Help Design a Human-Powered Helicopter

[jzvonek]

Hello,

I have started a website to facilitate the design of a human-powered helicopter. Please visit this website if you are interested in joining:

http://sites.google.com/site/humanpoweredhelicopter/

We need great engineers to solve this difficult problem. If interested in giving your time, please email me at jzvonek@gmail.com.

Thanks.

-John

[russ_watters]

Difficult indeed! At face value it seems like an impossible problem!

[berkeman]

Looking at the human-powered plane efforts, and being an amateur bicyclist, I see no way for a human-powered helicopter to be practical for more than a few seconds. Ouch.

[Phrak]

First you need a good cyclist. Bringing the blades to velocity is an issue. I'd read the fine print over how to torque it up. The less stress on the pilot to overcome inertia under potentially adverse gearing could be a major issue.

Only 3 meters?? A lot of ground effect is in play. Can the rotor tips be closer to the ground than 3 meters?

Stability and control I would leave up to electronics if allowed.

The Gossamer Albatross had a wingspan of 47 feet with a root cord of about 6 feet. The top speed during the Channel crossing was 18 mph. Keep that in mind when you consider rotor diameter. Isn't it the last 1/4 of the rotor blade that does half the lifting?

So where are the rules of the game? A Wikipedia page isn't enough.

[jzvonek]

Here is a link to the rules:

http://www.vtol.org/awards/hphregs.html

Also, the prize has just been increased to $250,000 from the original $20,000.

I don't know if ground effect would be significant with the slow-moving rotors of a human-powered helicopter. I've seen experiment results that show the effect dropping off quickly as the rotors move away from the ground (< 3m).

Stability and control will be major issues, and I believe electronics are not allowed by the rules.

And the problem is not impossible. We have better engineering tools than at any time in the past. We just have to take advantage of them.

[mgb_phys]

When they say 'human powered' - do they count 'human fuelled'?
A gas turbine will run on bio-diesel !

[waht]

Looks like you are going to need Leonardo on this one.

[FredGarvin]

He's gonna need angels for this. They're the only way a human powered helicopter is going to get off the ground.

A gas turbine will run on bio-diesel !
It's people. Jet fuel is made out of people. They're making our jet fuel out of people.

[Phrak]

I wouldn't be as quick to dismiss a human powered helicopter. But, according to the set of rules quoted, it has to take off and remain within a 10 meter square. This limits the blades to about 4 meter each.

I'm not versed in helicopter efficiency, but it seems that twice the rotor disk area should about double the efficiency. Earlier I noted that the Gossamer Albatross had a wingspan 47 foot span. This might compare to a 47 foot rotor disk.

[FredGarvin]

I'll absolutely dismiss it. The power that can be provided by a good cyclist is somewhere in the area of 300 W. Not only will you be hard pressed to find a very light person that can put out that kind of continuous power, you have to deal with the structural aspects of aa helicopter. It does not lend itself to light and whispy structures like the Albatross did.

[Phrak]

... you have to deal with the structural aspects of aa helicopter. It does not lend itself to light and whispy structures like the Albatross did.

Why is that?

[FredGarvin]

Look at the rotor head and blades alone.

[D H]

I wouldn't be as quick to dismiss a human powered helicopter. But, according to the set of rules quoted, it has to take off and remain within a 10 meter square. This limits the blades to about 4 meter each.
You are misreading the rules. It's not the whole vehicle; just one single point on the vehicle.
A reference point on the non-rotating part of the machine will be established an a means whereby the observers can judge that the machine stayed within the confines of the 10-meter square.


I'll absolutely dismiss it.
The basic feat has already been achieved, twice. Just not for the requisite time and height.

[jzvonek]

D H is right. Human-powered helicopters have already gotten off the ground. A few great ideas on how to improve the design will win the prize.

[Phrak]

You are misreading the rules. It's not the whole vehicle; just one single point on the vehicle.
A reference point on the non-rotating part of the machine will be established an a means whereby the observers can judge that the machine stayed within the confines of the 10-meter square.

Yes, I believe you're right. It's ambigiously written.

[D H]

How is that ambiguous?

[Phrak]

How is that ambiguous?

You're joking? Nowhere is it stated what parts of the craft cannot drift outside the square, or even for that matter if they are talking about the 'reference point' staying in the square.

[Phrak]

Look at the rotor head and blades alone.

Well, it doesn't have to support a gun plateform, and there's more than one way to skin a cat. Look at the toy models available and their novel designs.

[Ranger Mike]

He's gonna need angels for this. They're the only way a human powered helicopter is going to get off the ground.


It's people. Jet fuel is made out of people. They're making our jet fuel out of people.

Fred...them old Charlton Heston movies are really takin their toll on you, aren't they??

[FredGarvin]

The basic feat has already been achieved, twice. Just not for the requisite time and height.Source please. A quick Google search showed a "helicopter" that barely got off the ground and which I agree is a human powered hovercraft, not a helicopter.

The competition states that they have never awarded this award.

I'll sit firm in my skepticism.

[sylas]

Current world record holder is apparently "Yuri I". In 1994, it achieved an altitude of 0.2 m and a time of 19.46 sec with a drift of 9.95 m. It has four separate rotors, all mounted below the frame. More details: Yuri I (http://www.humanpoweredhelicopters.org/yuri1/index.htm) at www.humanpoweredhelicopters.org

Thumb below is a clickable link to a full size image at the above website.

http://www.humanpoweredhelicopters.org/yuri1/YURI_1_thumb.jpg (http://www.humanpoweredhelicopters.org/yuri1/YURI_1.jpg)

[FredGarvin]

My definition of "helicopter" differs GREATLY from theirs.

.2 meters is well within ground effect. It still looks like useless form of a hovercraft. But I guess everything has to start out somewhere.

[FredGarvin]

Fred...them old Charlton Heston movies are really takin their toll on you, aren't they??Hey. MGB started it...

[Ranger Mike]

Hey. MGB started it...

i stand corrected..a lot of pathos out there ,Pathos (pronounced /ˈpeɪθɒs/; Greek: πάθος)

[russ_watters]

After looking at the rules, I believe the contest is doable. It only says you need to momentarily exceed 3 meters and total hover time is only 1 min. A cyclist can put out a lot more power for 1 min than s/he can for three hours.

Just keep in mind, this is nowhere close to the achievment of the Gossamer Albatross, which actually had sustained, controllable flight for close to 3 hours. This "helicpoter" prize seems pretty pointless to me.

[D H]

This "helicpoter" prize seems pretty pointless to me.
Depends on the meaning of "pointless". As a viable form of transportation for the masses, I agree. (Then again, so is the Gossamer Albatross.) As a college engineering project, I disagree. Something like this could be quite instructive.

[FredGarvin]

As a teaching tool I completely agree this is a good contest. However I still think that putting the moniker of helicopter to these machines is akin to me calling my 3 year old's tricycle a human powered car.

[Phrak]

From http://www.humanpoweredhelicopters.org/davinci/index.htm

This is a picture of the Da Vinci 3, rotor tip, I think.

Is that a spool of kit string I spy in the rectangular cut-out?

http://www.humanpoweredhelicopters.org/davinci/image003.jpg

Joe, the guy with the yellow nametag will be the pilot for today's demonstration.

[chayced]

What about cheating? Use a person to charge a spring then the spring to spin the rotors and lift the craft. Technically it's human powered, and it gives you enough power to actually lift off.

Beyond that I don't think it's possible, unless you are using huge rotors and then it's more of a spiraling airplane than a helicopter.

[Phrak]

As a teaching tool I completely agree this is a good contest. However I still think that putting the moniker of helicopter to these machines is akin to me calling my 3 year old's tricycle a human powered car.

Pointless? But think of all the money and glad-handing. The professors get to publish on every meaningless detail, foundations get to disperse funds and claim to be important contributors, post grads get to slick-up their resumes, fundraisers get paid. It's bounty all around. They just have to get the silly contraption suitably aloft...

[dr dodge]

in the rules it says no energy saving devices, but the rotor assy is exempt. use the rotors(2+ counter-rotating) as flywheels. it states a flight lenght, but I didn't see a total time duration. If it took 2 persons 2-5+ hours to slowly keep spinning up the rotors (w/ no lift) until lift off, I would think, in theory, the energy stored could excede the extra energy to then hang it in the air long enough
how long to the tour biker's ride continuously?

dr

[dr dodge]

if the target web site has a way to contribute ideas I could not find it
so I am going to toss this out in here
if 3 rotors were used, each of different mass, smallest (in diameter) was heaviest, largest lightest, and a variable gearbox could divert torque between all 3, you could generate rotor speed with all of them, then feather the power to the largest diameter one to speed it up, and use the middle sized one for counter rotational stability. since reaction of pedaling would want to spin you around, you could offset that by having the middle rotor of equal "inertial mass" as the body, and compensating for no tail rotor. all lifting surfaces would not cover the next. from above it would look like 3 concentric circles

dr

[liannagreyson]

Very nice post with a ton of informative information. I really appreciate the fact that you approach these topics from a stand point of knowledge and information
instead of the typical “I think” mentality that you see so much on the internet these days.

[dr dodge]

I just checked the web site the OP was starting, and seems as though it is not being updated. so, I'm in if someone wants to take the lead and we build one. Since I have my own industrial park in the back yard, we should be able to do it on a shoe string.

dr

[M Grandin]

If "Gossamer" manpowered planes work, at least I cannot see anything preventing two such planes connected together circulating around a common center = "helicopter". That may be boiled down to a man powered helicopter where the rotor is not driven by center shaft, but from from smaller propellers at rotor wing ends. Wing units (perhaps several parallel layers as in WWI combat planes) behind towing propellers, placed rather far out from center
shaft. Propellers could be driven by wires as in garden trimmers.

I agree it may appear less efficient letting rotor be towed by propeller - but I can see
gossamer planes (towed by propeller) lift while manpowered helicopters (driven by center shafts)
don't lift. In aerodynamics not always common sense applies. :cool: