Underwater Navigation of an Autonomous Underwater Vehicle Using Range Measurements from a Fixed Reference Station

J. Ocean Eng. Technol. 2008;22(4):106-113.

Lee Pan-Mook,Jun Bong-Huan,Lim Yong-Kon

Ocean Exploration System Research Division MOERI KORDI,Ocean Exploration System Research Division MOERI KORDI,Ocean Exploration System Research Division MOERI KORDI

고정기준점에 대한 거리측정 신호를 이용하는 자율무인잠수정의 수중항법

이판묵,전봉환,임용곤

한국해양연구원 해양시스템안전연구소 해양탐사장비연구사업단,한국해양연구원 해양시스템안전연구소 해양탐사장비연구사업단,한국해양연구원 해양시스템안전연구소 해양탐사장비연구사업단

Keywords: Underwater navigation, Range measurement, Observability, Autonomous underwater vehicle (AUV), Kalman filter

핵심용어: 수중항법, 거리측정, 가관측성, 자율무인잠수정, 칼만필터

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 constituted an extended Kalman filter for discrete-time implementation of the navigation algorithm. The autonomous underwater vehicle, lSiMl, 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 to estimation 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.