Reset-based recovery for real-time cyber-physical systems with temporal safety constraints
Reset-based recovery for real-time cyber-physical systems with temporal safety constraints
复制标题
DOI：
10.1109/etfa.2016.7733561
复制
发表时间：
2016-09
期刊：
影响因子：
--
通讯作者：
Fardin Abdi Taghi Abad;R. Mancuso;Stanley Bak;Or D. Dantsker;M. Caccamo
中科院分区：
文献类型：
--
作者：
Fardin Abdi Taghi Abad;R. Mancuso;Stanley Bak;Or D. Dantsker;M. Caccamo
在传统的计算系统中，软件问题通常通过平台重启来解决。然而，这种方法不能在网络物理系统(CP)中活跃地使用。(naï)事实上，在这类系统中，确保安全严格依赖于尊重硬实时约束的能力。已经提出了对Simplex体系结构的几种适应，以确保安全，尽管软件组件行为不佳。然而，将恢复到完全可操作状态的问题尚未得到广泛解决。在这项工作中，我们讨论了如何在CPS中使用重置作为一种有效的策略来从各种软件故障中恢复。我们的工作在多个方向上扩展了Simplex架构。首先，我们给出了保证安全的充分条件，即使故障引起的重置。其次，我们引入了一种新的技术，不仅像单纯形中通常所做的那样，表示依赖于状态的安全约束，而且还表示依赖于时间的安全属性。最后，通过在小型R/C直升机上的概念验证最小实现和基于仿真的系统建模，证明了在假定的故障模型下所提出的恢复策略的有效性。
In traditional computing systems, software problems are often resolved by platform restarts. This approach, however, cannot be naïvely used in cyber-physical systems (CPS). In fact, in this class of systems, ensuring safety strictly depends on the ability to respect hard real-time constraints. Several adaptations of the Simplex architecture have been proposed to guarantee safety in spite of misbehaving software components. However, the problem of performing recovery into a fully operational state has not been extensively addressed. In this work, we discuss how resets can be used in CPS as an effective strategy to recover from a variety of software faults. Our work extends the Simplex architecture in a number of directions. First, we provide sufficient conditions under which safety is guaranteed in spite of fault-induced resets. Second, we introduce a novel technique to express not only state-dependent safety constraints, as typically done in Simplex, but also time-dependent safety properties. Finally, through a proof-of-concept minimal implementation on a small R/C helicopter and simulation-based system modeling, we show the effectiveness of the proposed recovery strategy under the assumed fault model.