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Human Powered Helicopter Aims To Break Records
An anonymous reader writes "A team of 50 from the University of Maryland has developed a human-powered helicopter, 'The Gamera,' which took two years to complete. The size of the helicopter is one third of a football field. The helicopter is made from light materials such as balsa, mylar, carbon fiber and foam and weighs about 210 pounds. The team aims to have it hover at least 3 meters off the ground."
The article summary is quite misleading given that the 210-pound figure includes the weight of the pilot.
Someone figured out an appropriate use for the football field.
So... a carnie wearing stilts will look down at you and laugh?
DaVinci would be jealous.
www.awkwardengineer.com
I'm sure they wouldn't allow a helicopter that uses air earlier compressed by the human pilot so what about stored momentum in the blades and machinery? Also do air currents count as stored energy? Obviously this couldn't fly without the ground effect... Just some thoughts.
If video games influenced behavior the Pac Man generation would be eating pills and running away from their problems.
....without a ramp. (HPV = human powered vehicle).
I agree. There's no way that this experience/technology could ever be applied to anything useful.
/sarcasm
So is it fueled by Soylent Green?
Consider it public-sector funded basic materials research that greedy fucks can then exploit. Maybe now you'll approve.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Da Vinci would be proud.
Why was this posted in IDLE?
"Human Powered Helicopter Aims To Break Records" ...and bones!
This looks like a near-clone of the Yuri I (the last successful human-powered helicopter), but slightly bigger and heavier:
http://www.youtube.com/watch?v=caHCbuh_Yyc
My quick back-of-the-envelope calculations say that it won't get more than 1 meter off the ground for any significant length of time. If it was much bigger (2 or 3 times) it might have a chance, but at this small size it will be depending too much on ground effect for extra lift, just like the Yuri I did. Fly too high - over 1 meter or so, if the Yuri I is our guide - and that effect disappears.
They also haven't added any twist or taper to the rotors, so they're not getting any extra efficiency gains there, either.
Not nearly enough real action with only the tiny snippets... Bleh
For justice, we must go to Don Corleone
The test flight is supposed to happen tomorrow. Why not wait till there are results before posting an article?
What kind of football?
Have gnu, will travel.
...compared to just climbing up a ladder?
What I mean is the human body has easily enough power to raise itself up a vertical ladder or rock face so presumably a huge amount of this power must be lost just moving air around when that power is used inside a human powered helicopter. But how much power is wasted , or to put it another way , how much power put into the system is actually used to raise the mass of the helicopter?
They're chasing after corporate money from Sikorsky you dumb fuck. Way to miss the point.
Yeah, but once you're on the ladder, you're on the ladder. (Unless you manage to fall off).
Energy wise this would be like continually jumping up and down.
Not to diminish their considerable task, but their rotor sizes means they are required to hover within ground effect, which considerably reduces the overall challenge. Again, that's not the same thing from saying their challenge is easy - as it most definitely is not.
...compared to just climbing up a ladder?
What I mean is the human body has easily enough power to raise itself up a vertical ladder or rock face so presumably a huge amount of this power must be lost just moving air around when that power is used inside a human powered helicopter. But how much power is wasted , or to put it another way , how much power put into the system is actually used to raise the mass of the helicopter?
You're mixing mass, power, and impulse all together. impulse = F * delta t = m * delta v
So the force is pushing down with the combined weight of the vehicle for a certain time in order to hover in place, which is equivalent to accelerating a mass (lets say, the vehicle) to a certain velocity. So hovering for 10 minutes takes the same impulse as accelerating (lets say, horizontally) to some absolutely ridiculous velocity. I forget the crossover but, hovering a copter for X minutes is equivalent to pushing a car 0 to 60.
The power level is in the low single digit horsepower for a good athlete for a minute or two. Good luck dissipating even one horsepower for a "long time".
Also note that people climb extremely slowly. Over a long term, best expressed as seconds per foot rather than ft/sec. Classic high school physics problem is having the strongest track athlete try to climb a flight of stairs as quickly as possible, with the horsepower result usually being pretty depressing.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Pride is certainly one of them, and they spell it out in the promo. I have to hand it to the PR group at the UM that seem to have done a better job of actually finishing their project than the HPH have done to date. Setting up testing apps, fixtures are all great, but really what is the world is this going to do for practical aviation based on technology that is 100s of years old now? What is the economic and ecological footprint of this project? To achieve a goal, sure it is notable. But is it really worth it in the careers and advancement of education? I ask, wouldn't the money, time be better spent on more practical and useful applications? I say yes.
I have an idea! How about they take a small 2 stroke engine and add it to the thing. Also a closed cockpit would be nice. Make the vehicle a bit more compact, maybe 1/4 of the size and then we can start having a conversation about something that's useful.
You can't handle the truth.
...compared to just climbing up a ladder?
What I mean is the human body has easily enough power to raise itself up a vertical ladder or rock face so presumably a huge amount of this power must be lost just moving air around when that power is used inside a human powered helicopter. But how much power is wasted , or to put it another way , how much power put into the system is actually used to raise the mass of the helicopter?
I'm not exactly sure what you're asking here, but think about it this way. Gravity is accelerating you downwards. When you stand on a ladder, the ladder's structure is resisting your weight, which is why you stay up. With a helicopter or airplane, you don't have a structure to hold you up, so instead you accelerate air downwards using wings. You push the wings through the air, they accelerate air downwards, you get supported.
So the easiest answer to your question is *all* the power put into the system actually raises the mass of the helicopter. A slightly more nuanced answer would be that the mass of the whole system (pilot + helicopter) minus the pilot's weight, is how much energy it takes to raise the mass of the helicopter, but that's sort of silly.
A side-note: there's something called ground effect that changes how helicopters (and airplanes and anything else relying on accelerating air downwards to maintain flight) work. When a wing is within about one wingspan of the ground, the air it forces downwards is somewhat constrained between the ground and the wing, giving the wing more lift than it would in free air. As a result, if you're within a wingspan of the ground it requires significantly less power to stay in the air. (If you watch airplanes land you'll see this effect as a change in their angle of approach just before they land.) The Sikorsky Challenge requires the helicopter to hover at a height that is within ground effect for most practical designs, so the idea of making a practical human-powered helicopter is even harder than making something that fulfills the Sikorsky Challenge.
Nostalgia's not what it used to be.
Many of these projects aren't so much about the end goal as they are about the learning process along the way.
If they can do it with a human, they could probably make it work with a solar powered engine of some sort......
The materials and craft design can lead to other uses....
etc.
reading the article only - ignorinig the video, I can only think: what record to break?
The record of measuring size in football fields? Please, give me something my non-American brain can relate to.
The record of measuring height using the metric system and weight using imperial? Done with little succes by NASA I believe.
After viewing the video, I know what record they'll break: The record of winning a prize...
schmellz like PR bs.
I think a major part of a successful outcome is to ask a world class athlete to fly the thing.
...the old joke of:
"I just flew in from Cleveland, and boy are my arms tired!"
Yes because 250k is going to completely pay for 3 years of aviation and materials science work. Less than the cost of a single small assembly line built aircraft. We should have thought of this earlier. I am sure companies would be willing to put up a cool 2 million for passenger jets. We've been doing it wrong.
----- 70% of all statistics are completely made up.
As in, Big Giant Turtle That Flies? You know, friend to children, Japanese movie monster, serious under-bite, shoots flames from mouth, extremity holes, etc.
:-)
I can't help wondering if multiple blades fastened to some sort of really thin but strong ring would be better? Like three blades would be a lot more stable? But what do I know?
PS Someone should take the footage, speed it up, make it black and white and play player piano music in the background....
They spend that much time and money for something that is not practical at the very least. Upon graduation they can take their new found knowledge and ask if it's for here or to go.
You could have someone pedal the thing for a couple of hours to store energy before attempting the flight.
I don't think it's easy, but it might open up some interesting possibilities.
Soylent Green Tartare perhaps
Ultimately any human powered helicopter would have to have some type of gliding mechanism to be practical. People can put out sustained effort for only so long. But if you make it more like a bicycle where you can coast and rest between bursts of intense activity, then you may really have something. We need to be aiming for a "bicycle of the air" with this, not mimicking what machines typically do for us.
Oh, and fail-safe too. If you get exhausted at 1000 feet up, it needs to gently drift to ground.
Even if they get all the rest right, I didn't see any directional controls on Gammera, so staying in the 10 meter box might be the biggest challenge, especially if they are depending on weight shifting of the pilot for control while she is peddling like mad with both hand and feet!
Also note that people climb extremely slowly. Over a long term, best expressed as seconds per foot rather than ft/sec.
I think you mean best expressed as inches per second or even better, cm/s. If you were moving seconds per foot then you'd be in some kind of Braid style dreamworld where motion in a given direction affected the flow of time.
Nick
"Fuck you I'm not peddling anymore!" :)
The Sikorsky challenge does permit using electricity so that instead of complex mechanical solutions, the human being could be pedaling to turn a generator and that power then used to turn an electrical motor. I'm rather sure that batteries are not permitted but perhaps such a solution would enable some more variation in the effort put in by the human being without it immediately disrupting the rotation since there wouldn't be a direct mechanical link. However, considering the short duration of the flight, I don't think a trained athlete has any difficulty in providing maximum power for such a short period of time. Or do you mean that you seriously think that a human-powered helicopter which could be used in any way for transportation could be designed?
I'm sure a copter with enough aerodynamic efficiency to support human-powered flight will be a joy to autorotate. Autorotation is the standard helicopter failsafe: if your engines fail and you're high enough and have some forward speed, you disengage the rotor clutch and let it spin freely, "gently" getting you to to ground. In a normal helicopter a proper autorotation IIRC is only designed to be survivable, in this human-powered one it should be not only survivable but very gentle, too.
A successful API design takes a mixture of software design and pedagogy.
Hey, you're back. We missed you and your mental rantings.
And the summary forgot to include that the test flight is today ?
Supposedly... don't have silverlight.
Press release
I think you mean best expressed as inches per second or even better, cm/s. If you were moving seconds per foot then you'd be in some kind of Braid style dreamworld where motion in a given direction affected the flow of time.
Seconds per foot is just the reciprocal of feet per second. Useful when the numbers are much less than 1. Think of ancient bipolar transistor alpha vs beta, once alphas got too high making all transistors 0.99-something the industry pretty much switched to reporting betas. For example an old person might climb at 0.14286 feet per second but its easier to say 7 seconds per foot.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Or how about approximately 4.4cm/s?
It's confusion around units of the kind you're encouraging that caused the loss of Mars Climate Orbiter! :)
Nick
It was a fail sadly they are trying again today looks very cool! http://www.suasnews.com/2011/05/5475/human-powered-helicopter-has-part-failure/