자율무인잠수정의 해저면 초기위치 보정에 관한 연구

Abstract

This paper presents a calibration method to correct the initial position error of an autonomous underwater vehicle at sea floor. AUVs have an inertial navigation system assisted with auxiliary sensors, such as Doppler velocity log, and/or acoustic positioning systems. Since navigation systems show drift in position without the bottom reflection of DVL, APS is needed to set initial position. The main concept of the calibration method is this: When the AUV arrives near sea floor, the vehicle horizontally moves around in circular mode, while the USBL transceiver installed on surface vessel gathers the AUVs position. After acquiring one data set, a curve fitting method is adopted to find the center of the AUVs circular motion, which is transferred to the AUV via acoustic telemetry modem. The proposed method could reduce the intrinsic position error of the USBL and it is robust to the AUV motion caused by time delay of ATM. Monte Carlo simulation was conducted to verify the performance of the proposed calibration method.