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The following example consist of a single meta surface that is used to define the bow of a large varieties of ship kinds. The model permit large variations of the shape from a typical bulbous bow of large vessels to vertical bows as seen in sailing boats, for instance. First a station is defined by points as the keel, bilge, waterline and deck, plus some auxiliary points used to control the tangent of each curve, as to say to guarantee a smooth transaction between each section of the station. Then those points "runs" along the X-axis varying the coordinates, defining the station at each "X" position of the station. The points and curves of each station are the same, however transformed as defined by some "curve functions", in function of X-position. Thus, the same curve I used to define the bilge at the aft zone I also use to define the bulb at the fore end of the bow. This simple model shows the geniality, by simplicity, of a parametric model defined via meta surfaces. In this model the variables are: -Beam -Length -Depth -Draft -Entrance Angle -Stem Angle -Bilge Radius -Bulb Beam -Bulb Height Finally, TPOs is used to see the station variation along the X-axis. Regards, HB. Meta_Bow_4Forum.fdb

When working with Meta Surfaces a good way to keep things well organized is using two 3DWindows at the same time (e.g. one as a central widget, the other one as a docked widget below). Using the filter options (points, curves, surfaces and name filter at the bottom of each 3DWindow) you can display only the surface in one window and just the distributional functions in the other. This way you can alter the functions conveniently while observing the immediate effect your changes have on the Meta Surface.

Hello, here is a little example that shows a DeltaShift with one DeltaCurve for multiple root curves. This is really useful, if you have two lines created and want to apply a curvature to them without changing the definition of each line. Carsten DeltaShift.fdb

Hi folks please find attached a Feature Definition for a "Bulbous Bow Shape Analysis" and a Feature Definition which can be used in a CurveEngine for creating a MetaSurface. shapeAnalysis_Bulbous_Bow.fdf bulbous_bow_section.fdf [edited 05.10.14 - tangent analysis included] In order to replace a Bulbous-Bow-IGES-Import by a fully parametric MetaSurface you can use this Feature by execute the following steps: Create a Surface Group including all the IGES-surfacesCreate a new Feature Definition and reload the Analysis-Feature, apply and create the Feature by right click on the Feature Definition>Create FeaturePass the Surface Group to the Analysis-Feature and enter (if necessary) start- and end-position in x-direction of the bulbous bowAdditionally give a number of offsets (30-50 should be a good choice)Run the Feature This will create function curves which can be used to create a MetaSurface. The next steps should be: Re-model the function curves by e.g. FSplineCurvesCreate parameters for some values of the new curves, like start/end position, start/end tangent or area Create a CurveEngineCreate a new Feature Definition, reload the Section-Feature and applySelect the Bulbous-Bow-Section-Feature and pass the new function curves to the EngineAdditionally you can set start- end end-tangent valuesCreate a MetaSurface, select the Curve Engine and set the base positions according to the start- and end-position in x-directionNow you will have a single Metasurface, which is parametric and ready for a design study. Cheers Matthias

Hi all, Lately I've noticed that some of you, especially in automotive engineering, are interested in designing parametric intake ports, so here is one. For better comprehension I will explain the main steps I undertook. Modeling the pipe (See tutorial and/or sample "Sweep Surface") and the valve itself (simple surfaces of revolution) shouldn't pose much of a problem after completing a few basic tutorials in CAESES. The difficult part is to model the intersection area where the valve pierces the pipe geometry. Therefore I cut out an oval hole around the valve pin (see scope "02_domain_modeling"). In order to obtain a robust geometry, the remaining part of the trimmed surface has been split again into three subsurfaces (also to be found in the "02_domain_modeling" scope). The hole has then been filled with a meta surface that connects tangentially constant to the surrounding pipe and to an additional support surface perpendicular to the valve pin (01_valve|02_misc|support_surf). The meta surface has been created in circumferential direction around the (half) valve pin, see Screenshots. In the scope "03_functions" you can control the local shape of the meta surface. The blending function has influence on the connection to the support surface (1 = tangentially constant connection, 0 = perpendicular connection); speed_valve and speed_intake allow to manipulate the influence of the connecting surfaces on the meta surface. Use the mirror function in your 3D view to visualize the other half of the intake port, too. Try playing around with a few parameters that can be found in their according scopes. For more detailed insight into the meta surface creation check out the feature definition "contour_def" which holds the curve description that is used for the meta surface. the parameter "01_valve|03_motion|dz_norm" can be varied between 0 and 1 in order to close and open the valve respectively. "max_dz" in the same scope defines the maximum gap for an open valve. The .gif file should give you a few ideas how this fully parametric model can be varied, but you will probably have your own. Looking forward to questions or feedback, let me know if you think this sort of geometry could help you improve your intake port designs. Cheers, Jan 20140523_simple_intakePort.fdb