Does MolmoAct2 run on SO-101?

Capabilities

Caveats

• The MolmoAct2-SO100_101 weights expect the pre-LeRobot-0.5.0 joint calibration convention: lerobot/MolmoAct2-SO100_101-LeRobot includes the frame correction, but self-converted or fine-tuned checkpoints must set joint_signs/joint_offsets or the arm may move in the wrong direction.
• LeRobot's rollout example is written for so100_follower; SO-101 coverage rests on the official model card's SO-100/101 scope.

Evidence 2 sources; the cell shows the highest tier

1. T1 · upstream documentedmodel-cardsource 2026-05-23verified 2026-10-24 (1d ago)

   Ai2's official MolmoAct2-SO100_101 model card: fine-tuned on an SO-100/101 data mixture, intended for SO-100/101 inference and further fine-tuning.

   “This checkpoint is fine-tuned on the SO-100/101 mixture with absolute joint-pose control and annotated language instructions. It is intended for both further fine-tuning and SO-100/101 policy inference.”

   https://huggingface.co/allenai/MolmoAct2-SO100_101/blob/152569fe57914d97be91055800035f54e250d009/README.md
2. T1 · upstream documentedofficial-docssource 2026-08-03verified 2026-10-24 (1d ago)lerobot 0.6.1

   LeRobot v0.6.1 MolmoAct2 guide warns that the SO-100/101 checkpoint uses the pre-0.5.0 joint calibration convention; the converted LeRobot checkpoint includes the frame correction, self-converted/fine-tuned ones need joint_signs/joint_offsets.

   “The MolmoAct2-SO100_101 checkpoint was trained on data that uses a different joint calibration convention than LeRobot >= 0.5.0. Without a frame correction, the arm may move in the wrong direction.”

   https://github.com/huggingface/lerobot/blob/v0.6.1/docs/source/molmoact2.mdx

MolmoAct2 inference speed by hardware robot-independent · inference cost only