Mud and the Tender

So long as you don't have to go to far or fast, some variation of this design should meet most of your requirements: http://www.aqua-cycle.com/

Slightly larger design will hold 3, add quick release wheels and folding frame?

Also, kinetic sculpture race vehicles for ideas on building:

http://en.wikipedia.org/wiki/Kinetic_sculpture_race

Cheers,

Porta

 

I have been high and dry many times . Returning to the dinghy to find it in the mud and the locals queuing up for a laugh. There laughs turned to dismay as they got out their mobile phones to take a picture of a guy rowing through mud.

Now its not easy but having people laugh at you gives you super human strength. A sharp jab with the oar to get it into the mud and pull as much as you can without breaking the rowlocks and a quick snatch of the but on the seat to --un stick it from the mud and she will move.

Ok I was sweating a bit when I reached water but it shut the audience up and better that waitng 4 hours.

I hate tides, they go out and then come in again , and when it comes in it then goes out again and then guess what yeah it goes out again.

 

The object is to get to the boat moored out in the water.





I'm not sure about getting back to land.

.

 

Frosty and Porta - you guys have hit the nail on the head.

This is indeed the way to go.

A combination of both these technologies makes sense inside my warped head. I am particularly in favor of doing something that incorporates the oars, as there are many times when the boat will be in the transition phase, half in water and half in mud, so that some pressure on the water for forward propulsion, combined with some 'direct drive' from a paddlewheel arrangement will also be required.

These combined forces may be encountered two or three times per trip in crossing mini mud bars, and for the rower to simply maintain the same steady motion with oars, appears to me as the least troublesome method. Especially in any kind of wind.

The paddlewheels by themselves in water (I know from personal experience), make for very inefficient propulsion, particularly in any kind of wave and/or wind action. To row conventionally has to be a real option for this 'vapourware' concept, but to my mind we cannot ignore the benefits of a 'direct drive' of a paddlewheel of some sort to get across 'dry water'.

If we can have a hull that will support a sail arrangement and a small motor as well, I think we are looking at the ultimate tender.


As an aside, I was chatting with a large catamaran owner the other week, and he was telling me how he was building a small sailing dinghy to act as his tender. He told the story of being anchored of a small, attractive island in the middle of the ocean. At that point he only had the traditional rubber ducky with an outboard.

He was tempted to visit the island across a fairly brisk gusty wind, but he pictured his predicament if the outboard died half way between his boat and the island. He would certainly just get blown out to sea. Having a sail would make the trip a lot less perilous.

 

Getting in/out of a dingy arrangement without marinating in mud would be an issue. So something that can roll in/out from non-mud conditions would be better, seems to me. Here's one that could be possibly fit with oars, a sail, or even a motor: http://www.autocanoe.com/ Made to pedal distances around town also, so the paddlewheels might have to be altered.

There are some very fast paddle wheel designs that rival props in speed and efficiency both human and motor powered. Clementine example: http://www.humanpoweredboats.com/Photos/UniversityDisplacementHPBs/UniversityDisplacementHPBs.htm



Porta

 

I have seen that one several times before, and it looks like it will have a lot of relevance.

In my mind, I will need to dummy up a full size rig, and test it.

The biggest decision is whether to try for pedal power, or rowing power. Both have their pros and cons.

 

Have you seen the pedestrian operatated paddy field tractor ie a tractor for plowing rice field. Its not exactly mud but the wheels might be interesting to you.

 

Is this the tractor to which you refer? http://www.youtube.com/watch?v=9Gx0RRT_g2E

Or this? http://www.youtube.com/watch?v=hFUep29O8_g&feature=related

 

i'd go for pedal powered with a "propulsion system" you actually find in those pedaling pleasure thingys...

although my favorite is still the hovercraft... i want me one of those:
http://tech.slashdot.org/story/12/0...ts-to-show-successful-hover-bike-test-flights

 

Thanks to Rick Wlilloughby, I know where to get the pedal mechanism from industrial suppliers.

I think we will need to keep the oars though. Its hard to best them for maneuvering on water. I cant see pedaling and rowing at the same time being very easy - not like walking or chewing gum.

I keep trying to imagine the rowing cycle driving some kind of paddlewheel - would you get a full circle, or half a circle ... I can feel a mockup coming on !!

 

How deep is the water? If less than 4-5 feet, then a good old used high-wheel tractor would be cheapest/easiest solution.

If the water is deeper and you have a little more money to burn, then an Argo may be more suited to the task - just don't get in a big hurry. If you're in a hurry, then the 500hp airboat will do.

If the mooring and staging areas are permanent, you could build a couple of towers with a rope/cable suspended between, then pull your rowboat along that rope (more efficient than rowing through mud). Other option is the old clothesline on two wheels to pull you along either way, with a motor on one or both wheels.

If in a perpetually windy area, tie a kite to the bow to get additional lift and pull while rowing...

Maybe some variation of an iceboat drive wheel? see pic

 

Seems if you don't want to get muddy feet or clothes, some kind of wheels will be needed. You can incorporate both oars/kayak paddle, etc. and propulsion wheels without much difficulty. Both do not have to be used at the same time and can be rigged independently of each other. Hobie uses both flippers and then paddles for the shallows.

It would help to define the distance, speed and water conditions where this conveyance will be used and whether this will be a dedicated vehicle or take the place of a lifeboat (sails??), tender, etc. The simple water trike would work for the distance and protected conditions pictured in your original submission?

Porta

 

Could you repurpose four large fenders to become outrigger wheels when one reaches the mud flats? On a bracket to sweep them back against the hull when afloat again? Your dinghy might look like a 1/3 scale marina launch with them folded flush, and like a water bug when mud flat crossing. Especially with the oars flailing against the mud flat.

Structurally easiest to construct with an aluminum hull, I bet, as the point loads at the hinges would high.

You would have to figure out how to lean starboard to drop the port fender training wheels, and vice-versa. But it should be doable. And the result would be very stable on the mud or afloat- like a conventional dinghy with RIB "water wings".

 

Yes, very good point there Mr P.

In my ideal world, I would like to see this "thing" able to cope with a wide variety of conditions - not just a set scenario. Looking to general usage, not just a one off build.

The three basic scenarios perhaps -

Standard - Launch in the water, goto yacht in the water.

Half Mud - Launch in Mud, transfer to water, got yacht in water

Full Mud - full mud all the way from shore to yacht

Operating conditions - dead calm to say .3 metre waves and wind up to ~20 knots. Maximum sailing/rowing ~5 miles

I think Porta and Village have re-inforced the need for some wheeled assistance, and we just need to work out its configuration, to be operated manually. The problems of storage might make Fishes thoughts on inflatable devices has a lot of merit there. Its always a pain to inflate and deflate things.

Maybe some variation of 'beach wheels' ?

 

That canoe on bike wheels will never work, it would just be stuck in the mud. i like the idea of using the fenders as big fat wheels. the problem is the surface of the mud is too soft to carry highly loaded feet, narrow wheels, etc. So you need much more surface area, but the suction/drag would mean you just can not have a large flat bottom. Carrying very large wheels means extra bulk, but if the yacht is anchored, you will not need the fenders, so you mount them on the bottom of the dinghy, and row/pole your way to firm ground.

when at dock side, you will not need wheels on the dinghy, you use them as fenders. When you have a firm beach, you leave the fender/wheels on the boat and just row the dinghy to the beach or dock.