Kyoungsoo Ahn

Study on Coning Motion Test for Submerged Body

A submerged body is sensitive to changes in the roll moment because of the small restoring moment and moment of inertia. Thus, a method for predicting the roll-related hydrodynamic coefficients is important. This paper describes a deduction method for the hydrodynamic coefficients based on the results of a coning motion test. A resistance test, static drift test, and coning motion test were performed to obtain the coefficients in the towing tank of Seoul National University. The sum of the hydrodynamic force, inertial force, gravity, and buoyancy was measured in the coning motion test. The hydrodynamic force was deduced by subtracting the inertial force, gravity, and buoyancy from the measured force. The hydrodynamic coefficients were deduced using the regression method.

A study on the verification of collision avoidance support system in real voyages

The objectives of this paper are to describe the development results of the ship collision avoidance support system called HiCASS (Hyundai intelligent Collision Avoidance Support System) and present the real ship voyage test results of the system. This system automatically evaluates the risk of detected objects around ship using the information from AIS (Automatic Identification System), Radar ARPA (Automatic Radar Plotting Aid) and ENC (Electronic Navigational Chart). And if the risk is over the predefined level, it recommends the detour routes according to the COLREGs 1972 (International Regulations for Preventing Collisions at Sea 1972). Its usability has been verified in real round voyages between South Korea and Europe cooperating with HMM (Hyundai Merchant Marine). As a result, it is found that the system gives alarms at proper time and avoidable routes in complicated collision situations but the suggested collision avoidance routes are comparatively larger than the real action of officers.