Comparison Matrix
Every major policy across eight architectural axes: action representation, horizon, frequency, backbone, conditioning, cross-embodiment, hierarchy, openness.
- Last reviewed
- Reading time
- 16 min
- Citations
- 21
RT-2’s reported rates depend on the model and serving setup. Its 55B PaLI-X variant runs at 1 to 3 Hz, while the 5B variant runs at around 5 Hz, using a multi-TPU cloud service queried over the network. Brohan 2023
OpenVLA v3 reports approximately 6 Hz inference on one NVIDIA RTX 4090 in bfloat16, without compilation, speculative decoding, or other inference speed-up tricks. Kim 2024
18 of 18 methods
| Backbone | Conditioning | Sources | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| RT-1 | 2022 | discrete tokens | 1 / 1 | 3 HzEveryday Robots commanded control; six input images are observation history, not action horizon | FiLM-EfficientNet + TokenLearner + 19M transformer | language, 6-frame image history | limited | none | not disclosedPretrained weights not disclosed in the checked RT-1 paper; its code-release statement is not a weight release | |
| ACT | 2023 | continuous | 100 / 1k=100 ablation reference; temporal ensembling queries the policy every timestep | 50 HzALOHA teleoperation/data-recording setting; task-specific models | ResNet-18 x4 + transformer encoder-decoder, ~80M | 4 RGB cameras, joint positions | not disclosed | none | not disclosedThe checked ACT paper announces software/hardware and per-task training, not downloadable pretrained checkpoints | |
| Diffusion Policy | 2023 | diffusion | 16 / 8CNN Push-T reference: observation horizon 2; not universal settings | 10 HzReal-world UR5 Push-T: 10 Hz predictions interpolated to 125 Hz commands; separate from the reference horizon | ResNet-18 + CNN U-Net or time-series diffusion transformer | 2 observation frames | not disclosed | none | not disclosedThe inspected paper announces code, data and training details; it does not establish downloadable pretrained checkpoints | |
| RT-2 | 2023 | discrete tokens | 1 / 1 | not disclosedMulti-TPU cloud serving: PaLI-X-55B 1-3 Hz; 5B model around 5 Hz. No universal scalar. | PaLI-X / PaLM-E, up to 55B | language, image | limited | none | not disclosedModel-specific weight-release terms are not established by the checked RT-2 paper; not a closed-license claim | |
| Octo | 2024 | diffusion | 64 / 12ALOHA finetuning only; not a universal Octo horizon | not disclosedNo universal rate disclosed; separate setups: Franka prediction 15 Hz, coffee controller 10 Hz, ViperX control 5 Hz | Octo transformer checkpoints: 27M or 93M; pretrained t5-base (111M) language encoder | language or goal image | yes | none | downloadable | |
| OpenVLA | 2024 | discrete tokens | 1 / 1 | not disclosedApproximately 6 Hz inference on RTX 4090 in bfloat16 without speed-up tricks; Franka-Tabletop/DROID controllers are separately 5/15 Hz | Prismatic-7B (LLaMA-2 + DINOv2 + SigLIP) | language, single image | yes | none | downloadableThe paper explicitly releases model checkpoints and describes downloadable models; availability is not a blanket license classification | |
| π0 | 2024 | flow matching | 50 / 16UR5e/Franka reference; other robots execute 25 of 50 | 20 HzUR5e/Franka; other evaluated robots 50 Hz (paper: up to 50 Hz) | PaliGemma (Gemma 2B language model) + ~300M action expert | 2-3 RGB cameras, language, proprioception | yes | none | downloadableThe pinned openpi README lists pi0 base checkpoints; this is download availability, not license openness | |
| OpenVLA-OFT | 2025 | continuous; Parallel bidirectional decoding with an L1-trained four-layer MLP; OFT+ adds FiLM for the ALOHA experiments | 25 / 25OFT+ ALOHA reference: execute the full chunk before replanning. LIBERO separately predicts and executes 8; adaptation is task-specific, not one shared multi-robot checkpoint | 25 HzOFT+ ALOHA controller, reduced from the original 50 Hz. A100 action-generation throughput is separate: 77.9 actions/s with three images and robot state | Prismatic-derived OpenVLA: Llama-2 7B + DINOv2/SigLIP + four-layer L1 MLP | language, 3 ALOHA camera images, robot proprioceptive state | limited | none | downloadableThe OFT v2 paper announces code and pretrained checkpoints. Download availability is source-reported; checkpoint files and their license terms were not inspected. The paper license is not a weights license | |
| π0-FAST | 2025 | discrete tokens; Autoregressive FAST action tokens, decoded back into continuous action chunks | 15 / {8, 15}DROID setup in the FAST v1 paper: predicts 15, executes either 8 or 15; other tasks use one-second chunks at their own rates | 15 HzDROID setup; other evaluated tasks use 20 or 50 Hz. Not inference throughput: the paper reports approximately 750 ms per one-second chunk on NVIDIA 4090 | PaliGemma 3B + FAST DCT/BPE tokenizer | 2-3 RGB cameras, language, proprioception | yes | none | downloadablePinned openpi README lists pi0_fast_base and pi0_fast_droid downloads; availability is not a license classification | |
| π0.5 | 2025 | flow matching | 50 / n.d.50 predictions (inclusive H=49); executed count not disclosed in the v1 paper | 50 Hzv1 paper mobile-manipulation targets; not inference throughput | PaliGemma-initialized VLM + 300M expert (v1 technical appendix labels the VLM 2B) | language, images, web VQA, subtask prediction | yes | internal | downloadableopenpi snapshot lists pi05_base; download availability does not establish license terms | |
| π0.6 | 2025 | flow matching; continuous actions; FAST backbone supervision during training | not disclosedPredicted and executed counts not disclosed in the November 17, 2025 model card | not disclosedRobot-control Hz not disclosed in the model card; 63 ms chunk inference uses five denoising steps, three cameras and one H100 | SigLIP 400M + Gemma3 4B + approximately 860M expert; no total stated in the card | language, up to 4 images, metadata | yes | internal | not disclosedModel-specific weight-release and licensing terms not disclosed in the checked pi0.6 model card | |
| Gemini Robotics 1.5 | 2025 | continuous; The v3 model card states continuous numerical robot actions and text when thinking is enabled; it does not identify a regression, diffusion, or flow-matching action head | not disclosedPredicted and executed action-chunk lengths are not disclosed in the inspected v3 report | not disclosedRobot-command frequency is not disclosed in the inspected v3 report. Its 5 Hz success-detection evaluation concerns GR-ER, not the VLA control loop | Gemini-derived VLA; separate GR-ER 1.5 orchestrator | language, images, natural-language thinking traces when enabled | yes | internal | not disclosedModel-specific weight-download and licensing terms are not disclosed in the inspected v3 technical report; this is not a closed-license finding | |
| π0.7 | 2026 | flow matching; continuous actions; FAST backbone supervision during training | 50 / {15, 25}Five denoising steps; executes either 15 or 25; paper does not map these choices to robots | 20 HzUR5e reference; other tested robots 50 Hz | Gemma3 4B + 860M expert, ~5B | language, subtask, metadata, subgoal images, memory | yes | internal | not disclosedModel-specific weight-release and licensing terms not disclosed in the checked pi0.7 paper | |
| Gemini Robotics 2 | 2026 | not disclosed | not disclosedPredicted and executed chunk lengths are not disclosed in the inspected announcement | not disclosedRobot-command rate and parameter count are not disclosed in the inspected announcement; multi-minute ER tasks are not a control frequency | not disclosed | vision, language | yes | external | not disclosedAnnouncement scope: separate ER 2 coordinates the VLA. One checkpoint covers Apollo 2 with SharpaWave, Apollo 2 with Inspire, and Franka Duo with Robotiq. ER access is via AI Studio/private preview; VLA and On-Device access is for early-access partners. Weight downloads and licensing terms are not disclosed | |
| GR00T N1.7 | 2026 | flow matching | 40 / n.d.N1.7 README model horizon; executed count is rollout-dependent, not disclosed as one value | not disclosedNo universal robot-control Hz disclosed in the checked N1.7 README; inference throughput is not control frequency | Cosmos-Reason2-2B (Qwen3-VL), 3B total | language, images, state (dim 132) | yes | external | downloadableGA README lists downloadable weights; License section: code Apache 2.0, weights NVIDIA Open Model License | |
| Helix 02 | 2026 | not disclosed | not disclosedChunk length not disclosed in the January 27, 2026 announcement; not inapplicable | 200 HzFigure announcement: S1 full-body joint targets at 200 Hz; S0 actuator commands at 1 kHz | S2 semantic layer + S1 visuomotor transformer + S0 10M | head and palm cameras, fingertip tactile, full-body proprioception | not disclosed | internal | not disclosedWeight-release and licensing terms not disclosed in this announcement | |
| AgiBot GO-2 | 2026 | not disclosed | not disclosedPredicted and executed action-chunk lengths are not disclosed in the announcement text | not disclosedSystem 2 semantic planning is lower frequency; System 1 action following is higher frequency. Neither numerical inference rates nor a robot-control Hz value are disclosed | not disclosed | instructions, real-time observations | not disclosed | internal | not disclosedTrained GO-2 weight-release and licensing terms are not established by the inspected announcement; this is not a closed-license finding | |
| Skild | 2026 | not disclosed | not disclosedPredicted and executed chunk lengths are not disclosed in the inspected announcement | not disclosedControl frequency and parameter count are not disclosed in the inspected announcement | not disclosed | not disclosed | not disclosed | not disclosed | not disclosed2026 is the Series C announcement year, not an established model-release year. Architecture, runtime inputs, hierarchy, weight downloads and licensing terms are not disclosed in that source. Omni-bodied generalization is a company assertion, not a demonstrated transfer protocol |
The eight axes
Action representation describes the output mechanism: continuous regression, discrete action tokens, or a generative head such as diffusion or flow matching. Training supervision and runtime action generation need not use the same representation.
Horizon separates the planned chunk length from the steps executed before re-planning: the predicted horizon and the committed horizon. Chi 2023 The Diffusion Policy CNN Push-T configuration predicts 16 steps and executes 8; these are not universal settings for every architecture or task. Ai 2026 π0.7 predicts 50 and executes either 15 or 25, not every integer between them. Its paper does not map those two execution choices to particular robots.
Control frequency needs a named measurement setting. Zhao 2023 ACT's ALOHA setup runs at 50 Hz; with temporal ensembling, the policy is queried at every timestep. Brohan 2022 RT-1 commands the Everyday Robots platform at 3 Hz. Neither statement is a standalone transformer-throughput benchmark.
Backbone, conditioning, and cross-embodiment describe the model components, their inputs, and the scope of robot-body transfer. Distinguish mixed-embodiment training, direct use of a checkpoint on multiple bodies, and finetuning on a new body rather than treating them as equivalent evidence of transfer.
Hierarchy distinguishes an internal high-level stage from a separately paired system. Black 2025 π0.5 predicts a semantic subtask before generating low-level actions. NVIDIA 2026 In the N1.7 SONIC workflow, a separate whole-body controller decodes the VLA's latent action tokens into joint commands. Here, external does not mean that the controller is a reasoning layer above the policy. Weights records download availability, not license openness; the notes identify the checked source scope.
Brohan 2022 RT-1’s “limited” cross-embodiment label refers to mixing Kuka IIWA data with Everyday Robots data, then evaluating on Everyday Robots. It does not mean that one checkpoint was demonstrated controlling both robot bodies.
Zhao 2023 ACT’s 100-step entry names the paper’s k=100 chunk-ablation reference; temporal ensembling queries the policy every timestep. The paper trains a roughly 80M-parameter model from scratch for each task and announces software and hardware. That does not establish pretrained-checkpoint downloads or one checkpoint transferring across embodiments; those cells are source-scoped as not disclosed.
Chi 2023 Diffusion Policy’s CNN Push-T reference uses observation/prediction/execution horizons of 2/16/8. Its real-world UR5 Push-T experiment predicts commands at 10 Hz and interpolates them to 125 Hz. These are named settings, not defaults for every task or backbone. The checked paper announces code, data and training details, not a pretrained-checkpoint catalogue; no shared-checkpoint cross-embodiment result is established here.
Brohan 2023 RT-2’s multi-TPU cloud service runs PaLI-X-55B at 1 to 3 Hz and the 5B version at around 5 Hz. The paper also studies PaLM-E-12B and a separate Language-Table model. “Limited” denotes these separate setup-specific models, not demonstrated cross-body use of one checkpoint. The action-only table entry excludes the separately evaluated chain-of-thought prompting variant. The inspected paper does not establish model-specific weight-release terms.
Kim 2024 OpenVLA v3 reports approximately 6 Hz inference on one RTX 4090 in bfloat16, without compilation, speculative decoding or other speed-up tricks. Its Franka-Tabletop and Franka-DROID fine-tuning setups separately use 5 Hz and 15 Hz non-blocking controllers. The paper describes single-step action prediction, multi-robot pretrained use and fine-tuning for new setups, and explicitly releases downloadable checkpoints. Its 7B label names the language-model scale; the visual encoder is separately reported as 600M parameters.
Kim 2025 The OFT row uses the paper's ALOHA OFT+ setting: 25 predicted and executed actions at a 25 Hz controller. LIBERO instead predicts and executes eight. Its limited cross-embodiment label means adaptation from the pretrained model to separate tasks and robot setups, not demonstrated control of every body by one unchanged checkpoint.
Gemini Robotics Team 2025 Gemini Robotics 1.5's v3 model card does disclose continuous numerical action outputs. It does not identify the action-head family, action-chunk length, robot-command rate, or parameter count. Internal refers to thinking within the VLA; the report also pairs it with a separate GR-ER 1.5 orchestrator. The generalization and cross-embodiment experiments use one checkpoint across ALOHA, bi-arm Franka, and Apollo; the separate long-horizon agent experiment adds post-training on bi-arm Franka. An unset field here is source-scoped, not inapplicable.
Parada 2026 The Gemini Robotics 2 row describes the VLA in DeepMind's July 30, 2026 announcement. External hierarchy means the separate ER 2 model coordinates with that VLA; it is not an undisclosed internal action head. The same-checkpoint result covers Apollo 2 with SharpaWave hands, Apollo 2 with Inspire hands, and Franka Duo with Robotiq, not every On-Device adaptation. The announcement does not specify the VLA backbone, output parameterization, chunk lengths, control frequency, or parameter count. AI Studio, private preview, and early-access partnerships are access channels, not weight-license classifications.
Skild AI Team 2026 Skild's 2026 row is scoped to its January 14 Series C announcement, not a verified model-release date. The company describes its data sources and makes an omni-bodied capability claim, but does not specify a reproducible cross-embodiment evaluation or the runtime architecture, inputs, hierarchy, chunk lengths, control frequency, and weight-release terms used by these cells. The empty conditioning list means not disclosed in this source, not no inputs or n/a.
Helix 02 and GO-2 disclosure limits
Figure AI 2026 Figure’s Helix 02 announcement describes S1 joint targets at 200 Hz and S0 actuator commands at 1 kHz, but does not specify the output-head training loss. The representation cell is therefore not classified as continuous regression here. Its statement about generalization across Figure’s fleet is not evidence of one checkpoint transferring between different robot bodies; that field remains not disclosed for this source.
AgiBot 2026 AgiBot describes lower-frequency System 2 semantic planning and higher-frequency System 1 action following, not two numerical control rates. The inspected announcement text does not establish the backbone, output encoding, action-chunk lengths, cross-body checkpoint transfer, or trained-policy weight-release terms. Those fields remain not disclosed, rather than n/a or closed. The 2026 year is supported by an HTML publication timestamp in a commented span; it is not an independently established release date.
What the matrix can establish
Zhao 2023 ACT fixes its CVAE latent to the prior mean, zero, to decode deterministically at test time. Black 2024 π0 instead uses an action expert trained with flow matching to generate continuous action chunks. These are concrete differences between output mechanisms, not evidence that every later policy abandoned regression.
Black 2025 The π0.5 paper distinguishes FAST-token training from continuous-action generation with flow matching. It describes autoregressive action decoding as expensive at inference time. That qualitative comparison is not a measured factor-of-two task-completion or inference-latency result for π0-FAST.
Ai 2026 π0.7 uses five denoising steps to generate 50 actions, then executes either 15 or 25. Its UR5e robots run at 20 Hz; the other tested robots run at 50 Hz. Black 2025 Real-time chunking addresses inference delay by guiding generation of the next chunk while the current one is executing. These execution details matter more than ranking methods by predicted horizon alone.
Physical Intelligence 2025 The π0.6 card reports 63 ms to produce an action chunk with five denoising steps, three camera inputs, and one H100. It does not disclose a robot-control rate or a predicted/executed chunk length. Figure AI 2026 Figure reports Helix 02 S1 joint targets at 200 Hz and S0 actuator commands at 1 kHz. The latter are different stages of a control stack, not two alternative speeds for one model call.
Brohan 2022 The RT-1 paper announces code, which does not establish pretrained-weight availability. Figure AI 2026 Figure's Helix 02 announcement does not state a chunk horizon or weight-release terms. Their availability cells therefore read "not disclosed" for these checked sources. Physical Intelligence 2026 The pinned openpi README lists π0, π0-FAST, and π0.5 checkpoints. NVIDIA 2026 The N1.7 README lists downloadable weights, while its License section distinguishes Apache 2.0 code from the NVIDIA Open Model License for weights. These release statements do not establish a global generation ranking or closed licensing for an unlisted model.
The Control Hz column is not an inference-throughput comparison. Zhao 2023 ACT's 50 Hz ALOHA loop, Figure AI 2026 Helix's 200 Hz S1/1 kHz S0 stack, and Ai 2026 π0.7's 20 Hz UR5e/50 Hz other-robot settings describe different systems. π0.7 also trains with simulated inference delays; that does not turn these rates into a shared benchmark. Read the setting notes before comparing two cells.
Use the matrix as a constraint solver
Start with elimination, not ranking. Remove models whose weights or training data cannot be used under the project's terms. Remove models whose action representation cannot map cleanly to the robot's controller, then those whose measured end-to-end latency misses the deadline. Next test observation compatibility and the amount of adaptation data the model requires. Only after those constraints should benchmark performance influence the shortlist.
For the surviving candidates, run one controlled comparison with the same cameras, action horizon, reset policy and physical trial protocol. Keep a simple behavior-cloning or action-chunking baseline in the evaluation. The foundation-model guide explains what prior each family contributes; the action-space guide explains whether its output is a fair fit. A matrix can expose missing evidence, but it cannot turn results from different robots and protocols into a universal leaderboard.
See also
- Vision-Language-Action Models
RT-1, RT-2, RT-X, Octo, and OpenVLA: web-scale pretraining meets robot control, and the cost of discrete action tokens.
- The Pi Line
pi0 to pi0.7: flow-matching action experts, FAST tokenization, open-world generalization, and source-scoped checkpoint availability.
- Foundation Models for Robotics
What foundation means in robotics, how VLA, world-model and multimodal pretraining differ, and what adaptation still costs.
- Action Spaces for Robot Learning
Joint, Cartesian, torque, impedance, chunked and tokenized actions: what each representation gives the learner and pushes onto the controller.
Linked from
- Vision-Language-Action Models
RT-1, RT-2, RT-X, Octo, and OpenVLA: web-scale pretraining meets robot control, and the cost of discrete action tokens.
- Other Generalist Policies
Gemini Robotics, GR00T, Helix, Skild, and GO-2: how to read closed-model vendor claims.
- Hierarchical Approaches
SayCan, code-as-policies, and keypoint affordances; why separate planners gave way to internalized hierarchy.
- Knowledge Insulation
Training the VLM backbone on discrete tokens while a flow-matching expert learns actions behind a stop-gradient.
References
Anthony Brohan, Noah Brown, Justice Carbajal, Yevgen Chebotar, Joseph Dabis, Chelsea Finn, Keerthana Gopalakrishnan, Karol Hausman, and 43 more, 2022.
https://arxiv.org/html/2212.06817v2
Tony Z. Zhao, Vikash Kumar, Sergey Levine, Chelsea Finn, RSS 2023.
https://arxiv.org/abs/2304.13705
Cheng Chi, Zhenjia Xu, Siyuan Feng, Eric Cousineau, Yilun Du, Benjamin Burchfiel, Russ Tedrake, Shuran Song, 2023.
https://arxiv.org/abs/2303.04137
Anthony Brohan, Noah Brown, Justice Carbajal, Yevgen Chebotar, Xi Chen, Krzysztof Choromanski, Tianli Ding, Danny Driess, and 46 more, 2023.
https://arxiv.org/abs/2307.15818
- Octo: An Open-Source Generalist Robot PolicyFurther reading
Octo Model Team, Dibya Ghosh, Homer Walke, Karl Pertsch, Kevin Black, Oier Mees, Sudeep Dasari, Joey Hejna, and 12 more, 2024.
https://arxiv.org/html/2405.12213v2
- Open X-Embodiment: Robotic Learning Datasets and RT-X ModelsFurther reading
Open X-Embodiment Collaboration, Abby O'Neill, Abdul Rehman, Abhinav Gupta, Abhiram Maddukuri, Abhishek Gupta, Abhishek Padalkar, Abraham Lee, and 286 more, 2023.
https://arxiv.org/abs/2310.08864
Moo Jin Kim, Karl Pertsch, Siddharth Karamcheti, Ted Xiao, Ashwin Balakrishna, Suraj Nair, Rafael Rafailov, Ethan Foster, and 10 more, 2024.
https://arxiv.org/abs/2406.09246
Moo Jin Kim, Chelsea Finn, Percy Liang, 2025.
https://arxiv.org/abs/2502.19645
Kevin Black, Noah Brown, Danny Driess, Adnan Esmail, Michael Equi, Chelsea Finn, Niccolo Fusai, Lachy Groom, and 16 more, RSS 2025, 2024.
https://arxiv.org/abs/2410.24164
Karl Pertsch, Kyle Stachowicz, Brian Ichter, Danny Driess, Suraj Nair, Quan Vuong, Oier Mees, Chelsea Finn, and 1 more, 2025.
https://arxiv.org/abs/2501.09747
Physical Intelligence, Kevin Black, Noah Brown, James Darpinian, Karan Dhabalia, Danny Driess, Adnan Esmail, Michael Equi, and 28 more, 2025.
https://arxiv.org/html/2504.16054v1
Physical Intelligence, 2026.
https://github.com/Physical-Intelligence/openpi/blob/215abfb217dbac7d5f1273282331b9b1866c0479/README.md
Physical Intelligence, 2025.
https://website.pi-asset.com/pi06star/PI06_model_card.pdf
Bo Ai, Ali Amin, Raichelle Aniceto, Ashwin Balakrishna, Greg Balke, Kevin Black, George Bokinsky, Shihao Cao, and 79 more, 2026.
https://www.pi.website/download/pi07.pdf
Gemini Robotics Team, Abbas Abdolmaleki, Saminda Abeyruwan, Joshua Ainslie, Jean-Baptiste Alayrac, Montserrat Gonzalez Arenas, Ashwin Balakrishna, Robert Baruch, and 165 more, 2025.
https://arxiv.org/abs/2510.03342
Carolina Parada, 2026.
https://deepmind.google/blog/gemini-robotics-2-brings-whole-body-intelligence-to-robots/
AgiBot, 2026.
https://www.agibot.com/article/231/detail/56.html
Kevin Black, Manuel Y. Galliker, Sergey Levine, 2025.
https://arxiv.org/abs/2506.07339
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