• 제어로봇시스템학회논문지
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• 제10권5호
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• pp.442-449
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• 2004

As underwater robotic vehicles (URVs) become attractive for more sophisticated underwater tasks, the demand of high performance in terms of accuracy and dexterity has been increased. An autonomous underwater robotic vehicle, ODIN (Omni-Directional Intelligent Navigator) was designed and built at the Autonomous Systems Laboratory of the University of Hawaii in 1991. Since 1991, various studies were conducted on ODIN and have contributed to the advancement in underwater robotics. Its refurbished model ODIN II was based on VxWorks in VMEbus. Recently, ODIN was born again as a PC based system, ODIN III with unique features such as new vehicle system software architecture with an objective-oriented concept, a graphical user interface, and an independent and modular structure using a Dynamic Linking Library (DLL) based on the Windows operating system. ODIN III software architecture offers an ideal environment where various studies for advanced URV technology can be conducted. This paper describes software architecture of ODIN III and presents initial experimental results of fine motion control on ODIN III.

• 제어로봇시스템학회논문지
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• 제8권12호
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• pp.1023-1030
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• 2002

Since the dynamics of autonomous underwater vehicles (AUVs) are highly nonlinear and their hydrodynamic coefficients vary with different vehicle's operating conditions, high performance control systems of AUVs are needed to have the capacities of teaming and adapting to the variations of the vehicle's dynamics. In this paper, a linearly parameterized neural network (LPNN) is used to approximate the uncertainties of the vehicle dynamics, where the basis function vector of the network is constructed according to the vehicle's physical properties. The network's reconstruction errors and the disturbances in the vehicle dynamics are assumed be bounded although the bound may be unknown. To attenuate this unknown bounded uncertainty, a certain estimation scheme for this unknown bound is introduced combined with a sliding mode scheme. The proposed controller is proven to guarantee that all signals in the closed-loop system are uniformly ultimately bounded (UUB). Numerical simulation studies are performed to illustrate the effectiveness of the proposed control scheme.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1060-1065
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• 2005

An Independent Administrative Corporation Japan Agency for Marine-Earth Science and Technology (JAMSTEC) is developing light-and-small Autonomous Underwater Vehicles (AUV)$^{1)}$, named 'MR-X1' (Marine Robot Experimental 1), which can cruise, investigate and observe by itself without human's help. In this paper, we consider the motion control problem of 'MR-X1' and derive a controller. Since the dynamic property of 'MR-X1' is changed by the influence of the speed, the mathematical model of 'MR-X1' becomes the nonlinear model. In order to design a controller for 'MR-X1', we generally apply nonlinear control theories or linear control theories with some constant speed situation. If we design a controller by applying Linear Quadratic (LQ) optimal control theory, the obtained controller only compensates t e optimality at the designed speed situation, and does not compensate the stability at another speed situations. This paper proposes a controller design method using Linear Matrix Inequalities (LMIs)$^{2),3),4)}$, which can adapt the speed variation of 'MR-X1'. And examples of numerical analysis using our designed controller are shown.

• Ocean Systems Engineering
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• 제2권2호
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• pp.83-97
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• 2012

In the present work, design procedure and computer simulation of an AUV are documented briefly. The design procedure containing the design of propulsion system and CFD simulation of hydrodynamics behavior of the hull leads to achieve an optimum mechanical performance of AUV system. After designing, a comprehensive one dimensional model including motor, propeller, and AUV hull behavior simulates the whole dynamics of AUV system. In this design, to select the optimum AUV hull, several noses and tails are examined by CFD tools and the brushless motor is selected based on the first order model of DC electrical motor. By calculating thrust and velocity in functional point, OpenProp as a tool to select the optimum propeller is applied and the characteristics of appropriate propeller are determined. Finally, a computer program is developed to simulate the interaction between different components of AUV. The simulation leads to determine the initial acceleration, final velocity, and angular velocity of electrical motor and propeller. Results show the final AUV performance point is in the maximum efficiency regions of DC electrical motor and propeller.

• 한국해양공학회지
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• 제29권6호
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• pp.488-498
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• 2015

This paper presents the dynamic model of an AUV called HW200 for underwater surveillance. The mathematical model of HW200 is briefly introduced, considering its shape. The maneuvering coefficients were initially estimated using empirical formulas and a database of vehicles with similar shapes. A motion simulator, based on Simulink of Mathworks, was developed to evaluate the mathematical model of the vehicle and to tune the maneuvering coefficients. The parameters were finely tuned by comparing the experimental results and simulated responses generated with the simulator by applying the same control inputs as the experiment. The velocity of HW200 in the tuning process was fixed at a constant forward speed of 1.83 m/s. Simulations with variable speed commands were conducted, and the results showed good consistency in the motion response, attitude, and velocity of the vehicle, which were similar to those of the experiment even under the speed variation. This paper also discusses the feasibility of its application to a model-based integrated navigation system (INS) using the auxiliary information on the velocities generated by the model.

• 로봇학회논문지
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• 제18권1호
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• pp.53-58
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• 2023

In general, in order to operate an autonomous underwater vehicle (AUV) in an underwater environment, a navigation system such as a Doppler Log (DVL) using a Doppler phenomenon of ultrasonic waves is used for speed and direction estimation. However, most of the ultrasonic sensors in underwater is large for long-distance sensing and the cost is very high. In this study, not only canal neuromast on the fish's lateral lines but also superficial neuromast are studied on the simulation to obtain pressure values for each pressure sensor, and the obtained pressure data is supervised using spherical CNN. To this end, through supervised learning using pressure data obtained from a pressure sensor attached to an underwater vehicle, we can estimate the speed and angle of the underwater vehicle in a quasi-static underwater environment and propose a method for a non-ultrasonic based navigation system.

• 전자공학회논문지
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• 제49권11호
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• pp.103-109
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• 2012

논문에서는 천해역에서 운용가능한 소형의 자율무인잠수정 "BOTO"의 개발과 실해역 자율주행 성능시험에 관한 내용을 다룬다. BOTO의 개발을 위해 6자유도 운동방정식을 이용하여 시뮬레이션을 수행하였으며, 시뮬레이션 결과를 바탕으로 소형 자율무인잠수정을 개발하였다. 시뮬레이션에 사용되는 운동모델의 계수와 주행성능을 확인하기 위해 회류수조에서 저항계수 측정 시험도 수행하였다. 운동모델을 기반으로 무인잠수정의 선회반경 시뮬레이션과 수평면에서의 경로추종을 위한 알고리즘을 적용하여 시뮬레이션을 수행하였고, 설계된 제어기를 이용하여 실해역 자율주행시험을 수행하였다. 실해역 자율주행시험은 선회반경 측정시험과 경로점 추종시험을 실시하였으며, 실해역에서 목표 경로점을 잘 추종하는 것을 확인하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.211-224
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• 2019

This paper deals with a nonlinear controller based on saturation functions with variable parameters for set-point regulation and trajectory tracking control of an Autonomous Underwater Vehicle (AUV). In many cases, saturation functions with constant parameters are used to limit the input signals generated by a classical PD (Proportional-Derivative) controller to avoid damaging the actuators; however this abrupt bounded harms the performance of the controller. We, therefore, propose to replace the conventional saturation function, with constant parameters, by a saturation function with variable parameters to limit the signals of a PD controller, which is the base of the nonlinear PD with gravitational/buoyancy compensation and the nonlinear PD + controllers that we propose in this paper. Consequently, the mathematical model is obtained, considering the featuring operation of the underwater vehicle LIRMIA 2, to do the stability analysis of the closed-loop system with the proposed nonlinear controllers using the Lyapunov arguments. The experimental results show the performance of an AUV (LIRMIA 2) for the depth control problems in the case of set-point regulation and trajectory tracking control.

• 한국군사과학기술학회지
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• 제17권6호
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• pp.751-763
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• 2014

The paper is written to determine the optimal search pattern through search effects assessment on underwater targets. 5 types of search patterns are introduced such as, M-type pattern, W-type pattern, rectangular pattern, 4-type pattern and square pattern, In addition, Operational effectiveness analysis model is developed to obtain the optimum search pattern. The algorithms and mathematical models are also suggested to analyze the required search times, AUV's movement patterns, moving distances, overlapping areas and so on.

• 한국정보통신학회논문지
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• 제24권8호
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• pp.1077-1085
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• 2020

부설된 기뢰를 소해하기 위해 기뢰매설 예상구역에 대한 탐색을 수행한다. 이 때 기뢰탐색은 기뢰의 위험성, 아군의 안정성 등을 고려하여 자율무인잠수정을 이용한다. 매설된 기뢰를 식별하기 위한 소나시스템은 측면주사소나, 합성개구소나 등을 탑재한다. 본 논문은 측면주사소나 특성에 따른 기뢰탐색효과도 분석에 대해 기술한다. 각 측면주사소나의 특성을 바탕으로 음향조사역 및 인식확률을 모델링 하였고, AUV의 주행패턴에 따라 분석을 수행하였다. AUV의 주행패턴은 측면주사소나 음영구역의 유무에 따라 3가지 탐색패턴을 정의하였다. 분석결과는 각 탐색패턴 마다 탐지시간, 탐지확률을 도출하고 최종적으로 측면주사소나 음영구역의 유무에 따른 탐색 향상도를 도출하였다.