POSITION CONTROL OF HYDRAULIC SERVO CYLINDER FOR WAVE CHANNEL

Abstract

This study aims to achieve position control of the hydraulic cylinder for generating a regular waveform for tsunami, flood, and coastal structure interaction studies, and to measure the generated waveform in real time to determine its conformity to the desired shape. Today, wave channel systems safeguard aquatic ecosystems and play a crucial role in understanding and mitigating natural disasters, particularly in tsunami-prone areas. The wavemaker system in the wave channel is driven by a doubleacting hydraulic servo cylinder. A black-box approach is chosen for model identification, validated with real measurement data. PI parameters were initially determined using the Ziegler-Nichols method and later optimized in MATLAB using the PID Tuner and Genetic Algorithm (GA). The optimized PI parameters Kp and Kiwere found [0.2989 0.0023] for GA, compared to [0.2475, 0.14] for Ziegler-Nichols, and [0.23023 0.058609] for MATLAB/PID Tuner. Real-time wave measurements were recorded with a LabVIEW-based graphical interface. The step and sinusoidal responses of the hydraulic system were analyzed using three methods for determining PI parameters. GA-optimized PI achieved the best results, with ITAE improvements of 74.82% and 69.50%, RMSE improvements of 2.15% and 3.69%, and MAE improvements of 47.02% and 49.30% compared to Ziegler-Nichols and MATLAB/PID Tuner, respectively.