Gyroscopic Multi-Hull Design

[venomousbird]

http://www.youtube.com/watch?v=l2KbhfrcBjA
Just did a 3D design of this boat idea I had this morning.

[venomousbird]

Does the youtube embed not work on this site? I'm not having the video show up. . .

[Boat Design Net Moderator]

Originally Posted by venomousbird

Does the youtube embed not work on this site? I'm not having the video show up. . .

Only include the actual video ID within the youtube bbcode (the part after v=, for example l2KbhfrcBjA) and the youtube video will show inline.

[upchurchmr]

Perhaps you could give us a clue as to whats the point?

[venomousbird]

The idea is that the pontoons keep the part of the hull that is occupied elevated above the water, and it is suspended so that it can rotate, which cancels out the side to side rocking of the boat. Also, this way, if the exterior pontoons flip, the interior will remain upright and prevent the boat from capsizing. Basically, I wanted to eliminate the greatest weakness of a catamaran, which is, if it flips, it's done for, while retaining the advantages of low draft.

[upchurchmr]

You have so little sail area that there is no chance the boat will flip. What sail area you have will mutually intefer with the wind that it won't sail anywhere anyway. Since you will be tied to dock, you might as well just put out anchors to stabilize it. So no need for a gyroscope.

Have you ever been on even a day sailing cat? If you need to avoid side to side rocking you probably need to get a swimming pool and stay at home.

Sorry, I should never have responded at all.

[venomousbird]

Yes, I have been on cats, but I didn't do research into the sail area relative to water resistance before I made my model, I was just in a hurry to illustrate the idea. I think it's a pretty unique idea, and a workable one. Clearly the wings could be made to any size. I just read every few months about a cat capsizing and someone dying, so I thought this would be a possible solution. The advantages of low draft make cats great, but they are almost impossible to right.

[venomousbird]

I was looking for constructive criticism though, so thank you, I guess the next area I need to put research into is how exactly wing sails work.

[masalai]

Next will be stabilisers to stop a rocking horse from rocking, or grandpapa's rocking chair from rocking?

[John Perry]

Not sure there is much new here - the idea of gimballed cabins, with or without gyroscopes for stabilisation, has been around since Victorian times. There have also been numerous proposals for multihulls arranged so that they can carry on sailing after the hulls have inverted.

[venomousbird]

Seems like a great idea to me, maybe for some people getting thrown around in a moving ship is a part of the traditional sailing experience they like, but I would be more interested in safe, efficient transportation personally. I like the idea of using the pitching motion under regular conditions to produce power too. The rotation of a hull around the cabin could produce a lot of energy. These same generators could have electrical power employed to them as well to prevent pitching under worse conditions.

[CatBuilder]

Um... I think you mean "rolling" motion, not "pitching" motion.

Your design will still have plenty of unrestricted pitching. It is the rolling you have designed out of it.


Also, are the small (already mentioned) sails coupled to the main cabin/center hull area only?!? If so, how will this main cabin *not* be at a huge angle as the boat sails?

If the sails are coupled to the hulls (not pontoons), how will the boat continue on once flipped?

I don't see how this boat will work as designed - how it will continue on after a capsize while at the same time canceling out roll (not pitch).

[venomousbird]

Yes, correct, it's the rolling that is eliminated, not the pitch, stupid mistake. In further discussion I will refer to them as hulls and not pontoons. As far as correcting the rotation of the cabin against the wind I'm not exactly sure. I figured I would eventually build a model, or do some calculations to figure out exactly how much rotational pull the sails would have relative to a counterweight in the bottom of the cabin. I'm not sure how large of a counterweight would be necessary to have sufficient effect? It would cause some rotational force against the cabin, certainly, but exactly how much would depend on the conditions and surface area of the wing sails I suppose.

[CatBuilder]

Originally Posted by venomousbird

Yes, correct, it's the rolling that is eliminated, not the pitch, stupid mistake. In further discussion I will refer to them as hulls and not pontoons. As far as correcting the rotation of the cabin against the wind I'm not exactly sure. I figured I would eventually build a model, or do some calculations to figure out exactly how much rotational pull the sails would have relative to a counterweight in the bottom of the cabin. I'm not sure how large of a counterweight would be necessary to have sufficient effect? It would cause some rotational force against the cabin, certainly, but exactly how much would depend on the conditions and surface area of the wing sails I suppose.

Well, take a look at the weight of a monohull's keel for proper weight required to keep the cabin upright. Now take a look at wetted surface area, etc... required to make a catamaran of a certain length go a certain speed.

Unfortunately, I think I just found the nail in the coffin of your design.

You will need every bit as much weight as a monohull's keel to keep your center cabin area upright as the wind blows, as a monohull is just your center cabin area with a weight on the bottom.

That much weight will absolutely destroy a catamaran's performance and make it slower than a standard monohull.

Also, with the given design, you will only eliminate the rolling from the water, not the rolling from the wind gusts.

Best try again.

[venomousbird]

Good analysis, and exactly the reason I put the idea up here for critique, thank you for taking the time to explain your views. I won't give up on it just yet, but I definitely have a lot more to think about.