# Stefan Harries

Moderators

13

1. ## Utilize CAESES / FRIENDSHIP-Framework to read off data from diagrams

Hi, Sometimes diagrams with important data are available only as graphics files (e.g. after scanning from a report or upon exporting from a pdf-file). CAESES / FRIENDSHIP-Framework can be quickly utilized to read off data from diagrams with high accuracy. To do so, import the graphics as an png-file within a "GL Picture Frame" (1st step). Upon setting the scales of abscissa (x-axis) and ordinate (y-axis) (2nd step) you can readily position a point in your diagram and get your x- and y-coordinates (3rd step). (You may want to use such a point to check the level of accuracy.) Furthermore, you can approximate a graph with a curve, say a B-spline curve (4th step) or interpolate it (5th step). Using the curve representation you can "inquire" the y-value for any given x-value (6th step). The attached fdb-project illustrates the work flow for an imaginary speed-power curve. In addition to using CAESES / FRIENDSHIP-Framework to extract data points from diagrams, you can follow the same approach to replicate a lines plan of a boat, yacht or ship, circumventing classic digitization. Offset data are thus produced effectively. Nice side effect is that you can adjust selected points, for instance to improve accuracy of lines remodeling and "repair" apparent outliers. Kind regards, Stefan ExampleDiagram.zip
2. ## Wigley hull

Hi, One of the famous hull forms found in literature is the so-called Wigley hull. It is mathematically defined, see attached formula, and used regularly for tests and validation work. By definition the Wigley hull is a (simple) fully parametric model with beam, draft and height as parameters to control the shape (often normalized by length). A realization of the Wigley hull via a MetaSurface that captures the mathematical formula is given in the attached CAESES project. In addition, some partially parametric modifications are shown, namely, Lackenby type swinging of sections that is realized via a DeltaShift. (Please note that a Generalized Lackenby variation would also be available but was not used here in order to keep the project light.) If you need the hull for your CFD validation work you can use the various exports for panels, offsets, STL, iges etc. More information about ship hull design can be found in the marine section of the CAESES website. Kind regards, Stefan standardWigley.fdb