15. Literature-sourced arms — standing

Tag: lit-arms · idea #15 · index

The arXiv radar (VLA/robot learning, flow matching, action tokenization, data curation) feeds this list; every borrowed idea cites its source in the pre-registration; every “novel” idea gets a search first. Local canon: π0, π0.5, SmolVLA, FAST (arXiv:2501.09747).

• π0.5 canon deep-read DONE (2026-08-07, post) — π0.5 (arXiv:2504.16054) + KI (arXiv:2505.23705), read against the live stage-2/Molmo2 question. Findings banked into #4 (two named attachment arms), #5 (FAST-vs-naive ablation), #6 (Implicit-HL replication + self-subgoal rung-(a) probe), #16 (Fig. 8 external anchor). Convention flag: π0.5’s τ=1 is DATA; ours is NOISE.

• IVRA (arXiv:2601.16207, lit slice 2026-08-06 16:2xZ) — training-free, inference-side: VLAs flatten patches to 1D and lose 2D spatial cues; IVRA injects vision-encoder patch-affinity signals into ONE LM layer (“where instance-level features reside”), no retraining, +4.2% on VIMA low-data / consistent LIBERO gains across LLaRA/OpenVLA/FLOWER. Fits #11’s diagnosis exactly (acuity probe: position info sharpest at tower output, degraded through LM layers). Our analogue: bias trunk attention over soft tokens with tower-output affinities at eval — rung (a), zero training, panel first_mae is the readout. Cheapest falsification: single-layer injection on the flow teacher, panel-v2 first_mae vs banked 2.0720 ctrl. Worth a probe if arm A’s img280 read leaves grounding headroom on the table (interacts: more tokens vs better-used tokens are the same front, opposite ends). Papers-page re-read 2026-08-07 (page): mechanism is token-feature mixing (affinity-weighted pooling + convex blend λ≈0.2–0.3), not attention editing; best at layer 20/32 (~62% depth), LM-input injection catastrophic; banked “LIBERO gains across LLaRA/OpenVLA/FLOWER” corrected — LLaRA is never on LIBERO (its results are VIMA low-data +4.2 and a small real study).

• Lit slice 2026-08-07 ~07:5xZ (session slice, two banked): (a) TapSampling (arXiv:2605.25547) — a FOURTH selection-rung flavor for #19: inference-time sampling with a TASK-PROGRESS verifier (learned progress-understanding score filters sampled action candidates per step). Joins MG-Select (verifier-free KL) / VLA-ATTC (trained pairwise critic) / CoVer (contrastive instruction-alignment verifier) in the banked flavor list — all wait behind the oracle best-of-10 ceiling read (idea19-selection-ceiling-read-script): if the ceiling is small, every one of these is dead on our panel; no selector gets built before that number exists. (b) AR-VLA (arXiv:2603.10126, RSS 2026) — a standalone AR action EXPERT generating actions as a continuous causal sequence over refreshable vision-language prefixes, with its own persistent history — a third attachment topology beside our F (frozen-trunk flow expert) and K (KI-joint): the expert keeps cross-observation memory instead of resetting per chunk. Not actionable while the #4 seam screen is the live question (its F/K verdict comes first); banked to #17 as the history-aware-expert direction if the attach screen leaves headroom. Also seen: “representation anchoring” (arXiv:2607.13429, frozen-copy distillation to keep OOD generalization during finetuning) — context for the K named-cost branch’s repair space, recorded here only; AEGIS stays the single pre-registered escalation (frozen decision rule untouched). Papers-page re-read 2026-08-07 (page) — both sharpened: AR-VLA is NOT a third trunk topology — it freezes the VLM + stop-grads explicitly (“AR gradients degrade the VLM like flow gradients”), independent outside-the-flow-family support for the K premise; its memory number is history length 1→20 = +25 pts (36.5→61.5), with the tax that no-masking training collapses to 0% and OOD actions feed back through the cache. Anchor-Align (2607.13429) is half-banked — a co-equal language-action alignment loss (6-way direction words through the frozen LM head) drives its pink-mug result; on its benchmark the leash beats BOTH a Co-training+KI baseline (71.9 vs 43.8) and full-freeze (43.1); cheap probe to steal: VQA-retention on the Molmo2 trunk before/after stage-2 (naive BC loses 94% GQA in 10k steps, anchoring keeps ~70%).

• Lit slice 2026-08-07 ~08:2xZ (session slice, two banked): (a) Look Before You Leap (arXiv:2607.03751) — a FIFTH selection-rung flavor for #19: MCTS explores a FROZEN VLA’s output distribution offline, then distills the search into a Q-value action evaluator used at test time (trained-critic family beside VLA-ATTC, but the critic’s labels come from tree search over the policy’s own distribution, no human/reward labels). Same gate as the other four: waits behind the best-of-10 ceiling number — the script for that is now landed, so the flavor list has its adjudicator ready at the ~08-08 endpoint dump. (b) DVAC (arXiv:2606.03847) — training-free, orthogonal to selection: variance of the clean-action estimate over the FINAL DENOISING STEPS of a flow/diffusion policy decides when to replan (execute the stable low-variance prefix, replan before high-variance tails); π0.5-based flow policies, LIBERO 94.75→98.00 with 43% fewer replans. Banked to #1 as the inference-time cousin of our dispersion machinery — our panel is offline chunk-MAE (replan timing is invisible to it), so this is a ROLLOUT-phase lever for the rig/sim stage; note the ceiling read’s dispersion-vs-gain quartiles are exactly the offline precursor (if oracle gain concentrates in high-dispersion frames, both selection and DVAC-style commit-gating draw from the same signal).

• Lit slice 2026-08-10 lit-radar-0822 — THE FINAL SLICE BEFORE THE OWNER PAUSE (owner steering 2026-08-10 00:23Z, “Can we pause the lit slices for now” — the slice was mid-flight when the message landed and was completed and landed quietly; no 0823 queued; the standing ~20–30 min allocation is suspended until the owner re-enables it). Four pages: Ambient Diffusion Policy (flow-time band-mask lever, ports to rectified flow in σ-space, needs a user-supplied partition → composes with QoQ; +33% hook was tower height), What Curation Metrics Do (detection/policy decoupling 0.804→13.3%, episode-length confound

  • truncation control, one-cell caveat), Auditing Curation Metrics (action-only scorers chance-level on wrong-action defects, entropy /ensemble actively inverted, “state” rescue = object pose not proprio — ablation never run), PhAIL (time-to-success CDFs + macro-KS + clustered bootstrap; human anchor carries zero statistical power; 22 pp spatial-nuisance warning). Fed #9 (band-mask lever + scorer design constraints) and #16 (rig-day statistical protocol). Unexecuted 0822 spares + the 0823 sweep-planning note remain recorded in the closed queue item (lit-radar-0822, queue.json) for whenever the pause lifts.