I was following this for a little while...
and I found myself a little disappointed considering their initial goals of hovering over 3 meters for 60 seconds.
A Japanese team already did really well in 1994 with human powered helicopters, with an almost identical design. www.youtube.com/watch?v=CNMTryyvY1Q. I was hoping for a bit more considering the advances in technology since then.
The thing I found puzzling was how fast the pilot had to peddle. It seems far too fast, and didn't look too efficient. I would have suggested a higher gear ratio and slower, stronger peddling. I also think that riding position looks very uncomfortable, but maybe that's just me. I'd prefer to peddle 'bike-style' rather than sitting down...
*Aeronautics rant over*
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guffguff fuckes your gradeds balls!, Fri 13 May 2011, 16:44,
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Well its just a first step
That's still the goal. However its notable for being the first recorded flight.
The peddling didn't look very efficient to me either. I'd guess they're going to have to alter that for the full attempt. As for the seating position - I guess that's a function of having to save as much weight as possible. Recumbent bikes use a similar seating position though so it can't be that bad.
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evil_andy Stick stick stick stick sticky sticky stick stick, Fri 13 May 2011, 17:01,
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I'd have thought a bike position would be better for weight savings
because you don't need a seat. You could support your weight on the peddles on the down stroke. That said, I'm sure they've done their research into this.
I agree with it being a first step though. I guess they still have tests and alterations to make, but I would have liked to have seen something more. I hope they manage to win the prize, that'd be cool.
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guffguff fuckes your gradeds balls!, Fri 13 May 2011, 17:12,
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Nope - I'm a cyclist and this is why the prone position is better:
By relieving the need to support the upper body, you can fully engage the gluteal muscle set to deliver greater and more consistent power than the standard upright bicycle position (that said, the greatest advantage the recumbent rider has against the standard bicycle is aerodynamic).
For the homocopter, the decision was almost certainly made as much for keeping the centre of balance as low as possible as it was for power transfer. The 'copter looked like it had a very low centre of gravity and was very light, so having someone pedalling away (with their upper body swaying left and right, unsupported) would have probably de-stabilised it too much.
(, Fri 13 May 2011, 17:22, Reply)
I was going to say something similar but not quite as succinctly and splendidly as ^^^ this ^^^
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emergency_pants Today I smell of... tea tree, Fri 13 May 2011, 18:18,
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But if you rotated her about her hip...
so that she was facing down, then her centre of gravity would be lower. I'm not going to argue with a seasoned cyclist, but surely if you supported her upper body with a harness or some such device, then it would leave her legs free to move over a much bigger angle range, and make more effective use if them. By sitting down, her legs can't bend back greater than the angle of the seat to the upright which it's fixed to, limiting the performance. I'm just thinking from a purely engineering standpoint.
Also, such a big machine with low mass and relatively high stiffness should not be destabilised by the oscillation of a human peddling at the frequency that she was in the video I wouldn't think.
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guffguff fuckes your gradeds balls!, Fri 13 May 2011, 20:00,
Reply)
The official term for that is 'Prone Recumbent' (lying on your front)
And it's much less popular for the simple reason of being very difficult to find a comfortable position, with the added bonuses of:
1) Compacting the front of the torso when you need to breathe very heavily
2) With the knees having to extend downward instead of upward every stroke, the entire body needs to be placed higher to compensate, so you are in fact forced to raise the centre of gravity (or worse, in a bike, give yourself a higher aero profile, reducing or even negating the chief benefit of a 'bent).
3) You force the body to work harder in the rest phase of the stroke - to illustrate this, sit down on the edge of a raised surface (bed, sofa will do fine). Lie on your back, stick your legs out straight, and hold them there for a few seconds. Now roll over and do the same on your front. You'll see the muscle and bone structure make it naturally much easier to do on your back than on your front.
(, Fri 13 May 2011, 22:23, Reply)
Well...
I can imagine another problem with the bike position being that you bob your weight up and down when you're cycling like that. The whole aparatus would move up and down while it was flying, which wouldn't be conducive to breaking some "time off the ground" record.
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RadioElectric, Fri 13 May 2011, 19:33,
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