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arXiv · 2606.14375

Elastic Queries Reinforcement Learning: Self-Aware Policy Execution for VLA Models

Abstract

Vision-language-action (VLA) models are powerful action generators for robot manipulation, but they are typically executed with fixed inference and replanning schedules. This rigidity ignores the uneven difficulty of robot control: contact-rich or uncertain states may need more computation and fresher feedback, while easier states can often be handled with fewer inference steps and longer open-loop execution. We propose Elastic Queries Reinforcement Learning (EQRL), a framework that makes each VLA policy query elastic. A lightweight latent-schedule adaptor jointly selects the latent input, denoising budget, and action chunk length, without fine-tuning the underlying VLA model. To make scheduling difficulty-aware, EQRL trains a critic over the joint latent-schedule action and derives a state difficulty signal from critic ensemble disagreement. This signal guides compute toward difficult states, while a learned residual allows task-driven correction. We formulate variable chunk execution as query-level macro-action RL with chunk-dependent discounting and an amortized number-of-function-evaluations (NFE) budget. Across simulation and real-robot manipulation, EQRL reduces amortized inference cost while preserving or improving task success.

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Ge Wang, Xinyu Tan, Xiang Li, Man Luo, Chengsi Yao, Shenhao Yan, Jiahao Yang, Fan Feng, Honghao Cai, Xiangyuan Wang, Zhixin Mai, Yiming Zhao, Yatong Han, Zhen Li. 2026-06-12. Elastic Queries Reinforcement Learning: Self-Aware Policy Execution for VLA Models. https://arxiv.org/abs/2606.14375

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