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1

Consistently Trained Artificial Neural Network for Automatic Ship Berthing Control

Ahmed Y., Hasegawa K.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2015

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Vol. 9, no. 3

417--426

EN

In this paper, consistently trained Artificial Neural Network controller for automatic ship berthing is discussed. Minimum time course changing manoeuvre is utilised to ensure such consistency and a new concept named ‘virtual window’ is introduced. Such consistent teaching data are then used to train two separate multi-layered feed forward neural networks for command rudder and propeller revolution output. After proper training, several known and unknown conditions are tested to judge the effectiveness of the proposed controller using Monte Carlo simulations. After getting acceptable percentages of success, the trained networks are implemented for the free running experiment system to judge the network’s real time response for Esso Osaka 3-m model ship. The network’s behaviour during such experiments is also investigated for possible effect of initial conditions as well as wind disturbances. Moreover, since the final goal point of the proposed controller is set at some distance from the actual pier to ensure safety, therefore a study on automatic tug assistance is also discussed for the final alignment of the ship with actual pier.

2

Simulation of Load Distribution along a Quay during Unparallel Berthing Manoeuvres

Artyszuk J.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2010

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Vol. 4, no. 3

273--278

EN

The marine berths are normally secured for safety reasons with a system of fenders. Their role is to absorb and dissipate the kinetic energy of a ship coming into a contact with a berth, so the structural in-tegrity of both the berth and ship's hull is preserved. Normally the combination of a number and the single fender strength indicate the ship's maximum allowable lateral speed in parallel berthing conditions (of course, with a safety margin frequently taken into account). More or less directly and/or approximately, this is also a general selection method for fender systems. The main objective of this conference contribution, as inspired by some suggestions and needs within a domestic marine society since the author's developed and successfully implemented fender effect in ship manoeuvring simulation, is to analyse the local loads in a particular fender around the region of contact during an oblique berthing. Various conditions of ship's lateral and angu-lar velocities are tested. The results are compared with some practical shiphandling tips, as to be found in the literature, leading to a necessity of revision of the existing practice. The presented investigations are believed to be very helpful also for fender system designers.

3

Mooring the Ferry m/f “Gryf” in Extreme Hydro and Meteorological Conditions

Kowalski A.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2008

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Vol. 2, no. 4

383--386

EN

The paper introduces some possible manoeuvres of the ferry „Gryf” in difficult hydro and meteorological conditions, in which standard methods do not permit execution of mooring and unmooring. Brief characteristics of the ferry m/f „Gryf” have been presented. Typical and most often met extreme hydro and meteorological conditions have been described for ?winouj?cie and Ystad. Examplary techniques of manoeuvres have also been presented for both ports of operation.

4

An Application of ANN to Automatic Ship Berthing Using Selective Controller

Im N., Seong-Jong Lee, Hyung-Do B.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2007

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Vol. 1, no. 1

101--105

EN

This paper deals with ANN(Artificial Neural Networks) and its application to automatic ship berthing. As ship motions are expressed by a multi-term non-linear model, it is very difficult to find optimal methods for automatic ship berthing. When a ship makes its berthing operation, the ship’s inertia and slow motion make the ship approach to final berthing point with pre-determined navigation pattern. If the ship is out of the pre-determined navigation pattern, the berthing usually end in failure. It has been known that the automatic control for ship’s berthing cannot cope with various berthing situations such as various port shape and approaching directions. For these reasons, the study on automatic berthing using ANN usually have been carried out based on one port shape and predetermined approaching direction. In this paper, new algorithm with ANN controller was suggested to cope with these problems. Under newly suggested algorithm, the controller can select different weight on the link of neural networks according to various situations, so the ship can maintain stable berthing operation even in different situations. Numerical simulations are carried out with this control system to find its improvement.