The success of our port studies has resulted in an increasing demand from engineering companies for our evaluation tools, and therefore we have decided to market the actual tools towards port engineering companies. 

The port studies performed at FORCE Technology have proven their worth as the engineering companies have saved many resources by simulating the results of the constructions of new harbours or changes to existing ones before carrying them out in real life. Besides the SimFlex4 simulation software, our toolbox consists of SimFlex4 Fast-time simulation, SimFlex4 Shipyard and SimFlex4 Area Engineer which are all developed inhouse. 

SimFlex4 Area Engineer is the basis for every port engineering study and will be presented in more detail in this article. SimFlex4 Area Engineer With SimFlex4 Area Engineer, it is possible to create a new exercise area or to modify an existing one by using a number of unique features and functionalities in the process. A sea chart is shown according to the IMO S-52 display standard. The chart is highly configurable and operates in layers based on the S57 standard, each one representing a physical object type (i.e. land contours, fenders etc.). 

SimFlex4 Area Engineer provides a wide range of tools that allows each layer to be modified or extended by for instance moving, deleting, inserting and modifying objects. With SimFlex4 Area Engineer it is possible to import data from open S57 format, AutoCAD format, DTED (digital terrain elevation data format) and from different text file formats. The imported data can be used for generating detailed environment models for depth, current, wave, tide, wind, fender and banks. Furthermore, SimFlex4 Area Engineer generates information for the SimFlex4 Visual System and the SimFlex4 Radar System including detailed navigation aids and terrain. SimFlex4 Area Engineer is based on the mathematical framework used in the real-time simulators. This ensures that the responses of the ship due to impacts from depth, current, wind, waves etc. are as realistic as in our full-mission simulators. The programme is extremely user-friendly and requires limited training before use.  

Numerical navigator

Normally, the vessel is controlled by the navigator by means of standard control equipment (rudder, engine telegraph etc.) and running in realtime. However, in fast-time mode, a so-called numerical navigator controls the vessel, and the simulator is running as fast as the computer allows which enables a huge number of simulations to be completed within a short period of time. Once the fast-time simulations have been set up it is relatively easy to perform a large number of runs in various environmental conditions and various channel or harbour layouts. Hence the fast-time simulations are especially suited for relative comparisons of various harbour and navigational channel layouts, thus providing a solid basis for selection of final design. 

Realistic behaviour 

The numerical navigator controls the ship and has been developed to behave as far as possible as a mariner. It follows a pre-defined plan which might include straight legs, wheel over-line waypoints and curved tracks with a given turn rate. Furthermore, the plan includes a desired speed over ground. Human errors or misjudgements are included as a random function with a given standard deviation to obtain a number of tracks that are different and to obtain a realistic track envelope. 

Observations and corrective actions are made at discrete time intervals which are given as a mean time interval with a corresponding standard deviation. If the ship is not able to keep the planned track, and the maximum rudder angle is used, the handle setting is increased stepwise until the desired heading is reached. Then the handle setting is decreased stepwise again until the target speed is reached. The time series logged during the simulations are afterwards analyzed statistically with FORCE Technology’s own software program ‘Replay’. 

The statistical analysis provides information on e.g. controllability of the vessel, use of rudder and distances to certain structures. This is valuable for decision-making. Presently, more than 400 companies have bought licenses to the SimFlex4 engineering tools.