역시뮬레이션 기법을 이용한 무인잠수정의 운동성능 해석에 대한 연구

Abstract

An UUV (Unmanned Underwater Vehicle) is commonly used in hazardous fields such as oceanographic studies, sub-sea works, and military applications of ISR (Intelligence, Surveillance and Reconnaissance), ASW (Anti-Submarine Warfare) and MCM (Mine Countermeasure).

This dissertation mainly focuses on the development of a dynamic control system for the UUV equipped with three dedicated thrusters and a mass moving system. The dynamic control system is constructed based on the inverse simulation method which includes a mathematical model with the six degrees of freedom (6-DOF) consisted of linear and nonlinear hydrodynamic coefficients, which can be obtained from empirical formula, CFD (Computational Fluid Dynamics) and PMM (Planar Motion Mechanism) test.

To analyze the dynamic performance, the inverse simulation method based on inverse dynamics is utilized to calculate the input thrust force of three thrusters and the eligible distance of the mass moving system of the UUV under the specific trajectory and acceleration profiles developed in this dissertation.

Moreover, the evaluation on the proposed method has been carried out in terms of the effectiveness of thrust power consumption and the deviation from the desired speed, heading, pitch and depth. In order to analyze the dynamic performance of the UUV, the conventional simulation program also designed. The PID and Fuzzy-PID controller is applied after this complicated feedback system. The thruster dynamics and mass moving system is also incorporated in to the control system design. The performance analysis is performed in the navigation control by the operation concept that means specific predefined trajectory. The effectiveness of the control methods are demonstrated by simulation for a typical underwater mission. It is demonstrated numerically that the navigation system together with controller guides the vehicle to follow the desired trajectory which maintains the speed, heading, pitch and depth with a sufficient accuracy.