Automatic Fatigue Test Control System (AFTCS)
Bibliographic record
Abstract
Bell Helicopter's next-generation Automatic Fatigue Test Control System (AFTCS) is presented. Fatigue testing places a helicopter part or specimen under repeated, controlled cyclic loading to determine if and when it will fail. A National Instruments PXIe embedded processor and LabVIEW software are used to control up to 48 linear/rotary hydraulic actuators in real-time. The actuators apply structural loads that are sensed by up to 256 strain gauges on the helicopter specimen. The structure and instrumentation respond to prescribed cyclic loads that range in frequency from 0.5 to 30 Hz, with a minimum resolution of 0.1 Hz. The fatigue test controller design is based on the well-known Linear-Quadratic-Gaussian control (LQG) methodology. Its feedback and filter gains are computed using a state-space model of the specimen identified separately. The controller computes any necessary changes in the actuator motions (at every time sample), maintaining acceptable margin between the measured and desired strain gauge responses. The system is demonstrated on a Bell Helicopter 429 tail rotor blade.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.025 | 0.007 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".