Ship Course Research Articles

Adaptive Zeroing-Gradient Controller for Ship Course Tracking With Near Singularity Considered and Zero Theoretical Tracking Error

The zeroing-gradient (ZG) method, a combination of two neural dynamics methods, has been leveraged to construct controller for solving ship course tracking problem with near singularity considered. In this paper, the existing ZG controller is presented and revisited with its limitation identified. Specifically, this paper points out that there exist lagging errors for the ZG controller with the theoretical analyses provided. Then, to remedy the weakness, a new controller is proposed with an adaptive coefficient with zero theoretical tracking errors. Moreover, different activation functions are exploited to accelerate the convergence of the proposed controller. Finally, simulations are conducted to verify the superiority of the proposed controller.

Optimized Backstepping Design for Ship Course Following Control Based on Actor-Critic Architecture With Input Saturation

This paper presents a course following control method for ships based on optimized backstepping (OB) technology. The backstepping technology is employed as the main control framework since the ship course can be modeled in the strict feedback form. Based on the actor-critic architecture and radial basis function (RBF) neural network (NN), the reinforcement learning (RL) strategy is introduced to avoid the difficulty in solving the traditional Hamilton-Jacobi-Bellman (HJB) equation directly. The actor NNs are used for carrying out the control law, while the critic NNs aim at evaluating the tracking performance. An auxiliary design system and Gaussian error function are employed to handle the practical problem of input saturation. The stability of the closed-loop system can be guaranteed via Lyapunov theory. Finally, simulation examples and comparison are provided to demonstrate and verify the superior performance and advantages on course following and energy saving of the control scheme proposed in this paper.

Управление движением судна по программной траектории при параметрической неопределенности с использованием ПИД-регулятора

Управление движением судна по программной траектории при параметрической неопределенности с использованием ПИД-регулятора

Bifurcation Controller Designs for the Generalized Cusp Plants of Bogdanov--Takens Singularity with an Application to Ship Control

Nonlinear controlled plants with Bogdanov--Takens singularity may experience surprising changes in their number of equilibria, their limit cycles, and/or their stability types when the controllers slightly vary in the vicinity of critical parameter varieties. Each such change is called a local bifurcation. We derive novel results with regards to truncated parametric normal form classification of the generalized cusp plants. Then, we suggest effective nonlinear bifurcation control law designs for precisely locating and accurately controlling many different types of bifurcations for two measurable generalized cusp plants. The first is a general quadratic plant with a possible multi-input linear controller, while the second is a \(\BbbZ_2\)-equivariant general plant with a possible multi-input linear \(\BbbZ_2\)-symmetry preserving controller. The bifurcations include from primary to quinary bifurcations of either of the following types: saddle-node, transcritical, and pitchfork of equilibria, or \(\BbbZ_2\)-equivariant bifurcations of multiple limit cycles through Hopf, homoclinic, heteroclinic, saddle-node, and saddle-connection. Criteria along with an example are proposed for frequency and amplitude-size control of the corresponding oscillating dynamics. Due to the nonlinearity of a ship maneuvering characteristic, there is a need for a controller design in a ship steering system so that the ship follows a desired sea route. The results in bifurcation control analysis are applied to two nonlinear ship course models for such controller designs. Symbolic implementations in Maple and numerical simulations in MATLAB confirm our theoretical results and accurate predictions.

Assessing a maritime service website prototype in a ship bridge simulator: navigators\u2019 experiences and perceptions of novel e-Navigation solutions

The aim of this study was to assess proof of concept and usability of a maritime service website prototype in a full-mission ship bridge simulator through Swedish mariners’ experiences and perceptions. This test was part of the European Commission’s EfficienSea2 project for e-navigation. The prototype was intended as an aid to existing standard systems and methodologies for planning, executing and monitoring voyages. The study began with 5 days of simulator trials focused on today’s standard practices. This served as a baseline to compare to subsequent 4 days of simulator trials testing the prototype. For data collection, observations, video footage, interviews, and eye tracking were used. Data analysis included breaking apart the qualitative data to capture the perceptions of the participants, and a preliminary analysis of eye-tracking data as a complement. The results suggested that the prototype could be more suitable for a route planning stage, that the participants were familiar with similar existing solutions from other manufacturers, and that the contents of the tool would be most beneficial if integrated within the Electronic Chart Display and Information Systems (ECDIS). There is a pressing need for the novel solutions to be user needs-driven, integrated with the existing technologies, and standardized across the domain, and these processes must go hand-in-hand with accounting for all involved stakeholders, procedures, regulations, and training, as this will alter the course of shipping.

Building artificial neural networks to predict direction and magnitude of wind, current and wave for sailing vessels

Current, wind, wave direction and magnitude are important factors affecting the course of ships. These factors may act positively or negatively depending on the course of a vessel. In both cases, optimisation of the route according to these conditions will improve the factors such as labour, fuel and time. In order to estimate the wind, wave, current direction and magnitude for the region to be navigated, it is necessary to develop a system that can make predictions by using historical information. Our study uses historical information from the E1M3A float—a part of the POSEIDON system. With this information being used, artificial neural networks were trained and three separate artificial neural networks were created, which can predict wind direction and speed, direction and speed of sea current, wave direction and height. For different regions, it is necessary to use artificial neural networks trained using the historical information of those regions. This study is an example of prospective studies. Keywords: Current, neural network, prediction, sailing vessels, sea, wave, wind

ВНЕДРЕНИЕ МЕТОДОВ ВЫСОКОТОЧНОГО МЕСТООПРЕДЕЛЕНИЯ НА ВНУТРЕННИХ ВОДНЫХ ПУТЯХ РОССИЙСКОЙ ФЕДЕРАЦИИ

The article discusses communication facilities for transmitting corrections and ephemeris data, analyzes methods of calculating errors of satellite position finding, and gives results of field tests for determining accuracy of the location for Real Time Kinematic and Precise Point Positioning modes. There has been carried out a survey of the existing functioning differential satellite subsystems, satellite differential correction and monitoring systems. The methods of differential coordinate correction currently used on the inland water transport provide accuracy within 1-5 meters. As in the unmanned mode the given accuracy is not sufficient, there appears the need to develop methods for calculating location finding with centimeter precision. Precise positioning relative to the axis of the ship's course will make it possible to control the vessel in the unmanned mode, as well as to use robotic facilities on water transport capable of making safe voyages on a set of waypoints tied to geographical coordinates.

The Design of Ship Formation Based on a Novel Disturbance Rejection Control

Ship formation is the common form of maritime transport, reconnaissance, and rescue, which composes the uniform formation through the coordination of individual ship motion, but it is vulnerable to external disturbances in the regulation, causing the floating of position. In view of the interference of ship adjustment, and considering the principles of active disturbance rejection, a novel disturbance rejection control was designed, combining with the artificial potential field algorithm, which applying the feedback of spacing error, to improve the impact of spacing disturbance. And then adjust the speed and course of the individual ship by sliding mode control with disturbance observer, resisting the interference of ship formation and guaranteeing the performance of ship formation. Finally analyzing and comparing the state diachronic trend of ship formation by the simulation verification, the ship state achieves consistency, reaching the goal of ship spacing and maintaining the stability of formation, which obtain good results and verify the effectiveness of algorithm.

THE OPTIMUM REGULATOR FOR THE NONLINEAR STABILIZATION SYSTEM OF THE INERTIAL CONTROL OBJECT

Designed the model of the nonlinear stabilization system of the ship course and showed experimental and theoretical research results of the selection an optimal regulator for the system, which excludes, at the same time, appearance of limit cycles in it. As research method, the method of describing function was used. Simulation of the nonlinear stabilization system of the ship course with different types of regulators allowed to perform a comparative assessment of industrial regulators. To improve the properties of the PID-regulator, it is proposed to a nonlinear correction system.

Ship Course Following and Course Keeping in Restricted Waters Based on Model Predictive Control

Ship Course Following and Course Keeping in Restricted Waters Based on Model Predictive Control

Design a Ship Autopilot using Neural Network

Ship autopilots play an important role in insurance of safe navigation and efficient transportation as else. For their successful design and development, many control techniques were and are being developed. In this paper, the application of artificial neural network (ANN) is investigated to design an autopilot for a surface ship. Feed forward multilayered architecture of ANN is used for approximation of the inverse model of the ship. The designed autopilot acts like an optimal one because of using a cost function for generation of ANN training data. The performance of designed autopilot is evaluated in still water and different wave frequencies. The stability and robustness of the designed system is proved through simulation, carried out in Matlab. The results show that the proposed autopilot can efficiently be used to control the course of a ship in a range of parameter variation. 1. Introduction The main duty of an autopilot is to keep the course of ship in a predefined direction using mostly the rudder. The safety and efficiency of transportation are directly dependent on the performance of ship autopilots. For this, a lot of techniques like proportional-integral-derivative controller, optimal control theory, adaptive control, and nonlinear control are used to improve the autopilot performance. The major feature of these approaches is that they require the exact knowledge of dynamics of controlled objects, which is difficult to obtain in practice due to complexity of ship hydrodynamics. For adaptive and nonlinear control there are some demerits like difficult design and stability analysis. The mentioned above disadvantages can be overcome by using artificial neural network (ANN) because of ANN approximation ability of arbitrary smooth function with required accuracy (Haykin 1999; Terekhov 2002). The first way of application of ANN to ship steering is to use a conventional controller for training the neural network (NN) controller (Endo et al. 1989; Burns & Richter 1996; Unar 1999; Khizer et al. 2013; Pathan et al. 2012a, 2012b; Velagic 2006; Zirilli et al. 2000; Alarcin 2007; Alarcin et al. 2010). Another way to develop NN controller is to integrate NN with other control techniques in sense of adaptive control (Cao et al. 2000; Tzung-hang et al. 2001; Ming-chung & Zi-yi 2013; Li et al. 2004; Jun & Liu 2013; Xu et al. 2014; Xiao et al. 2011; Wang et al. 2013; Yang & Zhao 2006; Leonessa & VanZwieten 2004; Hu & Pan 2012).

Design of Course-Keeping Controller for a Ship Based on Backstepping and Neural Networks

Due to the existence of uncertainties and the unknown time variant environmental disturbances for ship course nonlinear control system, the ship course adaptive neural network robust course-keeping controller is designed by combining the backstepping technique. The neural networks (NNs) are employed for the compensating of the nonlinear term of the nonlinear ship course-keeping control system. The designed adaptive laws are designed to estimate the weights of NNs and the bounds of unknown environmental disturbances. The first order commander are introduced to solve the problem of repeating differential operations in the traditional backstepping design method, which let the designed controller easier to implement in navigation practice and structure simplicity. Theoretically, it indicates that the proposed controller can track the setting course in arbitrary expected accuracy, while keeping all control signals in the ship course control closed-loop system are uniformly ultimately bounded. Finally, the training ship of Dalian Maritime University is taken for example; simulation results illustrated the effectiveness and the robustness of the proposed controller.

Economic Analysis of Hybrid Wind/PV/Diesel/ESS System on a Large Oil Tanker

Due to the global concern on the increasing amount of fossil energy consumed by traditional ships, the application of renewable energy into a ship power system provides a new solution to improve the energy efficiency and to reduce the greenhouse gas emissions. This study proposes a stand-alone power system on a large oil tanker including wind generation system, photovoltaic generation system, the diesel generator, and the energy storage system (ESS). Unlike on land, the wind generation on the shipboard not only relies on the natural wind speed but also the ship's course and speed. The installation of the wind turbines on the board is optimally designed, which takes the relative speed into account. In order to mitigate the intermittence of the renewable energy generation, a lead–acid battery serves as the ESS to enhance the stability of the ship power system, and the size is optimized by the multi-objective particle swarm optimization to minimize the whole system cost and CO2 emissions. Additionally, variations of the ship loads are considered with respect to the different operational conditions. Various cases are compared in detail to demonstrate the applicability of the proposed algorithm.

Ship Adaptive Course Keeping Control With Nonlinear Disturbance Observer

This paper investigates a scheme to reject the unknown bounded time varying external disturbance for a ship course keeping control system. A mathematical model of a steering system is derived considering nonlinear features that could affect the control design process. The feedback linearization approach is adopted to simplify the nonlinear system. The adaptive sliding mode control algorithm and nonlinear disturbance observer method are developed for course keeping maneuvers in vessel steering and for providing robust performance for the environment disturbance and rudder dynamics. Furthermore, the overall stability conditions of the presented controllers are analyzed by Lyapunov’s direct method. Finally, the effectiveness of the controllers is illustrated by the simulation results on a navy vessel with twin rudders.

Inference Engine in an Intelligent Ship Course-Keeping System.

The article presents an original design of an expert system, whose function is to automatically stabilize ship's course. The focus is put on the inference engine, a mechanism that consists of two functional components. One is responsible for the construction of state space regions, implemented on the basis of properly processed signals recorded by sensors from the input and output of an object. The other component is responsible for generating a control decision based on the knowledge obtained in the first module. The computing experiments described herein prove the effective and correct operation of the proposed system.

Measurement and Analysis of Mental Workload of Marine Team in Observing Hospital Management System

Marine Team workload is increasingly thought to affect person quality of work life and patient safety. Workflow interruptions are a frequent stressor in clinical work, impeding clinicians’ attention and contributing to clinical malpractice. We aimed to investigate prospective associations of workflow interruptions with multiple dimensions of mental workload in person during marine shifts. On entering and leaving porn a commander IIE and such a large number of operations of a rudder and motor control, that he gives orders for extension colleagues. Additionally, a ship's course control is troublesome at a low speed as it is effortlessly influenced by wind and current. On entering/leaving Port, the participation among extension partners is most essential for safe route and its significance is regular information on the planet. In any case, its assessment relies on upon a seafarer's understanding, not a quantitative record. We require an assessment technique for collaboration and relations among colleagues with the quantitative file to assess Bridge Team Management. The motivation behind this paper is to assess the mental workload of extension group on entering and leaving ports with heart rate changeability.

A Study on the Development of an Early Detection System for Altering Course of a Target Ship

This paper contributes to the development of an early detection system to detect the alteration of a target ship during early stages using the steering wheel signal via AIS communication. The feasibility of this system is also verified with a real ship trial. It was confirmed that the rudder angle on ECDIS was ordinarily marked green or red by the used rudder angle after the steering wheel operation. We were able to detect intentions for a change in course by a target ship quickly and efficiently avoid collisions. This system will contribute to more active VTS services and the analysis of marine accidents using the General Information Center On Maritime Safety & Security (GICOMS).

Time-delay wavelet network predictor based on sensitivity analysis with application to predictive ship course control

An improved time-delay wavelet neural network (WNN) is proposed to represent the complex nonlinear and time-varying dynamics of ship motion based on sensitivity analysis approach. To improve the generalization performance of WNN, inputs of the wavelet network are selected based on their relative co ntribution to the overall output. To evaluate the contribution of inputs in the WNN, an index is proposed referred to as relative contribution rate (RCR). The resulted network is utilized as an online ship motion predictor. Based on the predictor, a predictive PID controller is presented and implemented in a ship course-following control. Simulation of online predictive ship course-following control was conducted and results demonstrate the feasibility and efficiency of the WNN predictor and the WNN-based predictive control strategy.

개항의 항계 안에서의 선박충돌에 따른 법률상의 쟁점 -해양안전심판원의 재결사례에 대한 분석을 중심으로-

Abstract Open port has the designated course and traffic jam of ships happens often. This fact may connect to ship crash easily. And the accident happens due to violation of navigation mainly. In ship crash between Neoblue and Shinkwang 7 at incheon open port, the Korean incheon maritime safety tribunal shows that the violation of navigation and duty of attention at the open port would produce ship crash directly. Wherefore, the interpretation and application of navigation are important to protect future ship crash accident. The points of navigation as objects of study are divided into two categories, interpretation and application of navigation on crashing between the ship which navigate the designated course and the ship which enter into the designated course from the another course or outside the course, interpretation and application of navigation on crashing between two or more ships, which navigate violating the navigation every ships and violating agreement rule each other. And as conclusion, I refer the legal responsibility both Neoblue and Shinkwang 7 in detail. The results of this study as follows : First, in case of crashing between the ship which navigate the designated course and the ship which enter into the designated course from the another course or outside the course, public order in open port act can be applied by priority. However, in applying the public order the principle of trust and reasons of crew, cause and effect, the time of navigation application are mandatory considerations. Second, in case of crashing between two or more ships, which navigate violating the navigation every ships and violating agreement rule each other, we should focus on the reasons of crew. Also, the reasons of crew need strict conditions. These means that the awareness of crash danger and recognition of special circumstance including limit state of ships, existence of emergency danger, non escaping crash danger by only observance of navigation. And in case of this state the public order the principle of trust and reasons of crew, cause and effect, the time of navigation application should be considered by priority, too. Key words : The Korean maritime safety tribunal, Open Port, Ship Crash, Navigation, Principle of Trust, Reasons of Crew, Public Order in Open Ports Act, Cause and EffectCorresponding Author : 051-629-5896, winterprey@pknu.ac.kr (2015 ) .

Global generalised exponential/finite-time control for course-keeping of ships

ABSTRACTThis paper addresses the global generalised exponential/finite-time control of the nonlinear ship course system with an unknown control coefficient. Different from the well-known Nussbaum-gain adaptive rule, a new Lyapunov-based adaptive logic switching rule is proposed to seek the correct control direction of the ship course system. The main advantage of the proposed controller is that it guarantees the global generalised exponential/finite-time control of closed-loop systems. Theoretical analysis and simulation results show the effectiveness of the developed control method.