Sensor attack detection and isolation based on sliding mode observer for cyber‐physical systems

Abstract

SummaryThis article investigates the sensor attack detection and isolation problems for cyber‐physical systems under attacked situation. To begin with, an overall system is constructed for the network of dynamic system and all the issues are dealt with for the overall system instead of every subsystem. Then, we prove that the preconditions which are made on the original subsystem can be transferred on to the overall system. After this, for the overall system, a sliding mode observer that is robust to the disturbance but sensitive to the sensor attack is designed as sensor attack detector to issue an alarm when at least one subsystem is attacked. In addition, we cope with the sensor fault isolation problem by building an augmented descriptor system for the overall system and we further prove that the precondition can be kept for the augmented descriptor system. Then, another robust sliding mode observer is designed to reach the goal of attack isolation. Finally, a simulation example is given to verify the effectiveness of the proposed methods.