imp_blend_b — cocarry_partners@v1

Set. cocarry_partners@v1 (task cocarry@v1) · Stratum. scripted · Split. public · Role. partner_arm

Identity. partner_id 6883ea1ebef2f0d3 · parameter digest b1a0fa0aa3ee2d96af0073a70ed040fa6d90efffaeb3a956396cd5704912ddb2 · weights_uri member://cocarry_impedance/b1a0fa0aa3ee2d96af0073a70ed040fa6d90efffaeb3a956396cd5704912ddb2

What this partner does

A deterministic end-effector-space PI impedance controller for one co-carry arm (ADR-026 §Decision 1): it drives its bar-end toward the cooperative goal along a straight Cartesian path through a damped pseudo-inverse Jacobian, sharing the bar load compliantly with the ego arm. kp/ki set the Cartesian PI gains, step_max the per-step command clip (response speed), damping the pseudo-inverse regularisation, and lag_steps a bounded transport delay (a sluggish-but-competent member: delayed but convergent tracking).

Construction provenance

Built from registry class cocarry_impedance (PartnerSpec(seed=0, checkpoint_step=None)). Public member: the exact values below were drawn from the committed box under the maintainer-held derivation seed and are committed next to their digest.

parameter	committed box	value
damping	[0.02, 0.08]	0.0232
ki	[0.4, 0.8]	0.6453
kp	[1.3, 3.8]	1.6573
lag_steps	[0, 3] (int)	1
step_max	[0.02, 0.04]	0.0398

Behavioural fingerprint

Committed probe suite: seeds [7000, 7001, 7002, 7003] x 5 episodes against the task's reference ego (archive: spikes/results/partner-fingerprints/cocarry_partners-v1/imp_blend_b/, an ADR-028 v3 bundle). Summary statistics of the member's action distribution and the dyad's stress channel — enough to tell members apart without policy access (ADR-018/I3).

statistic	value
action_abs_mean	0.3774
action_abs_p90	1
action_std	0.486
n_episodes	20
stress_max	112.2
stress_mean	87.12
stress_p50	88.22
stress_p90	101.8
success_rate	1

Competence floor. floor probe fingerprint — success 1 vs committed floor 0.75 → PASS