FA-12091 / Robotics frame conventions / Open access

Optical camera coordinates are mistaken for forward-left-up coordinates · case 01

Optical camera coordinates are mistaken for forward-left-up coordinates.

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

ROOT CAUSE

The camera optical x-right/y-down/z-forward tuple is copied into a body x-forward/y-left/z-up interface.

VERIFIED REPAIR

Apply the signed optical-to-body permutation [z,-x,-y].

Unsuccessful approach: Reordering axes without reversing right and down leaves two mirrored body axes.

Case contract

For integer optical [right,down,forward], return body [forward,left,up] at the same origin.

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('right axis', solve([N,0,0]), [0,-N,0])
check('down axis', solve([0,N,0]), [0,0,-N])
check('forward axis', solve([0,0,N]), [N,0,0])
check('origin', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [3*N,-N,-2*N])
check('negative axes', solve([-N,-2*N,-3*N]), [-3*N,N,2*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
right axis	`[1, 0, 0]`	`[0, -1, 0]`	Failed
down axis	`[0, 1, 0]`	`[0, 0, -1]`	Failed
forward axis	`[0, 0, 1]`	`[1, 0, 0]`	Failed
origin	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[1, 2, 3]`	`[3, -1, -2]`	Failed
negative axes	`[-1, -2, -3]`	`[-3, 1, 2]`	Failed

SHA-256 / df74a45155c2c6d6ad2c539e2360df9595103911e8d3b09e8304378e810f3ab9

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[2],v[0],v[1]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('right axis', solve([N,0,0]), [0,-N,0])
check('down axis', solve([0,N,0]), [0,0,-N])
check('forward axis', solve([0,0,N]), [N,0,0])
check('origin', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [3*N,-N,-2*N])
check('negative axes', solve([-N,-2*N,-3*N]), [-3*N,N,2*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
right axis	`[0, 1, 0]`	`[0, -1, 0]`	Failed
down axis	`[0, 0, 1]`	`[0, 0, -1]`	Failed
forward axis	`[1, 0, 0]`	`[1, 0, 0]`	Passed
origin	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[3, 1, 2]`	`[3, -1, -2]`	Failed
negative axes	`[-3, -1, -2]`	`[-3, 1, 2]`	Failed

SHA-256 / 24f04c7c2f41e88006342251b75d341c38807103d33e3a6504a897e9795822d6

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[2],-v[0],-v[1]]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('right axis', solve([N,0,0]), [0,-N,0])
check('down axis', solve([0,N,0]), [0,0,-N])
check('forward axis', solve([0,0,N]), [N,0,0])
check('origin', solve([0,0,0]), [0,0,0])
check('mixed', solve([N,2*N,3*N]), [3*N,-N,-2*N])
check('negative axes', solve([-N,-2*N,-3*N]), [-3*N,N,2*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
right axis	`[0, -1, 0]`	`[0, -1, 0]`	Passed
down axis	`[0, 0, -1]`	`[0, 0, -1]`	Passed
forward axis	`[1, 0, 0]`	`[1, 0, 0]`	Passed
origin	`[0, 0, 0]`	`[0, 0, 0]`	Passed
mixed	`[3, -1, -2]`	`[3, -1, -2]`	Passed
negative axes	`[-3, 1, 2]`	`[-3, 1, 2]`	Passed

SHA-256 / c5bcee152965bc7917b00c82e1e6db5a6910b71ef88c362defd5762160bd6c5a

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 2026-09-29T14:38:53.688683+00:00.

Case digest / 0086532d5cb2bafdd0263ab71bb5408745a6c8f564cbf17c7025c2e1955cd6c5