Overview
Reliability of the service, in terms of punctuality, operability and availability of the ships, is the attribute that most contribute to the efficiency of waterborne transport. The aim of the project is to improve ships’ performance, and thus its efficiency, by addressing those operational factors that are connected to operability and availability of the ship itself.
The effect of waves in rough weather is of the factors that mostly degrade the ship efficiency. In this way, the objective of the project will be achieved by developing an on-board decision support system for tactical decisions of ship handling in waves which enables the master to improve ship performance while minimizing the likelihood of structural damage.
Besides monitoring in real time the actual ship responses, the system will predict the near term motions and structural loads due both to weather changes and to possible changes in course and speed by the shipmaster. It is a system for tactical decisions of ship handling covering in particular situations of rough weather.
The innovation compared to existing systems lies in the prediction capability, which will be based on various computational methods. The system will be built upon existing monitoring systems from two of the partners which have been used on board of several ships. One of them monitors accelerations on board and the other monitors the cargo distribution and calculates the stability and distribution of still water loads. The decision support system will be conceived for installation on both new constructions and existing ships thus addressing the competitiveness of both the EU ship manufacturing sector (new ships) and the EU maritime transport operators (existing ships).
Objectives
The objective of this project is to develop an on-board decision support system for tactical decisions of ship handling in waves which enables the master to improve ship performance and to minimize the likelihood of structural damage. The system that is being proposed aims at predicting the near term changes in motions and loads that would arise from any change in course and speed by the shipmaster. It is a system for tactical decisions of ship handling, covering in particular situations of rough weather. It is not aimed at being a system for long range planning such as the weather route planning systems that use information on weather forecasts and plan the route of the ship during the future days along her voyage.
The main obstacles to the development of such a system are, from a scientific viewpoint, the complexity of the requested analyses as well as of its representation and, as far as technologies are concerned, the lack of monitoring devices suitable for installation and use on-board which are low cost, low maintenance, and not requiring the involvement of the operator.
These obstacles will be overcome in the present project by reaching the following objectives:
- Scientific Objectives:
- OB1: development of the theoretical background necessary to properly
forecast the occurrence and the effects on ship structures of abnormally
severe waves;
- OB2: development of a methodology allowing the assessment of the
severity of the sea state from the measured ship motions, thus avoiding
the use of radar based monitoring systems, which are costly and
operationally demanding to use;
- OB3: development of a “ship response model”, which automatically
carries out all the required analyses and provides, in real time, the
information necessary for optimal ship handling in heavy weather;
- OB4: development of a representation of the current ship structural
conditions simple and synthetic enough to be of real and concrete
support to the ship master decisions.
- Technical Objectives:
- OB5: development of monitoring devices able to accurately measure
the motions of the ship;
- OB6: development of a decision support system integrating the
various elements required for optimal ship handling in heavy weather.
The achievement of the above objectives will be verified according to the criteria provided in the following table:
| |
Criteria |
Notes |
| OB1 |
Accuracy of the effects of abnormal waves in ship motions and loads:
numerical vs. experimental data |
Experimental data provided by model tests. |
|
OB2
|
Accuracy of the assessed sea state severity similar to that achieved by
typical radar based on board systems. |
Based on numerical simulations and comparisons with model and full scale
tests |
|
OB3 |
Ability of the ship response model to deal with the effects of all the
wave loads relevant for structural assessment: hull girder loads,
slamming, acceleration and related dynamic loads, loads induced by
abnormal waves |
According to classification societies design rules and comparing with
numerical simulations |
|
OB4 |
Graphical user interface with information easy to understand
|
Assessed by pilot application on board and on a simulator. |
|
OB5 |
Ability of the sensors to correctly measure the motions |
Assessed by onboard trials |
|
OB6 |
Ability to develop pilot applications for different ship types.
|
Three pilot applications used on-board for at least 3 months. |
|