Roll Reduction Control during Ship Turns Using Fin Stabilizers with PID Controller Based on Monte Carlo Optimization

Abstract

Fin stabilizers are designed to generate maximum anti-rolling moment to stabilize ship roll motion during ordinary straight navigation. However, they are usually turned off during ship turns as it may enlarge the roll and heel of the ship caused by the turns. This paper aims to explore the practicability of using fin stabilizers to reduce the roll and heel during ship turns with an improved PID controller based on Monte Carlo optimization. The mathematical models of ship motion, propulsive device, control equipment and wave disturbance are established. Based on the analysis of ship turning motion with and without fin stabilizers, an practical used improved PID is developed. To achieve the optimal anti-rolling effect, the controller parameters are optimized using Monte Carlo optimization. For comparison purpose, the control effect of the PID controller with control parameters obtained from Ziegler-Nichols approach is also given. Simulation results show that fin stabilizers are effective for ship roll control during ship turns with an improved PID controller based on Monte Carlo optimization.