Tracking without detection
Detectors blink. A lock has to survive the gap between two sightings without inventing a target that isn’t there.
Real detectors do not fire every frame. Underwater, against murk and caustics, they drop out for stretches — we counted 71 real gaps in one run. If the controller only acts when the detector fires, the vehicle stutters and loses its target.
So you build a lock ladder: a small state machine that coasts a target through detection gaps, sized against the real distribution of gaps rather than a guessed timeout. The rungs are honest about confidence — a rung that names the wrong prop confidently is worse than one that reports LOST, because LOST is honest.
The failure modes are asymmetric: a missed re-acquisition costs a second; a false one costs the run.
That asymmetry sets the gates. You would rather lose the target and know it than weld two objects into one identity and have every downstream consumer believe the target teleported. Robustness here is not a bigger model — it is refusing to lie during the gap.