论文标题
LTLF在部分可观察性下合成:从理论到实践
LTLf Synthesis under Partial Observability: From Theory to Practice
论文作者
论文摘要
LTL合成是从线性时间逻辑中形式规范合成反应系统的问题。允许部分可观察性的扩展,即系统无法直接访问有关环境的所有相关信息,可以将此问题推广到更广泛的现实世界应用程序,但是在实践中实施此类扩展的困难意味着它仍然存在于理论领域中。最近,已经证明,通过将LTL与有限的Horizon语义(LTLF)一起使用LTL限制了具有有限执行的系统的系统,可以在实践中实现更简单的实现。通过LTLF的概念简单性,可以首次探索诸如实践中部分可观察性之类的扩展。先前的工作在理论上分析了LTLF合成的问题,并提出了两种可能的算法,一种具有3个exptime,另一个具有2时复杂性。在这项工作中,我们首先证明了早期工作中的复杂性下限。然后,我们通过展示如何将两种算法在实践中集成到LTLF合成的既定框架中来补充理论分析。此外,我们确定了该框架启用的第三个基于MSO的方法。我们的实验评估揭示了与该理论似乎所暗示的非常不同的结果,而3期算法通常优于2Exptime方法。此外,只要能够克服最初的内存瓶颈,基于MSO的方法通常可以超过其他方法。
LTL synthesis is the problem of synthesizing a reactive system from a formal specification in Linear Temporal Logic. The extension of allowing for partial observability, where the system does not have direct access to all relevant information about the environment, allows generalizing this problem to a wider set of real-world applications, but the difficulty of implementing such an extension in practice means that it has remained in the realm of theory. Recently, it has been demonstrated that restricting LTL synthesis to systems with finite executions by using LTL with finite-horizon semantics (LTLf) allows for significantly simpler implementations in practice. With the conceptual simplicity of LTLf, it becomes possible to explore extensions such as partial observability in practice for the first time. Previous work has analyzed the problem of LTLf synthesis under partial observability theoretically and suggested two possible algorithms, one with 3EXPTIME and another with 2EXPTIME complexity. In this work, we first prove a complexity lower bound conjectured in earlier work. Then, we complement the theoretical analysis by showing how the two algorithms can be integrated in practice into an established framework for LTLf synthesis. We furthermore identify a third, MSO-based, approach enabled by this framework. Our experimental evaluation reveals very different results from what the theory seems to suggest, with the 3EXPTIME algorithm often outperforming the 2EXPTIME approach. Furthermore, as long as it is able to overcome an initial memory bottleneck, the MSO-based approach can often outperforms the others.