Adaptive Decentralized Control for Interconnected Time-Delay Uncertain Nonlinear Systems With Different Unknown...

Area of Science:

• Control Engineering
• Nonlinear System Dynamics
• Systems Theory

Background:

• Interconnected nonlinear systems with time delays present significant control challenges.
• Unknown control directions and asymmetric time-varying constraints complicate controller design.
• Existing methods often require prior knowledge of control gains or are overly conservative.

Purpose of the Study:

• To develop an adaptive decentralized control strategy for uncertain nonlinear systems with time delays.
• To address unknown control directions and deferred asymmetric time-varying full-state constraints.
• To overcome limitations of existing integral barrier Lyapunov functions.

Main Methods:

• Construction of a novel time-varying asymmetric integral barrier Lyapunov function (TVAIBLF).
• Introduction of a shifting function to handle deferred state constraints.
• Application of the backstepping method combined with Nussbaum-type functions.

Main Results:

• The proposed TVAIBLF reduces conservatism compared to constant or symmetric IBLFs.
• The control strategy effectively handles unknown control directions and deferred asymmetric constraints.
• All signals in the closed-loop system are guaranteed to be bounded.
• Transform errors asymptotically converge to zero.

Conclusions:

• The developed adaptive decentralized control strategy is effective for the targeted complex systems.
• The method offers improved performance and broader applicability by avoiding prior gain knowledge.
• Simulation results validate the proposed control strategy's effectiveness.