• Proceedings of the IEEK Conference
• /
• 2002.06e
• /
• pp.153-156
• /
• 2002

The remotely operated underwater robotic vehicle system has been required to inspect some objects such as baffle former bolts and remove foreign objects in reactor vessel of nuclear power plant. In this paper, we have designed the remotely operated underwater robotic vehicle system that includes a long reach arm that is composed of 4 joints to remove foreign objects in a narrow space, a camera for visual test, instrument sensors for vehicle positioning, 4 thrusters for underwater navigation of vehicle, and supervisory control system implemented with industrial PC that includes robot simulator that has the functions of real time visualization, robot work planning and etc.

• Journal of Ocean Engineering and Technology
• /
• v.3 no.2
• /
• pp.551-551
• /
• 1989

In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

• Journal of Ocean Engineering and Technology
• /
• v.3 no.2
• /
• pp.51-58
• /
• 1989

In general, a remotely operated vehicle(ROV) operates at deep sea. The control system of ROV is composed of two local loops; the first loop placed on the surface vessel monitors and manipulates the attitude of the ROV using joystick, and the second part on the ROV automatically controls thrusters and acquires positional data. This paper presents a position control simulation of a ROV using an adaptive controller and discusses the control effects of two different conditions. The design of an adaptive control system is obtained by the application of a self-tuning controller with the minimization of an appropriate cost function. The parameters of the control system are estimated by a recursive least square method(RLS). In the simulation, a Runge-Kutta method is used for the numerical integration and the generated outputs are obtained by adding measurement errors. Additionally, this paper discusses the mathematical modelling of a ROV and make a survey of control systems.

• The Journal of Korea Robotics Society
• /
• v.18 no.1
• /
• pp.82-87
• /
• 2023

This paper proposes a disturbance observer-based control for 6-DOF remotely operated underwater vehicles with model uncertainties. The sum of external disturbance and the forces generated from model parameters except for the inertial matrix of the hydrodynamic model is defined as a lumped disturbance in this paper. Then, the lumped disturbance caused by model uncertainties and the external forces is estimated using the disturbance observer. Fortunately, the disturbance observer is constructed as a linear form because all the elements of the inertial matrix of the hydrodynamic model are constants. To verify the proposed control scheme, we show that the actual lumped disturbance is similar to the estimated lumped disturbance obtained by the disturbance observer. Finally, the position tracking performance in the disturbance environment is confirmed through the comparative study with a traditional inverse dynamics PD controller.

• The Journal of Korea Robotics Society
• /
• v.19 no.1
• /
• pp.8-15
• /
• 2024

This paper proposes a linear model predictive control of 6-DOF remotely operated underwater vehicles using nonlinear robust internal-loop compensator (NRIC). First, we design a integrator embedded linear model prediction controller for a linear nominal model, and then let the real model follow the values calculated through forward dynamics. This work is carried out through an NRIC and in this process, modeling errors and external disturbance are compensated. This concept is similar to disturbance observer-based control, but it has the difference that H_∞ optimality is guaranteed. Finally, tracking results at trajectory containing the velocity discontinuity point and the position tracking performance in the disturbance environment is confirmed through the comparative study with a traditional inverse dynamics PD controller.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.32 no.11
• /
• pp.997-1002
• /
• 2008

This paper is mainly concerned with the development of a remotely operated vehicle for investigation of the coastal sea. For this, we have designed and constructed a vehicle entitled KMU-ROV(Korea Maritime University Remotely Operated Vehicle), for purpose of investigation mission under 50(m) of the sea surface. We have designed six independent waterproof actuators and the housing of the controller for underwater operation. For six degree-of-freedom motion, we have analyzed the dynamics of the KMU-ROV and have designed a new composition of six actuators including the driving system. For motion control, we have composed a concurrent velocity control algorithm for controlling the speed of all the actuating motors. The control system for the KMU-ROV is composed of a master DSP controller, DSP controller for the motor control and various sensors. We composed the PID control algorithm and a network system for controlling motors using the CAN communication. The performance of the KMU-ROV was presented by testing the developed control algorithm and control system under the water.

• Journal of the Korean Society of Industry Convergence
• /
• v.21 no.6
• /
• pp.389-394
• /
• 2018

Remotely operated vehicle(ROV) and autonomous underwater vehicle(AUV) have been used for underwater surveys, underwater exploration, resource harvesting, offshore plant maintenance and repair, and underwater construction. It is hard for people to work in the deep sea. Therefore, we need a vision control system of underwater submersible that can replace human eyes. However, many people have difficulty in developing a deep-sea image control system due to the deep sea special environment such as high pressure, brine, waterproofing and communication. In this paper, we will develop an Ethernet based remote image control system that can control the image mounted on ROV.

• Journal of Ocean Engineering and Technology
• /
• v.32 no.2
• /
• pp.131-137
• /
• 2018

In this paper, we propose an adaptive backstepping controller to control the exact position and orientation of a remotely operated underwater vehicle with parametric model uncertainty. To further improve the angular velocity control precision of each thruster, a phase locked loop (PLL) controller has been added to the backstepping controller. A comparison of two backstepping controllers with and without the PLL control loop has been performed using simulations and experiments. The test results showed that the tracking performance could be improved by using the PLL control loop in the proposed adaptive backstepping controller.

• Journal of Ocean Engineering and Technology
• /
• v.20 no.3 s.70
• /
• pp.7-14
• /
• 2006

This paper discusses the structural design and analysis of a 6,000 meters depth-rated capable deep-sea unmanned underwater vehicle (UUV) system. The UUV system is currently under development by Maritime and Ocean Engineering Research Institute(MOERI), Korea Ocean Research and Development Institute (KORDI). The UUV system is composed of three vehicles - a Remotely Operated Vehicle (ROV), an Autonomous Underwater Vehicle (AUV) and a Launcher - which include underwater equipment. The dry weight of the system exceeds 3 tons hence it is necessary to carry out the optimal design of structural system to ensure the minimum weight and sufficient space within the frame for the convenient use of the embedded equipments. In this paper, therefore, the structural design and analysis of the ROV and launcher frame system were carried out, using the optimizing process. The cylindrical pressure vessels for the ROV were designed to resist the extreme pressure of 600 bars, based on the finite element analysis. The collapse pressure for the cylindrical pressure vessels was also checked through a theoretical analysis.

• Journal of the Korean Society for Precision Engineering
• /
• v.26 no.5
• /
• pp.41-47
• /
• 2009