China: Man builds flying contraption powered by eight motorcycle engines
boingboing.net
boingboing.net
I would like to narrate a story which happened with me, I come from low financial background. I have always been to education institutions where people are generally from around my background.
During my pre-university college(10th grade + 2 years, In India) there was a guy who probably couldn't afford engineering. His dad used to work at a automobile mechanical shop. The guy bought a absolute dead discarded engine and built a small airplane with it. The airplane didn't do much. It would just moved around, struggle to take off, loose balance and fall over on the sides. But he was forced to learn so many things on the way. As his classmates we took huge pride in sometimes going to his home and helping him out.
Very soon HAL(Hindustan Aeronautics Limited) took note of it, and sponsored his mechanical engineering. He is doing fine now. Generally when someone does something like this, its not for building an actual airplane, but just out of desperation to do something in life. The product is just a way to express what the person wants.
This was around 2002, I hope I could show you the photo graphs. I don't think they were taken at that time. Affording a camera was a pipe dream then. But I remember there was a small article somewhere in the news paper back then, that's how HAL noticed it.
It's better to build a crappy hovering device with the tools that you've got and the materials that you've got than to sit and comment about how crappy it is.
I've built a fair bit of stuff in my life and not always in a way that was 'responsible engineering' (see 'plane of rotation' comment below, there is an element of experience in there) and it strikes me that if the Wright brothers had not existed that it is guys like this that we would remember as the Wright brothers instead.
Exactly, very correctly put. To be doing something is a lot better than commenting while sitting on the bylines. No matter how bad it is, building something material into existence is thousand times better than just talk.
When effort and work is multiplied over time, the sheer volume of effort and work brings in success sooner or later.
He would have probably done better if he had read a detailed article on the Wright brothers first. Successful flight is a matter of control, and eight engines do not compound well with a lack of background in electrical engineering.
Given that, I bet he wouldn't be too hard-pressed to sort out the control part in typical hacker fashion. How many hackers on HN are expert programmers who weren't formally trained?
You can even keep most of the readme intact :)
http://io9.com/5843571/chinese-farmer-builds-eight+propeller...
Or be completely oblivious to the risks he is incurring.
EDIT: Most comments here are missing the main point, he doesn't care if the center of gravity is high or if the thing is pretty much uncontrollable or that you can't mass produce these or that it has been done before. He just BUILT IT and as far as his goals are concerned he is extremely successful, i.e. the thing gets off the ground. That, to me, is the quintessential hacker spirit.
Still, pretty impressive considering his junior high education and limited resources.
That being said, I'm suprised he didn't go with a Quadracopter type design. Probably not enough lift but even a hexacopter might be easier. And the software to control them is already available on an Arduinio.
I would be very amazed if he knows the Quadracopter design. Same for Arduino.
One can think: If this guy came up with this without Arduinos, robot kits, HN and other social contacts, what could he have done if he had those? I think that's the wrong approach. I know of a few such mechanical tinkerers who wouldn't even have started building what they've built had they known more about the field.
Arhur Fry, the inventor of Post-Its has said that it was good that he was ignorant of the articles on that subject (creating the glue for such a product) because they conclusively showed that it cannot be done.
http://www.hover-bike.com/index.html
http://news.cnet.com/8301-17938_105-20071088-1/will-flying-m...
For it to properly fly, he will need thrust control on each engine (either rotation of variable pitch), gyros, accelerometers and some brains to keep the thing stable. I'd also advise lowering the center of gravity (putting the pilot under the engine plane) to make things easier to the stabilization system.
man, learn the subject before commenting. Over-stability, not un-stability, is a problem of such a design:
http://www.youtube.com/watch?v=C_UtPmb3Z-o
For Hoverbike - http://www.youtube.com/watch?v=P9i7WKdimPU&feature=relat...
It's also unstable because of the high center of gravity. However, it has a specially designed duct that the propellers fit within which creates stabilizing aerodynamic effects, counteracting this instability. Also did you notice the Hiller's lip around the top edge? That's a carefully designed airfoil against which air drawn downward by the propeller passes, creating uniform lift underneath the whole lip edge, all 360 degrees around the outside of the platform! Very clever, but also prevents movement that isn't perfectly balanced upward lift, which is why they were hard to navigate.
The Chinese gentleman's aircraft does not feature either of these and will be unstable. But I'm glad you brought this up, because it's possible that the Hoverbike uses similar effects and is thus more stable, I suppose we'll find out more as Hoverbike prototypes make their way to market and are analyzed. I don't really see an airfoil lip of the same nature on the hoverbike though, but perhaps it's there. The general solution going forward with such things is likely not going to be the Hiller design but is to stabilize using automated flight control as has been mentioned elsewhere in this discussion. The high center of gravity is still a stability problem though that has to be dealt with. With the Chinese craft, there's no way it will be flown any distance untethered using its current design.
the high center of gravity is just one aspect. I'd suggest glancing over this:
http://www.hiller.org/flying-platform.shtml
>Also did you notice the Hiller's lip around the top edge?
the primary purpose of [relatively wide] lips of ducted fans is this:
"Utilizing the Bernoulli principle, 40% of the vehicle's lift was generated by air moving over the ducted fan's leading edge. The remaining 60% of lift was generated by thrust from the counter rotating propellers."
I graduated about two decades ago, but I am quite sure of what I said.
Wanna bet?
If you said this came out of DARPA instead of some guy in China, I doubt you'd get the same critical comments.
http://en.wikipedia.org/wiki/Rotax
My main concern is that an engine failure in that design is an instant crash from whatever height you happen to be at.
http://en.wikipedia.org/wiki/Rotax_912
I've flown an ultralight once and hung around an airfield for a while it's an amazing world. The aircraft that class as 'ultralights' these days can be pretty amazing:
Retractable landing gear on an ultralight? Check ;)
I decided against taking lessons because it felt like I could very easily get addicted to this.
edit: and wikipedia lists another 4 stroke, the 914
I've been flying quite a few times, once after doing its 50 hour overhaul. Really interesting and simple engines.
Pretty cool way of spending time!