18, 'obstruct'], [23, 'unblock'], [28, 'edge'], [33, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'reopen'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: edge contacts do not count', {'events': [[1, 'obstruct'], [2, 'edge'], [3, 'unblock'], [4, 'obstruct'], [5, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen']), ('control 12', {'events': [[5, 'obstruct'], [13, 'edge'], [15, 'unblock'], [16, 'obstruct'], [21, 'unblock'], [22, 'edge'], [30, 'closed'], [32, 'obstruct'], [44, 'edge']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen']), ('control 15', {'events': [[8, 'obstruct'], [9, 'obstruct'], [10, 'obstruct'], [11, 'unblock'], [16, 'obstruct'], [24, 'obstruct'], [29, 'edge']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'reopen']), ('control 18', {'events': [[12, 'obstruct'], [20, 'obstruct'], [22, 'obstruct']]}, ['reopen', 'reopen', 'nudge'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 65', {'events': [[1, 'obstruct'], [13, 'edge'], [25, 'obstruct'], [37, 'unblock']]}, ['reopen', 'reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: curtain broken then blocked again', {'events': [[0, 'obstruct'], [5, 'unblock'], [15, 'obstruct'], [26, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 23', {'events': [[1, 'unblock'], [6, 'unblock'], [18, 'obstruct'], [30, 'closed']]}, ['reopen', 'done']), ('control 26', {'events': [[12, 'closed'], [13, 'closed'], [15, 'obstruct'], [17, 'obstruct'], [19, 'obstruct']]}, ['done', 'done', 'reopen', 'reopen', 'nudge']), ('control 29', {'events': [[8, 'edge'], [10, 'obstruct'], [12, 'obstruct'], [20, 'closed']]}, ['reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('boundary: closing clears nudging', {'events': [[0, 'obstruct'], [1, 'obstruct'], [2, 'obstruct'], [3, 'closed'], [4, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'done', 'reopen']), ('boundary: third obstruction', {'events': [[1, 'obstruct'], [2, 'unblock'], [3, 'obstruct'], [4, 'unblock'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge']), ('control 34', {'events': [[8, 'edge'], [16, 'obstruct'], [24, 'obstruct'], [36, 'closed'], [48, 'obstruct'], [60, 'obstruct'], [62, 'obstruct'], [64, 'unblock'], [72, 'obstruct'], [80, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'done', 'reopen', 'reopen', 'nudge', 'ignored']), ('control 37', {'events': [[2, 'closed'], [4, 'closed'], [9, 'obstruct'], [21, 'edge']]}, ['done', 'done', 'reopen', 'reopen']), ('control 40', {'events': [[2, 'closed'], [7, 'obstruct'], [15, 'edge'], [16, 'obstruct'], [18, 'closed']]}, ['done', 'reopen', 'reopen', 'reopen', 'done'])], [('regression: curtain held for twenty seconds', {'events': [[0, 'obstruct'], [20, 'obstruct']]}, ['reopen', 'nudge']), ('control 10', {'events': [[8, 'edge'], [13, 'obstruct'], [18, 'edge'], [30, 'unblock'], [35, 'obstruct'], [40, 'obstruct'], [42, 'unblock']]}, ['reopen', 'reopen', 'reopen', 'reopen', 'nudge']), ('sampled regression 3', {'events': [[1, 'obstruct'], [13, 'edge'], [21, 'obstruct'], [26, 'unblock'], [27, 'obstruct'], [32, 'edge'], [40, 'obstruct'], [48, 'obstruct'], [56, 'unblock'], [64, 'closed']]}, ['reopen', 'reopen', 'nudge', 'ignored', 'reopen', 'ignored', 'ignored', 'done']), ('control 64', {'events': [[8, 'obstruct'], [13, 'edge'], [18, 'unblock'], [26, 'unblock'], [34, 'obstruct'], [36, 'obstruct']]}, ['reopen', 'reopen', 'reopen', 'nudge']), ('boundary: safety edge while nudging', {'events': [[1, 'obstruct'], [2, 'obstruct'], [3, 'obstruct'], [4, 'edge'], [5, 'obstruct']]}, ['reopen', 'reopen', 'nudge', 'reopen', 'ignored']), ('control 45', {'events': [[5, 'edge'], [17, 'closed'], [22, 'obstruct'], [24, 'closed']]}, ['reopen', 'done', 'reopen', 'done']), ('control 48', {'events': [[2, 'obstruct'], [7, 'obstruct'], [15, 'obstruct'], [27, 'obstruct'], [35, 'unblock']]}, ['reopen', 'reopen', 'nudge', 'ignored']), ('control 51', {'events': [[8, 'closed'], [9, 'closed'], [14, 'obstruct'], [26, 'closed'], [38, 'obstruct']]}, ['done', 'done', 'reopen', 'done', 'reopen'])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
regression: curtain held for twenty seconds	`['reopen', 'nudge']`	`['reopen', 'nudge']`	Passed
control 10	`['reopen', 'reopen', 'reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'reopen', 'reopen', 'nudge']`	Passed
control 64	`['reopen', 'reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'reopen', 'nudge']`	Passed
boundary: third obstruction	`['reopen', 'reopen', 'nudge']`	`['reopen', 'reopen', 'nudge']`	Passed
boundary: safety edge while nudging	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	`['reopen', 'reopen', 'nudge', 'reopen', 'ignored']`	Passed
control 1	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	`['reopen', 'done', 'reopen', 'reopen', 'reopen', 'nudge', 'ignored', 'ignored', 'ignored', 'done']`	Passed
control 4	`['reopen', 'reopen', 'done']`	`['reopen', 'reopen', 'done']`	Passed
control 7	`['reopen', 'reopen', 'reopen', 'reopen']`	`['reopen', 'reopen', 'reopen', 'reopen']`	Passed

SHA-256 / 7841febe5de2535c38704f8b5316e9b96286bab9e12a95114dba65ee18cf19bd

Verification & scope

Stipulated toy lift-control contract for a bounded teaching model; it makes no claim of conformance to any lift code or vendor dispatcher and omits real safety cases. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:47:55.003040+00:00.

Case digest / d8bbbc96d22a98e2a5752a0f18c2316c9406ef355170edad1e986fac434636ea