pedal power

[GJB]

Hi every one, I am trying to put together a "design" for a ecological boat.

 

The building material will be recycled wood, (from any breakers yard) the boat will be cross planked and the layers will be glued together with homemade liquid cement, which is a simple mix of waterglass, shellac resin and water.

 

The design will very much look like this one:

 

http://www.mission-b...skiffcycle.html

 

 

 

So yes you guessed it right it will be pedal powered.

 

 

 

The whole thing will be painted with natural linseed oil based paint.

 

 

 

Now back to the "power system", I have always wondered why all PPS

 

( my abbreviation for Padel Power System) are always just based on bike pedals, the torque arm (if such a term excists), is very short.

 

 

 

What I would like to know is would it be a good idea to create a setup with a long and a short end (please excuse my lousy explanation) like in a hydraulic hand pump

 

 

 

 

 

This lousy drawing will have to explain it all(sorry)

 

 

 

The small circle is any engine block from any kind of small engine 2-cyl is best I think (you can put both your feet to work), so the vertical movement is defined by the stroke of the engine. Let's assume that the stroke is 5 centimeters the paddle end of (the long end) will move up and down 50 centimeters. So little effort is needed to make the thing turn round. The big circle is a flywheel that connects with a V-belt to a car dynamo, which in turn will charge a battery.

 

 

 

The actual propulsion is by electric outboard motor.

 

 

 

The advantages of this setup are:

 

 

 

1) High power output with little effort (at least that's what I hope for)

 

2) Separate battery charging and boat propulsion. Like when you're at anchor and fishing you can still charge the batteries.

 

3) It would be a very green solution.

 

 

 

Is this doable or is this just plain crazy?

 

 

 

What do you think?

 

 

 

Cheers

 

GJB

[CaptainPanic]

Your legs are the most efficient when they go from a (about) 90 degree angle at the knee to an (almost) full stretch.

Bike pedals are built to fit that motion.

 

You are completely correct that the torque does not always match the application, which is why a bike has gears. Your 'invention' is just a complicated way to replicate what gears do.

 

You should see at what frequency the generator should run (it might be more efficient at a certain range of rpm values), and add some gears to achieve that, so that you can bike with a comfortably pace. So, your 'invention' is just making something simple a lot more complicated. Stick with the existing technology... it works, and you can just use existing stuff from bikes.

 

Regarding the power: You are typically looking at a continuous output of about 200W (Sorry, i had to add this (on-topic) picture of Lance Armstrong ). This is an order of magnitude - Tour de France cyclists can achieve more, especially in short bursts such as a sprint... if you're thinking about charging the battery and then chill out, this figure will obviously be a lot lower. And frankly, 200 W is not much for a boat.

 

To put this into perspective, 200 W is about 0.27 horsepower... and I cannot find a single outboard engine of such a lower power. In other words: you're not gonna be fast. But it will work.

Edited October 24, 2011 by CaptainPanic

[GJB]

Thank you for your reply,

 

I was almost sure that my plan sucked somehow

 

I think I will spend a lot of time browsing around for discussions about pedal power.

 

Maybe it's an idea to have an all mechanical set up with side paddle wheels like mississippi steamboat ?

 

Cheers

 

GJB

[insane_alien]

Thank you for your reply,

 

I was almost sure that my plan sucked somehow

 

I think I will spend a lot of time browsing around for discussions about pedal power.

 

Maybe it's an idea to have an all mechanical set up with side paddle wheels like mississippi steamboat ?

 

Cheers

 

GJB

 

reinventing the pedalo are we?

[CaptainPanic]

Thank you for your reply,

 

I was almost sure that my plan sucked somehow

 

I think I will spend a lot of time browsing around for discussions about pedal power.

 

Maybe it's an idea to have an all mechanical set up with side paddle wheels like mississippi steamboat ?

 

Cheers

 

GJB

I don't know what is easier... most pedal boats are all mechanical, so there is definitely nothing wrong with an all-mechanical setup. The difficulty with all mechanical is obviously to transfer the mechanical energy from inside the boat (where your pedals are) to the outside where the propellor or the paddles are. This might actually be harder than it seems, because you need to keep the water out.

 

But the charm of your idea is that you can pedal when you feel like it, and you have power at your disposal at a different moment. All I wanted to say when I talked about the power is that you're looking at something equivalent to sports, not chilling out. If you make your boat streamlined, you can achieve decent speeds. And even the smallest engines cannot run all the time: you need to cycle maybe 2 minutes to run the engine for 1 minute.

 

All I am saying is that you should use regular gears (whatever you do). Using a regular (small) outboard engine, and a battery system from any wind/solar power pack, you should be fine. Make sure it has the same voltage as your engine. These things exist already, often for on boats or campers/caravans, so you don't need to design anything. They are already suited for a variable power input (like from a small wind turbine). Then all you need to do is hook up the generator.

 

Alternatively, if you go for all mechanical, then at least add some gears. One thing I hate about every (touristic) pedal boat is that it's set up for really low speeds, so as soon as you get going your pedal speed is so high that it becomes a limiting factor.

[GJB]

Captainpanic,

sur electric outboard that are on the market can run longer than that?

 

And I forgot to say that I,m no speed freek pottering along at 2 or 3 mph on a small lake or for example the French Canal du Midi would be great for me.

Nor was I very clear in what I exactly wanted. Let's first throw this contraption of mine in the dumpster, and follow the wind/solar power pack method.

 

What I envision is this: A store bought electric motor moves the boat while the helmsman is pedalling away to charge the battery,( or if that's a bad idea he could charge the spare battery. For example I will take a 2hp Torqeedo, (2hp= 1500 Watt?), while the helmsman is pedalling 200W. Which is 7.5 times less.

So in fact the first thing I will achieve is some more sailing time. In Europe many people just take short trips. And if I keep pedalling while at anchor I will gain some more sailing time. And i like your idea of solar power, that could be added in the mix since the type of boater for this type of watersport will be your typical "nice weather sailor". I have to look for this solar cell foil that's supposed to be on the market, maybe it will produce another 200W when I cover the cabin roof with it.

 

Again thanks for your input I might be getting somewhere

 

Cheers

 

GJB

[CaptainPanic]

Captainpanic,

sur electric outboard that are on the market can run longer than that?

Oh, yes... you misunderstood me. I was just talking about the ratio of the time of pedaling to the time you can go full-power with the smallest motors... which is about 1:2. Below, you say it is more like 1:7.5 (because you picked a larger motor than me).

 

What I envision is this: A store bought electric motor moves the boat while the helmsman is pedalling away to charge the battery,( or if that's a bad idea he could charge the spare battery. For example I will take a 2hp Torqeedo, (2hp= 1500 Watt?), while the helmsman is pedalling 200W. Which is 7.5 times less.

So in fact the first thing I will achieve is some more sailing time. In Europe many people just take short trips. And if I keep pedalling while at anchor I will gain some more sailing time. And i like your idea of solar power, that could be added in the mix since the type of boater for this type of watersport will be your typical "nice weather sailor". I have to look for this solar cell foil that's supposed to be on the market, maybe it will produce another 200W when I cover the cabin roof with it.

 

Again thanks for your input I might be getting somewhere

 

Cheers

 

GJB

2hp is about 1500 W, yes.

 

Good luck!

[michel123456]

The Daedalus airplane has pedals. Maybe you can find more information about it.

 

And I forgot to say that I,m no speed freek pottering along at 2 or 3 mph on a small lake or for example the French Canal du Midi would be great for me.

 

Canal du Midi, wonderful !

 

-----------------------------

 

about pedal power. Note that the seat is up, like on a bicycle, and not down like in your link. Edited October 24, 2011 by michel123456

[GJB]

Michel123456,

yes that's right, you know I'm on the lower extreme watersport expierience thing.

 

No oceans for me with enormous waves, storms and what not.

Putter along, buy the local cheese, whine etc , catch some fish, take swim, explore that interesting restaurant... well I think you get my drift.

 

That's my favourite way of "sailing".

[michel123456]

Bring me cassoulet from Castelnaudary, and saucisses de Toulouse, with foie gras.

My best memories are from there, a long time ago...

And there a lot of instructive things to learn: about the way a lock work, the way the canal was build, the peculiar engraving on the stones, etc. Simply a dream.

 

Here below the canal over the river at Bezier, build circa 1680

Edited October 24, 2011 by michel123456