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Old Jul 11, 2012, 01:35 AM
Brosol
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Canada
Joined Dec 2010
1,111 Posts
I'm intrigued by your bell head mod. It reminds me of EQMOD's Solo Pro Bell Hiller mod but instead of using 4#3 parts, you are using & adapting V911 head & main blades parts to build a flybar with tilt and pitch angles.

IMO your mod setup is like a bell hiller with a mixer arm at the main blades to mix cyclic inputs from the swash hub and flybar.

I'm curious how it flys vs MSR bell hiller head & flybar setup. Does it fly well in winds?



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Originally Posted by EQMOD View Post
Oh. I love to discuss this part of the topic - hiller, bell, bell hiller;

I will try to keep this as simple as possible.

On a standard 'micro' helicopter, usually there are two agents that control the pitch of the main rotor blade; the flybar and the pilot.

The pilot provides the necessary cyclics on these blades (pitch data over a 360 degree turn) to determine the direction of the heli. The flybar on the other hand provides the necessary cyclics to keep the helicopter upright and stable.

Now it is the way how these two agents are 'arranged' to control the blade cyclics.


Hiller Only
In the hiller-only configuration (typical with the stock walkera 4#3 and 4#3Bs), it is only the flybar that controls the cylics of the main rotor blades and the pilot controls the flybar rotating disc by simply pitching the flybar paddles around a 360 degree rotation. The pilot has no direct control over the pitch of the main rotor blades. The pilot has to tilt the flybar disc first and that disc becomes the 'virtual' swashplate for the main rotor head. Now what is wrong with this configuration ? The control "delay". Because the pilot has no direct influence on the main rotor blade, the pilot has to tilt the flybar disc, and the disc tilts a second after, and that tilt is felt on the main blade and that is when the heli will start responding to the intended direction. Think of this as a steering wheel of car with the wheels responding one second after the driver's command is given. This why people keep on saying that it is difficult to fly a stock 4#3 or 4#3B because of that control response delay.

"Bell Head" - typical with the stock Solo Pro and Walkera Cb100

On this setup, both the pilot and the flybar has direct influence on the main main blade cyclics. This done by using a couple of mixing arms attached to the main blade grip. Those arms provide a mix of cyclic inputs coming from the flybar and the pilot (via servo and swashplate) to the main blade grip.
But in this case, the flybar has no paddles, just tip weights. In short, only the pilot can dictate the direction of the heli while the flybar can only provide a fixed referenced horizontal plane cyclic input to the main blade grip. This design sometimes causes the flybar to provide a 'counter-acting' cylic input against the cyclic input provided by the pilot, meaning the flybar usuall attempts to cancel a portion of the cyclic input provided by the pilot as the flybar disc is always levelled. Sometimes on aggressive flights, the flybar independently acts on its own causing the heli to roll (death roll), pitch up/down on its own.

BELL Hiller Typical of the Stock MSR setup

On this setup same as the bell head design, both the pilot and the flybar has direct influence on the main main blade cyclics. This done by using a couple of mixing arms attached to the main blade grip. Those arms provide a mix of cyclic inputs coming from the flybar and the pilot (via servo and swashplate) to the main blade grip. And what is the difference from the bell head design ? the Pilot also has control on the flybar by means of the pilot pitch applied on the paddles. Basically a combination of the Bell Head and Hiller Only.

In this case, both the pilot's cyclic input and the pilot controlled flybar disc tilt cyclic input compliments and are combined to provide a maximized cyclic data on the main blade grip. This combination is actually the most stable configuration as you dont get those nasty death rolls, flybar to boom strikes, etc. Every bit of cyclic command coming from the pilot is readily felt on the heli at the least delay and the flybar disc is always synchronized with the rotor blade disc.

This is why i modified my hiller-only 4#3 to bell hiller and the bell headed Solo Pro also to bell hiller, and the bell head lama v4 to bell hiller as this how the helis should be controlled - none of the cyclic delays, none of the errant flybar, none of the flybar boom stikes, none of the death rolls, none of the coaxial blade strikes.
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Old Jul 11, 2012, 07:39 AM
I love MOD! & WALKERA & V911!
KKDDMM's Avatar
China, Guangdong, Shenzhen
Joined Jan 2012
336 Posts
The effect of slant of blade is accelerated.

Quote:
Originally Posted by Brosol View Post
I'm intrigued by your bell head mod. It reminds me of EQMOD's Solo Pro Bell Hiller mod but instead of using 4#3 parts, you are using & adapting V911 head & main blades parts to build a flybar with tilt and pitch angles.

IMO your mod setup is like a bell hiller with a mixer arm at the main blades to mix cyclic inputs from the swash hub and flybar.

I'm curious how it flys vs MSR bell hiller head & flybar setup. Does it fly well in winds?
Thank you for getting interested in my mod!

From the outset I thought to reproduce EQMOD's Bell-Hiller mod.
And I thought to make Hiller bar by V911's blade.
On the way making his mod,I hit upon an idea,if I use original linkage,the heli will be able to fly?or will be not?
So I tried this mod,and I succeeded.

But she can not fly stable,there is TBE a little,so it is difficult to control her.
But she can fly very quick and very aggressive so she can fly outdoor.

This head is not Bell,is not Bell-Hiller.
I think the logic of this head is almost same as Bell-head.
But the effect of slant of blade is accelerated.

So I called this mod as Accelerated-Bell.

My original barless is very happy,and this mod is also very happy to fly.
So let's try this mod!
It is not very difficult to reproduce this mod.

see my other blog.
http://plaza.rakuten.co.jp/ringmaker.../201207100000/
http://plaza.rakuten.co.jp/ringmaker.../201205010000/
http://plaza.rakuten.co.jp/ringmaker.../201204290000/
http://plaza.rakuten.co.jp/ringmaker.../201204220000/
http://plaza.rakuten.co.jp/ringmaker.../201204170000/
http://plaza.rakuten.co.jp/ringmaker.../201204140000/
http://plaza.rakuten.co.jp/ringmaker.../201204130000/
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Old Jul 12, 2012, 05:57 AM
I love MOD! & WALKERA & V911!
KKDDMM's Avatar
China, Guangdong, Shenzhen
Joined Jan 2012
336 Posts
and I tried same mod,based 270A,but it is not good......

At first I tried the mod in V911,and succeeded.
Next I tried the same mod in 270A,but her servos is too slow,so I failed......
So I want to try using 270A's head,and using V911's RX.
So I made V911-frankencopter using 270A's head.
If I success it,I will report here.
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