Vulnerabilities and safety assurance methods in Cyber-Physical Systems: a comprehensive review

As Cyber-Physical Systems (CPSs) are a class of systems advancing in a number of safety critical application areas, it is crucial to ensure that they operate without causing any harm to people, environment and assets. The complexity of CPSs though, render them vulnerable and accident-prone. In this study, the sources of complexity are meticulously examined and the state-of-the-art and novel methods that are used for the safety assurance of CPSs are reviewed. Furthermore, the identified safety assurance methods are assessed for their compatibility with the technical processes during the system design phase and the methods effectiveness on addressing the different CPSs sources of complexity is investigated. Advantages and disadvantages of the different safety assurance methods are also presented. Based on the results of this review, directions for the safety enhancement of CPSs and topics for future research in the area of CPSs safety are provided.