Ken just needs bigger motors......
Franklin
Posts: 4,747
http://www.adafruit.com/blog/2011/11/01/worlds-first-manned-flight-with-an-electric-multicopter/
Not sure I'd want to sit in the path of all those blades though.
Not sure I'd want to sit in the path of all those blades though.
Comments
-Phil
The truth is, we have the technology right now, today for a flying car.... the reality is that nobody wants to pay for the cost of fuel to keep it in the air for more than 15 minutes at a time.
Turnigy has a couple of really large motors - here's one:
http://hobbyking.com/hobbyking/store/__5142__Turnigy_80_100_B_130Kv_Brushless_Outrunner_eq_70_55_.html
The problem at these larger sizes is to find counter-rotating propellers.
Also not sure about the total batteries required to get any amount of flight, but you'd be weighted down so much you couldn't move if the pilot wanted a ten minute flight. The e-volo guys you found above talk about a hybrid model where they use a gas engine for power. I don't think they'll be able to charge faster than they draw power, but it'll be fun to watch.
Did you see the Chinese octocopter with gasoline engines? I think the pilot was using some sort of pull strings on the throttle. Very dangerous.
Very interesting. Thanks for sharing!
Ken Gracey
P.S. I'm still trying to figure out if that big Turnigy motor above actually exists. . . .anybody know?
I've seen too many Landing Gear Failures
-Matt
With one of those contraptions you at least wouldn't need a camera and video link for POV piloting!
-Phil
You'd make a really good guinea pig since you're up for anything. Brings the idea of "taking one for the company" to a whole new level. We better straighten out our workmen's comp policy before we load you into such a contraption.
I see you've been inside of the cyclone lately, or that you put Scott inside the cyclone. Maybe we could convert that tool to fly. Did you get it fixed, BTW? Did the hammer do the job?
I'm ready to build a much larger quadcopter, thanks to Franklin. Please shield me from such posts in the future. This addiction is getting expensive to feed but it's better than golf or racing cars I guess.
Ken Gracey
Do you have to have counter rotating propellers? Just thinking if you have a long arm and you have two props on the end, side by side and counter rotating, the torque forces would be close to cancelling? Or not much different to the props being one above the other.
And/or, you could always mount two props with separate motors one above the other. Costs a little extra weight in terms of mounting hardware but not much.
It simplifies things does it not, if you don't have to have counter rotating props with hollow shafts etc (like on model helicopters).
Which means, therefore, that we have removed the last remaining barrier to building this, and thus work must begin at once on this giant project! *grin*
Soon you will be able to fly over to Franklin's house and tell him that personally!
They use a Pilates ball as landing gear, at least it's always deployed.
-Phil
This appears to be a great accomplishment and will fit in with the future.
As Beau implies, a light weight fuel cell is needed for longer flights.
I see no craft protection for the pilot.
But then it was the same at Kitty Hawk.
The first flight always takes on risk.
It just needs to be able to supply enough power that the batteries doesn't fully drain before the flight ends(if they do, the flight ends... )
The engine delivers a set amount of power continuousy, and the peaks comes from batteries.
Also, as this gasoline engine will be running at peak performance all the time, it can be optimised for that speed.
It's just a question of deciding how long a flight-time is desired and the size/weight of the batteries, and you'll find how larg a gas engine you need.
(It's the same principle as 'plug-in hybrids')
Certainly an internal combustion engine can support its own weight - just look at nitro powered helicopters. But for quadcopters, the mechanical linkages become impractical, and this is the modern world where you want computer (Parallax Propeller) controlled stability (the Propeller will hold bsnut's life in its hands!).
http://www.rchelicopterfun.com/model-gas-engines.html 22cc for 2HP (?? 1500W but there will be losses along the way).
I wonder if it is possible to find out the current consumption of Franklin's multicopter when it was flying?
Ken,
I believe you find two of them on this craft.
One for lift and one for thrust.
2:1 reduction on thrust motor. I'm not sure on the lift.
More info here:
http://www.hovercraft.com/content/index.php?main_page=index&cPath=30_247
Cheers,
Jim
Ummm... I have a bad feeling about that! I just see mincing, chopping and slicing. Brrrrr....
Amanda
You are a master of understatement. Got to give him credit though - very much in the spirit of some of the earliest attempts at powered flight!
As far as I can tell, the guy is using 16 motors... assuming the guy plus his equip weighs approx 300-400 pounds , that's roughly 20-25 pounds of force per motor.
That's not to mention ground effects that initially have a reverse effect when taking off... <-- Basically if air is being forced in one direction(down) and has nowhere to go but to radiate outward in all directions, this 'ground effect' acts like a wing and causes lift, only in this case the wing IS the ground.
Here is a citation of the above phenomenon ... try it , it works...
http://www.seykota.com/rm/spool_card/spool_card.htm
Personally, I would prefer NOT to be sitting on the same plane as all those propellers. I'd much rather hang below all the rotating gear in a manner similar to a traditional helicopter. This also offers a more stable platform as the center of gravity is much lower than the center of lift. But it does indicate that the landing gear would require a redesign.
Being the first has its hazards, as even the Wright brothers managed to kill their first Army test pilot.
I absolutely love the fact that the Parallax Propeller is so well suited for this form of flight - nothing else provides such simple elegant control of four motors or even larger multiples.
I suppose that might mean redundant ESCs and a redundant motor control system. It also means automatic landing on low power. These devices do NOT have auto-gyration as a fall back option. One might even include an ultralight parachute deployment system (uses an explosive charge) to be deployed if there is a complete electrical shutdown.
Testing should include how to manage a safe landing with at least one of the motors in failure mode (is that really possible?).
http://www.usairborne.com/brs_parachute.htm
You don't have a glide path - remember that.