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Significant portions of Port Development work at the preliminary phases, can often be conducted using Kongsberg Desktop Simulation software and to the largest extent possible, using what Kongsberg refers to as Ownship Vessels which are fully interactive and their performance is completely influenced by external forces such as big ship speed, wind, and sea state.

From a pure simulation and mathematical standpoint, the desktop simulator has the same fidelity / accuracy as the full mission simulator, the primary difference being the control systems for the simulated ships, and the degree of human environmental immersion. With the desktop system, all aspects of the simulation, and ship control mechanisms are being controlled by one computer with a single user interface for the instructor, this contrasts with the fully immersive full mission ship and tug simulator where a tug captain using real control equipment drives each tug, and a real pilot with real controls and radio devices controls the big ship and co-ordinates all tug activity. Additionally, with desktop / fast-time simulation, all analysis is based on assessment of numerical outputs and data plots, in contrast, full mission simulation adds the total immersion environment which incorporates human factors, man-machine interface and the assessment (sometimes subjective) of operational feasibility and risk analysis as if the operation was being conducted in real life.

Having made this distinction, it is important then to understand that the desktop system, and to some extent fast time simulation can be used quite effectively to assess manoeuvres that are not exceedingly complex, for example emergency braking or turning manoeuvres with one or two escort tugs, the ability of two or more ship assist tugs to hold a vessel against the wind or to overcome leeway, counter the effects of current. etc. The desktop simulator can also be used to do preliminary assessments on vessel motion, adverse effects of sea state, and variations in towline load under different conditions. The limiting factor with these simulations is the simulator operator's ability to manoeuvre the tugs in a fashion and within a timeline that is consistent with real life manoeuvres (using the limited control system of a keyboard and mouse), and hence maintaining the integrity of the simulation. Also, any ship, or tug manoeuvre needs to be performed at real time speed, however manoeuvres, or portions of manoeuvres that involve no steering input or engine speed changes can be performed in fast time.

Highly detail operations and manoeuvres such as the final stages of docking, or operations requiring extensive tug re-positioning should only be performed in the integrated full mission simulator unless a certain measure of inaccuracy is deemed to be acceptable.

Examples of typical types of output from these simulations are contained in the attached sample Excel® spreadsheet:

  1. Sample Desktop Simulation Entering Basin
  2. Sample Emergency Braking Test
  3. Sample Docking at Wind Limits


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