Platedevelopment does NOT work as expected

[Johannes]

Trying DelftShip 3.2 (free version) I get a very strange behaviour at the developed plate .
The developement works correct for the bow(?) and not
for the stern.
Sometimes the plates also occur flipped by 180° ???
Inserting more points at the strait stem (or stern ?)
doesn’t help, because it produces more “knuckles” –
one for each point.
The question is – in which case can I rely on the developments ?

Best Regards
Johannes [file name=Simple_Cat_475-20100519.fbm size=30682]http://www.delftship.net/delftship/media/kunena/attachments/legacy/files/Simple_Cat_475-20100519.fbm[/file]

Attachments:

• simple_cat.JPG
• Simple_Cat_475-20100519.fbm

[Marven]

Try inserting a complete row of points from the stern to the bow.
That will fix your problem.

[Johannes]

Hi Marven,
in principle it’s getting better, but not completely !
As the attachement shows, after inserting a “row of points” (without inserting an edge) there’s still a small knuckle (stem or stern ?) at the position of
of the inserted point just on one end (red circle). After inserting the edge, the picture is the same as
at the beginning (blue circle). The other important thing is, when I insert a “row of points”, hydrostatics are changing !!
I think that special case isn’t regarded in the development function !

Best Regards
Johannes

Attachments:

• simple_cat_2.JPG

[Marven]

I noticed that you have inserted new points as suggested, but did not connect these points by inserting new edges. This way faces are introduced with more than 4 points. These generally suffer from twist which is highly undesired for develpable surfaces.

[Johannes]

Inserting the edges between the points too, generates a drastic change of the hydrostatics in the ends of the hull.
I think the procedure of developing (inside of the program) has to be fixed.

Regards
Johannes

[Author]

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