Analysis and Synthesis of Memory-Based Fuzzy Sliding Mode Controllers

Area of Science:

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

Background:

• Takagi-Sugeno fuzzy systems are widely used for modeling complex nonlinear dynamics.
• Sliding mode control (SMC) offers robustness against uncertainties but can suffer from chattering.
• Conventional SMC often utilizes memoryless sliding surfaces, limiting performance in systems with state delays.

Purpose of the Study:

• To develop a robust and adaptive sliding mode control strategy for Takagi-Sugeno fuzzy systems with matched uncertainties.
• To introduce a novel memory-based sliding surface incorporating both current and delayed states.
• To enhance system stability and transient performance while mitigating chattering.

Main Methods:

• Design of a memory-based sliding surface integrating current and delayed system states.
• Development of robust and adaptive fuzzy sliding mode controllers based on the proposed sliding surface.
• Introduction of continuous sliding mode controllers to minimize undesirable chattering effects.
• Stability analysis to ensure asymptotic stability of the closed-loop system.

Main Results:

• The proposed memory-based sliding surface enables the system to reach the sliding surface.
• The designed controllers guarantee asymptotic stability for the closed-loop Takagi-Sugeno fuzzy system.
• Continuous sliding mode controllers effectively reduce chattering phenomena.
• Experimental validation on a ball and beam system demonstrates significant improvements in transient performance.

Conclusions:

• The memory-based sliding surface approach offers superior control performance for Takagi-Sugeno fuzzy systems compared to conventional methods.
• The proposed robust and adaptive controllers ensure stability and enhance transient response, making them effective for uncertain systems.
• The developed techniques provide a valuable framework for advanced control design in systems with time delays and uncertainties.