aiqbench analysis
This research introduces a hierarchical Soft Actor-Critic framework designed to improve exploration efficiency in sparse-reward, long-horizon reinforcement learning tasks. By decoupling high-level strategic planning from low-level continuous control with entropy regularization, the method achieves superior success rates and convergence compared to flat baseline models on complex search-and-rescue scenarios. The approach represents a significant advancement for autonomous agents operating in environments where rewards are infrequent and delayed.
Hierarchical Soft Actor-Critic for Sparse-Reward Long-Horizon Reinforcement Learning
arXiv:2607.23726v1 Announce Type: new Abstract: Exploration in sparse-reward long-horizon tasks poses significant challenges for reinforcement learning. To address these challenges, we propose a two-level Hierarchical Reinforcement Learning (HRL) framework. The first level handles high-level strategic planning, while the low-level uses the continuous-control Soft Actor-Critic (SAC) algorithm, and they utilize entropy-regularized policy optimization. The proposed framework was trained and evaluated using the Search-and-Rescue-2 (SAR-2) dataset. HRL-SAC effectively addresses sparse-reward long-horizon search problems characterized by delayed rewards and continuous control, and its outperforming the flat SAC baseline reinforcement learning in terms of success rates, coverage efficiency, and convergence. These findings indicate that hierarchical entropy-regularized policies are a promising solution to tackle long-horizon sparse-reward reinforcement learning tasks.
Abstract:Exploration in sparse-reward long-horizon tasks poses significant challenges for reinforcement learning. To address these challenges, we propose a two-level Hierarchical Reinforcement Learning (HRL) framework. The first level handles high-level strategic planning, while the low-level uses the continuous-control Soft Actor-Critic (SAC) algorithm, and they utilize entropy-regularized policy optimization. The proposed framework was trained and evaluated using the Search-and-Rescue-2 (SAR-2) dataset. HRL-SAC effectively addresses sparse-reward long-horizon search problems characterized by delayed rewards and continuous control, and its outperforming the flat SAC baseline reinforcement learning in terms of success rates, coverage efficiency, and convergence. These findings indicate that hierarchical entropy-regularized policies are a promising solution to tackle long-horizon sparse-reward reinforcement learning tasks.
Robotics (cs.RO); Machine Learning (cs.LG)
arXiv:2607.23726 [cs.RO]
(or arXiv:2607.23726v1 [cs.RO] for this version)
https://doi.org/10.48550/arXiv.2607.23726 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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