rskill-diffusion-pusht

OpenRAL rSkill — Diffusion Policy (Chi et al., 2023) trained on the PushT 2-D pushing benchmark, packaged for OpenRAL.

This package wraps lerobot/diffusion_pusht with a rskill.yaml manifest. It does not copy model weights.

Upstream model

Field	Value
Source repo	lerobot/diffusion_pusht
Paper	arxiv:2303.04137 — Diffusion Policy: Visuomotor Policy Learning via Action Diffusion (Chi et al., 2023)
License	Apache-2.0
Parameters	~263 M (1-D U-Net)
Action chunk	8 (within horizon 16)
Denoising	100 DDPM steps per chunk
Benchmark	PushT (gym_pusht, pymunk 2-D rigid-body)

Per-chunk inference is dominated by the 100-step denoising loop; cached pops are essentially free, so this is the extreme test of the queue-drain contract in ChunkedExecutor.

Supported robots

Robot	Embodiment tag	Status	Notes
PushT 2-D pseudo-robot (gym_pusht/PushT-v0)	pusht, lerobot	✓ sim	2-D end-effector pushing a T block on a 512 × 512 px canvas

Sensors required

Key	Type	Resolution	Format
observation.image	RGB camera	96 × 96	float32

PushT predates the multi-cam observation.images.cameraN convention and exposes the raw key observation.image.

Manifest summary

Field	Value
name	OpenRAL/rskill-diffusion-pusht
version	0.1.0
license	apache-2.0
role	s1
embodiment_tags	pusht, lerobot
runtime / quantization.dtype	pytorch / fp32
weights_uri	hf://lerobot/diffusion_pusht
latency_budget.per_chunk_ms	1 250 ms (warm full-chunk ≈ 1 756 ms on RTX 4070 Laptop, dominated by DDPM)
latency_budget.warmup_ms	10 000 ms
latency_budget.load_ms	30 000 ms
commercial_use_allowed	true

Full schema: openral_core.RSkillManifest — python/core/src/openral_core/schemas.py.

Reproduction

git clone https://github.com/OpenRAL/openral && cd OpenRAL
just bootstrap && uv sync --all-packages --group sim

# End-to-end via the canonical SimEnvironment config (CPU is enough):
just sim-diffusion-pusht
# which runs:
#     openral sim run --config scenes/benchmarks/diffusion_pusht.yaml --save-video

# Sim test (gym_pusht + pymunk):
uv run pytest tests/sim/test_pusht_2d_diffusion_pusht.py -v -m sim

License

This rSkill package (rskill.yaml, README.md) is Apache-2.0 to match the upstream weights. Commercial use is allowed (commercial_use_allowed: true).

See also

• robots/pusht_2d/README.md — RobotDescription manifest.
• scenes/benchmarks/diffusion_pusht.yaml — paired SimEnvironment config.
• docs/reference/vla_compatibility.md — VLA × Robot × Sim matrix.