Best Marine Design Software for Hull Modeling? (2008-09)

[JosephT]

Originally Posted by rocknrule

There are 3 not even listed that are way, way ahead of the rest.
PTC CADDS 5
UGS NX
Catia

I concur, some of the best modeling tools are not listed. I use Freeship to generate basic hull lines, then import them into NX and do all the detailed design there. NX has a shipbuilding module, but it's overkill for most smaller boat design applications.

[dreamer]

Originally Posted by JosephT

I concur, some of the best modeling tools are not listed. I use Freeship to generate basic hull lines, then import them into NX and do all the detailed design there. NX has a shipbuilding module, but it's overkill for most smaller boat design applications.

Similar process here using Rhinomarine for hull design then SolidWorks to finish. It is possible to creat a hull in SolidWorks, but after dozens and dozens of attempts, it's apparent that they still are not quite there. The nice thing now, however, is that SolidWorks is semi-parametric now with Rhino. I can make a change in the Rhino model and propogate that through SolidWorks. Very handy.

Problem with CADDS5 (besides being ancient) and Catia are the hugemongous expense in the purchase of the software and the very steep learning curve. Both of which are totally unneccessary for pleasure craft but are probably worth the investment for large-scale ship design.

[MikeJohns]

When you design a hull you wrap a surface around the target measurements and coefficients. Then it is more useful to look at packages that can do this automatically and actually compare them.

Shipbuilding is quite different to hull modelling. Shipbuilding packages and addons all work similarly. Ship design is of course a collaborative team effort and shipbuilding modules facilitate that and add some special modules for piping cabling etc. Sure that makes them more capable. However for 'boat' design it would be excessive to buy and use this type of package.

The simpler the cheaper and the lower the learning curve the better it is.
I put a budding engineer with no more than Autocad experience on Rhino, by the end of the day he was working with it producing complex solid models for analysis.

In a small design office designing boats not ships I think you would be hard pressed to beat Rhino with the Rhino-marine or the Orcad addin if you use it to its full extent it's surprisingly capable for it's cost.

[Andrew Mason]

Originally Posted by Ad Hoc

"...You then have to adjust the trim and draft iteratively until the buoyancy ballances the weight and the longitudinal CoB is the same as the LCG.."

If you understand the basic principals, there is no iteration.
It is a simple couple and hence a moment calculation in terms of what mass over what distance to balance. From your MCT you can also see, before hand, how much trim is expected.

The design process is iterative, the calculations are simple 'one liners'.

If LCB didn't move as draft changed, and displacement didn't change as trim changed, and MCT didn't change as draft and trim changed, what you have written might be true.

Unfortunately, its not that simple.

[Ad Hoc]

Andrew

With a print out of hydrostatics, it is that simple. Since it is just a moment change owing to the distance between the CoG and CoB horizontally.

[Andrew Mason]

Originally Posted by Ad Hoc

Andrew

With a print out of hydrostatics, it is that simple. Since it is just a moment change owing to the distance between the CoG and CoB horizontally.

Unfortunately, its not that simple. For small changes of trim with relatively constant hull shapes the approximation is reasonable. Larger differences between LCB and LCG, or hulls with bulb bows or overhangs will require iteration

[Ad Hoc]

Andrew

Within a computer environment this may well be the case.

But from a naval architecture, looking at the design spiral, it isn't. It is very simple. Since minor errors or differences are ignored in the first few stages of the design. The hydrostatics will tell me if i have a 30 or 40tm moment to overcome, for example. If it indicates a 0.3 or 0.4tm moment, in the early stages of design, not worth considering, since other factors will come into play which will affect this value later anyway. But a 30 or 40tm moment is not so easy to overcome once the design has been "set".

[Andrew Mason]

Originally Posted by Ad Hoc

Andrew

Within a computer environment this may well be the case.

But from a naval architecture, looking at the design spiral, it isn't. It is very simple. Since minor errors or differences are ignored in the first few stages of the design. The hydrostatics will tell me if i have a 30 or 40tm moment to overcome, for example. If it indicates a 0.3 or 0.4tm moment, in the early stages of design, not worth considering, since other factors will come into play which will affect this value later anyway. But a 30 or 40tm moment is not so easy to overcome once the design has been "set".

Sorry, I was talking about getting accurate hydrostatics.

[Ad Hoc]

Andrew

yes, i suspected as such, hence my qualifier re: with a print out of hydrostatics and in a computer environment.

[shellexpansion]

There is one software that should be listed here. orca 3d. It is rhino based tool, and not that expensive. The key players for "orca 3d" are the guys who has created fastship, now fastship belongs to aveva. Fastship should be also in the list.

[yipster]

not really a pro i agree on that, at leisure still trying maxsurf whitch is an excelent program!
heard of orca before, fastship i had my hands on once for hours at a show and not in the list?

[pamarine]

Using SW2008 at the moment. It works fine for the simple hulls we are doing. But I tried exactly 1 realitively complex shape and realise this ain't the program to really be using for Hull Design.

I also have Rhino and RhinoMarine, but aside from importing files from SW to run Hydrostatics i haven't really used them.

[dreamer]

It's a shame really, because SWorks has terrific surfacing tools except for hulls! The converging profiles at the bow are the biggest problem. It's actually due to the surfaces being too accurate. The surface manipulation tools are too localized for the surface. Rhino's (and others, I presume) abilty to edit surfaces using a controling net overall allows for more general hull fairing. I keep hoping SWorks will do something about this. There is a tool that allows freeform editing of the surface by directly edting isoline, but that is not general enough and stops short of the net-editing ability in Rhino.

OTOH, SWorks is great for developable surfaces. The sheet metal functionality built in to SolidWorks is pretty incredible.

Also too, I feel SolidWorks is one of the best for modeling everything else. In terms of hulls, I go back and forth between SWorks and Rhino. In SolidWorks, it's very easy to 'expand' a 2D lines plan. You can then import the 3D lines into Rhino and use network of curves to map the surface. Then import the surface into SolidWorks. SolidWorks keeps one-way associativity to the Rhino model, so if you make a change in Rhino, it will update in SolidWorks. Very handy.

[valber]

I like SolidWorks with MultiSurf... But NX works - > It was made for 20 min
And another example ->Inland foreship NX works...

[Felix Muehlhoff]

The great advantage of NX is doing everthing in one software packet. So hull design, fairing, basic hydrostatics, GA, basic design, detailed design, workshop drawings, expansions, cutparts, FEM calculations, simulation etc.. NX's kernel is the Siemens Parasolid Kernel so for advanced stability calculations GRC's Paramarine is perfect. It is also working on Siemens Parasolid Kernel so you can directly import solid data from NX and calculate.