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RC VTOL cpable Osprey

Old 03-23-2006, 07:58 AM
  #26  
Barfly
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Default RE: RC VTOL cpable Osprey

vtolman, the 7 footer would have been awesome. I want to do a Vertigo to learn from it. If I can make it as precise in hover as my helis I will have learned something, that's my goal. Then I'd like to try a V22. Did you do a Vertigo? Has anyone done it with electric?

ORIGINAL: vtolman

....valuable time which is better spent on say 5 or more different less complex electric VTOL testbeds which produce more results much quicker.
I fully agree with you.

Cheers from the Barfly.
Old 03-31-2006, 08:40 AM
  #27  
vtolman
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Default RE: RC VTOL cpable Osprey

Ian
I am not sure of your needs, but a suitable mini servo with good torque will do for tilt of those ducted fans you mention.
I would max the travel to 180 deg so they unload the servo at each end of its travel when motors are up or down.
My twin electric uses 2 cheap Hobbico CS-35 - torque 55 oz. - weight 0.95 oz. - speed 0.14 sec. which tilt the motors constantly for pitch and yaw.
I am only guessing, as I have not done the specs, but I dont believe the efficiency of electric ducted fans and lithium’s is good enough for vtol's just yet - unless you are happy with short duration flights 3 - 4 mins.

Barfly
Yes I built and flew the vertigo about 50 flights.
Not sure if anyone has done an electric Vertigo - I decided against it because its vertical thrust to weight ratio is not as good as 2 props.
Basically my twin electric VTOL has only 3 servos and 2 gyros.
A vertigo version requires 1 tilt servo, 2 aileron servos, 1 elev servo and 3 hover vane servos and 3 gyros (that’s 7 servos and 3 gyros)
To compare the twin to a vertigo design you would need a much bigger prop and motor to equal the thrust developed by two smaller motors not to mention its extra weight.
Twin-engine aircraft are more efficient than singles - so I am told.
Also on the Vertigo, the small (hidden) counter torque vanes behind the prop wash use redirected air thrust wasting energy. (Helis waste 20% energy with the tail rotor also)
So I have concluded the best efficiency is 2 counter rotating props.
I did draw plans for an electric (very modified vertigo) vtol with 2 motors together one above the other mounted and tilting in the center of a delta flying wing, at one stage of my process of elimination.
The Vertigo design is complex and has added weight and drag with its ducted prop nacelle.
It is rather complex to build.
If I HAD to do an electric vertigo I would forget the duct and go for a large diam low pitch prop and use the lightest gear you can source.
Kingsley

Old 03-31-2006, 01:53 PM
  #28  
Barfly
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Default RE: RC VTOL cpable Osprey

vtolman,

Once again, I have to agree with you. The reason I was curious about doing a Vertigo in electric is that I could do a lot of tinkering at home, with glow I have to go to the field to test, which wastes a lot of time. However electric gets expensive when we talk about .40 sized models. Your approach, using smaller electric systems, is more practical for development and testing of new models.

The Vertigo caught my eye from the first time I saw it, and it's a proven flyer, so that's the one I'll do first. However, I'm very impressed by the full scale V22 Osprey, and I won't be happy untill I have at least taken a shot at a fully functional model.

On another note, have you thought about the gyroscopic effects of the props on your model? I was playing around with the power system on my GWS Pico Stick recently and was surprised to feel significant precession when tilting it one way or another while at full throttle.

Cheers from the Barfly.
Old 08-03-2006, 09:35 PM
  #29  
alex4orly
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Default RE: RC VTOL cpable Osprey

Hi there VTOL gurus...

I am working on this toy for almost 2 years now, and I am almost ready to fly...
This one is designed as a "Normal" model to fly, and should be able to take-off vertically (I don't think it will actually ever hover...)

http://members.iinet.net.au/~microknox1 and click the "Osprey" button

Cheers
Alex
Old 02-13-2007, 01:33 AM
  #30  
Racer_x1023
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Default RE: RC VTOL cpable Osprey

ORIGINAL: Chris.a

Well I have been thinking about this for quite some time now, and looking at other people's thoughts on this subject, not really concerned about the financial side to things, just design, and I have compiled this design.
Basically, starting with the engines and tilt rotor mechanism, well, (I wasn't sure whether you could program the helicopter settings of a computer transmiter with two modes, if you could it would make this much easier), the simplest way to connect the two would be to have both attatched to a solid rotating shaft, turned by some modified motors or servos, (BIG SERVOS) possibly driven by a worm drive, engines would have to be i/c, I just don't think the power to weight ratio could be cut enough to use electric, but if you think differently please say, yaw in hover I think could be controled by an electric motor with a fan unit built in to the tail, since rudder wouldn't have much effect, and rigged with the rudder channel to alter direction dependant on which way you pushed the stick, throttle control would adjust height in hover, so bassiclly the only controls used in hover would be throtle, rudder, and rotor tilt, however this may leave problems with roll, so dihedral could be built into the wings to counter this. Huge three bladed props with heavily geared down engines. Thats the basis of my design, what do you think? any input would be appreciated.
Thanks Chris.
Hey, i might be able to give you some insite on your project since i work with v-22 ospreys every day of the week. I am stationed in NC at New River Air Station with VMM-263, the first deployable v-22 squadron. If there is anything you need to know about the mechanics of its flight i would be happy to help. It has 2 seperate 6,500 shaft horse power jet engines in each "nacelle" (pod) at the end of both wings that are connected to a tilt-axis gearbox that links to interconnecting drive shaft or ICDS that runs through the wing structure to a mid-wing gear box, that makes sure both rotors run at equal RPM. Also if one engine was to fail, the other would be able to keep the plane flying until it was safe to land. Among many other fail safes it has a triple redundant hydraulic system. One important thing to remember if you do make one able to transition is that when you convert the rotors from helicopter mode to plane mode, you will drop altitude, which is fun when you're inside it! If you need any more help, please feel free to ask. I saw someone else mention it too, but www.tiltrotormech.com has a model built by larry chapman, which is just incredible. I believe he said his material cost was around $2,500 not including the parts he had to fabricate for the tilt-rotor mechanics. Have fun with it though.

-J
Old 03-16-2010, 08:14 PM
  #31  
basskid10107
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Default RE: RC VTOL cpable Osprey



Hey guys I am currently in the proccess of building my own vtol they entire thing is set up Physically. IM running Electric motors and 6 blade props and this baby purs the only problem is i have no way of controlling my yaw axis in hover mode i have counter rotating props and gyros compensating in the roll and pitch but unfortunately though i do not need the gyro nessecarily to avoid rotation but rather have no control watsoever any input on how the osprey controls its yaw in hover mode or any vtol for that matter would be helpful.


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