Stern Drive platforms???

[Cranky Janke]

Hey,

I'm new to this forum and I don't know anything about boats or boat engines.. however I'm an student-architect attempting to design floating platforms that connect two banks of the river Spree in Berlin. These platforms need to be able to move to allow for motor boat traffic and I'm wondering if Stern Drive platforms are an option? that could move and fit in together in clusters to allow for traffic.. and if this could/would determine the form of the platforms? for example if it being circular would effect its' movement as opposed to it being hexagonal or rectangular..? or if not Stern drive is there any other method I can use?

Sorry about the hundred questions!
any help would be GREATLY appreciated!

Cheers

[FMS]

Not likely a good option. Difficult to maintain over time and not optimised for maneuvering a barge at slow speed and tight quarters. What size are these barge platforms? Can you post a sketch of your idea? It would generate better comments.

[Cranky Janke]

Yeah so the idea is to have these floating barge platforms that connect the two banks. Preferably they can move and fit in together.. so they won't/can't necessarily be circular. or be connected by mini 'jettys' that connet them which can rotate and make way for traffic...? I know it sounds a bit far fetched but i'd like to give it a go if it can be done! haha

[Cranky Janke]

more like this maybe? or have jettys that can rotate and move out of the way might be a better idea..? but the river itself at where my site is, is only 62 metres from bank to bank so space is an issue..

[gonzo]

Outboards are the easiest solution. You can make the mount to turn so they can be used as thrusters.

[Cranky Janke]

Originally Posted by gonzo

Outboards are the easiest solution. You can make the mount to turn so they can be used as thrusters.

so that means I have to figure out a transom to mount the outboard on my platforms..? Can I for example steer hexagonal platforms? or will the platforms need a hull, bow and a stern to be able to manoeuvre them?

[Chase_B]

hmmm what about using one of the platforms as a primary,..with a compressor on board,..now at 2 opposing locations on each platform put air operated props on a 90 degree head that can rotate 360 continuously vertically,..this could also be controlled by air driven worm gears,.so you do not see any of the components above deck,..if your worried about noise from the air driven prop/ control head ..put a scavenge system to the exhaust side that returns back to the compressor tank via pump,..now your not only pushing the air thru the devices but also sucking it thru,..no cavitating bubbles that would create a problem for anything that floats on water. the primary float would control all the floats,..fueling only one source of power to manipulate as many floats as you want with in the CFM capability of the pump/system,..blow a hose? it's only air ..no contaminants.

just a thought

[gonzo]

We run platforms with rectangular and one with an odd hexagonal/oval shape. They were big enough for a Philarmonic orchestra each. The outboards were spaced on each corner, so the leverage for maneuvering was maximized. They were a pair of 140HP Nissan.

[Cranky Janke]

Originally Posted by Chase_B

hmmm what about using one of the platforms as a primary,..with a compressor on board,..now at 2 opposing locations on each platform put air operated props on a 90 degree head that can rotate 360 continuously vertically,..this could also be controlled by air driven worm gears,.so you do not see any of the components above deck,..if your worried about noise from the air driven prop/ control head ..put a scavenge system to the exhaust side that returns back to the compressor tank via pump,..now your not only pushing the air thru the devices but also sucking it thru,..no cavitating bubbles that would create a problem for anything that floats on water. the primary float would control all the floats,..fueling only one source of power to manipulate as many floats as you want with in the CFM capability of the pump/system,..blow a hose? it's only air ..no contaminants.

just a thought

That sounds quite interesting... Like I said I don't really know much about boats.. is there a diagram you can show me? or maybe a website that I can demonstrate how this would work, please? It would be the biggest help!

[Cranky Janke]

Originally Posted by gonzo

We run platforms with rectangular and one with an odd hexagonal/oval shape. They were big enough for a Philarmonic orchestra each. The outboards were spaced on each corner, so the leverage for maneuvering was maximized. They were a pair of 140HP Nissan.

@gonzo: you said 'we run platforms?' do you have a website?.. or images so I can have a look at this?

[Chase_B]

Originally Posted by Cranky Janke

That sounds quite interesting... Like I said I don't really know much about boats.. is there a diagram you can show me? or maybe a website that I can demonstrate how this would work, please? It would be the biggest help!

sorry ,..I don't have any diagrams ,..it was off the top of my head,..just a thought that I know would work,..and only take one operator to maneuver all the floats,..the trick would be to orchestrate each "head" at required rpm to smoothly move each float,..taking in concideration of weight,..directional flow of the river, speed of that flow,.. to nuetralize the motion of the floats in relation to the shore,.. I am assuming that part of these floats will be attached to the shore line or anchored in some way,.. so either a series of anchors or a way to neutralize the flow of the water would have to be addressed

[Stumble]

Take a look at http://en.wikipedia.org/wiki/Voith_Schneider_propeller I don't know a lot about them, but they eliminate the need for a transom and mounting hardware. Of course the control over the drive does raise other issues.

[keysdisease]

I have seen something similar to what you describe at the Ft Lauderdale Boat Show that "opens" a section of walkway to allow boat traffic to pass. Its hinged and a outboard just rotates a section of this floating dock 90 degrees .

A fixed hinge point will reduce operator error, the "gate" will never "get away' and there will be minimal skill necessary to operate.

At 60m I would think 20m of fixed floating sections from either bank and a 20m section in the middle that would be "hinged" at one corner to the corresponding corner of one of the fixed sections.

Another nice thing about this arrangement is that if the engine won't start the "bridge" could be opened by just allowing the current to "open it."

Steve

[Chase_B]

ok so both ends are attached to the shore/ apposing shores ,.a floating gate is what your looking for lots of choices there to power the gate,..hand cranks with cables or winches,.to motors,..as keysdisease had mentioned .the flow of the river can be the power source for one way ,.. my concern then would be the span versus the speed of the rivers current

[keysdisease]

Various types of floating bridges have been used over the centuries. Military bridges are some of the more thought out units:

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

Some very unique ideas here:

http://le-revolution.blogspot.com/20...that-made.html

and here's a company that makes what looks like a very nice unit:

http://www.superdecksystems.com/float_boardwalk.htm

What may dive many decisions abou what you want to do is who is going to use this bridge? Just foot traffic, motorcycles and scooters, cars, trucks?

Will it be open to the public? Liability?

Steve