Design of the Simulation Platform for Networked Control. Systems Based on DTHMM

摘要

In order to achieve the application of discrete-timehidden Markov model (DTHMM) in modeling and controllingthe networked control system (NCS) with the network-induceddelays in the forward channel, a simulation platform wasdesigned and implemented in this paper by using TrueTime 1.5,which is a Matlab/Simulink-based simulator. There were onenetwork module and four kernel modules (sensor, controller,actuator and interference nodes) on this simulation platform, andthe composition and the main Matlab codes of each module werepresented. On the simulation platform designed,the ExpectationMaximization (EM) algorithm was achieved to derive theparameters of the DTHMM and the Viterbi algorithm wasachieved to predict the controller-to-actuator delay (C-A delay)in the current sampling period. Based on the derived DTHMMand the predicted delays, a state-feedback controller to stabilizethe NCS was also implemented on the simulation platform andused to solve the linear matrix inequalities. Taking a dampedcompound pendulum as the plant in the NCS, after 500 samplingperiods the effectiveness of the modeling and controlling methodswas carried out, and demonstrated the efficiency and easyoperation of the simulation platform.