--- license: cc-by-4.0 task_categories: - audio-classification - object-detection tags: - drone-detection - counter-uas - acoustic-array - cue-to-track - autonomous-drill pretty_name: "nightjar 2026-08-11 — first autonomous hover drill: the loop closes in 18 s" --- # nightjar 2026-08-11 — the first autonomous cue drill (hover station) A drone hovered at a fixed station above the WP beacon (~daylight, post-rain) while the rig ran the SELF-JUDGING look-away drill: point away → re-arm → the acoustic chain must re-find the drone → YOLO-vouched lock, scored against a self-bootstrapped truth pose. No operator in the loop: truth was acquired by ear (cue chain → slew → YOLO lock), the station gate froze at the WP bearing, and every trial was scored automatically. ## ★ Headline: the clean run closes the loop in 18–22 s at 0.2° The final drill run (`drill_20260811_151955`, the only one with a SINGLE drill process — see the incident below) is the honest measurement: | trial | total time (incl. look-away + slew) | lock error | zoom at end | |---|---|---|---| | T1 | 22.2 s | **0.24°** | 29.0 mm | | T2 | 18.2 s | **0.15°** | 25.5 mm | Chain legs in the clean run: **cue ≈ 0 s** (drone continuously audible; a cue is always pending at re-arm), **detection ≈ 0 s** (the slew lands with the drone already in frame), **vouch ≈ 0 s**, then settle + zoom climb. Success bar was 5 consecutive locks <15 s / <2° / ≥30 mm — not reached only because the session ended after two trials; both trials beat the error bar by 10×, and zoom was still climbing when the run was stopped. ## The acoustic side, 12 min of hover ``` 172 cue candidates (14.4/min), az 139.6–144.8 (median 142.5, spread ±2.6°) presence median 19.9 dB, max 25.0 · chirp_rejects 10 (guard off, no pinger) ``` **Cue bias +5.8° — consistent, and NOT an error.** The offset is anchored on the FAR beacon (JBL, parallax→0, matches drone-at-range geometry); the drone hovered above the NEAR WP beacon, so array↔camera parallax (~3 m baseline) shows up as a stable ~+5.8°. Containment absorbed it: the slew still put the drone in frame every time (det ≈ 0 s). At operational range this bias vanishes by construction. ## ⚠ THE INCIDENT: three concurrent drill processes (runs 151000 / 151031 / 151200) Retried ssh launches all fired, stacking **three drills onto one mount**. They fought over arm/disarm and pointing: interleaved trials, contradictory results for the same trial number, "truth" yanked +14.4° while the drone hovered motionless, lock errors of 8–9.6°, vouch times of 22–48 s. **Do not use those three runs for latency or accuracy conclusions** — every slow number there is mount contention, not the tracker. (The clean run's vouch ≈ 0 s refutes the "confirmation-confidence is the choke" hypothesis those runs suggested; a `yolo_confirm_conf` change made on that basis was reverted the same day.) Fixes shipped immediately: `cue_drill.py` now takes an exclusive flock (a second instance refuses to start), and `drill_start.sh` / `drill_stop.sh` on-rig launchers keep dangerous patterns off the ssh command line (a raw pkill in an ssh line self-matched and killed its own session twice today). Double-start refusal verified live. ## Contents ``` audio/uma16_*.wav UMA-16, 16 ch, 48 kHz, 5-min splits (12 min hover) audio/cue_log.jsonl 172 candidates with az/presence/line_hz video_segments.tar 1080p native + substream, 60 s MPEG-TS blackbox/state.jsonl tracker FSM ~3 Hz blackbox/frames.tar 8,753 substream stills drill_20260811_151000/ trials.csv + events.jsonl ⚠ 3-process contention drill_20260811_151031/ trials.csv + events.jsonl ⚠ 3-process contention drill_20260811_151200/ trials.csv + events.jsonl ⚠ 3-process contention drill_20260811_151955/ trials.csv + events.jsonl ✅ CLEAN single instance ``` Registration in force: UMA `az_offset 323.30 / invert true` (far-beacon anchored, verified by pointing to 0.02° the previous evening). DJI FlightRecord not yet attached — add under `dji/` when exported. UMA-16 ch9 (0-based) is dead; exclude it.