New small boat patent

[icetreader]

The USPTO published my patent #6871608 "Twin hull personal watercraft".
This invention offers improvements in stability, comfort, speed and versatility compared to canoes, kayaks, dinghies and other small boats.

Designers, builders and manufacturers are welcome to read it and email me their comments and questions.

http://www.USPTO.gov

Yoav

Yoav Rosen
WAVEWALK, INC.

[mackid068]

Bravo!!!!!

[Tim B]

hummmm, sounds to me like that's an attempt to patent a small catamaran. (obviously) but interestingly, it gives no clear limit on size. So is a fair-sized sailing cat whithin the range of this patent?

Sorry to be negative, but in this game patents really serve to slow down progress of the sailing world as a whole. By the time anyone infinges the patent you've generally moved on to better solutions, so what's the problem? Unless someone tries to commer******e the idea; in which case, why didn't you do it when it was new?

Don't want to put a damper on it,

Tim B.

[Tim B]

oh, apologies, I hadn't read the full thing. Evidently it does give a clear limit on size, so my first point is invalid. My second point stands, though.

Tim B.

[JEM]

As a novice patent reader, what I take away as the main innovation is constructing to allow having your legs inside the pontoons.

What I know about patent enforcement you could fit in a thimble.

[Robert Gainer]

Is this an idea that might be dangerous instead of an improvement? A small kayak can be rolled and righted in one move and this might be as stable upside down as it is rightside up. More then that, this looks like a catamaran. How is this different and why does it justify a patent.
Robert Gainer

[mackid068]

It's twin hulled SMALL watercraft ie TWIN HULLED Personal Watercraft.

[Robert Gainer]

mackid068,
OH, it's two hulls, like, in twin hulls, like, a catamaran. Did you read the patent and its comments about small boats? I read it to say this is a "safe or better" substitute for boats like a kayak. I question that and the originality as far as if its so new as to be patentable. I see a lot of catamarans going back at least to the mid 1800 and if you count Polynesian craft, twin hulls go back several hundred years. Can you sum up what it is that makes this craft unique and innovative?
Thanks for clearing that up for me,
Robert Gainer

[icetreader]

mackid068,
OH, it's two hulls, like, in twin hulls, like, a catamaran. Did you read the patent and its comments about small boats? I read it to say this is a "safe or better" substitute for boats like a kayak. I question that and the originality as far as if its so new as to be patentable. I see a lot of catamarans going back at least to the mid 1800 and if you count Polynesian craft, twin hulls go back several hundred years. Can you sum up what it is that makes this craft unique and innovative?
Thanks for clearing that up for me,
Robert Gainer Robert,
One can't expect to always understand a patent from first reading or without serious knowledge of patent laws as well as the details of prior inventions and products. This is why it is not a good idea to file a patent application without a patent lawyer or editor and a technical editor working as a team with you, and without doing a very serious research on "prior art":
1. The US Patent and Trademark Office examiners will reject your claims.
2. You might get a claim that has no merit allowed, which is worse for you in the long run.

The actual intellectual property is defined in the "Claims" section of the patent. This particular US patent (#6871608) mentions some 70 prior inventions and products in its introduction and discussion on "prior art"*.
Some of those inventions and products that are particulary relevant to understanding why this invention is "New, useful and can be actually applied" are discussed in detail in the patent itself, as required by the USPTO.
When applied in small paddle craft like kayaks and canoes this new technology (see "Claims" section) improves stability, comfort, versatility and speed, or shortly: hydrostatics, hydrodynamics, ergonomics and biomechanics.

This invention also allows most people to participate in a new family of paddle sports practiced in the standing position I.E. to paddle-ski in optimal conditions.

But these are just words with a limited power of explanation.
If you're really intetrested in understanding what makes small paddle crafts based on this invention better than traditional canoes and kayaks you'd better visit my website http://www.wavewalk.com where you'll be able to see many photos demonstrating those advantages, read the Q&A, and most recommended of all watch the demo movies: http://www.wavewalk.com/DEMO%20VIDEOS.html

When this boat invention is applied in other small boats (E.G. sailing boats) it offers similar advantages. You can find some photos and other information on these aspects of this invention in other parts of my website as well as in some threads on boatdesign.net (some with with drawings)

BTW-- I'm more than willing to discuss the comparative safety, ergonomics and speed of kayaks, canoes and W boats in a new thread dedicated to this subject.

Yoav

*After having gone through nearly 1,000 US and foreign patents in the field of small boats and watersports equipemnt I can't remember a patent that offers a longer list of "prior art" in this field than this US patent # 6871608.

[mackid068]

Good idea Yoav. How about a whole section of the forum devoted to boats under 20' LOA?

[icetreader]

Mackid, do you mean "MICRONAUTICS"? http://boatdesign.net/forums/images/smilies/cool.gif http://boatdesign.net/forums/images/smilies/biggrin.gif

I think a section would be great and furthermore, when it comes to really small, lightweight and low-volume boats for 1-2 persons there's a place for developing some "unified approach", "field of research" or "science".
The reason for that is that in many ways a PWC has more in common with a kayak than it has with a big motorboat for multiple passengers, and a moth has more in common with a windsurfing board than it has with a big sailing yacht.
It's not jsut size but the whole set of interactions between the passenger's weight, skills and abilities and the tiny craft.

Another analogy that comes to my mind is the relationaship between a motorbike and a bike: These two vehicles have more in common with each other than the motorbike has with big motorized vehicles.

The definition I have in mind is "Micronautics" -The study of the mutual relationship between small, personal water crafts and their users, and the application of this knowlegde in the design and manufacturing of such water crafts.

Yoav

[JEM]

I'm finding out reading various patents can get addicting! I came back upon this one and in reading it, a question popped into my head. Now keep in mind I know zero about patent law and am not looking to become an expert nor do I expect anyone on this board to be an expert.

Anyway, my question: In reading utility patents (this one and others), I get the impression that the concept is not what is necessarily being protected, but a specific shape and size of a concept.

In other words, and I'll use this patent for example purposes, the utility patent is not trying to claim protection rights to all tunnel hull shapes, but it is claiming rights to the specific size and shape listed in the patent.

Anyone know if this sounds correct?

[cyclops]

You are asking a Cyclops, with one good eye??

[marshmat]

I do like the boat, Icetreader. Would like to try piloting one sometime!

As far as patents go.... I'd advise also getting patents in other countries or internationally if you're up to it.... While US patents generally hold up in court, the USPTO lost some respect internationally after they allowed biotech companies to patent parts of the human genome (not just analysis techniques, but actual genes). So now there's questions floating around (some valid, some not) about how honest and ethical the USPTO is with regards to other types of patents. And it's always a good idea to cover at least your main marketing territories with separate patents in each country, just in case. They're cheap compared to the cost of getting your design ripped off.

[mackid068]

Internationally sounds like a good idea. But would an int'l pat. truly hold up int'nat'ly. L'o'l.

[icetreader]

I do like the boat, Icetreader. Would like to try piloting one sometime!

As far as patents go.... I'd advise also getting patents in other countries or internationally if you're up to it.... While US patents generally hold up in court, the USPTO lost some respect internationally after they allowed biotech companies to patent parts of the human genome (not just analysis techniques, but actual genes). So now there's questions floating around (some valid, some not) about how honest and ethical the USPTO is with regards to other types of patents. And it's always a good idea to cover at least your main marketing territories with separate patents in each country, just in case. They're cheap compared to the cost of getting your design ripped off.
Thanks Matt :)

Like other things in life, it's a matter of priorities:
The biggest markets for boats using the 'W' invention are in the US, and this is why it was essential to patent it here.
Patenting in additional countries is difficult, expensive and not necessarily cost-effective in view of the relative size of those markets and the efforts required to develop them.

BTW, I uploaded a new page with a number of possible concept designs in various 'micronautical' applications: http://www.wavewalk.com/BOAT%20DESIGN%20GALLERY.html

You're also welcome to visit my gallery here on BoatDesign.

Yoav

[Deering]

Yoav,

I'm a long-time paddler and a multi-hull fan. I like what you've done! For certain applications your boat makes a lot of sense -fishing, carrying kids/pets, and as a dinghy for a big boat. A few questions:

1. Have you researched a longer boat for tandem use and greater load capacity? More suitable for longer trips? Obviously that means a large tooling expense for you, but have you done any prototypes/designs?

2. Does the Wavewalk have much rocker? Or is steering accomplished solely with lean? If no rocker, have you payed around with that variable?

3. What's the hull profile like? Looks like it has a flat bottom on the inside, similar to a dory. Did you cant the bottom(s) to facilitate turning?

Very cool.

[icetreader]

Yoav,

I'm a long-time paddler and a multi-hull fan. I like what you've done! For certain applications your boat makes a lot of sense -fishing, carrying kids/pets, and as a dinghy for a big boat. A few questions:

1. Have you researched a longer boat for tandem use and greater load capacity? More suitable for longer trips? Obviously that means a large tooling expense for you, but have you done any prototypes/designs?

2. Does the Wavewalk have much rocker? Or is steering accomplished solely with lean? If no rocker, have you payed around with that variable?

3. What's the hull profile like? Looks like it has a flat bottom on the inside, similar to a dory. Did you cant the bottom(s) to facilitate turning?

Very cool.
Thanks Deering,

1. We took 2 short plastic W kayaks, cut them and welded them together (sounds barbaric, I know :p ) to create a 15' long experimental model. The thing looked like ...well, hmmm...-like something you don't want to step on let alone sit inside and paddle it, but it performed really well: considerably faster and stabler than our small production model. There are some pictures of it on this page: http://www.wavewalk.com/BOAT%20DESIGN%20GALLERY.html
In fact, I'm looking for people interested to cooperate with me on building long W kayaks/boats for paddling and other applications. The design is easy and partly done already.

2. The W kayak (W1) has little rocker. You don't need a rudder for it to track or turn - Same thing for the 15 footer we tested.
BTW, there's a lot you can achieve with W kayaks/boats simply by changing your location along the longitudinal saddle, see details in paragraph about surf launching in this page: http://www.wavewalk.com/SURFING.html

3. You can use any profile you want. In the case of the small, narrow W kayak (W1) we used an almost square profile, see bottom of this page: http://www.wavewalk.com/PADDLING%20POSITIONS.html
It increases lateral stability by acting as an 'extremely hard' chine (see demo movies page) but even so, turning is easy because of the ability to lean into the turn and use the inner hull as an 'ad hoc rudder'.

Yoav

[DanishBagger]

Is it just me, but isn't the center of gravity rahter high in that, meaning that although it has a higher initial stability it will have tendency to toss you like you're riding a horse at a rodeo?

I'm thinking that, in waves, it will float with the surface of the water, and because of that, it will actually be easier to tip over because of that extra high cog?

[icetreader]

isn't the center of gravity rahter high in that, meaning that although it has a higher initial stability it will have tendency to toss you like you're riding a horse at a rodeo? I'm thinking that, in waves, it will float with the surface of the water, and because of that, it will actually be easier to tip over because of that extra high cog?
Hi Andre, welcome to boatdesign :)

The CG of W boats is indeed higher than that of comparable monohull kayaks, but the total stability offered is better.
This has to do with 2 things:
1. The W's buoyancy is distributed along its sides instead of being concentrated along its longitudinal axis without contributing much in terms of stability.
2. In combination with #1, the W passenger/s are offered the possibility to balance themselves effectively with their legs, and indeed your analogy with horse riding is highly appropriate.

The passengers' role is critical in micronautical design. Static stability is often not sufficient and the boat's overall stability (static + dynamic) depends on the users' successful interaction with it. This is of course different from what you find in bigger boats, where the body position and movements of a single passenger rarely have a critical effect on the boat's behavior.

You can watch some videos demonstrating the W stability in different environments and applications on this page:
http://www.wavewalk.com/DEMO%20VIDEOS.html
And you can also read about related stability, biomechanic and ergonomic issues on this page:
http://www.wavewalk.com/PADDLING%20POSITIONS.html

Yoav

[DanishBagger]

Thanks for your welcome and your explanation :)

It still seems a bit out-there, somehow, but I'm nowhere knowledgeable enough to be able to qualify that enough. Your explanation seems like, to use another stupid analogy, to be riding a bicycle, where you really move the bike in and out of the cg in order to keep it balanced, hence why it is hard to do if it's icey. Smack!! Wham!! like sitting on top of a pole with a wheel under it.. As oppose to the traditional design where your bum is below the cg, thus levelling the forces out a bit.

Andre

[icetreader]

Andre,

A kayak designer once told me that 'The W is to the [traditional] kayak what the bicycle is to the unicycle'...
By that I think he he wanted to say that the W is more stable but the unicycle is more fun (in his opinion) :).
The W passengers apply their weight through their legs and feet at the boat's lowest point, that is at the bottom of the hulls - below waterline. Each hull is buoyant enough to offer support for the user's entire weight.
This video demonstrates the reduced effect that lateral waves have on the W boat: http://www.wavewalk.com/Surf_02.WMV
And this one shows how you can jump in this 25" (63 cm) wide boat:
http://www.wavewalk.com/Stability%20-%20Jumping%20in%20the%20boat.WMV

Yoav

[DanishBagger]

Well, the problem, as I see it, is still the same. Because of the higher centre of gravity, it's like sitting on top of ball, instead of in "the middle". I don't doubt your numbers or anything, I simply don't believe that it is any more stable than a traditional kayak, especially not when there's a bit of sea. It's way too tall for my liking, that in itself (and in my mind) is making it inherently "instable".

To go back to my bike-allegory, a bike, when the wheels are parallel, are constantly out of balance, and the slower you go, the wider corrections are needed to keep it under you, until, at the extreme (a stand still), where you need to have the front wheel almost perpendicular, using both braking and accelaration to make the bike move back and forth beneath you.

Now, you may think that I'm taking this off-topic, but I'm not, I'm getting closer to your quote about the unicycle.

The difference between a unicycle and a normal bike, is that bicycle is that the ordinary bike will go faster, be more stable, is safer, and easier to use than the unicycle that need's to be constantly corrected, accelerated and deccelarated in two directions, often simultanously.

It's funny, though, that you bring up the unicycle, because that is sort of like my example of balancing on a stick, making it much harder to change course, and more importantly, the unicycle (read "the W-boat") is much more delcate on a rough surface (read "waves").

Now, the jumping part: The reason that it can be jumped with is because of the movement of mass, with your hips and legs using a platform to accelerate your upper body upwards with more speed/mass than your legs are weighing, hence you will jump. That has little to do with stability.

Why it hasn't anything to do with stability, or why I, personally, don't see it as such is because - well, let me start of a bit off-topic to set the scene:

I'm _still_ - at 33, pretty good on U-ramps. Both on BMX's and rollerskates and blades. I can (with a good three tries nowadays) still make a Mctwist (a saltomortale with a twist) on the blades, and I can still salto with the bike. And here's the catch: I can drive down the ramp on the rear wheel, I can jump on my front wheel, and on my blades I can do all sorts of tricks - jump and land on the front wheels alone after a 1080, and jump long and high, landing on one front and one rear wheel only (on the blades). Yet, it's definately not a stable set up. It doesn't take much to go wrong. (I'll skip the part with all my broken bones ...).

Speaking of which. A BMX, in itself, isn't very stable, and that's the point. It's short (making jump tricks easier (bigger height)), and the handle bars are wide (giving more torque when twisting it)).

Why do I use those examples? Well, because a) I can jump and do tricks on those contraptions just fine. b)Neither are stable per design, c) both demand much more than something low, and longer, and d) neither can seriously be used for the long haul, neither can they be considered to "easy" to use.

And just one other reason I brought those things up: you can jump on those as well, but that is simply a matter of shifting weight upwards, easily acheived on roller blades, and almost as easy on a bike (i.e. you have to lower the saddle). It doesn't say anything about the stability in itself.

Sorry about the length of this post :(

Andre

[icetreader]

Because of the higher centre of gravity, it's like sitting on top of ball, instead of in "the middle". I don't doubt your numbers or anything, I simply don't believe that it is any more stable than a traditional kayak,
Andre,

Beliefs can thrive in the absence of evidence, so let's talk about facts:

Show me people paddling standing in traditional kayaks...
Show me people fishing standing in traditional kayaks...
Show me people surfing standing in traditional kayaks...
Show me people jumping in traditional kayaks...
Show me people sailing standing in traditional kayaks...
Show me people paddling in the surf in parallel to incoming waves in traditional kayaks...
Show me people steering a kayak by leaning into the turn...

Regular people across the USA have been doing all these things and more with their W kayaks - There's nothing 'theoretical' or related to 'belief' about these proven facts.

Again, normally you don't 'sit on top' of a W but you ride it with most of your body weight resting on your feet below waterline while your legs are doing what they're good in doing: support and balance you.
It's a dynamic approach (reminding of canoes) while the approach in traditional kayaks is static - your legs are stuck forward and play a minimal role in your balancing, control and propulsion efforts.
More on these issues: http://www.wavewalk.com/PADDLING%20POSITIONS.html

Yoav

[DanishBagger]

That's not what I'm saying.

If you read my posts again, you would see that I point to the fact that it is indeed more stable relative to the surface, making it more unstable in the real world.

Why should I show you pictures of anything. You're the one that have the math calculated, you're the one that has a vested economical interest in selling your stuff.

Jumping, as I explained isn't that much of a deal, especially in flat water. I think I have already explained why. Several times.

Standing surfing? Has that to much to do with stability? Seriously, how stable is a semi-round-bottomed surfboard?

On another note, that "jumping" that is showing looks more like pushing the platform down, not actual jumping.

The people surfing in parallel? People do that all the time. And no matter how many tries it must have taken you, the problem of the inherent lift you have in two hulls will make one side lift faster than the other, simply because it's closer to the crest, so to speak. You can show me all those fancy videos. Just like I can show you fancy videos of people doing something else. That is not to say it is a good design because of it.

The fact is, no matter how math you give me, or try to make me show to you. You _do_ have a higher center of gravity, and you _do_ have the "lift" based on two hulls, making the CG describe a much wider arc when in waves coming from the side, hence it will have a bigger tendency to tip over sideways.

About people turning by leaning - that also has abosolutely zilch to do with seakeeping - A box, with the ends of the bottom turned upwards would do that no problem. Now, place a stool on top of that box to get the cg up higher, and call that more stable. I mean, you can "jump" in that box too, you now.

No matter if you prefer to call it "riding" it, or as I do "sitting on top", the difference is pure semantics. The only difference being that you have something _between_ your legs when riding, and when you sit, you can have your knees together.

Keep defending it. The thing is, that no matter what you say, your cg is higher, and it's more prone to tip over because of this and it's stability. THe stability is indeed stability in flat water, but I wouldn't trust it in any kind of sea, frankly.

[DanishBagger]

I forgot:

What happens if the paddler fell out un water over his head? That boat can carry an awful lot of water. How hard will it be to get back "on board" and get the water out?

Why isn't there a video of that?

Even if you believe in your kayak, it should still be prepared.

When the guy jumps, the hull seems to be twisting and flexing a lot. Does this lead to less stability?

Why is it the same person in all the videos. Why not an "every-day" paddler?


Edit: Apparently I forgot yet another thing. Because it turns when it is leaned relative to the surface, won't the kayak then have a tendency to go _up_ a wave when going paralel - making it even more likely to turn over?

[icetreader]

To go back in you practice a commom 'wet entry' (it's a padders' term) from the back. You can do it without assistance from other paddlers. Thanks to the boat's higher stability it's easier than getting back into a traditional kayak.

This model is molded from Polyethylene (like most kayaks), which gives a certain flex to the hull, and allows for extreme mechanical stress such as when a 200 lb (90 kg) person is jumping up and down in it or from side to side. It's not absolutely necessary but in this case it actually adds stability.

The photos and videos on the website show different people, including women and children - all amateurs. There isn't even a single photo or video of a professional paddler.

In lateral waves the W paddler leans into the wave and just keeps paddling (see videos) - Don't try this with a traditional kayak :)

[DanishBagger]

What about all my other questions, Ice?

[icetreader]

What about all my other questions, Ice?
You can keep paddling even with a few gallons of water in it.
If too much water gets inside you can take it out using a small bucket or a bilge pump - exactly like you'd do in a traditional kayak or canoe.
If you're close to shore (e.g. when surfing) you can pull the boat out and drain it by simply overturning it.
If you outfit the W with side floatation and you bail out on time chances are it won't even capsize:
http://www.wavewalk.com/Outfitting%20Your%20W%20boat.html
http://www.wavewalk.com/SURFING.html

[Deering]

Fellas,

As an interested observer in your discussion, let me weigh in since the fireworks have died down.

I am an experienced kayaker (by no means a "professional" but with many years of sea kayaing, and a bit of river kayaking in big water). I also own a larger power catamaran, and have studied cats fairly extensively. I'm an engineer, though don't claim to be a naval architect.

Both of you have valid points.

Bagger - your position that the VCG is higher is obviously correct. And all things being equal, higher VCG equals less stability. But all things ARE NOT equal. I think you are stating that the W kayak will ride parallel to the water surface at all times, so when encountering a steep enough wave on the beam the kayak will tip enough that the CG falls outside the footprint of the hull and capsize occurs. That would be a correct interpretation in an entirely static situation - if the rider was just a lump of clay that might happen, though it would have to be an awfully steep wave face.

In reality, the rider can have a major effect on the response to the wave simply by simply leaning into it, and that lean is made more effective by the fact that buoyancy is far outboard - the lean doesn't have to be very much to get the CG inside the footprint. Also, the hulls don't just ride on the surface - they sink into it which means that to some extent they keep the boat more plumb than the wave surface itself.

Would I paddle a W boat down the Grand Canyon? Not a chance, because I don't believe it can be rolled back upright (assuming an appropriate cockpit and spray skirt). And the "point of no return" will happen very abruptly. An experienced river kayaker can play with that tipping point to an amazing degree with a monokayak. But the W isn't targeted towards the Grand Canyon.

I think your perception of "top heaviness" is somewhat distorted by the fact that the boat is only 10 feet long. Stretch it out to a normal sea kayak length of say 17 feet (5-6m) and the proportions would look better, though still top heavy.

Your points have been argued ad nauseum about the big boats (catamarans vs monohulls), but tank testing has shown that in general cats are inherently far more stable and less likely to capsize in conditions that will tip a monohull.

The key advantages in my mind are faster displacement hulls due to higher L/B ratio, better initial stability, and greater rider comfort.

Yoav, Bagger raises some good points. And I have a few of my own.

The jumping stunt doesn't demonstrate much, and appears to have limited value in the real world. If I saw Bagger jumping on his skateboard I might be led to believe that a skateboard is a stable platform (it's not, proven by my recent unhappy experience on my nephew's).

The wet entry point is another good one. You should show that on your website. And why not put bulkheads or foam into the ends of the hulls to provide flotation? With that I would bet that a person could ride in it almost competely full of water.

I haven't paddled a W, but the appeal of paddling standing up doesn't resonate with me. What's the point? Do people do it a lot? Is it faster or more efficient? A catamaran gains its stability from the separation of the hulls. If the beam is being limited by retaining the ability to paddle standing, why not sacrifice that capability and get a wider, and significantly more stable boat in the seated position?

Your website makes a lot of comparisons with monohulls. If I had read your website starting paddling, I would have been sure that before going to my certain death I would have been cold and uncomfortable. Good for marketing, but not true!

I've spent many hundreds of hours in a kayak, and have never capsized. Where I paddle (SE Alaska) your kayak would be much colder and wetter. It's often chilly here, and it rains a lot. A monohull kayak has a nice snug cockpit with a sprayskirt to keep rain out. Your boat is exposed.

I fish out of my kayak - brought up a 250 lbs halibut a couple years ago. A W would have worked easier, but it's definitely feasible in a monokayak.

Your website articles make it sound like a monokayak requires constant vigilance to keep it upright. When I've fished I tether off my paddle and let it float with me, ignoring the conditions entirely. Sometimes it's been pretty rough but I don't even look at the waves. A well designed monokayak can handle some amazingly rough water without rider attention. I suspect a W would have been a rougher ride, though no less stable.

Yoav, an area you should market to is the boating community. Any boat that is too large to beach needs some sort of dinghy. Generally that means some sort of inflatable or rowing dinghy. Your boat will outperform any small rowing boat, and it has the stability and large cockpit to permit easy entry from a boat (I have standard kayaks for my boat and they require some gymnastices to get into safely). It's also small and light enough to be strapped to the roof. See if you can get into West Marine.

Enough babbling...

[bilgeboy]

Icetreader,

You are close by to me, and I would love to check out the operation one day. If you would like to give a tour, please send me an email.

Thanks,

Mike

[icetreader]

....That would be a correct interpretation in an entirely static situation - if the rider was just a lump of clay that might happen, though it would have to be an awfully steep wave face. In reality, the rider can have a major effect on the response to the wave simply by simply leaning into it, and that lean is made more effective by the fact that buoyancy is far outboard - the lean doesn't have to be very much to get the CG inside the footprint. Touche Deering! This goes directly to what I'm saying about 'micronautics' -the science :) of designing water crafts that are so small that a passenger can capsize them just by looking behind his shoulder...;)

Would I paddle a W boat down the Grand Canyon? Not a chance, Of course not, and neither would I.
However, it is possible to design a W Kayak with a slightly wider saddle and considerably wider hulls that would be much stabler than this first (rather narrow) commercial model and would make such venture as easy as rafting.
BTW, inflatable 'cat-yaks' have been used for whitewater paddling for decades.

The jumping stunt doesn't demonstrate much, and appears to have limited value in the real world. What's the real world?
Between us, isn't boatdesign.net almost entirely about toys? - Some of which are relatively small and inexpensive, and others are bigger and more expensive. You may not be impressed by this stunt and that's OK with me but many people find it exciting and 'useful' to stand in their small boat - whether it's for fishing, paddling or just stretching their limbs.

The wet entry point is another good one. You should show that on your website. And why not put bulkheads or foam into the ends of the hulls to provide flotation? With that I would bet that a person could ride in it almost competely full of water. Deering,
I've visited dozens of kayak manufacturers' websites and never saw a photo of a wet entry, although for most paddlers it's probably more practical than the eskimo roll. Why? -For the same reason car manufacturers show you pictures of airbags but not pictures of their product crushed or overturned.
As for foam bulkheads, we offer them as a standard option free of charge (check the 'Product Info' page). In addition, we offer three options of above-waterline side floatation kits that are much more useful since they can actually prevent water from getting inside the cockpit if the boat happens to lay on its side.

I haven't paddled a W, but the appeal of paddling standing up doesn't resonate with me. What's the point? Do people do it a lot? Is it faster or more efficient? Is skiing more fun than sledding? Some people would say it is and other would say it's not :)

A catamaran gains its stability from the separation of the hulls. If the beam is being limited by retaining the ability to paddle standing, why not sacrifice that capability and get a wider, and significantly more stable boat in the seated position? Why not indeed? It's possible to design W kayaks that are much more stable than the model featuring on WaveWalk's website.

Your website makes a lot of comparisons with monohulls. If I had read your website starting paddling, I would have been sure that before going to my certain death I would have been cold and uncomfortable. Good for marketing, but not true! Statistics show that the great majority of kayakers prefer to paddle wide, 'recreational' kayaks and not the long and skinny 'classic' models.

I've spent many hundreds of hours in a kayak, and have never capsized. Where I paddle (SE Alaska) your kayak would be much colder and wetter. It's often chilly here, and it rains a lot. A monohull kayak has a nice snug cockpit with a sprayskirt to keep rain out. Your boat is exposed. And how much time did you spend in a W kayak? :)
I weigh 200 lb and when I paddle a W Kayak I have 14" of freeboard. How much freeboard do you have in your monokayak?
I W surf in New Hampshire and paddle in the winter on partly forzen rivers and never felt the need for a spray skirt, but if someone felt the need for one I'd say 'why not? -go ahead and use one in your W Kayak!'

I fish out of my kayak - brought up a 250 lbs halibut a couple years ago. A W would have worked easier, but it's definitely feasible in a monokayak. Kayak fishing is an idea I really like, and fishing from monokayaks is indeed feasible, but not much more... In order for such an activity to be 'fun' for most people it should also be simple, easy and practiced in relative comfort, which monokayaks can't offer for most people.

Yoav, an area you should market to is the boating community. Any boat that is too large to beach needs some sort of dinghy. Generally that means some sort of inflatable or rowing dinghy. Your boat will outperform any small rowing boat, and it has the stability and large cockpit to permit easy entry from a boat (I have standard kayaks for my boat and they require some gymnastices to get into safely). It's also small and light enough to be strapped to the roof. I agree.
The truth is that I find it difficult to focus in one direction with this product since it already offers an unusually wide range of applications.
This is one of the reasons I'm participating in these forums: I'd like to see more boat designers (kayaks, canoes, cats, dinghies, moths etc.) take this W technology to new directions and develop new solutions in their respective fields.
I'm offering some ideas in my boatdesign.net design gallery and on this page: http://www.wavewalk.com/BOAT%20DESIGN%20GALLERY.html

Yoav

[Deering]

What's the real world? Between us, isn't boatdesign.net almost entirely about toys? - Some of which are relatively small and inexpensive, and others are bigger and more expensive.

Good response. I can't argue with that one.

I've visited dozens of kayak manufacturers' websites and never saw a photo of a wet entry, although for most paddlers it's probably more practical than the eskimo roll. Why? -For the same reason car manufacturers show you pictures of airbags but not pictures of their product crushed or overturned.

True, most manufacturers don't show wet entries, but the valid assumption is that most of the people researching their products are familiar with the reentry or roll processes - that process is essentially the same for all kayaks and can be readily learned from classes and books and web sites. You offer a unique product and therefore can't make that same assumption. I find wet entry a fairly difficult exercise on most kayaks - if your boat makes that process simpler (which I believe it would) then it might be valuable to exemplify that on your website, perhaps comparing a monokayak side by side.

Is skiing more fun than sledding? Some people would say it is and other would say it's not

Can't say - I snowboard. Different strokes. But my question was: is paddling from the standing position more efficient or provides other mechanical advantages than sitting?

It's possible to design W kayaks that are much more stable than the model featuring on WaveWalk's website.

What do you think is the maximum practical beam before seat width and paddle reach make it impractical?

Statistics show that the great majority of kayakers prefer to paddle wide, 'recreational' kayaks and not the long and skinny 'classic' models.

Which statistics would those be? Based on the number/types of kayaks sold? That's deceptive since the short, recreational kayaks are far cheaper and readily available at various outlets. Basing on that statistic only suggests that people prefer cheap & convenient kayaks. That being said, I won't disagree that there are a lot of recreational boats around. I've owned several - used them as dinghies from my big boat, mainly because they're shorter for stowage, have larger cockpits for entry, and have greater initial stability for entry from a boat which can be awkward. But most of them performed abysmally compared to my traditional kayaks. Hence my interest in W.

I weigh 200 lb and when I paddle a W Kayak I have 14" of freeboard. How much freeboard do you have in your monokayak?

Up here freeboard isn't the issue so much as rain protection. A spray skirt would be highly desired, or wear rubber clothes.

Kayak fishing is an idea I really like, and fishing from monokayaks is indeed feasible, but not much more... In order for such an activity to be 'fun' for most people it should also be simple, easy and practiced in relative comfort, which monokayaks can't offer for most people.

What's "fun"? Sledding is arguably easier, more convenient and comfortable than skiing...:rolleyes:

This is one of the reasons I'm participating in these forums: I'd like to see more boat designers (kayaks, canoes, cats, dinghies, moths etc.) take this W technology to new directions and develop new solutions in their respective fields.

When I finish my current boat building project I'd be interested in building a variation of your concept. Not with any money-making intentions but for personal use and to test some ideas. I'd happily share results with you. Thoughts?

[icetreader]

is paddling from the standing position more efficient or provides other mechanical advantages than sitting? The answer is rather complex and discussed here: http://www.wavewalk.com/PADDLING%20POSITIONS.html

What do you think is the maximum practical beam before seat width and paddle reach make it impractical? That would depend on the paddler's height and built, and on the application.
I'd say that for a 6' paddler a 30" beam is probably still good for efficient power paddling.

That's deceptive since the short, recreational kayaks are far cheaper and readily available at various outlets. Most manufacturers who offer low cost plastic, 'chubby' recreational kayaks offer low cost 'skinny' and long models as well. The difference in the cost of production of such models is not very big.
99% of people who paddle kayaks (i.e. kayakers) can't roll a kayak and won't even consider trying to learn it. Out of the remaining 1% who know how to roll a kayak not all can really depend on their roll in real-life conditions.
Also, few kayakers can get back into their boats without any help.

When I finish my current boat building project I'd be interested in building a variation of your concept. Not with any money-making intentions but for personal use and to test some ideas. What ideas? I hope it's not trying the eskimo roll on the boat :D

Yoav

[DanishBagger]

Most manufacturers who offer low cost plastic, 'chubby' recreational kayaks offer low cost 'skinny' and long models as well.

The difference in the cost of production of such models is not very big.


That doesn't address the question. It doesn't matter if the expense is the same - it's what they can be sold for.


99% of people who paddle kayaks (i.e. kayakers) can't roll a kayak and won't even consider trying to learn it. Out of the remaining 1% who know how to roll a kayak not all can really depend on their roll in real-life conditions.

95 percent of all statistics are made up on the spot ;)

Anyways, at least here, the few people I know that kayak, has to be able to make an eskimo-roll in order to join a club. If they can't, they get a course to begin with. Now, I'm not saying that everyone is in a club, nor am I saying that my "statistic" will hold true anywhere in the world, I'm merely pointing out, that that "statistic" isn't true here, and that you seem to have a lot of "science" and "statistics" where you quote yourself. That isn't science, that is marketing claims.

Andre

[JEM]

friendly discussion?

[DanishBagger]

Andre,

Now that you're saying that you've already paddled a kayak I'm thinking that maybe I should have attributed more weight to your comments.
I am also willing to admit that perhaps I should have tried harder to understand your sense of humor, but it looks like now I have lost you completely.

Since I believe that I'll be able to overcome this loss I'd like to thank you for taking the time to participate in this thread.

Sincerely,

Yoav

You still don't, or won't, get it, huh?

You putting me down because I'm not an avid kayak fan, has little bearing on whether my point was made in that post. Which it was. Read it again, maybe you will understand - or perhaps that is the very reason you have begun playing it down. Even if you were a pro paddler, so to speak, doesn't mean you get to make arguments that are free fantasy, making statistic statements pulled out your rear, nor that you are _the_ know-it-all über alles.

Your sarcasm is having a hard time hiding your lack of arguments.


Where is the statistics pulled from? Show me, because your three recent post has been feeble attempts to not show that you did indeed pull them out your arse, like I did with the 95 percent.


Edited (something was missing).

[DanishBagger]

Hmm, still the dodging.

a) Anyone on these forums, that have tried your kayak?

b) where's the real statistics showing that a mere one percent can do a greenland-roll?

[DanishBagger]

Did some posts go missing? This thread was more thna four pages at one time, now it's three.

[Jeff]

Yes - I removed several posts that seemed extremely hostile and which I did not believe contained any information -- I really hate to have to be a heavy-handed moderator, but I think it's important to maintain a friendly environment to discuss ideas and not a place for personal attacks.

Over a dozen members who have contributed a lot of valuable information to the forums have brought to my attention the fact that a few posters have made the forums much more unfriendly in the last month or so with unneeded jabs and personal attacks against other members. Thus I feel the need to moderate a bit. If a post contains interesting on-topic information, I will never touch it. If however a post is simply repeating the same thing over and over and over, or attacking another person's reputation, I believe it is in the interest of the forum to delete these and maintain a friendly atmosophere and to keep the focus on ideas.

[DanishBagger]

Ah, okay, Jeff, I was just wondering. Thanks :)

[ancient kayaker]

Wasn't able to access the patent but main features evident are increased stability due to twin hull and lowered CoG due to feet on bottom of hulls. Short so emphasis fun not performance, highly manouverable. Would have more draft and drag than comparable conventional kayak, not for the flat water lake paddler like me, meeting a submerged log or exploring shallow water could cause problems. This is a whole new class of kayak and could catch on; who knows where it could lead?

[Toot]

Wasn't able to access the patent but main features evident are increased stability due to twin hull and lowered CoG due to feet on bottom of hulls.

I keep hearing people say this and I guess I need it explained to me.

Imagine I push two sections of 3-foot long PVC pipe (with an end cap) down through the bottom of the kayak, and then insert 20-foot tall stilts into that pipe, such that they stick up 17 feet in the air...

I then hop on those stilts and start to paddle along with ridiculously long paddles. Is my Center of Gravity 3 feet under the boat? Or 17+ feet above it?

I think the latter... some of you think otherwise?



Sure, my stilt-boat will have great static stability. But the polar moment of inertia is going to make turns a *very* dicey situation. Dynamic stability is going to be a PITA... sort of like the difference between stopping a spinning barbell, versus stopping a spinning bowling ball with a long rod stuck through it. It's not just the Center of Gravity, it's the polar moment of inertia caused by the distance between the CoG and the weights. In other words, there's a reason why high-wire artists use long heavy poles instead of carrying bowling balls as they try to walk across a skinny wire. It's the reason why Porsches have a bad habit of spinning with little warning, but offer unparalleled turn-in on a slalom course.

Your CoG is located somewhere around your belly-button. And it's around your belly-button regardless of where your feet are located. What the W boat has is a higher polar moment along its vertical axis. This will make it more resistant to capsizing.. because, like stationary barbell, getting it to start spinning (along the longitudinal axis) will be more difficult... but once it starts to go, it becomes like a spinning barbell... it'll be hard to stop! By contrast, the traditional kayak with a low polar moment, will feel very "tippy" because the bulk of its weight is focused very close to the CoG... just like a bowling ball that's easy to start spinning in one direction, and then in the other... but the lower polar moment means it requires little effort to shift from leaning on one side, to leaning on the other.

The W boat undoubtedly offers better stability... the cost of this is less maneuverability. You can't argue otherwise... these two are opposites in vehicle dynamics. This *may* be offset (to a degree), however, by the enhanced ability of the pilot/paddler to shift his weight to a greater degree while standing up. Nevertheless, this could also be a problem, as a pilot/paddler drastically out of position may be opening himself up to a much more dramatic splash or even injury... For example, I'd hate to be standing upright, leaning the boat to the left in an effort to keep it upright, while a wave pushes it over, capsizing it to the right. The whiplash could cause a most uncomfortable situation.... I think I'd have ice and heat packs on my back for a week after that! But, again, the boat is highly stable, so this scenario isn't nearly as likely as it would be if you were, say, trying the same stunt in a kayak.

Anyway... the claim that your CoG is where your foot falls is just flat out wrong. It's at your belly button.

[Poida]

Icetreader

Best o' luck with your boat. This is probably not the best forum to introduce it to because of all the suedo geeks that want to put their cents worth in and knock what is probably going to be a very marketable product.

It looks like an excellent craft for the guy that is sick of trying to cast 50 metres (or whatever in feet) off the shore but can paddle out and fish off what appears to be an excellent fishing platform.

Looks like maybe enough room there for some scuba gear.

I heard, in relation to marketing, when someone said McDonalds make the worst hamburgers in the world, but sell the most. The people who buy your boat probably don't know what the centre of gravity means. They just see themselves paddling offshore in a craft that has enough room for fishing tackle even flares and a marine radio.

Marketing can go wrong tho' sometimes the message you are trying to send out isn't the message that people receive. I was told in marketing you have to assume that people are idiots.

It might be an idea to separate your website into different websites ie fishing, surfing, family fun etc. as it appears that the general comments that have come from this forum is that someone would take out into the ocean with their fishing gear see a big wave and think, "why don't I stand up and get knocked arse over tit?" Although you are only demonstrating stability by standing up in a wave it seems to have confused people.

I reckon a fun sport would be to have josting competitions, two people standing up in the boats trying to knock each other off with their paddles.

Enough from me
Once again
Best o' luck