Performance of Maneuver Control System due to Hydrodynamic Coefficient Changes, Case Study: War Ship of SIGMA Class

Abstract

The performance of ship maneuvering control system depends on hydrodynamic coefficient. The development of designing SIGMA class is cause of changing in the magnitude of this coefficient. This paper discusses the characteristics of the autopilot control system in various of hydrodynamic coefficients. The coefficient changes occur due to disturbance conditions from the ocean environment, or changes in ship dimensions. The ship's dimensional changes impact on gain of autopilot control system. Clark’s regression is used to calculate the hydrodynamics coefficients of ship. The method of design autopilot control systems uses a PID Zieger Nichols. The stability characteristics of system are analyzed in time and frequency domains. The value of hydrodynamics is linear due to change of length of ship, except the moment of inertia heave. The limit of response stability an autopilot system in tolerance of maximum is 110% of Lpp.