`handover_place@v1` — Handover-and-place under takt pressure

A black-box presenter hands a part into a shared workspace; the ego arm must place and seat it within a downstream tolerance at cycle time, without a full re-grasp it cannot afford. The partner binds only through the hand-off initial condition — the grasp-pose error the ego must correct within its wrist-correction and re-grasp budgets. The binding is a tolerance phenomenon, so a pure-Python kinematic resolver captures it and the task runs on any host.

Tier 2 — admitted cooperation tasks · Status: ADMITTED · Suite: CHAMBER-Bench v1.0 (adr/ADR-027-chamber-bench-v1-protocol.md)

Spaces

Action space. Kinematic decision surface: the ego corrects the presented grasp-pose error by wrist correction or a budgeted set-down-and-regrasp; the presenter binds only through the hand-off initial condition.
Observation. Kinematic pose/timing state (presented part pose + grasp-pose error, takt and regrasp budgets).
Simulator backend. pure_python · Agents. 2

Stress channel

Seating contact force from the kinematic resolver, gated by seating_force_limit_n

Axis validity

Per-cell status under the validity matrix (adr/ADR-027-chamber-bench-v1-protocol.md):

AS	OM	CR	CM	PF	SA
`untested`	`untested`	`untested`	`untested`	`untested`	`untested`

Industrial analogue

Asynchronous part transfer between a feeder robot and a placing robot in machine tending: the upstream robot presents a part at takt, and the downstream robot must seat it in a fixture window without breaking cycle time for a re-grasp.

Evidence

How to run one episode

import chamber.tasks

env = chamber.tasks.make("handover_place")
obs, info = env.reset(seed=0)
# Pure Python — runs on any host.

Notes

ADMITTED by the committed admission report (ADR-027 §Admission protocol; tag prereg-admission-handover-place-2026-07-05), which wraps — never re-runs (I8) — the measured Gate-0 verdict COUPLING_VALID + SOLVABLE (PR #263, tagged Rev-2 prereg prereg-handover-place-gate0-rev2-2026-06-26, blob b26cfba74a2f1bb9ac295810e4846fe23742ff1b): A1 from Limb 1 (band minima matched IQM/CI-lower 1.000 >= tau_solv 0.90), A3 from Limb 2 restricted to the coupling-valid family (min gap CI-lower 32.5 pp >= 20 pp), plus the one fresh A2 presenter-ablated cell (0/100 — with no presenter the part never enters the ego's workspace). Canonical benchmark cells are pinned to the measured coupling-valid region: the clearance-0.2 family with 30°/45° grasp-pose mismatch across the realistic takt band — 22 of 216 measured cells, valid takt windows at clearance 0.2 of [0.3, 1.5] s (fast profile) and [0.3, 2.0] s (slow profile) per GATE_VERDICT_REPORT_2026-06-26.md. Cells outside that region are not leaderboard cells.

handover_place@v1 — Handover-and-place under takt pressure