Explaining Ships Dynamic and Handling Using MATLAB & SIMULINK as Simulation Tool in Teaching Maritime Students
The understanding of basic mechanical problems is vital to form a sound basis for maritime students to be prepared for the specific parts of the syllabus in later semesters in order to explain Ships Dynamic and Handling. Normally simulators are used for familiarisation with the practical aspect of ship manoeuvrability. However, for providing knowledge on university level it is necessary to explain the dynamics of ship motion characteristic in more detail and based on the mathematical equation of ships motion. In the paper and presentation some examples will be given on how to use the software package MATLAB & SIMULINK as simulation Tool in teaching maritime students and even to build up more sophisticated programs for use in teaching, simulation and on board ships. The introduction starts with a simplified approach of the Equations of ships motion and samples for manoeuvres on straight track like coasting from full ahead to stop. Extending the equation for steering forces gives access to discuss steering motion of ships. Simplified Modelling of ships forces acting on the vessel like thrust and steering forces complete the set of equations. The graphical representation of the dynamic system by blocks in SIMULINK allows for an overview easy to understand to students as a sort of flow diagram. Results from fast time simulation of several manoeuvres using a more enhanced program version SIMOPT allow for a discussion of yaw stability of ships and its impact on steering quality. A simplified model for rolling motion of ships is given and some examples are simulated to explain the general effects of stability and wave parameters. The relation of these results to the more practical use for decision making to avoid resonance effects of ships in waves by loading operations or speed/course changes is demonstrated by means of a sophisticated software tool ARROW interfaced to a voyage planning program.