| --- |
| dataset_info: |
| features: |
| - name: query |
| dtype: string |
| - name: image |
| dtype: image |
| - name: annot |
| dtype: string |
| - name: reasoning |
| dtype: 'null' |
| - name: cate |
| dtype: string |
| - name: task |
| dtype: string |
| - name: metadata |
| dtype: string |
| splits: |
| - name: train |
| num_bytes: 22505811.0 |
| num_examples: 305 |
| - name: test |
| num_bytes: 5766701.0 |
| num_examples: 77 |
| download_size: 27997485 |
| dataset_size: 28272512.0 |
| configs: |
| - config_name: default |
| data_files: |
| - split: train |
| path: data/train-* |
| - split: test |
| path: data/test-* |
| task_categories: |
| - image-classification |
| license: other |
| tags: |
| - gear-fault-diagnosis |
| - gearbox |
| - vibration |
| - signal-to-image |
| - seu |
| - dds |
| - compute-then-check |
| pretty_name: SEU Gearset — Envelope-Modulation Spectrum (signal→VLM, Category C) |
| --- |
| # SEU gearset — gear-condition classification from the envelope-modulation spectrum (reasoning track) |
|
|
| First **gear** dataset in the AI4Manufacturing FORGE corpus (Category **C**, task **T-C1**). Each record is the **envelope-modulation spectrum** of a 4 s planetary-gearbox vibration window with the gear-train reference orders marked (shaft, carrier, sun-fault) — the representation for faithful **compute-then-check** CoT. `reasoning` is empty; the **`SEUG-annotated`** sibling fills it. |
|
|
| **Records:** 382 (splits {'train': 305, 'test': 77}); labels {'chipped': 80, 'health': 71, 'miss': 80, 'root': 78, 'surface': 73}; evidence_tier {'confirmed': 382}. |
| |
| ## Schema (7-field unified record) |
| | field | meaning | |
| |---|---| |
| | `query` | the classification instruction (one of 30 deterministic paraphrases per representation) | |
| | `image` | the rendered signal image (bytes embedded) | |
| | `annot` | gold gear condition: health / chipped / miss / root / surface | |
| | `reasoning` | chain-of-thought (empty here; filled in the `-annotated` sibling) | |
| | `cate` / `task` | `C` / `T-C1` (signal fault classification) | |
| | `metadata` | JSON string: representation, condition, file, window_idx, start_sample, channel, fs, fr_nominal, fr_used, fr_source, planetary, gear_lines, computed_verdict, computed_score, integer_score, family_obs, evidence_tier, image_sha256, split | |
| |
| ## Provenance & reproducibility |
| Generated **deterministically** by `forge_agent/examples/seu/convert.py` (`a990b2ef69`) → `forge_model/SEUG/convert_seug.py` (`8892ffb2db`); see `provenance.json`. |
|
|
| **Gold = filenames** (the files' internal Title fields are provably stale operator templates); the five gear conditions are **physically implanted** on the stage-1 sun gear of the DDS planetary gearbox [evidenced: every fault class modulates the mesh at the sun-fault order 5/6·fr] and are steady-state, so every window carries its file's condition. The gear-train constants (2-stage planetary 20/40×4/100 → 24/30×3/84, 27:1) were **derived from this dataset's own spectra** and validated against the manufacturer's published 27:1 ratio — tooth counts are not published anywhere. Confidence grades: **stage 1 high** (carrier line at exactly fr/6, sun-fault line at 5/6·fr, GMF₁ = 16.665 orders with dominant 2×/4× harmonics, valid 4-planet assembly), **stage 2 moderate** (GMF₂ = 3.111 orders at both speeds; sole assembly-valid candidate). Full chain + grades in `provenance.json` (`planetary_derivation`). |
|
|
| ## Caveats |
| - **The evidence tier is BINARY.** The label-independent detector (`mesh_modulation`) attests that *a gear fault is visibly present* (sun-fault-family modulation beating integer-order modulation) — it cannot name which of the four implanted subtypes, because all four share the same modulation signature. `confirmed` = binary agreement with the gold; subtype discrimination is learnable from these signals (deep-learning literature) but not physics-nameable. |
| - **Conflict rule (binary):** weak records are dropped only when the detector claims a fault on a `health` record; a quiet detector on a fault record is benign non-detection (kept in perception). |
| - **Split is time-stratified per file** (first 80% of each recording → train, last 20% → test): the rig has ONE physical specimen per (condition, speed-load) cell, so no unit-wise split exists. Cross-specimen generalization cannot be evaluated from this dataset. |
| - **Two operating conditions** (20 Hz-0 V, 30 Hz-2 V motor speed-load) are both included with condition metadata. |
|
|
| ## Source & license |
| Source: **SEU gearbox dataset** — Southeast University, Drivetrain Dynamics Simulator (SpectraQuest/Sumyoung DDS). Authors' research release: github.com/cathysiyu/Mechanical-datasets (no LICENSE file — cite the paper): S. Shao, S. McAleer, R. Yan, P. Baldi, *IEEE Trans. Industrial Informatics* 15(4):2446–2455, 2019 (DOI 10.1109/TII.2018.2864759). fs = 5120 Hz [evidenced: DAQ header × 2.56 convention + shaft combs at nominal in both conditions]. The release's `dataset/` folder (CWRU fan-end copies) is excluded — CWRU is published separately from its original source. |
