Observer-Based DETM-Switching- H∞ Control for Disturbed Servo Systems Under DoS Attacks

This article investigates the secure control of a class of servo DC motors in the presence of input-output disturbances and DoS attacks. A multichannel observer-based switching H∞ control strategy is proposed and a dynamic event triggering mechanism (DETM) is designed to save network resources. First, a mathematical model of servo DC motor containing input-output disturbances is developed and discretized to make it more suitable for computer control. Then, a state observer and a multichannel transmission strategy based on Markov theory are designed in order to obtain the accurate knowledge of disturbed system and transmit it to the remote controller under DoS attack. Third, observer-based state feedback switching H∞ control strategy is proposed and the stability is demonstrated. Furthermore, the DETM is presented to reduce the occupation of network resources by introducing dynamic trigger variable. Finally, the performance of the characterized control strategy is verified by a numerical simulation and a semi-physical simulation.