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Man Supposedly Flies With Custom-Built Bird Wings

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Re: Man Supposedly Flies With Custom-Built Bird Wings

#141

Post by pitchups »

baddox wrote: post #99
Jach wrote: post #59

Earlier quoted context omitted.

You can edit video titles...

... or wait and upload them all in a batch.

They were not uploaded in a batch - the first of the 14 videos was uploaded on Aug 5, 2011 [1]

So either a) he planned to make only 14 videos in advance - culminating in the flight video OR b) he went back and edited all of the titles.

So I checked the cached version of the previous videos - and it does appear that it is (b) - he edited all the titles adding the 14 after the fact.

[1] [http://www.youtube.com/watch?v=cocLpRzZnvk&feature=chann...]

Re: Man Supposedly Flies With Custom-Built Bird Wings

#142

Post by Lazare »

angersock wrote: post #114
Lazare wrote: post #110

Watch a bird take off. Start with some pigeons, then some sea gulls. If you can, watch an albatross - on YouTube if nothing else. As you get larger, you get heavier; as you get heavier you need more lifting force (ie, bigger wings, moving faster). Recall that weight is a function of volume and increases with the cube of your dimensions, while lifting force is a function of surface area and only increases with the squ…

For the record, he's budgeting around 17 m^2 surface area for wing and 100 kg for pilot ( http://www.humanbirdwings.net/about/working-on-the-wings/ ). That's about 5 kg/m^2 wing loading, well within range of something for a microlight( http://www.caa.co.uk/default.aspx?catid=1416&pagetype=90... ) if a bit heavy for an unpowered glider. EDIT: The wing surface (that kite he mentions sacrificing) is from one of these (…

It's not the power output of the motors I was questioning, but the overall strength of the system. A back of the envelope calculation (from a commentator at Wired) suggests we're seeing a lever ratio of around 30:1; simplifying greatly that implies each side is moving a 1.5 ton weight back and forth multiple times per second. This is challenging for far more than the motor.

Mind you, 2000w does sound low. The Festo SmartBird weighs less than 500g, and uses around 25w to fly. If you scale it up linearly, that says 2000w would be enough for 40kg, which is less than half what we need. But the Festo SmartBird is a vastly more sophisticated design, and among other things actually flaps its wings in a way which generates lift, unlike this guys design. (Very useful, that.) It's going to be much more efficient than this wing design, so we're actually looking at a much larger power deficit.

Incidentally, the Festo SmartBird is a pretty amazing project; anyone who found this wing design interesting would probably be interested in it. Check out this writeup with a brief video of the bird in flight[1] or this much longer video of the design process[2].

The second link, in particular, underscores just how impossible the idea of some guy on his own throwing together some wings and managing to fly is. Bird flight is an amazingly hard problem to solve, even for a bird sized model.

[1]: http://www.robaid.com/bionics/festo-smartbird-mechanical-bir...

[2]: http://www.youtube.com/watch?v=kA7PNQiHT1Q

Re: Man Supposedly Flies With Custom-Built Bird Wings

#143

Post by Lazare »

joeld42 wrote: post #136

I've worked in the visual effects industry and I don't think this is CGI, at least not in the sense that most commenters mean, a digital rendering of the dude and the wings. If it is, there's a lot of small details that they got right. It could be, and the poor quality of the video makes it hard to tell for sure, but I think that's misdirection. My guess is that the wings are not mechanical at all beyond being flexib…

Agreed. The editing and camera angles make it seem fake, but it doesn't look rendered. And, honestly...I think it's too bad to be rendered. The motion is just too artificial.

My money is on this being done with wires and some basic rotoscoping, not CGI. Everything fits.

Re: Man Supposedly Flies With Custom-Built Bird Wings

#144

Post by simeonf »

I'm just a beginning hang glider pilot - but everybody at the largest national hang gliding site (http://hanggliding.org) calls fake. The main clue from a hang glider's perspective is that the wings absolutely don't look loaded. Assuming power source, batteries, etc all were available there's no way those flapping trailing edges are actually bearing weight by pushing against the air.

Yes the dream of human flight is alive - but it looks like this - http://vimeo.com/20775072

Re: Man Supposedly Flies With Custom-Built Bird Wings

#146

Post by andrewfelix »

joeld42 wrote: post #136

I've worked in the visual effects industry and I don't think this is CGI, at least not in the sense that most commenters mean, a digital rendering of the dude and the wings. If it is, there's a lot of small details that they got right. It could be, and the poor quality of the video makes it hard to tell for sure, but I think that's misdirection. My guess is that the wings are not mechanical at all beyond being flexib…

Here's a much rougher version (skip to 1.45) http://www.youtube.com/watch?v=Q0tKFOcHyrI&feature=relmf...

Notice the camera pans down as it transitions to what is clearly an animation.

Re: Man Supposedly Flies With Custom-Built Bird Wings

#147

Post by marshray »

e03179 wrote: post #10
jsprinkles wrote: post #7

I'm skeptical. Am I the only one that noticed what appeared to be the plethora of CGI in the video?

I just can't figure out why they had the guy in the middle run straight toward the camera as he begins his "taxi".

Have you ever tried to video kids trying to launch a kite or a glider?

They really do act just like that. The camera person stops to video and everybody runs in front of him. The camera person needs to change position quickly so you tape the grass whirling for a few seconds.

Re: Man Supposedly Flies With Custom-Built Bird Wings

#149

Post by marshray »

ilaksh wrote: post #87
khalidmbajwa wrote: post #55

Interesting that Jamie Hyneman of the MythBusters fame Doesn't think it was faked. According him to the science checks out ! http://www.tested.com/articles/43440-thoughts-on-the-mechani...

OK but where are the batteries that Jamie mentions? I didn't see any in the video or the videos that came before it in the series about how they made it.

In earlier videos a guy even walks in with a cardboard box full of batteries. I think they're zip-tied low on the backboard.

Re: Man Supposedly Flies With Custom-Built Bird Wings

#150

Post by andrewfelix »

angersock wrote: post #88
avree wrote: post #19

Incredibly skeptical. Red flags: 1. He's received criticism about his videos before, but still insists on filming in random parks, only releasing to press after the event, and using blurry/shaky footage. 2. When he takes off, the camera shakes heavily. When he lands, someone steps in front to block the view. 3. At 0:35, his legs lift up so that his body is parallel to the ground (necessary for flight.) If he had been…

Why don't you read his dev blog? http://www.humanbirdwings.net/project-timeline/ It would seem that arguments about the system instead of the filming might, you know, be more productive.

That project timeline raises even more red flags. Prelim sketches to build in little over a month?
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