PDRVLA pulled physical dynamics out of a frozen video world model instead of generating video at inference time, and hit 99.3 percent on LIBERO
AspireAI community · arXiv
*Vision-language-action models generate robot actions from images and instructions but have limited grip on physical dynamics, and the usual fix - running a video world model online - puts a heavy generative model inside the control loop.* PDRVLA's answer is a lightweight Physical Dynamics Module that pulls physical tokens out of vision-language features and conditions action generation without any online video generation. The module learns by directly predicting future RGB, depth and optical-flow features, with auxiliary supervision from a frozen pretrained video world model, and training relies entirely on publicly available data expanded through human-to-robot synthesis, subtask annotation and embodied chain-of-thought annotation. Success rates reach 99.3 percent on LIBERO, 89.9 percent on LIBERO-Plus, 93.6 percent on RoboTwin 2.0 and 81.5 percent on SimplerEnv. The limitation: the headline numbers are simulation, and the ablations attribute part of the gain to the world-model supervision rather than to the architecture alone.
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