r16_deploy/README.md

r16_deploy (H) — deploy candidate: smoothest walker in the r16 series

Trained locally (RTX 5090), report-16. First arm designed for the ROBOT rather than a hypothesis.

Task	ETHRC-humanoidv1-walk-r16-deploy-psu-v0
Branch	test/SjohnU_remodel_actuators @ b0ceaa8
Checkpoint	model_9999.pt (10,000 iters, completed)
Envs / seed	4096 / 42
Actions	26 @ 50 Hz, action_scale 0.25
Base	u4_walk_crouch_real + r16 shared (25% standing, track 1.5→2.2)
Changes	~65 ms latency + HEJ90 legs 200/10 + upright price (−10) + spawn-tilt DR + action_rate −0.3 + feet_clearance removed

It is the least jittery policy in the series — by design

Measured with scripts/rsl_rl/measure_gait.py (1000 steps × 64 envs, spawning upright). Jitter — not velocity — is what predicts real-robot chattering; velocity and cadence cannot see it.

@ 0.5 cmd	fwd vel	steps/s	leg vel RMS	action rate	sign-flips/s	lean
r16_upright (C) — fastest, DO NOT DEPLOY	0.406	3.37	1.697	0.126	12.5	0.7°
r16_latency_g200 — prev. smoothest	0.342	3.48	1.170	0.093	10.6	10.8°
r16_deploy (H)	0.369	3.48	1.023	0.074	10.4	3.0°

At the 0.8 command H does 0.588 m/s with ~16.5 cm strides, still smoother (RMS 1.206) than C was at 0.5. Stride comes from commanding velocity, not reward shaping (the gait clock pins cadence ~3.5 steps/s, so step_len = v/cadence).

Why this and not the faster r16_upright (C)

C wins every sim metric (0.406 m/s, 0.7° lean) but is the jitteriest arm (leg vel RMS 1.697, +40% vs H) because it trained at zero latency — it learned 50 Hz twitch-correction. On hardware those corrections arrive ~67 ms late and become oscillation, so C's sim smoothness UNDERSTATES its real jitter. H trains with the measured ~65 ms delay, which is why it is smooth AND deploy-faithful. Latency is load-bearing, not a tax.

action_rate −0.3 did NOT strangle H (episode length 973/1000). The final_phys sibling that suicided was killed by an over-large PHYSICAL-smoothing block (joint_acc ×10, soft_landing ×100), not by the action_rate weight.

Known gaps (fold in before final deploy)

1. Placeholder ankle 2.0/0.15, not the real-measured 8/1.5. The r16_h_ankle Sky arm tests whether the real ankle can walk at all — the last deploy-critical unknown.
2. Velocity-curriculum bug caps forward command at 0.5 (lin_vel_cmd_levels clamps to limit_ranges (-1.0, 0.5)). The r16_h_cmd arm fixes it to (-0.2, 1.2). H's 0.588 at a 0.8 command is extrapolation past its training ceiling.
3. No foot-height reward — feet_clearance was removed (documented bug) and not replaced, so feet_air_time is the only swing incentive. The final-* arms add feet_swing_height_dense.

Files

• policy.pt, policy.onnx — exported via scripts/rsl_rl/play_export.py
• deploy.yaml — gains (legs motor-space ~189.6/9.64 = 200/10 sim), obs/action layout, 50 Hz
• model_9999.pt — raw rsl-rl checkpoint