Doctoral Research · Space Robotics Inspection with a Free-Flying Space Manipulator
A Doctoral Research Journal Aerospace Engineering

CHAIN_13 — live reach-corridor sweep (below rs 0.40)

Criteria: tasks/chain13_corridor_sweep_criteria.md. Metrics = run_mission.analyze. FLOOR = coverage < 0.99 OR not completed (rs below the usable floor — do not adopt).

run coverage completed pe_p99 abs derated [s] derate frac t_complete [s] ze_p99 pe_med verdict
rs 0.55 (incumbent) 0.9981 True 0.1651 689.3 0.644 1070.8 0.0549 0.0712 gate-pass
rs 0.45 0.9981 True 0.1644 619.9 0.766 809.2 0.0463 0.0922 gate-pass
rs 0.40 0.9978 True 0.1586 485.8 0.637 762.6 0.0495 0.1018 gate-pass
rs 0.35 0.9965 True 0.1603 358.0 0.478 749.7 0.0523 0.1217 gate-pass
rs 0.3 0.9944 True 0.1639 0.0 0.000 694.9 0.0562 0.1313 gate-pass
rs 0.25 0.9942 True 0.1700 0.0 0.000 691.5 0.0570 0.1282 gate-pass
rs 0.2 0.9953 True 0.1803 638.1 0.790 807.4 0.0513 0.1506 gate-pass

Adoption rule (criteria): smallest rs holding coverage>=0.99 + completed + pe_p99<0.2 that improves abs-derated-time/pe_p99 vs incumbent, then ±2% probes. rs 0.40 stays the winner unless a smaller rs dominates it AND passes ±2%.

rs 0.30 coverage-under-noise pre-check (Jun 14)

The only thing favoring rs 0.30 over the pe_p99-optimum rs 0.40 was its zero-derate “singularity-free” valley — which would have required a registered objective amendment to adopt. Before amending, we probed whether the valley survives the fragility campaign’s worst-case (hi) noise. Tool: validation/corridor_noise_precheck.py (radius_scale at LOAD time + UncertaintyModel). Seed 0, full helix.

cell coverage derate pe_p99 verdict
rs 0.30 nominal (no noise) 0.9944 0.000 0.1639 reference
rs 0.30 camera-hi (pos 0.10 m, ang 5°) 1.0000 0.000 0.1639 valley holds
rs 0.30 state-hi (pos/vel 0.05) 0.9955 0.596 0.1602 valley BROKEN

Finding. Coverage held in both cells (>=0.99). The singularity-free property did not: state-estimation noise drove derate 0.000 -> 0.596. Mechanism: the zero-derate sat ~2 mm above the 0.025 floor (sj_min ~0.0269); camera-pose noise perturbs FOV marking only (arm conditioning untouched -> derate flat), but state noise (std 0.05 m ~= 25x the margin) perturbs the commanded joint trajectory across the singular wall. The valley is speed-robust (prior ±2% probes flat) but state-noise-fragile.

Decision. Registered rule = both coverage>=0.99 AND derate stays 0 -> rs 0.30; either breaks -> rs 0.40. Derate broke -> adopt rs 0.40, no objective amendment (rs 0.40 = pe_p99 optimum + registered-rule winner; rs 0.30 never dominated and its sole differentiator is a noise-free artifact). §3b re-pin = radius_scale 0.55 -> 0.40.

Campaign note (preview, not a blocker): derate is itself highly state-noise-sensitive (0.000 -> 0.596 from one source) — expect conditioning to be among the most-moved metrics in the 46-run study at any standoff.