lingbot-va-mot-posttrain-libero-goal-gradaccum43

Full-parameter post-train of lingbot-va-mot on the LIBERO-Goal benchmark (10 tasks, original prompts). Base architecture is the Mixture-of-Transformers (MoT) video-action model from joliachen/lingbot-va (model_mot.py).

Training config

base checkpoint	checkpoints/lingbot-va-mot
dataset	LIBERO-Goal (data/libero_goal_lerobot)
freeze_backbone	False — full-parameter fine-tune, all 10.0B params (30-layer video stream + action stream + embedders/heads)
steps	4000
learning rate	1e-5
world size	2 GPUs
gradient_accumulation_steps	43 (effective batch = 2 × 43 = 86)
attn_window	72
frame_chunk_size	4
guidance_scale / action_guidance_scale	5.0 / 1.0
num_inference_steps / action_num_inference_steps	25 / 50
snr_shift / action_snr_shift	5.0 / 0.05
action representation	30-dim padded vector; native 7-dim LIBERO OSC action (xyz + euler + gripper) in slots 0–6, rest zero-padded
observation cameras	agentview_rgb, eye_in_hand_rgb

Architecture note: action stream width

This checkpoint (and its lingbot-va-mot base) uses a no-bottleneck MoT design: the action stream runs at the full video-stream width d_v = 3072 end-to-end (action_embedder: Linear(30 → 3072), action_proj_out: Linear(3072 → 30), and every per-block action module — action_attn1/2, action_ffn, action_norm2, action_scale_shift_table — is shape-identical to its video-stream counterpart). This differs from the lingbot-va paper, which describes the action stream operating through a narrower 768-dim bottleneck (30 → 768 → … → 768 → 30) rather than the full 3072-dim width used here. See lingbot-va-mot's model card for how these action-stream weights were initialized before this fine-tune.

LIBERO-Goal closed-loop evaluation (checkpoint step 4000)

10 episodes/task, closed-loop rollout in the LIBERO-Goal env:

Task	Success
open the middle drawer of the cabinet	9/10
put the bowl on the stove	10/10
put the wine bottle on top of the cabinet	9/10
open the top drawer and put the bowl inside	10/10
put the bowl on top of the cabinet	8/10
push the plate to the front of the stove	10/10
put the cream cheese in the bowl	10/10
turn on the stove	10/10
put the bowl on the plate	10/10
put the wine bottle on the rack	10/10
Total	96/100 (96.0%)

Repo contents

Only transformer/ (the fine-tuned weights) is included here. The original checkpoint directory also symlinks text_encoder/ (google/umt5-xxl), tokenizer/, and vae/ (Wan2.1 AutoencoderKLWan) from the shared base checkpoint — those are unchanged stock components and are not duplicated in this repo. Load them from ZhuoranChen/lingbot-va-mot or the public Wan2.1 release when using this checkpoint standalone.