Web-based Remote Control System And Its Delay

The research of this thesis is based on the project "Intelligent Control Theory and Methodology Research of Networked Control Systems" which is funded by the National Science Foundation. A digital-servo remote control system is introduced as research platform. Firstly, network delay is tested preliminarily on the experiment platform. Secondly, using the improved Elman neural network, network delay is predicted and the foundations are laid for the research of network time-varying delay. The samples of the Elman network are the history records of the network delay which have been tested and saved. Finally, the delay part is processed for the system with short delay by Pade approximation. Then the Proportional and Derivative (PD) controller is used to compensate network delay of the system and dynamic performances is improved. For the system with long delay, Smith predictive control based on the improved Elman network compensatory model is studied. The improved Elman network is used to fit the modeling error of the Smith predictor and compensate the system. The results of the simulation experiments prove the feasibility of the proposed method by which the influence of network delay is reduced.