transformer-base
A transformer maneuver detector for maneuver-detect.
It localises maneuvers in a satellite's mean-element TLE history; the same vis-viva / Gauss physics
inversion the classical detector uses then recovers the ฮv magnitude and maneuver type for each
detection (the model localises, the physics inverts).
How to use
The checkpoint is fetched from this repo automatically on first use โ CPU-only, cached on disk, no weights at install time:
from maneuver_detect import detect, datasets
history = datasets.tle_history(norad_id=25544, start="2024-01-01")
maneuvers = detect(history, model="transformer-base")
# DataFrame columns: epoch, confidence, type, delta_v_estimate, plus provenance
Model description
- Architecture: transformer sequence network, 9,486,337 parameters.
- Input: the frozen irregular-sampling encoding (time-encoded element deltas, no interpolation); inputs are standardised with the train-split per-class statistics frozen into this checkpoint, so inference reproduces training-time standardisation.
- Window / stride: 64 / 32.
- Default detection threshold: 0.400.
- Per-class detection thresholds: LEO 0.600, MEO 0.800, GEO 0.200, IGSO 0.100 (a class without its own gate uses the default above).
- Inference: CPU-only; the bundle ships the network weights, the normaliser, and these parameters together, so loading it never needs the training stack.
Training data
Trained on the maneuver-detect labelled dataset v0.3.0
(astro-tools/maneuver-detect), versioned in lockstep
with this checkpoint. The dataset is distributed recipe-first (operator labels + a pinned
reconstruction recipe + a content-hash manifest; the raw Space-Track element history is never
redistributed) and partitioned by the frozen, leak-free temporal-holdout splits โ novel satellites
scored in novel eras.
Evaluation
Held-out test split โ recall/precision at 1 false alarm(s)/satellite-year over the above-floor population (95% CI). Operating pt is the per-class confidence cut admitted within that false-alarm budget (in the detector's calibrated confidence units). Type acc is the share of above-floor true positives whose maneuver type is correct.
| Class | Recall | Precision | Operating pt | Above-floor labels | Type acc |
|---|---|---|---|---|---|
| LEO | 0.44 | 0.91 | 0.98 | 71 | 0.32 |
| MEO | 0.29 | 0.17 | 0.87 | 14 | โ |
| GEO | 0.00 | 0.00 | 1.00 | 71 | โ |
| IGSO | 0.00 | 0.00 | 0.63 | 3 | โ |
| HEO | โ | โ | โ | 0 | โ |
This detector emits calibrated confidence: the raw score is mapped through a temperature (T = 1.000) fit on the val split only, so a confidence of p means about a fraction p of detections at that confidence are real. A split-conformal predictor (marginal coverage 90%) accompanies it for prediction sets. Per-orbit-class expected calibration error (ECE) of the calibrated confidence:
| Class | ECE |
|---|---|
| LEO | 0.512 |
| MEO | 0.673 |
| GEO | 0.274 |
| IGSO | 0.292 |
| HEO | 0.000 |
The per-class reliability diagrams and the calibrated per-class operating points are published in the benchmark documentation.
Best validation-split above-floor recall during training: 0.459.
The benchmark scores precision/recall at a fixed false-alarm rate per orbit class over the above-floor population, with per-class type confusion, via the deterministic scorer. Performance is sharply data-quality-stratified: well-tracked modern satellites reach literature-level recall, while noisy historical series are bounded by the TLE detectability floor.
Intended use and limitations
- Use: post-hoc detection of orbital maneuvers from public TLE history for space-situational- awareness research and as a reproducible benchmark baseline.
- Not a maneuver predictor (it detects maneuvers that already happened), not real-time, and not an orbit-determination engine.
- Detectability floor: maneuvers below the per-object TLE detectability floor are not reported; recall on noisy historical series is fundamentally limited by TLE data quality, not the model.
- MEO/GEO labels are epoch-only (no ฮv), so the ฮv estimate is most meaningful on the ฮv-labelled LEO core.
Provenance
- Dataset version (lockstep): v0.3.0
- Parameters: 9,486,337
| field | value |
|---|---|
best_val_recall |
0.4591 |
dataset_version |
0.3.0 |
loss |
bce |
optimizer |
adamw |
scheduler |
warmup_cosine |
seed |
0 |
License
Model weights: MIT. The dataset and authored artifacts are CC-BY-4.0; the raw Space-Track
element history is never redistributed. See the
repository for the full source terms, and
CITATION.cff to cite.