# Wave force induced power proa magnetic propulsion

Discussion in 'Propulsion' started by AAn, Sep 3, 2020.

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1. Joined: Sep 2020
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### AAnJunior Member

Kind regards, happy boaters!

I want to start a topic on wave force induced propulsion.

Brief intro:
I have been reading and enjoying this resourceful net place for a few decades ;-)
It is fair and straightforward to say that www.boatdesign.net immense knowledge and experience have built up my theoretical boating basics, which I am happy to use.
Also, I was tracking some progress in permanent magnetic motoring movement as well.

And so.
In my unscientific view there is a possible way to use ocean wave force to actuate permanent magnet poles attraction and repulsion forces. Like in Howard Johnson magnetic motor idea where the actuator magnet sits angled with its south pole in a steel shoe (it seems to be hinged on an axis) and there are angled magnets on a rotor as well. When the shoe with an actuator magnet moves the magnet north closer to rotor, the north repels the north of the angled rotor magnet nearby thus rotation. When the shoe (magnets south) moves back and gets closer to a rotor then south attracts the north of the next magnet on a rotor simultaneously breaking away from the previous rotor magnet. Push pull so to say.
Simple principle. Already checked it using broken hardrive tiny magnets. It works.
And it does not take much power to rock the shoe axle shaft back and forth. In return, neodimium magnet attraction-repulsion forces are huge and can be dozens of kilos depending on magnet weights. Which, with a stack of rotors on a rotor shaft, can scale up to a normal-size jet ski ICE engine torque.

In some previous wave propulsion discussion I noted a force calculation for a wave with a period of 6 seconds acting on a float of 250 gal / 1000 L volume leveraged at 1 m distance. It came down to about 1,6 kW per second or 10 kW per 6 seconds. That is a lot of still wasted power... (In that way coastal boats can harvest more wave power than offshore boats as coastal wave periods are shorter and doldrums are scarce near landmasses ))

Now we have power expectations explessed in kW. So far so good.
Next is to prepare the setup to convert float(s) wave induced oscillation power to more kWs.

Setup: I have grown up biased toward Pacific Flying Proas of the Jzero / Madness breed so there was hardly any choice for me. They are just beautiful in my eye. Not perfect in some respects but real cute overall. I am happy just staring at them.))
Outrigger float will need to be extended to mainhull length and made up of three 10ft sections articulating on hinges. That makes for two hinged connections, allowing to takeoff wave power. The outrigger sections connections to beams will need to be articulated as well, again allowing for two more power takeoff joints.
Referring to previous power expectations, I am hopeful to make up to 4 kW force accessible.

It is time to get to mechanical implementation part. In terms of efficiency, mechanical power takeoff/conversion is better because of little losses. Hydrostatic power takeoff offers much freedom in pumps and motors locations but brings in more weight, power losses and complexity. So let us begin with simple mechanical power takeoffs.
Due to hinged joints push-pull movements it is possible to use levers at both ends of joints connected to each other with endless ropes wound around the drums. Both sides of drums there are one-way clutches attached to flexible shafts like they use for vibrating concrete slurry in construction. Thus each power takeoff joint provides two counterrotating shafts. The flexible shafts go to a pair of counterrotating permanent magnet rotary motors, possibly intermeshed with gear wheels and rotating a driveshaft of a sports bike gearbox used as an rpm multiplier.
The gearbox primary gear attached to a jet ski impeller shaft.
Maybe we shall need even more rpm multiplication here just to get in the middle of specific jet drive efficient rpm.
The gearbox additionally provides a neutral position which is good for safety.
The outrigger floats sections surely need provisions to latch lock the motion. Say for overnight anchorage.
The jet ski hull parked somewhere in the middle under the beams. Attachment is better be hinged in order to track the waves and also 360 degrees rotatable to allow for vectored thrust.
Wake wave interaction of all three hulls will need to be researched for some acceptable compromise.

Power estimate (wild guess way): as I have found out in Toyota Prius permanent magnet motor-generator tinkerer circles, the power can be related to permanent magnet total mass. So if we use the same mass of permagnets in our rotary motors as in Prius MG2 (the larger one) then we can make close to same 50 kW work done and similar (tremendous) torque which is more important to us.

Due to ocean waves intermittent motion, it is expected and recognised that the simplest form of implementation of the above will get us intermittent pulsing propulsion. If we feel OK to simplify even further, then yuloh oars can be used instead of a jet ski. Then we will need to reverse connect our gearbox to demultiply the rpm and provide means for a reciprocating motion to drive the yulohs.

If we are happier with jet ski drive relative safety for marine life forms, then there is a possible way to make things more involved and complicated. We may have to cobble up an acceptably heavy gyroscope/flywheel energy accumulator in pretty much the same way the magnetic drive motors were proposed. Just keep it on magnetic bearings and within the vacuum chamber.
Then no more pulsing and constant rotation.

More power and speed: to get more, it is possible to attach even more floats/sections at bows and sterns of mainhull and outriggers increasing the number of power takeoff joints/levers.
There is another wild guess that this may allow to drive an air cushion fan and to convert the the Jzero/Madness into a hovercraft with jet propulsion. It is going to be very fast if we will not back off in power. Sevtec's Explorer hovercraft is close in weight to Madness, so its low-pressure cushion type, area and volume can be used as a reference.

Additional benefits: if we install an air screw propulsor similar to Sevtec Explorer in the back, we can admire amphibious qualities of Jzero/Madness air cushion magnetic drive power proa.
For this purpose we shall need an auxiliary power to oscillate our actuator magnet shafts when on a beach. Or in doldrums.
Environmentally minded and renewable resources thoughtful may choose to use steam power for that. It is silent as well. WWII era charcoal gasifier may provide volatile gases mixture to fire up a steam generator. British hydroplane world provides a solution: drawings of Robert Kirtley hydroplane steam motor and steam generator. Very small and powerful enough to drive the PM actuators.
Charcoal is lightweight and can be stored within outrigger floats.

Base Madness proa mods I consider:
increase pod height for more headroom;
Increase pod length for more room and to move the outrigger beams further apart since the beams will need to be attached to outrigger articulating front and rear floats.
Use freestanding (maybe running endless front/backstay) AeroJunk rig on a tabernacle for lowering when running under power. Tabernacle to be stepped where the pod entry hatch is now, for more bury and support;
Pod cabin entry hatch relocated accordingly;
Present "sidecar" gets enclosed and becomes part of the cabin - which allows space for some galley and stores;
The pod cabin elongated further toward the outrigger, maybe halfway the current beams length - this will allow for a larger cockpit;
Mainhull and outrigger underwater lines - I would love to experiment with wave-following Erbil Serter hull lines since now we need to follow wave motion. In displacement mode Serter lines, concave rocker line(?), allow to implement air cavern principle. Air cavern is a next big thing in our Navy mosquito fleet. ;
As for rudders I would rather choose Rob Denney kickup rudders;
Mainhull and outriggers to be converted to SOF skin-on-frame structures. Faster build, lighter weight. More expensive, since puncture/rip resistance can be provided only with layers of UHMWPE fabric like in bulletproof vests now;
The magdrives can drive a fridge, an aircon, watermaker, generator and whatnot, if the wave action is good enough ;-) The question how to squeeze all those inside..
Well, now the Madness proa is no more like the original, looks more like a Sidecar proa without its sail rig... Add to this the bag skirts all around, outrigger floats going up and down, flexible shafts dangling from rocking levers, Multiwing fan, jet ski and pusher prop in a duct.. Oh, well... That is the cost of freebees.

I welcome positive response to my proposal.) Will be grateful for engineering minds' feedback regarding wave power kW estimate. The proa "wave train" of two proas chained together, can this triple the power takeoff estimate? The sought after 50 kW magnet motors output was based on an output torque figures for a jet ski ICE engine and Prius larger motor-generator. As I have found the jet skis embedded into power boat hulls propel the resulting power boat at more than 20 kts with a displacement of 2000 lbs. If we can peruse an air cavern or if we can get hovercrafting (airborne to be wild)) then the speed potential of a twin-hull train minimal accomodation ocean crosser gets very interesting. And we get free power, aircon, fridge.
What do you think, fellow boaters, like it?

Will Gilmore likes this.
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### AAnJunior Member

There is an option: the hulls can be built in articulated sections also, increasing the number of wave power takeoff joints. Which will further increase power potential.
There should be some balanced equilibrium point.
If we get a lot of propellant power it may call for suspension seats and suspension bunks.

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### AAnJunior Member

Regarding the sailing rig: it gets to be an auxiliary propelling means so accordingly stays folded most of the time.

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### AAnJunior Member

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### Will GilmoreSenior Member

Check out the mechanism used in the old self-winding watches. There is a lot of potential for taking wave power in those.

-Will (Dragonfly)

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### AAnJunior Member

This is a brilliant idea.

Will Gilmore likes this.

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### Will GilmoreSenior Member

-Will (Dragonfly)

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