Finite-Time Prescribed Performance Control for Nonlinear Engineering Systems with Input Saturation

This paper investigates a finite-time prescribed performance control (PPC) problem for a class of nonlinear engineering systems subject to actuator input saturation. By introducing a performance transformation framework, the tracking error is constrained within predefined bounds with guaranteed finite-time convergence. To address the strict-feedback structure and input constraints simultaneously, a dynamic surface control (DSC) technique is employed to avoid the explosion of complexity. A novel saturation-compensated control law is constructed to ensure closed-loop stability without requiring the persistence of excitation or exact knowledge of system dynamics. Lyapunov-based analysis rigorously proves that all closed-loop signals are bounded and the prescribed performance is achieved within a finite time. The simulation results demonstrate the effectiveness of the proposed approach under actuator saturation, highlighting its applicability to constrained engineering process control systems.