Suppression of Packet Losses and Disturbances in Networked Control Systems Based on Equivalent-Input-Disturbance...

Area of Science:

• Control Systems Engineering
• Networked Control Systems (NCS)
• Robotics

Background:

• Network-induced delays and packet losses significantly degrade the performance of networked control systems (NCS).
• Existing methods often struggle to simultaneously address disturbances and tracking requirements under uncertain network conditions.

Purpose of the Study:

• To develop a robust control strategy for NCS that effectively suppresses packet losses and exogenous disturbances.
• To enhance tracking performance while maintaining system stability in the presence of network-induced delays.

Main Methods:

• A two-loop feedback structure incorporating a local loop for disturbance suppression and a main loop for tracking.
• Design of a state observer and equivalent-input-disturbance (EID) estimator for prompt disturbance rejection.
• Utilizing linear matrix inequality (LMI) optimization for state-feedback gain design, embedding tracking specifications.

Main Results:

• The proposed method demonstrates effective suppression of packet losses and exogenous disturbances in NCS.
• Satisfactory tracking performance is achieved by integrating specifications into the LMI-based stability condition.
• Validation through a case study on a two-finger robot hand control system.

Conclusions:

• The presented method offers superior performance compared to existing approaches like Smith-EID and H∞ controllers.
• This approach provides a robust and effective solution for controlling NCS operating under challenging network conditions.