• Title/Summary/Keyword: Ship attitude control

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Attitude control of foil-catamaran

  • Rhee, Key-Pyo;Lee, Gyoung-Jung;Lee, Sim-Yong
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.150-153
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    • 1995
  • In this paper the attitude control system is developed for longitudinal motion of Foil-Catamaran in regular waves with all-movable foils which attached to fore and after part of the ship and verified the system by theoretical calculation and model-tests. The linearized equations of motion of the ship is employed to apply the linear control theories, the PID control and the LQR. The strip method was used to calculate hydrodynamic coefficients and wave exciting forces of the demi hull, and unsteady hydrodynamic forces of foils are considered by using the result of Wu(1972). About 40-60% of motions is reduced in experiments. The control system described in this paper is able to extended to 6-DOF motions or control in irregular wave with trivial modification. And it is applicable to hull shape development for better seakeeping performance and to determine the size and the position of hydrofoils for the attitude control.

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ON-LINE DYNAMIC SENSING OF SHIP'S ATTITUDE BY USE OF A SERVO-TYPE ACCELEROMETER AND INCLINOMETERS

  • Tanaka, Shogo;Nishifuji, Seiji
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.162-165
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    • 1995
  • For an accurate on-line measurement of the ship's attitude the paper develops an intelligent sensing system which uses one servo-type accelerometer and two servo-type inclinometers appropriately located on the ship. By considering the dynamics of the servo-controlled rigid pendulums of the inclinometers, linear equations for the rolling and pitching of the ship are derived separately from each other. Moreover, one accelerometer is used for extracting the heaving signal. Through the introduction of linear dynamic models and the linear observation equations for the heaving, rolling and pitching, the on-line measurement of the three signals can be reduced to the state estimation of the linear dynamic systems. A bank of Kalman filters is adaptively used to achieve the on-line accurate state estimation and to overcome changes in parameters in the linear dynamic models.

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Backstepping and Partial Asymptotic Stabilization: Applications to Partial Attitude Control

  • Jammazi, Chaker
    • International Journal of Control, Automation, and Systems
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    • v.6 no.6
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    • pp.859-872
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    • 2008
  • In this paper, the problem of partial asymptotic stabilization of nonlinear control cascaded systems with integrators is considered. Unfortunately, many controllable control systems present an anomaly, which is the non complete stabilization via continuous pure-state feedback. This is due to Brockett necessary condition. In order to cope with this difficulty we propose in this work the partial asymptotic stabilization. For a given motion of a dynamical system, say x(t,$x_0,t_0$)=(y(t,$y_0,t_0$),z(t,$z_0,t_0$)), the partial stabilization is the qualitative behavior of the y-component of the motion(i.e., the asymptotic stabilization of the motion with respect to y) and the z-component converges, relative to the initial vector x($t_0$)=$x_0$=($y_0,z_0$). In this work we present new results for the adding integrators for partial asymptotic stabilization. Two applications are given to illustrate our theoretical result. The first problem treated is the partial attitude control of the rigid spacecraft with two controls. The second problem treated is the partial orientation of the underactuated ship.

System Identification and Pitch Control of a Planing Hull Ship with a Controllable Stern Intercepter (능동제어가 가능한 선미 인터셉터가 부착된 활주선형 선박의 시스템 식별과 자세 제어에 관한 연구)

  • Choi, Hujae;Park, Jongyong;Kim, Dongjin;Kim, Sunyoung;Lee, Jooho;Ahn, Jinhyeong;Kim, Nakwan
    • Journal of the Society of Naval Architects of Korea
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    • v.55 no.5
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    • pp.401-414
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    • 2018
  • Planing hull type ships are often equipped with interceptor or trim tab to improve the excessive trim angle which leads to poor resistance and sea keeping performances. The purpose of this study is to design a controller to control the attitude of the ship by controllable stern interceptor and validate the effectiveness of the attitude control by the towing tank test. Embedded controller, servo motor and controllable stern interceptor system were equipped with planing hull type model ship. Prior to designing the control algorithm, a model test was performed to identify the system dynamic model of the planing hull type ship including the stern interceptor. The matrix components of model were optimized by Genetic Algorithm. Using the identified model, PID controller which is a classical controller and sliding mode controller which is a nonlinear robust controller were designed. Gain tuning of the controllers and running simulation was conducted before the towing tank test. Inserting the designed control algorithm into the embedded controller of the model ship, the effectiveness of the active control of the stern interceptor was validated by towing tank test. In still water test with small disturbance, the sliding mode controller showed better performance of canceling the disturbance and the steady-state control performance than the PID controller.

Design of transfer alignment algorithm in ship of horizontal axis attitude motion (수평축 자세운동이 있는 배에서의 전달정렬 알고리즘 설계)

  • Song, Ki-Won;Jeon, Chang-Bae;Kim, Hyun-Baek;Yoo, Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.672-675
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    • 1996
  • This paper presents algorithm including Kalman filter for transfer alignment of velocity and quaternion matching method, when master inertial navigation system is a gimbled type and slave inertial navigation system is a strapdown type on a cruising ship which is naturally in motion of horizontal axis attitude. And relative attitudes are considered on a measurement equation for quaternion matching between master INS and slave INS.

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Design of Control Algorithm for Mass Driving Anti-Rolling System Considering Control Input Constraint (제어 입력포화를 고려한 횡동요 저감장치용 제어알고리듬 설계)

  • Moon, Seok-Jun;Lim, Chae-Wook;Lee, Hae-Jong
    • Journal of the Society of Naval Architects of Korea
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    • v.42 no.6 s.144
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    • pp.566-574
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    • 2005
  • Reduction of a ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargos as well as improving the comfort of the ride. A mass driving anti-rolling system (MO-ARS) might be one candidate of several systems against the ship's rolling. As the movable range of the mass on the ship is finite, the control system must include restriction on the mass position to protect the device and the ship. This restriction usually causes windup phenomenon and control performance is deteriorated seriously. Two control algorithms, anti-windup control and saturated sliding mode control, are studied in this paper. Control performance and robustness problem are checked out by numerical simulations.

Ship Flexure Error Compensation of Transfer Alignment via Robust State Estimation (강인한 상태추정에 의한 전달정렬의 선체유연성오차 보상)

  • Lim, You-Chol;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.2
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    • pp.178-184
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    • 2002
  • This paper deals with the transfer alignment problem of SDINS(StrapDown Inertial Navigation System) subjected to roll and pitch motions of the ship. In order to reduce alignment errors induced by ship body flexure, a linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonlinear measurement equation with respect to the dominant y axis component and defining the flexure state of random constant type. And then a robust state estimation scheme is introduced to account for modeling uncertainty of the flexure. By interpreting the simulation results and comparing with the velocity and DCM(Direction Cosine Matrix) partial matching method, it is shown that the proposed method is effective enough to improve the azimuth alignment performance.

Distance Measurement System using A Stereo Camera and Radial Pattern Target for Automatic Berthing Control

  • Mizuchi, Yoshiaki;Ogura, Tadashi;Hagiwara, Yoshinobu;Suzuki, Akimasa;Kim, Youngbok;Choi, Yongwoon
    • Journal of Power System Engineering
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    • v.17 no.5
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    • pp.121-127
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    • 2013
  • In this paper, we propose a distance measurement system for automatic berthing control using a stereo camera mounted on a rotation control device, and a radial pattern target. Automatically controlling the position and attitude of a ship aims to prevent maritime accidents due to human error. Our goal is to measure the relative distance between a ship and an onshore or offshore target for berthing. Therefore, the distance should be continuously measured while tracking a fixed point on a target. To this end, we developed a stereo camerabased distance measurement system that satisfied these requirements. This paper describes the structure and principle of the measurement system. We validate the distance error for target incline due to the relative position and attitude between a camera and a target in miniature scale. In addition, the findings of an experiment in an outdoor environment demonstrate that the proposed measurement system has accuracy within 1 m at a range of 20-100 m which is the acceptable accuracy for automatic berthing.

A study on the attitude affecting the preventive behavior for hearing conservation (청력보존을 위한 예방 행위에 영향을 미치는 태도 분석)

  • Rhee, Kyung-Yong;Yi, Kwan-Hyung
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.2 s.53
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    • pp.371-384
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    • 1996
  • The purpose of this study is to investigate attitude factor related to hearing conservation and to find attitude affecting the preventive behavior for hearing conservation. The research method used in this study was self-administered questionnaire. Samples of the study were composed of 353 workers exposed noise selected randomly in 10 ship-building manufacturing companies. Authors extracted following 9 factors related hearing conservation from 26 attitude propositions prepared from previous study results and health belief model; (1) general perceived susceptibility, (2) relative perceived susceptibility compared with colleagues, (3) concern to the personal protective devices, (4) perceived severity and concern to the hearing capacity, (5) concern to the hearing and noise assessment, (6) concern to the control noise and hearing conservation, (7) group pressure and reason of wearing protective devices, (8) apathy of hearing loss from noise, (9) knowledge about hearing conservation. Attitude factors affecting the preventive health behavior were general perceived susceptibility, concern to the noise control and hearing conservation, and concern to the personal protective devices in the case of wearing personal protective devices. But in the case of avoiding noise exposure as preventive health behavior, perceived severity and concern to the hearing capacity was a significant attitude factor with knowledge about hearing conservation.

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Measurement Time-Delay Error Compensation for Transfer Alignment (전달정렬의 측정치 시간지연 오차보상 기법)

  • Lim, You-Chol;Song, Gi-Won;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.11
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    • pp.953-957
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    • 2001
  • This paper is concerned with a transfer alignment method for the SDINS under ship motions. Major error sources of transfer alignment are data transfer time-delay, lever-arm velocity and ship body flexure. Specifically, to reduce alignment errors induced by measurement time-delay effects, the error compensation method through delay state augmentation is suggested. A linearized error model for the velocity and attitude matching transfer alignment system is first derived by linearizing the nonliner measurement equation with respect to its time delay and augmenting the delay state into the conventional linear state equations. And then it is shown via observability analysis and computer simulations that the delay state can be estimated and compensated during ship motions resulting in considerably less alignment errors.

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