FA-12096 / Robotics frame conventions / Open access

North-east-down positions are labeled as east-north-up · case 01

North-east-down positions are labeled as east-north-up.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The navigation adapter changes the frame label without changing coordinates.

VERIFIED REPAIR

Swap horizontal components and negate down.

Unsuccessful approach: Swapping north and east alone preserves the wrong vertical sign.

Case contract

Convert integer local NED [north,east,down] to ENU [east,north,up] with coincident origins.

Why this case matters

Robot adapters must preserve the declared frame, reference point, and representation conventions across interfaces.

1 / The failure

Exit 1

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

def rot(v, q):
    x,y = v
    return [(x,y),(-y,x),(-x,-y),(y,-x)][q%4]

N = 1
observations = []
def solve(v):
    return v
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('north', solve([N,0,0]), [0,N,0])
check('east', solve([0,N,0]), [N,0,0])
check('down', solve([0,0,N]), [0,0,-N])
check('zero', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [2*N,N,-3*N])
check('up', solve([-N,0,-N]), [0,-N,N])
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
north	`[1, 0, 0]`	`[0, 1, 0]`	Failed
east	`[0, 1, 0]`	`[1, 0, 0]`	Failed
down	`[0, 0, 1]`	`[0, 0, -1]`	Failed
zero	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[1, 2, 3]`	`[2, 1, -3]`	Failed
up	`[-1, 0, -1]`	`[0, -1, 1]`	Failed

SHA-256 / da497c5c5d4f82648998f7a90ff369d096cf321d27fbb22922a132d29521858f

2 / The unsuccessful fix

Exit 1

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

def rot(v, q):
    x,y = v
    return [(x,y),(-y,x),(-x,-y),(y,-x)][q%4]

N = 1
observations = []
def solve(v):
    return [v[1],v[0],v[2]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('north', solve([N,0,0]), [0,N,0])
check('east', solve([0,N,0]), [N,0,0])
check('down', solve([0,0,N]), [0,0,-N])
check('zero', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [2*N,N,-3*N])
check('up', solve([-N,0,-N]), [0,-N,N])
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
north	`[0, 1, 0]`	`[0, 1, 0]`	Passed
east	`[1, 0, 0]`	`[1, 0, 0]`	Passed
down	`[0, 0, 1]`	`[0, 0, -1]`	Failed
zero	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[2, 1, 3]`	`[2, 1, -3]`	Failed
up	`[0, -1, -1]`	`[0, -1, 1]`	Failed

SHA-256 / 4418732f97fb8c58786c52ce072af1b8158466b9782e492b42e63291ee311101

3 / The verified repair

Exit 0

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

def rot(v, q):
    x,y = v
    return [(x,y),(-y,x),(-x,-y),(y,-x)][q%4]

N = 1
observations = []
def solve(v):
    return [v[1],v[0],-v[2]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('north', solve([N,0,0]), [0,N,0])
check('east', solve([0,N,0]), [N,0,0])
check('down', solve([0,0,N]), [0,0,-N])
check('zero', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [2*N,N,-3*N])
check('up', solve([-N,0,-N]), [0,-N,N])
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
north	`[0, 1, 0]`	`[0, 1, 0]`	Passed
east	`[1, 0, 0]`	`[1, 0, 0]`	Passed
down	`[0, 0, -1]`	`[0, 0, -1]`	Passed
zero	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[2, 1, -3]`	`[2, 1, -3]`	Passed
up	`[0, -1, 1]`	`[0, -1, 1]`	Passed

SHA-256 / f89834ce93cd27b5c8b0b560c05a848a70a01c70395052430c7dd7b787eb236d

Verification & scope

Small exact offline frame model; not a robot middleware implementation or continuous pose estimator. 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 2026-09-29T14:38:53.696272+00:00.

Case digest / fa5f548ef59b474b20d40f23b25613c500112ad0f2640f070df341b7b41a00cf