바람과 조류 중 선박의 crabbing motion에 관한 연구

Berthing and unberthing operation of a twin screw ship deserves special attentions in some cases. The speed of the ship is extremely low or even zero during berthing and unberthing. Crabbing is the ability of ship to move sideways without having a forward speed, so it can be applied to berthing and unberthing operation. Crabbing is induced by the use of combination of main propellers, rudders and side thrusters. In this study, 3 Degree-of-Freedom(DOF) motions such as surge, sway, and yaw are considered for crabbing motion simulation. The used modular mathematical model is expressed in terms of hull force, propeller force, rudder force, side thruster force and interaction force. Environmental loads such as wind and current is considered. Base on the equation of motion, crabbing motion is simulated.