부산대학교 도서관

Offshore platforms often endure a variety of continuous marine loads, each capable of inducing vibrations that pose risks, such as structural damage, personnel discomfort, fatigue, and safety hazards. Therefore, active vibration control emerges as a cornerstone in ocean platform engineering. This study focuses on addressing the problem of wave-induced vibration suppression using fuzzy sampled-data control techniques. Initially, a Takagi–Sugeno fuzzy dynamic model of offshore structures is developed by taking into account time-varying perturbations in natural frequency and damping ratio of the dominant vibration mode and unmodeled dynamics induced by other modes of structure. Then, using the looped functional method, several sufficient conditions are obtained to ensure the asymptotic stability of the closed-loop system. Based on these conditions, an algorithm is devised to compute suitable control gains in terms of linear matrix inequalities. Finally, extensive simulations demonstrate the efficacy of the proposed sampled-data fuzzy controller. Not only does it exhibit robustness against parametric perturbations in offshore structures, but it also yields significant reductions in wave-induced responses, thus fortifying the platform’s safety and resilience.