ACT: Action Chunking with Transformers
SoftwareAction-chunk imitation-learning implementation with paired-arm simulation tasks and separate ALOHA hardware integration. [1] [2] [3] [4] [5] [6]
Installation & first result →Official websiteGetting started
- Source rights
- Named licenses are documented by part. Review licenses
- Unknowns
- operating system not fully established. Review gaps
Source researched · Not tested by us
Sources checked · Research details
Overview
ACT implements action-chunk imitation learning with Transfer Cube and Bimanual Insertion simulation tasks. Its real-robot route additionally requires the separate ALOHA project. This entry concerns policy and simulation code; it does not establish another open hardware design or a reproduced manipulation result. [1] [3]
Is this for you?
- Known limitations
- Dataset/checkpoint normalization and14-dimensional paired-arm state must match.
- Real-robot route requires separate ALOHA installation; no hardware operation or success rate reproduced.
Editorial assessment of cited source; no runtime or hardware test.
What you need
- Dependencies
- README Python3.8.10,MuJoCo2.3.7,dm_control1.0.14 and editable act/detr install
- PyTorch/torchvision and other packages mostly unpinned; inspected training/evaluation uses CUDA
- Compute for the workload
- Selected training/evaluation source invokes CUDA; no independently validated CPU-only path or measured minimum GPU/RAM budget.
Upstream documented requirement/configuration only, not independently tested installation or compatibility.
Installation & first result
Open the upstream getting-started guide [1] [2] [3] [4] [5] [6]
- Inspect sim_transfer_cube_scripted and replace DATA_DIR in constants.py.
- Follow the pinned environment/data-recording route, then keep dataset_stats.pkl with the trained checkpoint.
Editorial assessment of cited source; no runtime or hardware test.
- Installation
Conda Python 3.8.10; README pins mujoco 2.3.7 and dm_control 1.0.14, installs PyTorch/torchvision and other dependencies then editable act/detr. Match CUDA environment before training/evaluation.
Upstream documented requirement/configuration only, not independently tested installation or compatibility.
Project notes
Start with the documented simulation
The README creates a Python 3.8.10 conda environment, pins mujoco 2.3.7 and dm_control 1.0.14, installs PyTorch/torchvision and other dependencies, then installs act/detr in editable mode. Most of those other packages are unpinned. The inspected training/evaluation source calls CUDA, so the listed environment commands are not evidence of a CPU-only route or a complete compatible GPU stack. No environment was installed here. [1] [4]
A bounded starting task is sim_transfer_cube_scripted. The README records 50 scripted episodes with record_sim_episodes.py and a selected dataset directory before training through imitate_episodes.py. constants.py still contains a DATA_DIR placeholder; its task configuration names 50 episodes, a 400-step episode and the top camera. Replace paths and inspect the task before attempting the commands. These are source instructions, not data collected by this review. [1] [5]
A checkpoint needs its data statistics
The selected training source fixes state_dim to 14, configures the query count from chunk_size and saves dataset_stats.pkl beside the checkpoint. During evaluation it restores those statistics and converts predicted normalized actions using action_std and action_mean. utils.py separately normalizes joint positions and actions from the training data. Retain that exact task/action convention and statistics when moving a checkpoint; exchanging only a weight file does not establish meaningful commands for another embodiment. [4] [6]
The documented example uses chunk_size 100 and exposes temporal aggregation as an additional flag. Those choices belong to a specific policy/configuration, not an assurance of smooth physical motion. The README's example success rates and training tips remain author reports; no inference, rollout, normalization check or benchmark was run here. [1]
The repository's MIT notice concerns its code. Linked demonstrations, simulator assets and ALOHA hardware have separate sources and rights. No external demonstration payload or pretrained checkpoint was validated, and no real robot interface was connected. [1] [2]
What we checked
Source review only; no environment, dataset, policy inference/training or hardware connection executed.
Not yet established
- Requirements: operating system, host computer
- Version-specific hardware compatibility (ecosystem tags alone do not establish it)
Updates
- Upstream last updated
- Not established
- Latest release
- Not established
- Profile updated
- Nov 1, 2026
- Sources last checked
- Nov 1, 2026
- Next review
- Dec 1, 2026
- Reviewed revision
742c753
Source files and licenses
Distinct imitation-policy implementation and simulation workflow; separate from the ALOHA mechanical platform and external demonstrations.
| Layer | Availability / license |
|---|---|
| software | available · MIT MIT code notice; external demonstrations, robot assets and hardware sources require their own rights review. [1] [2] [3] [4] [5] [6] |
| documentation | available · MIT MIT code notice; external demonstrations, robot assets and hardware sources require their own rights review. [1] [2] [3] [4] [5] [6] |
No separate physical design, pretrained distribution or dataset is selected as the released contribution in this scoped software review.
References
Each source links to the exact revision we read. “Used for” shows where this page relies on it.
- S001 README.md
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· README.md at · Accessed Nov 1, 2026
Used for: Overview, Is this for you?, What you need, Installation & first result and 3 more - S002 LICENSE
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· LICENSE at · Accessed Nov 1, 2026
Used for: Is this for you?, What you need, Installation & first result, A checkpoint needs its data statistics and 1 more - S003 policy.py
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· policy.py at · Accessed Nov 1, 2026
Used for: Overview, Is this for you?, What you need, Installation & first result and 1 more - S004 imitate_episodes.py
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· imitate_episodes.py at · Accessed Nov 1, 2026
Used for: Is this for you?, What you need, Installation & first result, Start with the documented simulation and 2 more - S005 constants.py
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· constants.py at · Accessed Nov 1, 2026
Used for: Is this for you?, What you need, Installation & first result, Start with the documented simulation and 1 more - S006 utils.py
Revision, date & where cited
tonyzhaozh/act contributors · github.com · revision
742c753· utils.py at · Accessed Nov 1, 2026
Used for: Is this for you?, What you need, Installation & first result, A checkpoint needs its data statistics and 1 more
Correction guidance · Discussion is not enabled · Profile format 0.7.0-draft.5