Pedal Powered Boats

Yes, somewhere on this thread there is a reciprocating drive powering a prop using a stainless steel cable which wraps around the drive shaft. Might do a search when I have time.

Porta

 

sher would be fun to see this unit or all other ideals.

i think about chain and spring load action for a push style.

joco

 

Look at the movies here for some ideas on cable drive:

http://forwardface.com/

 

thanks for the link.

but this cant be what i am looking for.

i want to use my foot..noy my hands i want my hands free off anything...mabe a little control rudder but no more.

i want to jst push kind off like a hobi style..but turn a prop in the back inted off flip flop fins under.

joco.....but thanks again.

 

Your welcome. These pages might help someone who is trying to build a press down type ie. use a spring to return the push pedals instead of pulling back with your hands on a cable. The hardest part in making such a unit would be converting a back and forth foot pushing motion into rotary for a prop. This shows the only way I have ever seen to do that.

I don't think there are any kind of push propel manufactured units that can be purchased that give good propulsion. Here is one that only has enough speed for manuvering only:
http://www.prophish.com/quickfin.html

Porta

 

The link Porta gave shows a system that WILL work with just two pedals pushing. The key to the way this works is one-way clutches that allow the movement of cables around pulleys to be converted into rotary motion that only goes in one direction.

The Z Rower in that link uses arm and back power to pull one cable and foot power to pull the other cable, but there is no reason why the cables couldn't just be hooked up to reciprocating pedals, one on each.

Somewhere in this thread, as Porta has said, are some photos of just such a system. It looked neat and efficient to me, but I'm not sure how much real-world testing it's had.

Jeremy

 

HI Guys,
I hesitate to stick my oar in late in this discussion but what about sail boat pedal auxiliaries? silly at first, but for the smaller boats, configured right it may be valid. Fuel is not always available, legs are. Speaking of which it would sure beat rowing or paddling, plus the addition of a generator option would provide a modicum of power. Also if windmill blades can generate force for electricity why not direct crank/prop power. Probably too much mechanical loss but... screwing myself upwind is an amusing thought. Green and outside the box.
Thanx, Jon

 

With a bit of ingenuity I think that a twisted chain prop drive, with a narrow chord two bladed prop, 'might' be made to fit down a centreboard case. If it could be made to fit, then this would give a nice pedal power auxiliary system for a small sailing boat with a centre board.

I've looked closely at generating power from the prop whilst sailing. There's certainly enough potential power to make it viable, hence the success of towed, in-water, generator systems. The problem with using the propulsion prop is that it needs to be optimised for either propulsion or generation; if optimised for propulsion it makes for a poor generator. Other than that, the electrical charging stuff is pretty straightforward to make.

 

Good info Jeremy. Steve Roberts of microship had a twisted chain setup many years ago (in addition to other supplementary power sources), it is probably in HIS archives somewhere. http://microship.com/

What do you think of using a push-pull gearbox (like you see on cordless drills) and perhaps a variable pitch prop to do both generating and propulsion? Another possibility would be a quick change prop ( within seconds) system. Maybe could be set up with a long, flex shaft drive system....

Porta

 

It might work. I was looking at using the same transmission and motor for propulsion and generation but concluded that I needed a bigger diameter, finer pitch prop for generation than I did for propulsion. The efficiency difference was quite marked, something like an 80% efficient propulsion prop would only be about 50% efficient for generation at sailing speeds.

The electronics turns out to be really simple with a brushless motor, as the cheap controllers I'm using have programmable regenerative braking. If you turn that on they turn the motor into a boost mode switching regulator/alternator, so you get a high enough voltage out, even at low rpm, to re-charge batteries.

 

Sure, you can't make a silk purse out of a sow's ear ......

I just came back from the Texas Water Safari, the 260 mile down river race starting in San Marcos and ending in Seadrift in under 100 hours. I plan to do this race next year so I went there to study, research and learn everything I could.
The winner this year finished in 34.5 hours I think. The top boats went without any sleep, no naps, no breaks. The first place novice class (first time beginners) in aluminum canoes did it in about 55 hours!
Sure, it takes training, lots of it, and serious nutritional needs and techniques but these guys and gals found a way to turn that "switch" on in a serious way. I'll let you all know how it goes next year, I'll be doing it solo .....

I'd also like to consider just how I can get a peddle drive system to work in this race, but I figure I got time to think about that while I do this race next year!. I'm still trying to decide what type of boat to use, if I have to I'll use my sea kayak that I did the 400 miles of the texas coast with but I can see a new boat design in the swirling gasses of creation ...... but it won't be a peddle boat, purely a single/double blade boat. I got much to think about before a peddle boat design comes anywhere close to the building stage.

 

There was some water around due to rains this year, making it fairly easy. Times go up considerably during dry periods because of portage time and thin water. I would go light weight as possible myself with good stability for the bumpy Seadrift finish. Did you see any inflatable kayaks? Maybe the Hobie could be modified to pack on supplies? http://www.hobiecat.com/kayaking/models_i9s.html

Porta

 

I'd not think the hobie could finish this course, rebar and log jams would kill it, or with it's width, it would kill your/my speed. No off the shelf boat for this entire course will work, it would have to be a custom boat. I'd think something based on Rick's v14 might somehow work, if it could somehow turn well. We lost a few boats this year, broke in half ......

 

If there are no restrictions on drug use, then that wouldn't be too hard.

Leo.

 

I don't think there is any drug testing but ......
you have to carry everything you'll think you'll need except
for water and ice that is supplied to you by your TC (team captain).
here's the website:
http://www.texaswatersafari.org/
and here's the forum:
http://paddle24seven.com/

pics I took:
http://www.sandslave.com/tws2010/

taking off from a checkpoint
and getting ice and water from the tc
July in Texas is Hot, Hot, Hot!