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arXiv · 1910.14127

Self-Repairing Hardware Architecture for Safety-Critical Cyber-Physical-Systems

Shawkat Khairullah·Carl Elks
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Abstract

Digital embedded systems in safety-critical cyber-physical-systems (CPSs) require high levels of resilience and robustness against different fault classes. In recent years, self-healing concepts based on biological physiology have received attention for the design and implementation of reliable systems. However, many of these approaches have not been architected from the outset with safety in mind, nor have they been targeted for the safety-related automation industry where the significant need exists. This study presents a new self-healing hardware architecture inspired by integrating biological concepts, fault tolerance techniques, and IEC 61131-3 operational schematics to facilitate adaption in automation and critical infrastructure. The proposed architecture is organised in two levels: the critical functions layer used for providing the intended service of the application and the healing layer that continuously monitors the correct execution of that application and generates health syndromes to heal any failure occurrence inside the functions layer. Finally, two industrial applications have been mapped on this architecture to date, and the authors believe the nexus of its concepts can positively impact the next generation of critical CPSs in industrial automation.

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Shawkat Khairullah, Carl Elks. 2020-03-25. Self-Repairing Hardware Architecture for Safety-Critical Cyber-Physical-Systems. https://doi.org/10.1049/iet-cps.2019.0022

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