GreenVLA-5b-stride-4-R1-fractal is the R1 (embodiment-adapted) checkpoint of the
Green-VLA family, fine-tuned on the
Fractal dataset for the Google Robot.
Starting from the
GreenVLA-5b-base-stride-4 pretrained checkpoint, this model was adapted via supervised fine-tuning (R1 stage) to the Fractal embodiment, achieving strong manipulation performance on the SimplerEnv benchmark.
1git clone https://github.com/greenvla/GreenVLA.git
2cd GreenVLA
3uv sync # or: pip install -e .
1import numpy as np
2import torch
3from lerobot.common.policies.factory import load_pretrained_policy
4from lerobot.common.utils.torch_observation import (
5 move_dict_to_batch_for_inference,
6 torch_preprocess_dict_inference,
7)
8
9# 1. Load policy and transforms.
10policy, input_transforms, output_transforms = load_pretrained_policy(
11 "SberRoboticsCenter/GreenVLA-5b-stride-4-R1-fractal",
12 data_config_name="fractal",
13)
14policy.to("cuda").eval()
15
16# 2. Build an observation (replace with real sensor data).
17raw_obs = {
18 "observation/state": np.random.rand(8), # x, y, z, rx, ry, rz, rw, gripper
19 "observation/image": np.random.randint(256, size=(448, 448, 3), dtype=np.uint8),
20 "prompt": "move the coke can to the left of the table",
21}
22
23# 3. Transform, preprocess, and batch.
24obs = input_transforms(raw_obs)
25obs = torch_preprocess_dict_inference(obs)
26batch = move_dict_to_batch_for_inference(obs, device="cuda")
27
28# 4. Predict actions and post-process.
29with torch.inference_mode():
30 raw_actions = policy.select_action(batch).cpu().numpy()
31
32actions = output_transforms(
33 {"actions": raw_actions, "state": batch["state"].cpu().numpy()}
34)["actions"]
35# actions shape: (action_horizon, 7) — [x, y, z, roll, pitch, yaw, gripper]
See
examples/example_inference_fractal.py for the full runnable script with argument parsing.
1@misc{apanasevich2026greenvlastagedvisionlanguageactionmodel,
2 title = {Green-VLA: Staged Vision-Language-Action Model for Generalist Robots},
3 author = {I. Apanasevich and M. Artemyev and R. Babakyan and P. Fedotova and
4 D. Grankin and E. Kupryashin and A. Misailidi and D. Nerus and
5 A. Nutalapati and G. Sidorov and I. Efremov and M. Gerasyov and
6 D. Pikurov and Y. Senchenko and S. Davidenko and D. Kulikov and
7 M. Sultankin and K. Askarbek and O. Shamanin and D. Statovoy and
8 E. Zalyaev and I. Zorin and A. Letkin and E. Rusakov and
9 A. Silchenko and V. Vorobyov and S. Sobolnikov and A. Postnikov},
10 year = {2026},
11 eprint = {2602.00919},
12 archivePrefix = {arXiv},
13 primaryClass = {cs.RO},
14 url = {https://arxiv.org/abs/2602.00919},
15}