Practical prescribed-time output tracking control of uncertain nonaffine systems with input saturation based on time...

Area of Science:

• Control Systems Engineering
• Aerospace Engineering
• Nonlinear Control Theory

Background:

• Active disturbance rejection control (ADRC) is crucial for system adaptability.
• Uncertain nonaffine systems with input saturation pose significant control challenges.
• Prescribed-time control offers finite-time convergence within a user-defined settling time.

Purpose of the Study:

• To extend active disturbance rejection control to uncertain nonaffine systems with input saturation.
• To achieve practical prescribed-time (PPT) tracking control.
• To develop a robust control strategy that addresses nonaffine dynamics and input constraints.

Main Methods:

• Design of a practical prescribed-time (PPT) nonlinear extended state observer (NLESO) based on time base generators (TBG).
• Development of a TBG-based saturation control law utilizing PPT NLESO outputs.
• Mathematical proof of local PPT convergence for the closed-loop system under input saturation.

Main Results:

• The proposed PPT NLESO effectively estimates states and uncertainties while suppressing peaking.
• The TBG-based control law achieves PPT output tracking for nonaffine systems with saturation.
• Numerical and semi-physical simulations on an F-16 aircraft validate the method's efficacy and superiority.

Conclusions:

• The developed control strategy enhances adaptability for uncertain nonaffine systems with input saturation.
• The method guarantees practical prescribed-time convergence, driving tracking errors to a small neighborhood.
• The approach demonstrates significant potential for real-world applications, particularly in aerospace control systems.