Cosmos Policy: Fine-Tuning Video Models for Visuomotor Control and Planning

ICLR 2026 Conference Submission23819 Authors

Keywords: world models, robotics, manipulation, model-based planning, imitation learning, video generation

TL;DR: Cosmos Policy is a simple framework for adapting a large pretrained video model (Cosmos-Predict2) into a state-of-the-art robot policy that can generate actions, future states, and values and plan action trajectories with high success rates.

Abstract: Recent video generation models demonstrate remarkable ability to capture complex physical interactions and scene evolution over time. To leverage their spatiotemporal priors, robotics works have adapted video models for policy learning but introduce complexity by requiring multiple stages of post-training and new architectural components for action generation. In this work, we introduce Cosmos Policy, a simple approach for adapting a large pretrained video model (Cosmos-Predict2) into an effective robot policy through a single stage of post-training on the robot demonstration data collected on the target platform, with no architectural modifications. Cosmos Policy learns to directly generate robot actions encoded as latent frames within the video model's latent diffusion process, harnessing the model's rich priors and core learning algorithm to capture complex action distributions. Additionally, Cosmos Policy generates future state images and values (expected total cumulative rewards), which are similarly encoded as latent frames, enabling test-time planning of action trajectories with higher likelihood of success. In our evaluations, Cosmos Policy achieves state-of-the-art performance on the LIBERO and RoboCasa simulation benchmarks (98.5\% and 66.9\% average success rates, respectively) and the highest average score in challenging real-world bimanual manipulation tasks, outperforming strong diffusion policies trained from scratch, video model-based policies, and state-of-the-art vision-language-action models fine-tuned on the same robot demonstrations. Furthermore, given policy rollout data, Cosmos Policy can learn from experience to refine its world model and value function and leverage model-based planning to achieve even higher success rates in challenging tasks.

Primary Area: applications to robotics, autonomy, planning

Submission Number: 23819