Logical consistency verification of state sensing in safety‐critical decision: A case study of train routing selection

Abstract

Reliable decision-making in a safety-critical system depends on the consistency of the state of the system process. Based on the decision-makeing properties of safety-critical systems, the definition of the critical component, Boolean evolution system, and cognate variables are presented here. By exploring the two lemmas of the critical components, the consistency of the safety-critical system is defined, then a new process of a safety-critical decision of consistency checking is proposed. In order to check the consistency properties of the decision, two computation tree logic formulas derived from the lemmas of the consistency checking are developed. The case of the train routing selection is modelled and verified by model checking, which shows the decision prototype guarantees the safety of the critical process. As the turnout is the critical component in the process of the train routing selection, a multi-sensor-based unit of state monitoring is developed, and a real-world test shows the accuracy of the monitoring unit. This study confirms that the state consistency verification ensures the reliability of the safety-critical system's decision output. The case can enlighten the development of the intelligent control system which has a critical component of decision-making.