sci-fi catamaran design help

[arkanoid]

Hi everybody. I'm a 3d visualizer and I'm working on this concept catamaran. I'm not too concerned about perfect believability; rather I'm looking for major design error in the shape (of course I think there are).
The model is still on sketch stage, but since I like the pure design as it's coming out I decided to do it just a bit more realistic then my free hand can do for what is concerned with general hydrodinamics, slopes and weight balance.
Then I will do a proper still render with it in a nice environment. You can see it's a sort of sci-fi armored military boat. Don't know if I'm going to put some sort of device to let that monster do some slow terrain movement too. In fact the original idea was to make an amphibious boat-tank.
Dimensions are 8 m. lenght, 4 m. width, 3 m. height. The height of the empty space between the hulls is 1 m. The sides are open to let the soldiers shoot from. The hole in the center is for the pilot and another shooter on top.
I'd really appreciate to hear comments from some of you. Certainly I don't need to go technical, but only some generic advices.
Don't hesitate criticizing!
Thanks,

Lorenzo

the "top" view of the first image is the bottom view

[TeddyDiver]

Is it supposed to be planning or displacement?? Now it's a bit like smth btw but not actually neither, nor semi...
Some resemblance to StarWars Gunship.. Nice..
BR Teddy

[Alik]

Sorry to say this: looks like piece of used tissue...

[Lurvio]

Looks like something for a videogame. If it aint going to be build real life, I think it looks cool. Might even float right side up.

[arkanoid]

Thanks for your comments guys.

@ TeddyDiver - Not sure what's your asking, but if you mean if it has to be built in reality the answer is no. But anyway I want it to look much more realistic. People looking at it shape have to think it could be built and it can move swifty in water.

@ Alik - Haha you're probably right. But as I said it's only a sketch now, I'm blocking shapes out.

@ Lurvio - Yes the idea is to build something that you could find in a sci fi film or videogame. But I'm going to give it a realistic setting. It has to be very "techy" but not too fancy; definitely not an alien 40.000 a.D. setting. Something like you can find in near future or hided in present..

The comments I'd like to have are like "the submerged part of the hulls is far too small. You have to do it like...", or "those side apertures are going to slow it 50% during fast turns". Or "Proportions are completerly wrong! You shoud halfen the height and...". Something like that.
At this point, I still can radically modify the model with your advices. If I was on a more advanced design stage it would be harder to do it.
I'll try to do a previz with a smoother model to show you better the current shape.

[Alik]

Originally Posted by arkanoid

The comments I'd like to have are like "the submerged part of the hulls is far too small.

Yes, we can comment this way! Just please show us where the hulls are, and where the submersed part of those.

[magwas]

Have you seen these yet?
http://www.gizmag.com/go/7217/
http://newwars.wordpress.com/2009/01...in-soft-power/

[arkanoid]

Originally Posted by Alik

Yes, we can comment this way! Just please show us where the hulls are, and where the submersed part of those.

You're completely right, I'll do some sketches with basic indications of supposed water level, engine and weapons position, wheel etc.
Stay tuned!

Thanks magwas. I saw the war vessel before. It's very cool but not so useful for my project because the size is completely different. Didn't see the first one. That's a very interesting solution; there's too much empty deck space, but I could use it as a reference. It's very minimalist though, contrary to mine. From the same blog I also like this concept for the amphibious side (not too good looking though); but it is more a tank then a boat (very slow in water).
http://www.gizmag.com/go/6906/picture/31734/
I like aslo this trimaran solution but I think it's very far from my needs.
http://www.gizmag.com/adi-gil-stealt...icture/107952/

[dskira]

What is that?

[Joe Petrich]

The models as shown look slow. The hulls as shown in Magwas' first link (Gizmag) look right for a futuristic fast design, Assuming that we will have very light, strong materials in the future you could pile your superstructure on top of hulls similar to those.

[rambat]

More like this hull
http://www.gizmag.com/go/3768/

[arkanoid]

Hi I've done an animated turntable with a temporarily smoothed version of my model. Here it is

This is a little scheme of some of the ideas:


@ Joe Petrich - can you explain why is it looking slow? Is it for proportions or shapes or other?
Consider my boat have to be fast, but not the fastest on earth, because have to grant an armour protection against enemy fire, and I suspect that armour just have to be heavy. You know, policemen have often fast cars but don't go to work with a F1.
I like the AO project showed in Magwas first link, but it's much bigger then mine, so I don't know if I can grab proportions from that.
I want my boat to be as compact as possible (and consequentely swifter); so I'll take adventage from that to make a question: why all those hulls are so long? What's the advantage in having longer hulls? Is it for stability? speed?
Well it's late now, tomorrow I'll post some bigger render with the smoothed version too. And then I'm going back to apply some of your advices.

@ Rambat - That's an interesting base for my boats... hehe. But I'm not sure I want a standing-thing like that to actually become my boat. I want a sneaky-silent-little-assault-sea-tank!

[magwas]

It seems vulnerable to shots from abeam. I know, making it more closed there would be visually uninteresting.

[Alik]

Police boats are designed to enable police personell board other boats. Thus they need clear foredeck with handholds, fendering system, gun mounts, etc.

[arkanoid]

I hope with these images you can understand better what I'm doing. Since I'm working with polygons and not NURBS curves, this fase of "smoothing" the angles is not necessary to me now that I still have to modify the main shapes. Off course this still is only a sketchy preview.
Now I want to check your ideas about main proportions and shapes! Also feel free to ask and express whatever you think about.

Originally Posted by magwas

It seems vulnerable to shots from abeam. I know, making it more closed there would be visually uninteresting.

No you're right. The side openings are there to let the soldiers shoot. But then I'm going to add a float backing. These panels have to supply also aerodynamical support to the "cabin" shape, as I suspect all those angles and the two side holes are going to heavily bound the boat. So the coverage will be on during fast rides and shooting, and off in all other cases.
I was not satisfied with the frontal view so I further opened the side (on the top), to form a semicircle around the center and let 3-4 soldiers stand on a side and have a good perspective all around.

Originally Posted by Alik

Police boats are designed to enable police personell board other boats. Thus they need clear foredeck with handholds, fendering system, gun mounts, etc.

Ok, my boat was intended to be military, not police's. But I guess it should be very similar in functions. I will consider adding space with handholds for boarding. That could be the excuse to convert to a more AO-similar boat. Thanks for this.