Control Of Bilateral Teleoperating System Under DoS Attack

In a teleoperating system,signals are transmitted through communication channels,so the system may be subject to Denial of Service(DoS)attack,which affects the performance of the teleoperating system and even causes system instability.When the signal is transmitted over a long distance,the communication channel has time delay,and the signal with time delay will produce error,resulting in system instability.Moreover,the model parameters of master and slave manipulators in the teleoperation system are uncertain,which will also affect the performance of the teleoperation system.At the same time,during the operation of the system,both master and slave manipulators may be subject to unknown external disturbances,which will affect the performance of the teleoperation system,and even cause instability of the teleoperation system.In this paper,the stability of teleoperating system under DoS attack is studied,and the time delay,uncertainty of model parameters and external disturbance of teleoperating system are considered.Based on the event triggering mechanism and using the position error structure,different controllers are designed according to the teleoperation system under different conditions,so that the system can be stable and have good performance.The main research contents of this paper are as follows:(1)This paper studies the stability of the teleoperating system under DoS attack in the ideal state,and designs the controller based on the event trigger mechanism,so that the teleoperating system can remain stable under DoS attack under both weak feedback and strong feedback.(2)Considering the time-delay and uncertainty of model parameters,the stability of teleoperating system under DoS attack is studied.The model parameters of the manipulator were estimated by the adaptive law,and the controller was designed based on event triggering and position error structure.The simulation results show that the controller can make the teleoperation system with time delay and uncertain model parameters stable under DoS attack,and the system has good tracking performance.(3)The stability problems of teleoperating system under DoS attack with constant or time-varying time delay,model parameter uncertainty and external disturbance in communication channels are studied respectively.Considering that the reference signal could not be excited continuously,the adaptive law was improved to estimate the uncertain part of the model parameters of the manipulator and to compensate the disturbance of the controller.The controller with disturbance compensation is designed based on event trigger,and the validity of the controller is proved by theory,and the validity of the controller is verified by numerical simulation.