UUV(수중로봇)의 소개와 요소기술

22kc

Failure Detection of Multi-Sensor Navigation System

This study is devote to developing navigation filter for detecting sensor failure in multi-sensor navigation system. In multi-sensor navigation system, Kalman filter is generally used to fuse data of each sensors. Sensor failure is fatal in case that the sensor is used as external measurement of Kalman filter therefore detection and recovery of sensor failure is one the important feature of navigation filter. Generally each sensors have its specific feature in measuring navigational information. Fuzzy theory is proposed to detect external sensor failure and provide valid external measurement to Kalman filter avoiding filter divergence and instability. This idea is applied to Autonomous Underwater Vehicle(AUV) which has two navigation sensor i. e self contained inertial sensor and acoustic external sensor. 2 dimensional simulation result shows acceptable failure detection and recover

이산 슬라이딩 모드 제어 및 자율무인잠수정에의 응용

학위논문(박사) - 한국과학기술원 : 기계공학과, 1998.2, [ x, 125 p. ]This thesis presents a discrete-time quasi-sliding mode controller of SIMO systems with parameter uncertainties and long sampling interval based on variable structure system. Although conventional sliding mode control techniques are robust to system uncertainties, the sliding control system reveals chattering phenomenon and even makes the system unstable when the system has long sampling interval. The discrete quasi-sliding mode control system is designed to track the desired path on the basis of a Lyapunov function, and sufficient conditions of the switching gain are given to make the discrete system stable. Each component of the switching gain can be determined separately one another. The switching region is variable according to the product of the bounds of uncertainty and the amplitude of the trajectory. The controller is robust to the uncertainties, and the reaching condition of the control system is satisfied for any initial condition. This control law is a generalized form of the discrete quasi-sliding mode control and reduces the chattering problem considerably. This thesis also points out that the VSS type self-tuning controller of Furuta``s method can be improved by modifying the sector with separate gains and with equivalent control algorithm. The control system is stable in the outside of the sector and ultimately bounded in the inside of the sector. The proposed VSS type self-tuning controller prevents the estimated parameters from the fluctuation which can occur during the parameter adaptation. This controller with reduced switching sector is actually applicable to the tracking control of discrete systems in the presence of parameter uncertainties. The dynamic characteristic of an autonomous underwater vehicle is introduced and a model is derived for the AUV``s motion control in vertical plane. Depth keeping control and contouring control are performed for a numerical model of AUV with full nonlinear equations of motion to verify the effectiven...한국과학기술원 : 기계공학과

Transverse vibration of rectangular plates having circular holes

학위논문(석사) - 한국과학기술원 : 기계공학과, 1985.2, [ [ix], 61 p. ]한국과학기술원 : 기계공학과

Deep-sea floor exploration in the East Sea using ROV HEMIRE

국내 심해 저서환경의 접근 한계로 서식생물과 인근환경 연구를 위한 정밀채집이 불가능하였으나, 6,000 미터급 심해 무인잠수정 해미래의 개발로 가능성이 열렸다. 활용가능성 확인을 위해, 2015년 6월에 2주간 동해에서 연구선 온누리호와 무인잠수정 해미래를 이용하여 울릉분지와 후포퇴 사면의 8개 정점에서 심해 종합해양연구를 국내최초로 수행하였다. 수심 범위가 194~2,080m인 조사해역에서 총 10회 잠수를 수행하였고, 잠수시간은 운용조건에 따라 약 1~6시간 소요되었다. 조사 결과, 1) 주요 심해 해저면의 실제 영상, 2) 주요 수산자원인 홍게류의 서식밀도 및 미기록 생물종을 포함한 심해생물상 자료, 3) 해저협곡의 경사면 등 특이 지형 확인, 4) 압력주상채니기를 이용한 퇴적물 주상시료 채집, 5) 육상폐기물 해양 투기현황을 확인 및 획득하였다. 본 탐사결과 심해 저서환경 및 생물의 직접관찰 및 채집이 가능함을 확인하였다. HEMIRE is a 6,000-meter-class remotely operated vehicle (ROV) that has been developed for observation and sampling of objects of interest on the deep seabed. We first carried out deep-seabed exploration around the slopes of the Hupo Bank and the Ulleung Basin in the East Sea in June 2015. Over two weeks, a total of 10 dives were made from a support ship, the R/V Onnuri, at eight stations with water depth ranging between 194 and 2,080 m. The dive times ranged from 1 to 6 hours, depending on the operating conditions. We obtained the following results: 1) video images of the deep seafloor; 2) red snow crab density data (a major fishery resource) and inventories of deep-sea fauna, including an unrecorded organism; 3) specific topographies such as canyons slopes; 4) an undisturbed sediment core obtained using a push corer; and 5) observations of the seabed surface covered with discarded anthropogenic waste material.22Nkc

Development and Tank Test of an AutonomousUnderwater Vehicle 'ISiMI'

Maritime and Ocean Engineering Research Institute (MOERI), a branch of KORDI, has designed and manufactured a model of an autonomous underwater vehicle (AUV) named ISiMI (Integrated Submergible for Intelligent Mission Implementation). ISiMI is an AUV platform to satisfy the various needs of experimental test required for development of challenging technologies newly investigated in the field of underwater robot; control and navigational algorithms and software architectures. The main design goal of ISiMI AUV is downsizing which will reduce substantially the operating cost compared to other vehicles previously developed in KORDI such as VORAM or DUSAUV. As a result of design and manufacturing process, ISiMI is implemented to be 1.2 m in length, 0.17 m in diameter and weigh 20 kg in air. A series of tank test is conducted to verify the basic functions of ISiMI in the Ocean Engineering Basin of MOERI, which includes manual control with R/F link, auto depth, auto heading control and a final approach control for underwater docking. This paper describes the implementation of ISiMI system and the experimental results to verify the function of ISiMI as a test-bed AUV platform