Message Scheduling Based on Fuzzy Feedback in Networked Control Systems

Considering the error and error difference of sys- tem response,a fuzzy feedback scheduler that shares commu- nication net is designed with the bandwidth constraints.A scheduling algorithm of the scheduler,namely fuzzy maximum first(FMF),can schedule dynamically the priority of network message.Furthermore,a normalizable criterion of the quality of control(QoC),which can estimate the overall performance of networked control systems,is also defined.By this criterion three different scheduling algorithms with different stochastic delay series are compared with respectively.Finally,the results of simulation highlight that the proposed scheduling algorithm can optimize the performance of control loop and is more flexible than other algorithms in uncertain running conditions.