license: cc-by-4.0
task_categories:
- robotics
tags:
- LeRobot
- world-model
- robot-failure
- manipulation
- franka
- panda
- counterfactual
configs:
- config_name: default
data_files: data/*/*.parquet
FailBench wm1 — a world-model corpus of robot actuator failures
66,480 episodes · 7.3M frames · 5.5 s each · 20 fps · 640×480 · Franka Panda
Each episode shows a robot mid-task, an actuator fault firing at a known instant, and the five seconds that follow. The fault is given as an 8-dim vector, per frame — all-zero before the onset, constant after — so a model can be asked "if these joints go limp here, what happens next?" before anything has happened.
Built in MuJoCo on top of LIBERO and RoboCasa teleoperation demos.
from lerobot.datasets.lerobot_dataset import LeRobotDataset
past = [-0.15, -0.10, -0.05, 0.0] # 4 observed frames
future = [0.05 * i for i in range(1, 9)] # 8 predicted frames
ds = LeRobotDataset(
"aaronngx/failbench-wm1",
delta_timestamps={k: past + future for k in
("observation.images.agentview", "observation.state",
"action", "fault")},
)
s = ds[0]
s["observation.images.agentview"] # (12, 3, 480, 640)
s["fault"] # (12, 8) -> zeros, then the fault
s["task"] # "Pick the mug ... the shoulder joint loses actuation ..."
The onset is always frame 10, so a window anchored before it has the fault firing inside the prediction horizon — observed frames pre-failure, target frames post-failure.
Features
| feature | dtype | shape | notes |
|---|---|---|---|
observation.images.agentview |
video | [3,480,640] |
scene view, camera randomised per demo |
observation.images.wrist |
video | [3,480,640] |
hand-mounted (72% of the download) |
observation.state |
float32 | [9] |
7 arm joints + 2 finger positions |
action |
float32 | [7] |
the PD target that actually drove the physics |
action.demo |
float32 | [7] |
the operator's recorded action |
fault |
float32 | [8] |
[j1…j7, gripper], per frame |
task |
string | the natural-language prompt (62,883 distinct) |
action[k] precedes frame[k] — apply no shift. The value at index k is the
control in force during the physics steps that end at frame k. The source
LIBERO/RoboCasa demos use the opposite convention (an action at t takes effect
at t+1), but this corpus never replays recorded actions — it drives a PD target
and logs the operator action alongside. Shifting introduces the off-by-one it
appears to fix.
observation.state is robot-only and fixed-width; the underlying sim qpos is
scene-dependent (41–110 columns) and cannot be a fixed-shape feature. End-effector
position is omitted because it is a deterministic function of the arm joints.
Composition
| LIBERO / RoboCasa | 27,000 / 39,480 episodes |
| demos · tasks · distinct scenes | 1,108 · 50 · 968 |
| nominal (fault = all zeros) | 2,297 |
| failure cells covered | 383 of 383, 163–172 episodes each |
| train / val | 59,880 / 6,600 (split by demo, never by episode) |
Failure coverage is round-robin over the cell lattice (127 non-empty joint
subsets × 3 gripper states, plus 2 gripper-only), so coverage is exact by
construction rather than by sampling. The number of failed joints is therefore
binomial, not uniform — {0: 2632, 1: 3526, 2: 10563, 3: 17560, 4: 17604, 5: 10558, 6: 3530, 7: 507}. Each episode carries failure_prob, the realistic
fault prior, for importance reweighting.
Per-episode metadata in meta/episodes/: trial_id, source, task_name, demo_uid, failure_key, failed_joints, n_failed_joints, gripper_mode, fail_idx, traj_progress, cam_variant, failure_prob, is_nominal, is_holding, held_at_onset, onset_frame, split.
Matched controls
Slot 0 of each timestep is a nominal run from the same demo at the same instant as its five failures, so a difference between them is attributable to the fault rather than to arm pose or task phase. 2,297 such groups share a single camera and are pixel-comparable — their pre-failure frames agree to 0.17 grey levels.
Known defect — the gripper channel on RoboCasa
For episodes holding an object at the failure instant, RoboCasa loses the object almost regardless of the fault:
| gripper mode | LIBERO released by t=5 s | RoboCasa released |
|---|---|---|
none (no gripper fault) |
4% | 88% |
slip |
60% | 94% |
open |
64% | 96% |
A grasp does not survive being teleported into: the sim state is written directly, discarding the contact history that held the object, while the finger actuators sit at a command that means fully closed — squeezing RoboCasa's ~5.4 cm objects out of the grasp. LIBERO's ~1.7 cm objects survive it.
Filter with held_at_onset for anything predicting pixels or object motion:
import pandas as pd
eps = pd.read_parquet("meta/episodes/chunk-000/file-000.parquet")
clean = eps[(eps.source == "libero") | (~eps.held_at_onset)] # 49,146 episodes
This costs no diversity — the same demos also produce non-holding episodes, so all 1,108 scenes and every task survive.
Arm-joint conditioning is unaffected, being a separate actuator path: failed joints deviate from the commanded target 14.2× (LIBERO) / 16.5× (RoboCasa) more than healthy ones. If joint failure is what you are modelling, the corpus is sound as published.
Other caveats
- A nominal episode is simulated, not replayed. Only the 10 context frames reproduce the source demo exactly; the rest is re-simulated with a PD tracker and drifts (LIBERO 0.009 rad / 0.011 m, RoboCasa 0.025 rad / 0.055 m, mean over the branch). This is deliberate — a matched control must run through the same dynamics as its failures — but nominals are not ground truth for what the operator did next.
- Limp-failure semantics model brake failure, not a typical Franka fault (a real Panda has failsafe brakes). A worst-case envelope, which suits a safety planner, but say so in any writeup.
- Both corpora are Panda (RoboCasa uses
PandaMobile), so this tests scene, task and camera transfer — not cross-embodiment transfer. torchcodecmay fail to load depending on your torch/ffmpeg build. Passvideo_backend="pyav"if so; it is a decoder issue, not a dataset issue.
Partial download
The wrist stream is 33 GB of the 46 GB total:
from huggingface_hub import snapshot_download
snapshot_download("aaronngx/failbench-wm1", repo_type="dataset",
allow_patterns=["meta/*", "data/*",
"videos/observation.images.agentview/*"])
Stock LeRobotDataset expects every declared video feature to be present, so an
agentview-only checkout needs observation.images.wrist removed from the local
meta/info.json.
Provenance
Generated with MuJoCo 3.3.4 at 640×480, H.264 CRF 20, 20 Hz (robosuite's control
timestep of 1/20 over a 0.002 s physics step). The branch is exactly 5.000 s —
2,500 mj_step sampled every 25. Video was stream-copied into LeRobot v3 shards
without re-encoding, and verified to decode bit-identically to the source clips.
Built on LIBERO and RoboCasa; please cite those alongside this dataset.