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  #31  
Old 03-29-2012, 03:42 PM
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Default Why not the Hover Bike?

I was wondering why most people think that the new Australian "Hover Bike" is not a viable design? Of course, I'm not referring to the actual proto-type that the builder has on display- this machine is known to not be working as yet- it's just a "concept" model.

But I'm curious how the "Hover Bike" is much different than the "Airgeep" that was proven to be a reasonably stable and capable craft. If you take a look at the pictures below, you'll see that the designs are essentially the same, except of course one is much larger and more powerful than the other.

Would the weight distribution be the gremlin on the "Hover Bike", or is it some other feature that would make it less functional than the "Airgeep"?

NOTE: I chose to post the picture of the MODEL "Airgeep" because it's easier to see down into it's ducted-fan design than in actual pictures. There are plenty of real pictures of the "Airgeep" on google images, and youtube.

AIRGEEP (model)

Hover Bike (static display)

Last edited by Chuck Baltzer; 03-30-2012 at 11:27 AM.
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  #32  
Old 03-30-2012, 01:14 PM
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Quote:
Originally Posted by Chuck Baltzer View Post
....the "Airgeep" that was proven to be a reasonably stable and capable craft..
Unfortunately, I am not so sure about that.

The HoverBike is beautiful and mechanically fine, I guess. But multi rotor machines are too complicated and too dangerous to me.
And I think it has to be controlled by a computer, so to speak. That might work - but the fun of controlling it is then gone.
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  #33  
Old 03-30-2012, 01:51 PM
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At walking speeds & low altitude not a problem - more than a couple feet agl or at higher speeds things get ugly fast.
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  #34  
Old 03-31-2012, 02:03 AM
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Yes, there is a huge difference whether we are talking low & slow or beyond that. I only think low & slow here.
The low & slow is where homebuilders can have a lot of fun.
The high & fast machines are different games - too often done for other peoples money.

I hope the HoberBike type - 2 rotor machines - has a future for homebuilders, but even as a low & slow machine "things get ugly fast" if control is not 100 %.
A single rotor thing, as the flying platform, is much more predictable - I think.

Would be nice to here about Malroy's effort to gain control of the HoverBike, but I haven't seen much about this.
Per his homepage it look like he has stepped down from homebuilder to play for other peoples money - or trying to.
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  #35  
Old 04-02-2012, 01:44 PM
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Default Fly by Wire

If flying platforms are ever going to be sold to the public in relatively larger numbers than they have been in previous generations, I believe that the more stability that's built into the craft- the better. For use by the general, more or less, "non-flying" public, a very stable, dampened-down control system is the way to go- think of the Segway scooter: it was built with utter stabilization in mind from the ground up- so that anybody from a kid to a grand parent can hop on and drive without a care.

This should be the philosophy that would be used on things like the "Hover-Bike", no need for lengthy practice, like when learning to fly a helicopter- just hop on and ride, and let the convenience of technology take care of stability.

Interestingly, I've seen several references about stabilizing aircraft with the use of electronic stabilization. Does anybody have a clear understanding of this type of stabilization, that is- what can a home-builder expect to get out of such a unit?

For example- if I built a "Hummingbird" Flying Platform, and wanted the aircraft to stabilize itself without pilot input, is there some kind of a purchasable electronic unit that would accomplish this?

What exactly would the computerized unit do, ie: control the throttle, blade-pitch, swash plate (on a helicopter), variations in prop or rotor speed, some combination of these?

In short- how can a computer keep a rotorcraft in an upright position? And would it work on a craft like the "Hummingbird" platform, which has essentially no type of control mechanisms going to the propellers- except for pilot weight-shift, and throttle?

Additionally, how could a computer stabilize a craft like the "Hover-Bike"?

youtube.com/watch?v=2QTOTZuz3F8


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  #36  
Old 04-02-2012, 02:03 PM
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Chuck- A Segway is a very stable machine. I drove one at Bensen Days0last year. However, if there is a malfunction, you likely won't be hurt except a few skinned up legs. Low and slow in a hover bike, as Brett said, no problem. But at altitude and airspeed, I would be puckering up relying on circuitry keeping the thing from cartwheeling on me, and then hoping a ballistic chute can deploy fast enough, and at the right attitude. Stan
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  #37  
Old 04-02-2012, 03:45 PM
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That's absolutely correct. But, what I'd like to know is- could these stabilizing computers even stabilize these craft at low and slow flight? Or is there a LOT more to how the electronic units work than (figuratively) meets the eye? There would still be an advantage to this type of stabilization in something like the Hover Bike, even at low-and-slow functions.
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  #38  
Old 04-02-2012, 07:26 PM
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Chuck Baltzer ... every one of us likes the looks of the "Hover Bike" and want one .... trouble is .... once we understand how much engine power and fuel tanks it would require ..... we all of a sudden realize none of that fits into the nice display model .

.... and we all wish it wasn't so.
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  #39  
Old 04-03-2012, 01:16 PM
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I agree- the Hover Bike, as it is currently displayed, is most likely not a workable, nor a working, model.

But the question is- in some kind of a similar craft that IS operable, such as the Airgeep or P.A.M. flying platform- are the "electronic stabilization units" that people have mentioned from time to time able to "stabilize" the aircraft, in the same, or similar way that these units stabilize RC model types of aircraft?

And, in addition, exactly how do these "electronic stabilization units" work? Can they work to stabilize ANY rotor-craft, or only certain types- such as helicopters with swash plates?

The Sky Commuter
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  #40  
Old 04-03-2012, 11:02 PM
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I think the HoverBike is workable - except for the controlling.
And he is hovering on 70-90 hp. That's app. twice of a heli, so that's fine.

Yes, stabilize as RC models - you could say.
But of course any electronics/computer/control unit should have something to regulate on which then give variable forces.

The variable forces can come from:
Electric or mechanical driven props.
Vanes in the airstreams of the the main lifting fans/props/rotors.
Move an object to get weight shift.
And a few others.
Or a combination of these.
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  #41  
Old 04-09-2012, 02:29 PM
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Default The Sky Commuter

Does anybody have any knowledge about this "Sky Commuter" project of several years ago? (pictured above and below) I have poured through everything I could find on the "net", but info about this project is particularly scarce.

From what I've read and seen on YouTube (not much), this vehicle prototype actually got off the ground and could hover-taxi at under 10 feet AGL, but any higher and the vehicle would roll, lose control, and end up in a (fortunately) non-lethal crash- the other prototypes of this vehicle were damaged beyond repair in this way.

At least that's what I've read so far. Is this what actually happened? Was this vehicle controllable in ground effect? Were 2 of it's 3 props spinning in one direction, and a third in the opposite? Which prop spun opposite?

Any info on this intriguing failed "aircraft" would be very interesting.

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  #42  
Old 04-09-2012, 06:23 PM
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About 10 years ago they tried to sell one of those on ebay as a collector item ..... asking something like $70k .... don't think it sold.
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  #43  
Old 04-10-2012, 01:01 PM
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Default pricey decoration

It sold for around $131,000.00. The new owner says it's destined for an aviation museum- but I wonder what they're going to try to do with it first- the seller told them: "Don't try this at home!!"

I also read that it was rendered mechanically inoperable before the auction started, but who knows?

It sure would be good to know how these things actually worked, but the very few individuals who were there during flight testing apparently didn't take any video, nor are they interested in making public any specific details of how these unique "vehicles" performed.

Well- they sure looked impressive.

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  #44  
Old 04-10-2012, 01:57 PM
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There's a reason you don't see one flying - just like the Moller stuff.

The only thing either have accomplished is separating investors from their money...
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  #45  
Old 04-10-2012, 02:05 PM
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It looks dangerously unstable to me. The pitch axis is scarey enough, but look at the roll axis and how short coupled it is. I wouldn't want to be within 100 feet of it. Stan
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