Robust Dynamic Actuator Failure Compensation Control of Nonlinear Systems via Cooperative Interaction Design

Area of Science:

• Control Systems Engineering
• Fuzzy Logic Systems
• Nonlinear Control Theory

Background:

• Uncertainty in control systems poses significant challenges, especially with actuator faults and malicious input signals.
• Takagi-Sugeno fuzzy systems offer a framework for modeling nonlinear dynamics but require robust control strategies.
• Existing fault-tolerant control methods may not adequately address combined uncertainties and malicious inputs.

Purpose of the Study:

• To develop a fault-tolerant resilient control (FTRC) strategy for uncertain Takagi-Sugeno fuzzy systems.
• To address additive actuator faults and malicious injections on control input signals.
• To ensure robust stability and performance in the presence of unknown bounded fault signals.

Main Methods:

• Modeling actuator faults and malicious injections as unknown bounded signals generated by finite- L2-gain dynamical systems.
• Introducing a fictitious dynamical system to capture compensation errors for unknown actuator faults.
• Proposing a novel actuator failure compensator (AFC) with dynamic feedback structures.
• Utilizing equivalence class and Lyapunov theories for stability analysis.

Main Results:

• A robust dynamic AFC-based fuzzy controller is designed to ensure asymptotic convergence of system states to zero.
• The proposed method guarantees good transient performance, outperforming existing FTRCs under unforeseen actuator faults.
• The effectiveness of the developed control strategy is validated through two illustrative examples.

Conclusions:

• The novel AFC-based fuzzy controller effectively handles uncertain Takagi-Sugeno fuzzy systems with actuator faults and malicious inputs.
• The cooperative design between virtual dynamical systems and closed-loop systems enhances compensation capabilities.
• The FTRC approach ensures both stability and improved transient performance, demonstrating practical applicability.