Guaranteed Cost Controller With Output Prediction For The Multi-rate Networked Control Systems

The multi-rate networked control system refers that the sampling period of sensors,controllers and actuators are different from each other,which means the system has more than two sampling periods.In fact,a lower frequency is taken for the sensor node in the networked control system to decrease the network overload,while the other higher frequency is taken for the control node to guarantee the read-time control.Besides,it is also necessary to establish a multi-rate model for the multi-input multi-output networked control system in which the signals with various properties may require different sampling period.In the case of multi-rate sampling,due to the uncertainty of data transmission on the network and the diversity of sampling period,it has become very complicated for modelling of multi-rate control system.This research focuses on modeling and guaranteed cost controller designing of multi-rate networked control system.Firstly,for the multi-rate networked control system with a short delay,a guaranteed cost controller based on the normal model is proposed.In order to make control actions of the multi-rate networked control system more effective,a prediction equation is designed to predict more outputs during a sensor sampling period,and the control actions are calculated based on the prediction,what's more,a guaranteed cost controller is designed and the stability analysis is given.For the single side and both side networked control system,the guaranteed cost controller is designed respectively and the stability analysis is demonstrated.For a spacecraft attitude control system with multi-channel data transmission and the proposed MIMO discrete model,a guaranteed cost controller is put forward based on the dynamic output feedback with output prediction,and the stability of closed system is proved.The simulation results illustrate the faster response ability of the proposed multi-rate networked control method.