π0.5 (pi-zero point five)

π0.5 (pi-zero point five) is Physical Intelligence's upgraded generalist VLA robot foundation model, released September 2025. It is an improved version of π0 with better open-world generalization for mobile manipulators, trained via a technique called knowledge insulation. Pre-trained on 10,000+ hours of robot data with the same flow-matching VLA architecture as π0. Released through the openpi repository alongside π0-FAST. Available as base checkpoints for fine-tuning and expert checkpoints for LIBERO and DROID. Licensed under a custom Physical Intelligence license.