TAGRA 2025

In this study, the parameters of the PI-type linear controller designed to regulate the liquid level in a coupled-tank system were optimized using three nature-inspired algorithms: Fata Morgana (FATA), Fox Optimization (FOX), and Moss Growth (MOSS). First, a nonlinear mathematical model of the coupled-tank system was derived to accurately represent the system dynamics. Subsequently, the transfer function corresponding to the required control configuration was obtained, and the PI controller gains, kp and ki, were optimized by using the FATA, FOX, and MOSS algorithms. For comparative assessment, the PI controller parameters were also tuned using the classical Ziegler–Nichols (Z–N) method, and all controllers were evaluated under two different step + time varying reference signal. The simulation results demonstrated that the controller parameters optimized by the FOX algorithm, have achieved superior reference tracking performance compared to those obtained using the FATA and MOSS techniques. Furthermore, the FOX-based controller has provided approximately 52% better reference tracking performance compared with the controller tuned using the Z–N method.