Output feedback fuzzy controller design with local nonlinear feedback laws for discrete-time nonlinear systems.

Area of Science:

• Control Systems Engineering
• Fuzzy Logic Systems
• Nonlinear System Dynamics

Background:

• Output feedback control is crucial for nonlinear discrete-time systems.
• Fuzzy systems with local nonlinear models present unique control challenges.
• Existing methods can be computationally intensive and require numerous fuzzy rules.

Purpose of the Study:

• To develop novel observer-based controllers for nonlinear discrete-time fuzzy systems.
• To address the H(infinity) dynamic output feedback (DOF) control problem.
• To reduce the complexity and computational burden of controller design.

Main Methods:

• Utilizing state and local model nonlinear function estimations.
• Proving a separation property for independent controller and observer design.
• Employing a two-step procedure with cone complementarity linearization algorithms for H(infinity) DOF control.

Main Results:

• Sufficient conditions for designing observer-based controllers are established.
• A separation property is proven for independent design of controllers and observers.
• A new DOF control scheme provides a convex condition for H(infinity) controller design when nonlinear functions are measurable.

Conclusions:

• The proposed methods enable the design of output feedback controllers with fewer fuzzy rules.
• The new approaches significantly reduce computational burden compared to existing methods.
• Effectiveness is demonstrated through numerical examples, facilitating practical controller implementation.