Brain
Physical Intelligence's pi0.5 (also written pi-0.5) is a vision-language-action model built on the company's pi0, adding open-world generalization by co-training on heterogeneous data including multi-robot trajectories, web data, high-level semantic subtask prediction, object detections, and verbal instructions, with a paper submitted on April 22, 2025. Its capability frontier is notable: it was the first end-to-end learned system demonstrated doing long-horizon dexterous manipulation, such as cleaning entire kitchens and bedrooms, in entirely new homes not present in its training data, running on mobile manipulators. It is recorded in the registry as built on pi0, the roughly 3-billion-parameter vision-language-action flow model that Physical Intelligence open-sourced in February 2025 via the openpi repository as the first robotics foundation model on Hugging Face's LeRobot. The registry records pi0.5 at research maturity: it was shown in research demonstrations in previously unseen homes rather than a named-customer rollout, and unlike pi0 its own checkpoint release is not verified, so it is marked closed pending confirmation, with its parameter count not stated in the paper abstract. This record also corrects the prior pi0 entry, which mis-dated pi0.5 to September 2025; the paper is April 22, 2025.
Foundation model · Maturity: Research · Closed
Machine-readable surfaces
- Markdown mirror: /brains/pi05.md
- RSS feed: /brains/pi05/feed.xml
- JSON-LD: embedded in this page’s head
- REST API: /v1/brains/83b7c9c1-40b4-4823-b7b6-23046fce0f9c
- Data documentation: /data
Architecture
Vision-language-action model built on pi0; co-trained on heterogeneous multi-robot + web data with high-level semantic subtask prediction for open-world generalization.
Key facts
- Model
- pi0.5 (pi-0.5): a vision-language-action model built on pi0 adding OPEN-WORLD GENERALIZATION via co-training on heterogeneous data (multi-robot, web data, high-level semantic subtask prediction, object detections, verbal instructions). Paper submitted Apr 22 2025 (arXiv 2504.16054).
- Capability frontier
- First end-to-end learned system to do long-horizon dexterous manipulation (cleaning entire kitchens/bedrooms) in entirely NEW homes not in training data; runs on mobile manipulators.
- Built on
- pi0 (the ~3B-param VLA flow model; pi0 was open-sourced Feb 2025 via openpi, first robotics FM on Hugging Face LeRobot). builtOnBrainId -> pi0.
- Cap-flag
- Deployed as RESEARCH demonstrations in new homes, NOT a named-customer rollout. pi0.5 OPEN-SOURCE/checkpoint release is NOT verified (vs pi0 which is confirmed open) - isOpen=false pending confirmation. pi0.5 parameter count not stated in the paper abstract.
Developed by (1)
Built on
pi0 (and pi0.5)(this brain is an OS-layer or extension built atop another brain)
Common questions
- What is pi0.5 (pi-0.5)?
- Physical Intelligence's pi0.5 (also written pi-0.5) is a vision-language-action model built on the company's pi0, adding open-world generalization by co-training on heterogeneous data including multi-robot trajectories, web data, high-level semantic subtask prediction, object detections, and verbal instructions, with a paper submitted on April 22, 2025. Its capability frontier is notable: it was the first end-to-end learned system demonstrated doing long-horizon dexterous manipulation, such as cleaning entire kitchens and bedrooms, in entirely new homes not present in its training data, running on mobile manipulators. It is recorded in the registry as built on pi0, the roughly 3-billion-parameter vision-language-action flow model that Physical Intelligence open-sourced in February 2025 via the openpi repository as the first robotics foundation model on Hugging Face's LeRobot. The registry records pi0.5 at research maturity: it was shown in research demonstrations in previously unseen homes rather than a named-customer rollout, and unlike pi0 its own checkpoint release is not verified, so it is marked closed pending confirmation, with its parameter count not stated in the paper abstract. This record also corrects the prior pi0 entry, which mis-dated pi0.5 to September 2025; the paper is April 22, 2025.
- What type of AI is pi0.5 (pi-0.5)?
- pi0.5 (pi-0.5) is a foundation model on the DEPLOY registry. It is proprietary.
- Who developed pi0.5 (pi-0.5)?
- pi0.5 (pi-0.5) is credited to Physical Intelligence on the DEPLOY registry. Each developer attribution is verified via primary sources.
- Which robots run on pi0.5 (pi-0.5)?
- No robot models on the DEPLOY registry are recorded as running pi0.5 (pi-0.5). DEPLOY wires brain-to-model connections only when the wiring is verifiable from primary sources; absence may reflect pre-deployment or unverified manufacturer claims.
- Is pi0.5 (pi-0.5) open source?
- No. pi0.5 (pi-0.5) is recorded as proprietary on the DEPLOY registry. Model weights and source are not publicly available.
- What is pi0.5 (pi-0.5)'s maturity stage?
- pi0.5 (pi-0.5) is at the research stage on the DEPLOY maturity ladder. Research stage means active development without commercial deployments on file.
Sources (3)
Canonical ID 83b7c9c1-40b4-4823-b7b6-23046fce0f9c