고정기준점에 대한 거리측정 신호를 이용하는 자율무인잠수정의 수중항법

Abstract

This paper presents an underwater navigation system based on range measurements from a known reference station fixed on the sea bottom or floated at surface with a buoy, for which the system is extended to 3-dimensional coordinates. We formulated a state equation in polar coordinates and constitutedan extended Kalman filter for discrete-time implementation of the navigation algorithm. The autonomous underwater vehicle, ISiMI, cruising with a constant speed can estimate its trajectory using just range measurements and additional depth, heading, and pitch sensors. Simulation studies were performed to evaluate the underwater navigation of the maneuvering AUV with range measurements. We modulated the sample rate of range measurements to evaluate the effect of the update rate, and changed the initial position error of the AUV to check the robustness toestimation errors. Simulation results illustrates that the extended navigation system provides convergence of the state estimates. The navigation system was conditionally stable when it had initial position errors.