Human Powered Boat

In addition to stated above I wanted to say the Hobie MirageDrive has considerable disadvantage: it cannot move kayak in the counter direction. The sine wave propulsion device can do it.

 

Wow, that's great, maybe you should start a thread on that.

 

It is a good idea. I will.

 

I just arrived at your thread. Thought you might want to know about my experience with a human-powered craft I just assembled and peddled-paddled down the connecticut river. The propulsion was a peddle driven prop made by a farmer in nebraska (pedalpro.com) and a colorado river raft made by Jacks Welding, in New Mexico. Add a bimini top and the rigs complete. I use a 10ft paddle which I stroke while peddling (I've secured the motor and use the paddle for directional control in addition to force). This way my hands are free when I want to stop paddling.
I average about 4 mph at a very leisure pace. Boat and motor and camping gear weigh in at about 150 lbs. I have photos if anyone's interested.

 

hobbie mirage

check out hobbie mirage drive, sea mamals dont have props!

 

check out hoibbie mirage drive

 

Drive is set

There will be no changes to the decided upon drive line. The experiments, mock-ups, training schedule, hull friction numbers and more have alll ben worked out so no ammount of nontraditional propulsion advertizing and testimonial will change that.
It, as stated several times, is a pedal crank connected via 6:1 sprocket and chain reduction to the 1:1 bevel gear (way less friction than some have offered) straight out the 5/8" monel shaft to the carbon fiber prop.
Basicaly a recombant seat finishes it off.
SG

 

This is one of the most lengthy threads I have seen. Plenty of interest it would seem. Solomon you write like an above average, intelligent person, but you surely must be a bit of a nut case. OK. I truly admire pioneers and I wish you well in your madcap adventure. I can think of quite a few nut case pioneers who went down in history, guys like Magellon, Armstrong, and a lot more. Almost everyone said the Wright brothers were crazy too.

Have you and your designer given adequate thought to windage ? No doubt you have seen pictures and descriptions of the long distance human powered boat by Bolger. Its' description is in one of his books; Boats With An Open Mind. Bolger has given emphasis to aero drag features along with safety considerations. 2300 Nm is a long way to pedal and any possible reduction in effort is of paramount importance.

If you make good 30 Nm one day and are blown back 60Nm by the next days' storm, it'll be disappointing to say the least. Better to be streamlined and blown back only 40Nm.

I join Cyclops in being concerned for your safety. And I join the rest of the subscribers in hoping fervently that you will be successful.

 

I really want to know about your experience with a human-powered craft. Could you send your information and photos in my address please?
vladimirz@iimetro.com.au

 

nut jobs

messabout,

Yes, windage is necessarily an issue here, yes I have seen and studied bolger's boat (I have a copy of his book) our boat is designed with low windage in mind as at the speeds we are talking about and the distances to be traveled, it will be more of a point and go boat. She can manuver just fine but she is designed to take advantage of favorable currents and to hold her own unfavorable conditions.
Yes, it seems the jury is in, I am a nutcase.
Nevertheless....
Nobody has said that to my face since I got out of Hell Week in Seal training.

 

...and

Oh, btw...thanks for everyones concern and support, it goes along way here. Even some of our board of directors have a difficult time envisioning our eventual success and there is a chance the effort will fail. There is a good reason nobody has ever completed a human powered solo circumnavigation...it is hard. But nothing will deter us from making the attempt anyway. There will allways be some ignorant person who refuses to believe the world isn't flat or this or that is impossible. That's fine. Small minds have no bearing on our effort.

 

human power

Hello: I found this thread quite interesting. As the current holder of the 24 hour human powered vehicle distance record (650 miles), I think I can offer some advice.

When you are estimating your daily average distance based on your average expected wattage output, please make sure you properly consider non-pedaling zero's bringing down your average.

you said:
-------------------------------------
According to the math, at 100% efficiency, the boat requires .096 hp to make 3 kts. Our experiments have shown that I can comfortably sustain 1/5 hp over an extended duration (several hours) with bursts to 1/4 hp and topping out at 1/3 hp. So at 50% efficiency we should still be able to make 3 kts. for extended periods at full load.
--------------------------------------

1/5 HP is about 150 watts. To end up with an AVERAGE of 150 watts at the end of the day, you will probably require 180 watts while cycling.

My ending average wattage on my world record 24 hour attempt was only 115 watts. This includes 8, short pit stops and brief periods of coasting. The previous record holder's average watts were 110. I have a study (can't find the link to it right now) of a top RAAM (Race Across America) rider, and his ending overall average wattage was only 98 watts.

typically, most people (and I have been guilty of this myself) over estimate their ending wattage average because they fail to consider how much effect the down-time has on the average.

Is there a calculator available that will estimate power required to push a HPB through the water given it's hull length, weight and displacement???? I am very interested in designing an expedition class HPB, and would like to 'play' with some various ideas.

Thanks!
Greg K

 

power calcs

Greg,
That's awesome. Congrats. I understand my average output will be less over time but I don't have to average any particular output number, only keep the boat going 1.5 kts or better for the times I'm pedaling. There are formulas to calculate the power required to push any displacement hull through the water and they are based on the craft's resistance #'s (frictional and wave making) our modeler uses a computer program for this but I think it is something like .00307 x (Rw+Rf) x (V) velocity in nm/h
Good luck to us both.
SG

 

Greg- Congrats, for starters, and welcome aboard boatdesign.net!
As for your HPB idea. If you're reasonably OK with computers, a pretty easy and surprisingly accurate way to get drag and power data for displacement hulls is to combine Michlet and Freeship. Once you're familiar with these programs (a matter of a few days of playing around) you can make a change to your shape, size, displacement, whatever in Freeship, then run that in Michlet to get the drag and power estimate, then put those results in Excel to compare against your previous version- in only a few minutes. http://www.freeship.org and http://www.cyberiad.net/michlet.htm are the links to these (both free) programs. HPVs tend to be long, slim and slow, perfect conditions for Michlet to give pretty good data.
SG- I've been following this thread since it started.... looking forward to seeing you on the front page of the Star in the not-too-distant future Good luck!

 

Hpv

Matt,
Thanks,all along this effort your input has been helpfull and appreciated. If I don't make the front page of the National Enquirer then I'll be in the obits in the PT Leader.
www.ptleader.com

SG