FA-12136 / Robotics frame conventions / Open access

A static mounting transform expires like a sampled pose · case 01

A static mounting transform expires like a sampled pose.

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

ROOT CAUSE

The timestamp tolerance is applied to a static calibration edge.

VERIFIED REPAIR

Static edges remain valid; dynamic edges require an exact timestamp in this no-interpolation model.

Unsuccessful approach: Ignoring timestamps for every edge also admits stale dynamic transforms.

Case contract

Return translation if an edge is static or its sample_time equals requested_time; otherwise None. No interpolation or extrapolation is permitted for dynamic edges.

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(translation,is_static,sample_time,requested_time):
    return translation if sample_time==requested_time else None
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('old static calibration', solve([N,0],True,0,100+N), [N,0])
check('stale dynamic', solve([N,0],False,0,100+N), None)
check('exact dynamic', solve([N,N],False,N,N), [N,N])
check('future dynamic', solve([N,0],False,N+1,N), None)
check('static earlier query', solve([N,-N],True,100+N,0), [N,-N])
check('zero time dynamic', solve([0,0],False,0,0), [0,0])
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
old static calibration	`None`	`[1, 0]`	Failed
stale dynamic	`None`	`None`	Passed
exact dynamic	`[1, 1]`	`[1, 1]`	Passed
future dynamic	`None`	`None`	Passed
static earlier query	`None`	`[1, -1]`	Failed
zero time dynamic	`[0, 0]`	`[0, 0]`	Passed

SHA-256 / 2caec7363a5192cb0b804e1bebc9f38aa7fd743b6fc27af2bdffd08d8a9b9066

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(translation,is_static,sample_time,requested_time):
    return translation
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('old static calibration', solve([N,0],True,0,100+N), [N,0])
check('stale dynamic', solve([N,0],False,0,100+N), None)
check('exact dynamic', solve([N,N],False,N,N), [N,N])
check('future dynamic', solve([N,0],False,N+1,N), None)
check('static earlier query', solve([N,-N],True,100+N,0), [N,-N])
check('zero time dynamic', solve([0,0],False,0,0), [0,0])
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
old static calibration	`[1, 0]`	`[1, 0]`	Passed
stale dynamic	`[1, 0]`	`None`	Failed
exact dynamic	`[1, 1]`	`[1, 1]`	Passed
future dynamic	`[1, 0]`	`None`	Failed
static earlier query	`[1, -1]`	`[1, -1]`	Passed
zero time dynamic	`[0, 0]`	`[0, 0]`	Passed

SHA-256 / adf31993fa5068732742cb40fabe87dbf4c8b348c3dbfd791630e54d3e670a2f

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(translation,is_static,sample_time,requested_time):
    return translation if is_static or sample_time==requested_time else None
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('old static calibration', solve([N,0],True,0,100+N), [N,0])
check('stale dynamic', solve([N,0],False,0,100+N), None)
check('exact dynamic', solve([N,N],False,N,N), [N,N])
check('future dynamic', solve([N,0],False,N+1,N), None)
check('static earlier query', solve([N,-N],True,100+N,0), [N,-N])
check('zero time dynamic', solve([0,0],False,0,0), [0,0])
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
old static calibration	`[1, 0]`	`[1, 0]`	Passed
stale dynamic	`None`	`None`	Passed
exact dynamic	`[1, 1]`	`[1, 1]`	Passed
future dynamic	`None`	`None`	Passed
static earlier query	`[1, -1]`	`[1, -1]`	Passed
zero time dynamic	`[0, 0]`	`[0, 0]`	Passed

SHA-256 / 36ce57af3c162b1a8374bf65b6c0dea1b7a83580cfbc2da60285fb95086a1ee8

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 2026-09-29T14:38:54.235031+00:00.

Case digest / cd88a9f1a4f2186d39e106fd8d806494ff51ec27b4ef98de90e50947438c3aa3