• Special Issue of the Society of Naval Architects of Korea
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• 2006.09a
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• pp.112-121
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• 2006

The vertical displacement of a ship on the basis of the sea level is an important parameter for its stability and control. To indicate the displacement on operating conditions, "draft marks" are carved on the hull of the ship in various ways. One of the methods is welding. The position, shape and size of the marks are specified on the shipbuilding rules by classification societies to be checked by shipbuilders. In most cases, high-skilled workers do the welding along the drawing for the marks and welding bead becomes the marks. But the inaccuracies due to human errors and high labor cost increase the needs for automating the work process of the draft marks. In the preceding work, an indoor robot was developed for automatic marking system on flat surfaces and the work proved that the robot welding was more effective and accurate than manual welding. However, many parts of the hull structure constructed at the outdoor are cowed shapes, which is beyond the capability of the robot developed for the indoor works on the flat surface. The marking on the curved steel surface requiring the 25m elevations is one of the main challenges to the conventional robots. In the present paper, the robot capable of climbing vertical curved steel surfaces and performing the welding at the marked position by effectively solving the problems mentioned earlier is presented.

• International Journal of CAD/CAM
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• v.6 no.1
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• pp.41-48
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• 2006

Nowadays major shipbuilding companies are trying to expand their business not only to shipbuilding but to offshore projects as well. DSME is one of them. DSME is trying to set up a flexible design and construction environment for shipbuilding and offshore construction in a single shipyard. The shipbuilding and offshore projects, however, have their unique technology but they need to be designed and constructed in one site. To support this new requirement, DSME has developed an integrated CAD system for ship and offshore projects. In this integrated design environment, the designers can design commercial ships and offshore projects in a flexible manner. Concurrent design is very important for ship and offshore design. As compared to the complexity of the product, the design period is quite short. In effect, the design system for the ship and offshore project has to support concurrent design. One essential point of concurrent design environment is a product model based design system. DSME has developed and implemented the 3D product model concurrent design environment based on Tribon M3. Tribon is a widely used CAD system in shipbuilding area that is developed by Tribon Solutions. DSME has both customized the Tribon system and developed in-house application systems to support its own design and production procedures. All the design objects are modeled in one common database to support concurrent design and accurate production. The major in-house development focused on the modeling automation and automatic drawing generation. During the drawing generation process many of the additional production information are also extracted from the 3D product model. In addition, several applications and functionalities have been developed to apply the shipbuilding based Tribon M3 system to offshore projects. The development of shape nesting, tubular connection, isometric drawing, grating nesting systems are the typical.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.626-630
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• 2005

This paper presents a novel Intelligent-Welding-Carriage (IWC) for automation of curved block in shipbuilding. The curved block is usually used in both front and back side of the ship. In curved block root gap is big, $1{\sim}7$ [mm] and inclination, $0{\sim}30$ [deg]. Since available conventional carriage type is limited to use below root gap of 3 [mm], only manual welding is employed in curved block. To adopt an IWC in curved block, it requires control of the welding conditions, i.e., voltage, current and travel speed, with respect to root gap and inclination to achieve good welding quality. In this paper, an IWC is developed for automization of welding operation to accommodate gap and inclination. Kinematics model and dynamics using Lagrangian formulation of the manipulator is introduced. IWC utilizes a database to perform accurate welding. The database is programmed based on numerous experimental test results with respect to gap, inclination, material, travel speed, weaving condition, voltage, and current. Finally, experimental result using PID control is addressed for verify the trajectory tracking accuracy of end-effector.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.171-176
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• 2005

This paper presents a novel Intelligent-Welding-Carriage (IWC) for automation of curved block in shipbuilding. The curved block is usually used in both front and back side of the ship. In curved block root gap is big, 1-7 (mm) and inclination, 0-30 (deg). Since available conventional carriage type is limited to use below root gap of 3 (mm), only manual welding is employed in curved block. To adopt an IWC in curved block, it requires control of the welding conditions, i.e., voltage. current, weaving speed, dwell time and travel speed, with respect to root gap and inclination to achieve good welding qualify. In this paper, an IWC is developed for automization of welding operation to accommodate gap and inclination. Kinematics model and dynamics using Lagrangian formulation of the manipulator is introduced. IWC utilizes a database to perform accurate welding. The database is programmed based on numerous experimental test results with respect to gap, inclination, material, travel speed, weaving condition, voltage, and current. Finally, experimental result using PID control is addressed for verifying the trajectory tracking accuracy of end-effector.

• International Journal of Control, Automation, and Systems
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• v.4 no.2
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• pp.255-270
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• 2006

In this paper, a design method of nonlinear autopilot for ship-to-ship missiles is proposed. Ship-to-ship missiles have strongly coupled dynamics through roll, yaw, and pitch channel in comparison with general STT type missiles. Thus it becomes difficult to employ previous control design method directly since we should find three different solutions for each control fin deflection and should verify the stability for more complicated dynamics. In this study, we first propose a control loop structure for roll, yaw, and pitch autopilot which can determine the required angles of all three control fins. For yaw and pitch autopilot design, missile model is reduced to a minimum phase model by applying a singular perturbation like technique to the yaw and pitch dynamics. Based on this model, a multi-input multi-output (MIMO) nonlinear autopilot is designed. And the stability is analyzed considering roll influences on dynamic couplings of yaw and pitch channel as well as the aerodynamic couplings. Some additional issues on the autopilot implementation for these coupled missile dynamics are discussed. Lastly, 6-DOF (degree of freedom) numerical simulation results are presented to verify the proposed method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.174-178
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• 1999

Recently, the computer vision has been applied to many automation fields. Especially, this paper presents a maritime traffic detection system using computer vision since the high level information can be obtained using obtained area information. The high level informations are obtained such as speed, queueing length, queueing time, ship size, and ship kind. To get ship speed, the two detection lines are set on the predetermined screen position. The speed is obtained the passing time and the predetermined distance between the first and second detection line on the screen. Also, queueing length and time are gotten using screen position of ship. Furthermore, the size and kind of ship are calculated using the ship database and camera calibration data. This developed system contributes to reduce the traffic accidents on the coast. Futhermore, the more information can be extracted using obtained area information.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.4
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• pp.667-674
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• 2004

This thesis is about the Impressed Current Cathodic Protection (ICCP) control and monitoring system. which brings protection against the corrosion of the ship's hull in the sea environments. The ICCP system is composed of a power supply. anode. reference electrode and controller. AC sources from the ship's generator are converted to DC sources in terms of power supply, and a protection current is sent to ship's hull though anode. The controller fully senses whether or not the detected potential is within a range of protection of ship's hull and then it is automatically controlled to increase or decrease the amount of protective current to be sent to the anode. The monitoring system with RS 232/485 communication is also studied in order to check the normal state of the system at a long period. because an operator does not always watch over this system and thus the system cannot operate well because of his or her negligent management. Since the vessel always navigates in the sea. an characteristics experiment of the ICCP system is conducted by introducing various corrosive environmental factors such as velocity, resistivity, dissolved oxygen, PH, temperature and contamination degree. These results must be referred to when the ICCP system is set up. In short. the ICCP is a multi-system for use on ships and on land structures because it includes a safety device. It is suggested that this system can accomodate a ship's automation and will be very useful.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.208-216
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• 1999

Nowadays coustomer's needs for high surface quality steel sheet has greatly increased, so it is necessary to pay more attention to the roll grinding, texturing and handling. POSCO can acquire high surface quality roll and high productivity through World-first fully automated Roll Shop system which had been constructed '94.10.1∼'97.8.28 at Kwangyang Works. Roll Shop Automation System consists of Level-I, II, III control system and 23 automated machines. After the completion of the construction, the system started smoothy and keeps its operation with high productivity as expected. The installation of this system gave an epoch-making man power saving. This paper introduce its main facilities and operation.

• Journal of Fisheries and Marine Sciences Education
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• v.4 no.2
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• pp.101-108
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• 1992

This study is some parts, the contents on "Course of Power Machinery and of Automated-Ship Operation", of the results of the sixth curriculum, revision study for the fisheries high schools and merchant marine high schools. In this study, it was suggested that the existing name "the Course of Marine Engine" is revised to "the Course of Power Machinery" and "the Course of Automated-Ship Operation" is newly established. The purpose of the revision of the name to "the Course of Power Machinery" is to give the course a more flexible curriculum which enables the course to bring up not only sea duty marine engineers but also shore duty power engineers. Also, the purpose of the new establishment of "the Course of Automated-Ship Operation" is to bring up automated-ship operators. The necessities for automated-ship operator is derived from the process of ship automation to reduce the number of crew to cut down the expenses. The revised parts of the organization of the professional subjects exclusively related to "the Course of Power Machinery" and "the Course of Automated-Ship Operation" are summarised as follows; (l) The Automated-Ship are newly added. (2) The Sea Training, the Fisheries Law are Disused. (3) The Introduction to Ship, the Introduction to Marine Engine and the Introduction to Marine Communication are merged into the Introduction to Ship. (4) The name of the Marine Engine, the Shipping Business are revised to the Heat Engine, the Introduction to Shipping respectively. (5) M compulsory professional subjects, the Introduction to Fisheries is suggested for the fisheries high schools and the Introduction to Shipping is suggested for the merchant marine high schools.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.45-51
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• 2018

Autonomous ship has been sportlighted as a core technology for the maritime industry in Industry 4.0 era. Autonomous ship is expeected to improve the safety, reliability, efficiency and environment significantly. For the realization of the autonomous ship, the remote control of the ship is one of the core functionality in addition to the autonomous ship control functionality in a ship. In this paper, we address a autonomous ship control system based on remote control. This paper proposes a remote control autonomous system and standardized ship-to-shore remote control protocol with for open platform. Finally, we implemented the system and tested with a real experiments with the test ship in order to demonstrate the feasibility of the proposed remote control autonomous system.