Chinese homemade multicopter beaten... 10 times...

[piisfish 140]

by german engineers...
http://www.gizmodo.fr/2011/11/02/les-ailes-d%E2%80%99icare-se-modernisent-avec-le-volo-multicopter.html
this one is electric, controls are as simple as can be... If you can fly a remote-control multicopter, you can fly this one....

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[JohnMitchell 16]

Le link, c'est-ne marche pas.

[piisfish 140]

copy-paste doesn't always work well with links...
try this
http://www.vincentabry.com/e-volo-le-premier-multicoptere-electrique-avec-un-homme-aux-commandes-13944

e-volo

http://e-volo.com/Home.html

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[quade 4]

Nice. That one shows a bit of promise. Very impressive they used electric. The world's first electric manned helicopter of any kind only took flight in mid-August, 2011.

http://www.geeky-gadgets.com/the-worlds-first-electric-helicopter-05-09-2011/

quade -
The World's Most Boring Skydiver

[JohnMitchell 16]

I want one.

[spikes2020 0]

sweet, its like the Wright brothers all over again

Cheers

Jon W

[piisfish 140]

Quote

I want one.

id does look safer than the chinese model with 8 moped engines with wooden props

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[beowulf 1]

Using the big rubber ball as a landing gear is a pretty cool idea!

[pattersd 0]

Helicopter jumps?

[JohnMitchell 16]

Quote

Helicopter jumps?

I'd want to be a hanger.

[JohnMitchell 16]

I wonder if one or two large rotors are more efficient than many small rotors for developing lift? My intuition says it should be.

[quade 4]

Quote

I wonder if one or two large rotors are more efficient than many small rotors for developing lift? My intuition says it should be.

Prop efficiency is a black art to me. I do know that a traditional helicopter is going to be a variable pitched beast and so far all the omni-copters I've ever seen are fixed pitch. Fixed pitch props are most efficient at a specific RPM and for any given conditions there will be a specific amount of torque required to get them there, so that alone may be the biggest factor when it comes to the answer we're talking about.

That said, the props being used in this omni-copter look as if they were possibly bought off the shelf with their length and pitch picked to match the motor torque. My guess is the counter-rotating helicopter blades were custom built; seriously tricky stuff to do efficiently.

quade -
The World's Most Boring Skydiver

[Squeak 17]

Quote

Quote

Helicopter jumps?

I'd want to be a hanger.

you want to be a large shed where they store aircraft and tools?

You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
How's yours doing?

[billvon 3,070]

>I wonder if one or two large rotors are more efficient than many small rotors for developing lift?

They most definitely are. However you get two huge advantages with multiple rotors - redundancy and elimination of mechanical linkages.

With one rotor you need rotor linkages for pitch and roll and a powered tail for yaw compensation and control. That's a very complex system, and if anything fails, you're going down.

With two rotors you can remove one of those linkages, but you still haven't bought yourself much - you still need that tail rotor. and the rotors cannot be fixed.

With four rotors you can eliminate the tail rotor and go to all fixed pitch props. This is a big step forward in reliability; no moving parts on the rotors.

With eight rotors you can eliminate the tail rotor, go to all fixed pitch props AND survive the loss of one engine/prop. And with the smaller rotors, the vehicle can survive the loss of of a rotor blade, either through sacrificial mounts or fail-intact designs for the motor mounts.

Ducted fans are considerably more efficient than open rotors; that's probably the next step for this effort.

[billvon 3,070]

>this one is electric, controls are as simple as can be...

I'd say the controls are WAY more complex; pretty sure I saw piezo gyros in that control system in that video. But as Airbus, Boeing et al have demonstrated you can design pretty reliable fly-by-wire systems these days that hide much of that complexity from the pilot.

[JohnMitchell 16]

Thanks for the pros/cons list, Bill. Very nice analysis of the trade-offs.