π0

π0 (pi-zero) was announced by Physical Intelligence on October 31, 2024 (arXiv 2410.24164) as the company's first general-purpose robot foundation model. It is a vision-language-action policy: a ~3B-parameter PaliGemma vision-language backbone provides semantic understanding, and a ~300M-parameter action expert generates continuous motor commands via flow matching at up to 50Hz, trained across 8 robot platforms and dozens of dexterous tasks such as folding laundry and assembling boxes.

The model was open-sourced in February 2025 through the openpi repository (Apache 2.0 code) with checkpoints usable in Hugging Face's LeRobot stack. One licensing nuance worth knowing: the checkpoint inherits Google's Gemma Terms of Use through its PaliGemma backbone, which carries a prohibited-use policy, so read both licenses before deploying beyond research.