COMPIT 2004 in Siguenza/ Spain - Institut für Entwerfen von ...

(small) parts of circles. The limitation of tools to describe form elements limited the potential designs.
Wooden ships of the 16 th century used already the ship definition based on cross sections erected on
the longitudinal keel. The hull planks were aligned along thin wooden splines over the cross sections,
Fig.16. These splines can be regarded as the forefathers of the splines used later on drawing tables to
create ship lines on paper, Fig.17, and the mathematical splines used in CAD (computer aided design)
programs, Fig.18. Harries (1998) is recommended for a good overview of the state of the art in ship
hull design systems.
Fig.19: Development of ship CAD systems towards three-dimensional product models, Aarnio (2000)
(a) 3-d CFD grid of SES ship
(b) Direct export to VRML
(c) Post-processed VRML model
(d) View in browser with streamlines
Fig.20: Virtual Reality models offer sometimes better visualization, but require usually some work
as direct export from CAD gives formally correct syntax, but not functionality, Lindenau and
Bertram (2003),
http://www.ifs.tu-harburg.de/IFS/AB/AB-3-13/Arbeitsschwerpunkte/VRML_HTML/vrml_main.htm
While we retained essentially the same representation of ships over centuries, the progress in CAD
systems towards three-dimensional product data models, Fig.19, allows today not only to perform a
large variety of analyses and simulations (as discussed in chapter 3), but also advanced representation
in photo-realistic displays or in Virtual Reality. While better visualization options are a bonus, but the
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