Reinforcement learning (RL) has revolutionized decision-making across a wide range of domains over the past few decades. Yet, deploying RL policies in real-world scenarios presents the crucial challenge of ensuring safety. Traditional safe RL approaches have predominantly focused on incorporating predefined safety constraints into the policy learning process. However, this reliance on predefined safety constraints poses limitations in dynamic and unpredictable real-world settings where such constraints may not be available or sufficiently adaptable. Bridging this gap, we propose a novel approach that concurrently learns a safe RL control policy and identifies the unknown safety constraint parameters of a given environment. Initializing with a parametric signal temporal logic (pSTL) safety specification and a small initial labeled dataset, we frame the problem as a bilevel optimization task, intricately integrating constrained policy optimization, using a Lagrangian-variant of the twin delayed deep deterministic policy gradient (TD3) algorithm, with Bayesian optimization for optimizing parameters for the given pSTL safety specification. Through experimentation in comprehensive case studies, we validate the efficacy of this approach across varying forms of environmental constraints, consistently yielding safe RL policies with high returns. Furthermore, our findings indicate successful learning of STL safety constraint parameters, exhibiting a high degree of conformity with true environmental safety constraints. The performance of our model closely mirrors that of an ideal scenario that possesses complete prior knowledge of safety constraints, demonstrating its proficiency in accurately identifying environmental safety constraints and learning safe policies that adhere to those constraints.

我们提出了一种新的方法，同时学习安全的强化学习控制策略并识别给定环境的未知的安全约束参数，通过使用参数化信号时态逻辑 (pSTL) 安全规范和小规模初始标记数据集，将问题作为双层优化任务，通过使用拉格朗日变体的双延迟深度确定性策略梯度 (TD3) 算法的约束策略优化，并结合贝叶斯优化来优化给定 pSTL 安全规范的参数。通过全面的案例研究实验证实了该方法在各种环境约束形式上的有效性，始终产生高回报的安全强化学习策略。此外，我们的研究结果表明成功学习了 STL 安全约束参数，与真实环境安全约束具有高度一致性。我们模型的表现与完全了解安全约束的理想情况非常相似，表明其能够准确识别环境安全约束并学习遵守这些约束的安全策略。

强化学习中策略和未知安全约束的并发学习