Stability script for a basic stability software

Hello everyone,

I would like to create a stability code in Excel or even better in Phyton/Matlab, I still have to decide which is the better tool to use in my case, I was wondering if you have any stability script that you can share in this forum.

I would like to be able to calculate the hydrostatics, cross curves, downflooding points, righting levers.

In particular for the larger angles, how do you get the GM and the BM angle by angle?





Thank you in advance!

 

Within Gene-Hull, the GZ can be computed for the hull with heel, by introducing an angle and by manual iteration on the elevation and the trim up to the equilibrium (displacement = weight and Xc = Xg). It is a spreadsheet application developed under open office, and is open source : you can go in the administrator space ( from line 684) and modify what you want. The application are for sailing yachts, and presently the computation with heel can be done up to the immersion of the sheer line , so about 30°-35° (future extension is in mind to deal with all angles). That can help you to develop your own spreadsheet focused on that issue specifically, keep in mind that an accurate computation need to have a connection with the hull volume definition. Here are the spreadsheet and the user guide with full details
Gene-Hull upgrade 2,3 https://www.boatdesign.net/threads/gene-hull-upgrade-2-3.60748/

 

For large angle stability there is enough of a change in the WPA and volumes that render the small angle stability assumption no longer valid. Since the values of KM etc are no longer constant. There are several ways in which to achieve your objective.
By simple cross curves of stability:


or, by constructing a curve of metacentres:


This gives you to data points you need.