๐ค AI Summary
This work addresses the challenges of high-dimensional continuous control, where existing policy optimization methods often suffer from local optima, sensitivity to initialization, and prohibitively expensive global exploration. The authors propose TFM-S3, a novel approach that introduces a pretrained tabular foundation model into robotic policy learning for the first time. By dynamically constructing a low-dimensional policy subspace and combining high-frequency local updates with intermittent global search, TFM-S3 achieves efficient exploration and rapid convergence at low sample cost. The method integrates singular value decomposition, surrogate-model-guided optimization, and the TD3 framework, demonstrating significantly accelerated early-stage convergence on standard continuous control benchmarks and outperforming both TD3 and population-based methods under identical interaction budgets.
๐ Abstract
Policy optimization in high-dimensional continuous control for robotics remains a challenging problem. Predominant methods are inherently local and often require extensive tuning and carefully chosen initial guesses for good performance, whereas more global and less initialization-sensitive search methods typically incur high rollout costs. We propose TFM-S3, a tabular hybrid local-global method for improving global exploration in robot policy learning with limited rollout cost. We interleave high-frequency local updates with intermittent rounds of global search. In each search round, we construct a dynamically updated low-dimensional policy subspace via SVD and perform iterative surrogate-guided refinement within this space. A pretrained tabular foundation model predicts candidate returns from a small context set, enabling large-scale screening with limited rollout cost. Experiments on continuous control benchmarks show that TFM-S3 consistently accelerates early-stage convergence and improves final performance compared to TD3 and population-based baselines under an identical rollout budget. These results demonstrate that foundation models are a powerful new tool for creating sample-efficient policy learning methods for continuous control in robotics.