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foamie crasher
Nov 01, 2007, 10:16 PM
what kind of materials/formulas do i need to make one of these. ;)
ghoti
Nov 02, 2007, 02:20 AM
Where did you find this monster? I have these thoughts:
1) There is a massive ducted fan (well, two of them) fixed by a very slender cantilevered beam so motor vibration will be very bad.
2) There are no control surfaces so vectored thrust must be used for steering but it needs to be rotatable on three axis that we call pitch, roll and yaw. The craft looks to allow only one of these three so I don't see how it can be steered.
This is for starters. Bill
ciurpita
Nov 02, 2007, 07:19 AM
did you see the mythbusters episode where they tried to build this?
BarrelRoll
Nov 02, 2007, 09:04 AM
2) There are no control surfaces so vectored thrust must be used for steering but it needs to be rotatable on three axis that we call pitch, roll and yaw. The craft looks to allow only one of these three so I don't see how it can be steered.
This is for starters. Bill

Yawing seems possible with differential vector thrust, and differential thrust to control roll. But how about pitch? Does it need the pitch control at all?
vintage1
Nov 02, 2007, 09:18 AM
Yawing seems possible with differential vector thrust, and differential thrust to control roll. But how about pitch? Does it need the pitch control at all?

Its just a contra rotating helicopter: treat it as such and it will be simple.
foamie crasher
Nov 02, 2007, 09:36 AM
Yeah I have seen that episode. Suprisingly simple, didn't work though.

Do you need to use gyros and gps ect. or will it just work being bottom heavy.

yes the ducts pitch and yaw by moving together or in opposite directions.

http://www.trekaero.com/ to get to the website that made it.
vintage1
Nov 02, 2007, 10:31 AM
There's some good footage of a pair of rock kittens equipped with these here..
http://www.rathergood.com/gaybar/
JetPlaneFlyer
Nov 02, 2007, 02:18 PM
Its just a contra rotating helicopter: treat it as such and it will be simple.

Possibly not as simple as it sounds because helicopters use cyclic pitch for control... I've yet to see an EDF with cyclic pitch ;)

Steve
vintage1
Nov 04, 2007, 07:20 AM
Possibly not as simple as it sounds because helicopters use cyclic pitch for control... I've yet to see an EDF with cyclic pitch ;)

Steve

So make one.