In 1980, AHS International inaugurated the Igor I. Sikorsky Human Powered Helicopter Competition. On Thursday, they announced a winner: Canada's Kickstarter-funded startup AeroVelo. The AeroVelo Atlas quadricopter, piloted – and, of course, powered – by company cofounder Todd Reichert, won the $250,000 prize by satisfying each …
An Inspiration to Dreamers Everywhere
Just goes to show what inspiration, perseverance and brains will get you.
The effort and engineering expended was stupendous.
Now figure out a way to scale that down s it can fit in a garage & run on solar & batteries and you will have the world at your feet.
Several pints to each & every participant!
Re: An Inspiration to Dreamers Everywhere
WRT the several pints. If I could find a pub with a large car park and judge the sea winds correctly could I use this as a legal mode of transport?
Leonardo, you WERE right on the money!
400 years after your groundbreaking designs, your dreams are vindicated. Man-powered flight is now a reality. The flying machine just needed to be... a tad bigger... than what you envisaged!
Re: Leonardo, you WERE right on the money!
...and significantly lighter than the materials of his day would allow.
Hard to believe it was possible
I have to give some credit to Kickstarter, though I still think it needs to incorporate some project management...
If it's 58 metres in width, then how does it fit into a 10m2 area? Is it managing to fold space and time, Tardis-like?
And as to Leonardo, chances are he'd be looking up from below: his craft never stood a chance of taking off. But still, he would no doubt be chuffed.
It doesn't fit. The goal is to hover without lateral translation so the effective center point is bounded by a box 10m on a side. I admit I'm not clear if it's indeed a box or a circle but meh.
The idea is that it doesn't use forward movement to translate into lift (like the gossamer albatross). Helicopters can increase lift if they are moving so a true test of human power is for it to be relatively stationary. It also demonstrates some degree of control.
I think it was a great achievement, made to look a bit too easy!
Somehow I dont think I will be able to use this to pop down the shops.
It's a huge quadcopter powered by one guy.
I did not know this prize even existed. What's even more amazing is that it was established decades after the kramer prize and shortly before the KP was won. TBH I'd thought thought the helicopter might be easier as the "wings" that give lift also give thrust and you can have as many as you like.
Keep in mind that engines to replace humans can be much smaller and lighter, leaving room for an actual payload. And yes Aeroresearch did do tests with the Gossamer Albatross to test this.
Not quite sure what use it is but thumbs up for another challenge met.
Size (and slowness) is everything
A simple bit of maths and physics shows why this thing has to be huge. Heavier than air flight (in open air - ground effect flight is different) is achieved by accelerating a mass of air downwards, and it's the counterbalancing force upwards which keeps the craft airborne. As the force is the mass of air times acceleration there is the choice of accelerating a small amount of air very fast or a large mass of air relatively slowly. If you accelerate half the mass of air per unit time as twice the rate to achieve the same thrust, you impart twice as much kinetic energy in total (as kinetic energy goes linearly with mass and to the square of velocity). It's all a bit more complicated, but that's the nub of it. That is roughly why high bypass jet engines are more efficient than low-pass ones, why jets are more fuel efficient than rockets for the same thrust and so on. In short, all those wondering why this sort of technology can't be scaled down to more manageable sizes in energy efficient aircraft (or flying cars) are wishing for the impossible. If you want fuel-efficient heavier-than-air flight, then you need to accelerate large masses or air gently - that means large and slow; large wings, large turbines and son on. None of your little rotors embedded in a flying car body. It simply won't scale (downwards).
Re: Size (and slowness) is everything
What about ground effect? Textbooks say that the ground effect is noticeable up to a height of "a tenth of the wingspan" or similar. So with big enough wings the ground effect still helps at 10 ft, where a smaller wing is already out of th eground effect.
Re: Size (and slowness) is everything
"What about ground effect? Textbooks say that the ground effect is noticeable up to a height of "a tenth of the wingspan" or similar. "
Ground effect is effective to rather more than a tenth of the span. It gives very noticeable drag reduction at 4-5m height to a 15m glider: I've flown an SZD Junior (35:1 glide ratio) in ground effect, starting at around 15ft altitude and 70 kts and, 750m later, was still at 15ft and still had 60kts on the clock, at which point I popped the airbrakes and landed, having flown most of the length of a grass runway into a light breeze.
Without ground effect and at its most efficient speed, 48kts, I'd expect a Junior to be on the ground in less than 175m from a start height of 15 ft. Above 60 kts its glide performance is rubbish, so evidently ground effect had a major effect.
Re: Size (and slowness) is everything
I like that explanation, I really do and I am not going to down vote you but.
Those are wings and not air screws; Bernoulli effect applies more than brute force inclined plane.
Curious to know...
How is the peddling energy being translated into to the props?
It's hard to see...
Is there a diagram somewhere?
I too was looking for the power train. I believe the traditional chain provides a high strength to weight ratio, but even in titanium would be relatively heavy for such long runs. Perhaps this solution is one of the team's major innovations. I was also wondering why the pilot was pedalling so slowly. A somewhat faster cadence would likely give a higher power output for most riders. Could this be a sign of a weak "chain"?
Me too, at 0.26 there's a shot that shows some sheaves right under the pedals so I thought it must very thin light drive belts and the round things below the rotors pulleys but then at 0.51 there's a shot that show lines to below the pedals with knowts that are not moving
I'm wondering why they kept the bike rear wheel and a drive to it unless it's a part of the transmission.
I wonder if the power is transmitted by winding in a single kevlar thread from each of the large pulleys (the conical structures under the rotor hubs). These could be pre-wound with just enough thread to last the required minute of flight. The four threads could be wound onto the drums which are to be seen near the pedals. This would be a very light and simple system but of course could not operate continuously.
ISTR toy helicopters where you wound a string round the rotor shaft; when you pulled the string the rotor would jump up into the air.
I'd guess that the rear wheel is there to act a bit like a flywheel.
If you've ever tried riding a cheap exercise bike (one that just has pedals and a turnscrew to provide resistance) you'll have found that it's nothing like riding a real bike because as soon as you stop pedalling, all momentum is lost.
With the rear wheel, even if the rider relaxes for a moment, the rotational energy of the rear wheel keeps things going.
Re: Power train?
that's what I came up with.... chains and belts would produce insane amounts of drag over the size of the structure, and indeed, they are winding in from the bobbins at each rotor, a really elegant and simple solution to a potentially airframe collapsing problem!
this video has impressed me to quite a degree! I just wish I could see the thing working in the flesh!
"I was also wondering why the pilot was pedalling so slowly."
I assumed that was for stability reasons. ie the mechanics are designed specifically so it's slow and powerful pedaling rather than fast and unstable. That whole contraption is made to be as light as possible so strength and bracing will at be the bare minimum.
I assumed that was for stability reasons. ie the mechanics are designed specifically so it's slow and powerful pedaling rather than fast and unstable.
Hmm, you'll notice the cadence of track specialists is much higher and there is definitely no bounce, as it's called. And any extra movement side to side, or any other direction, is wasted and can't be afforded. Remember, the feet are moving in a circular motion exactly the same as if you were using your hands. Perhaps you're thinking about the amateur who only pushes down on pedals and doesn't spend hours learning to pedal efficiently, thus only using a small portion of available power and wasting a lot as well. In any case, you may be right, and if you are then that is good news, because it would mean that future attempts could possibly have much more power available.
Re: Power train?
It does appear to have four pulleys on the crankshaft which are drawing in lightweight thread to drive the rotors. I wondered why they kept the extra weight of a wheel and chain with it's very high gear ratio. I suspect it provides both a flywheel and a bit of gyroscopic stability: not exactly sure why the use an apparently stock wheel rather than some kind of carbon-fibre disc with appropriate weight on the rim...
Amy! For the love of god keep pedaling!
Mines the one with the Futurama dvds in the pocket.
And now, for a tilt-rotor version
Parking might be a bit of a problem ...
Not really flight:
Staying in Ground Effect takes a LOT less power than flight out of GE does. Think of hovercraft.
...with their bloody fixie bikes.
That is crazy and beautiful. It looks like a slow undersea creature hovering in the currents. Not practical at all, but with only your muscles you can actually lift off the ground, not float, not glide, but move. I Love This Stuff.
We had chopper bikes way back in the 70s.
I love the look on the guy's face while he's in the air - in my neck of the woods, we call that a "shit-eating grin". Good stuff.
Great achievement. Now, in keeping with Canadian Tory tradition, PM Harper will move in, kill the project and destroy all the hardware. (Diefenbaker, Avro Arrow)