거리-위상 계측용 초음파 신호를 이용한 수중복합항법시스템

Abstract

This paper presents an integrated navigation system for autonomous underwater vehicles with acoustic range-phase measurement. The integrated navigation system is based on a strap-down inertial measurement unit (IMU), where auxiliary navigation sensors are two range sonars for range-phase measurement, a Doppler velocity log (DVL), a magnetic compass and a depth sensor. The main idea of the paper is to improve the performance of the IMU-DVL navigation system by introducing additional range-phase information. The range-phase measurements can measure the distance and the incident angle from a reference transponder on an underwater station. The range-phase measurements are modeled to improve the navigation algorithm, which could provide valuable information for the IMU-DVL navigation to reduce estimation error, especially when the DVL cannot detect the bottom reflection. Simulation was conducted with the 6-d.o.f. nonlinear numerical model of an AUV in lawn-mowing survey mode at tidal flow, where the bottom reflected DVL information is unavailable. Simulations illustrate the effectiveness of the integrated navigation system assisted by the additional range measurements.