OldSaltf

Today ships are designed on computers just like, almost, any other technical product. There are special programs for ship design but these are expensive, so I wanted to use free software for the kind of low level hobby modeling I have in mind. The lines of a ship are highly complex and again there are tools for that but for the hobbyist they are also a bit over the top, so I tried to come up with a simple way of representing ships on a computer, beginning with the frames. This is how I started to work on my Frame Analysis Tool. The goal was a program which generates, to a large part automatically, a frame representation from a sequence of x,z data points. A mathematical description of the frames of a wide variety of hull forms is challenging, because of, sometimes, not only numerous changes of radii of curvature along the frame, but reversed directions of curvature as well. Fortunately a proper method for the job has been developed quite some time ago, in the 1960ies of the last century, as far as I know. The technique is called biarc approximation which means that the frames are divided into sections which are then approximated by two arc segments. Below is an example of the kind of result you get. I wanted to use an arc sequence because it is a very simple way of getting a very good approximation to almost every type of frame plus arcs can be used to generate G code for e.g. laser cutters or CNC machines. The program is written in python because this is the script language used by the CAD program FreeCAD and because it is a simple yet very powerful programming language. You can download the program from the git hub repository below. You will find a description of biarcs and of program handling in the document included in the repository. https://github.com/juergenhumt/FrameAnalysisTool This program is published under the GNU public license, which means that you can use and modify it for any non commercial use. If you improve the program please consider uploading the new version as a branch to the git hub repository Any feedback is highly appreciated. Happy modeling, Juergen

The site gallica.bnf.fr offers various files related to ships and boats, french and other. There is e.g. a collection of etchings depicting french warships around 1800. Marine Française It takes a while to load (seems to be quite a big file). You see the first page and on the right hand side there is a small menu with a download icon (an arrow pointing downwards into a sort of file drawer). On the left hand side some more books appear, some by the famous naval historian Edmond Pâris. One of the works by Pâris is a treatise on south east Asian boats. Boats of south east asian people There is probably a lot more there. To search stuff you can use a search term with the site: qualifier (note colon behind the word site). if you enter: bateaux site:gallica.bnf.fr you get a plethora of results. If you use the site qualifier in the above manner you restrict results to just the specified site.

I modified the URL, hope it'll work now!

Dictionary offering nautical terms in: German, English, French, Spanish, Portuguese, Italian, Swedish, Danish, Dutch. Not all terms seem to be available in each language, still this might be useful to study foreign plans and sources. Happy Modeling! Nautisches_Woerterbuch

Quote: I have had the appropriate lesson now so I will try this later this evening. /Quote Perhaps you could be so kind as to post a link to the videos that have helped you? Thanks, Juergen

The capabilities of FreeCAD can be modified/enhanced by adding so called workbenches. These are basically macro packages and since I will, at some point in the future, model a frame structure (ship/boat/airplane) myself I have loaded the ship and the curved shape workbench. I wonder, Simon, whether you use any of these for your project? You also mention, that quite often you have to perform tedious, repetitive tasks. I have been using different numerical programs with a modeling capability (but not FreeCAD) and they all come with a macro (programming) language to enable you to automate such tasks. FreeCAD uses Python, one of the most powerful, elegant and easiest to learn programming languages currently available. Have you considered writing a few macros to automate part of your modeling? Cheers Juergen