Runtime safety assurance methods for cyber physical systems based on simplex architecture.

Runtime safety assurance is a method that can ensure security attributes being satisfied during system operation. The simplex architecture-based runtime safety assurance methods are able to provide the safety guarantees even in the presence of unverified complex controllers. The basic idea is to combine the complex controller with a rigorously formalized safe controller, where the former operates in the absence of safety risk. Whenever a potential safety risk is detected, a decision module then completes the switching between the complex controller and the safe controller in order to guarantee the safety. This paper investigates the runtime safety assurance methods for cyber physical systems and summarizes the most relevant work from three aspects: the design of simplex decision-making module, the extension and improvement of simplex architecture, and the application of simplex architecture. This paper also provides an analysis of technical challenges and future directions of simplex architecture-based runtime safety assurance methods, indicating their potential and effectiveness in solving the runtime safety assurance issues in intelligent cyber-physical systems. [ABSTRACT FROM AUTHOR]