helicopter lifting problem

[hcwickz]

Hi everyone

my single rotor helicopter are not able to lift up successfully in a balanced manner. It is lifting up in one end and not lifting up in the other end. I believe this is what described as "dismmetry of lift" . And due to the unequal lifting, the heli move only slightly to the left . The direction for the main motor is anti-clockwise whereas the tail motor is clockwise. What can i do to lift my helicopter completely or compensate for the unequal lift ? i am building a helicopter by myself , so i am not using any stimulator to control.
Can anyone enlighten me ? thank you

[remotemadness]

Hi bro..

What brand of single helicopter u flying..?

Did u check all your mechanical and electric set up is correct.. ?

Most RC Heli we fly main blade spin CW looking from top.. And tail spin CCW, looking from the right side..

So maybe if u give more information.. It'll help anyone that hope to help u..

Worse case.. Go to a flying site.. Let someone check for u..

Q

[xuen7]

Hi everyone

my single rotor helicopter are not able to lift up successfully in a balanced manner. It is lifting up in one end and not lifting up in the other end. I believe this is what described as "dismmetry of lift" . And due to the unequal lifting, the heli move only slightly to the left . The direction for the main motor is anti-clockwise whereas the tail motor is clockwise. What can i do to lift my helicopter completely or compensate for the unequal lift ? i am building a helicopter by myself , so i am not using any stimulator to control.
Can anyone enlighten me ? thank you

Have you ever tried flying a collective pitch heli yet? or know how to? cause if not you might wanna learn that first... or at least if you need your heli tested, at least let someone with experience do it for you..

and the term you used "dis-symmetry of lift" not sure where you got this phrase from but i think it means your heli is unbalanced?

[Super-Hornet]

"dis-symmetry of lift" is a term use in real, full size heli. The situation happen during heli travel in forward movement whereby the blade moving towards the incoming air (or toward the forward where the heli is moving forward) experiencing more lifting than the retreating blade (blade moving away from the incoming air).

When this happen, the heli will suffers from a roll over effect.

In our R.C. heli, this problem is not that obvious...unless u are flying pretty fast.

Practically all R.C. heli spin at CW rotation..with some minor, U.S. made R.C. heli spin CCW. For me, all my heli spin CCW in order to mimic the real heli that my scale is trying to mimic from.

In a normal CW heli, if u look carefully, it is actually tilt to the right. For the CCW rotation heli, it tilt to the left. This is normal. U just have to get used to it.

But make sure your heli swash plate are all properly align 1st. It your heli keep on drifting to the left, it could be your swash plate alignment is out (tilted to the left)

SH

[xuen7]

This tilting to the right of the body of the heli during hovering, is there anyway to reduce it or get rid of it? is there a primary cause to this tilting?

It doesnt affect the flying or anything cause the blades are still spinning very parallel to the ground and the gyro on the heli has managed to compensate for it.. but it doesnt really look very good flying with a slight tilt...

it cant be that normal right? cause i see videos or many helis without the tilt...

[hcwickz]

Hi bro..

What brand of single helicopter u flying..?

Did u check all your mechanical and electric set up is correct.. ?

Most RC Heli we fly main blade spin CW looking from top.. And tail spin CCW, looking from the right side..

So maybe if u give more information.. It'll help anyone that hope to help u..

Worse case.. Go to a flying site.. Let someone check for u..

Q

i am not using any brand , its a helicopter i build all by my own for project.
So i wonder if it work the same as mine , main blade - anti , tail blade , clockwise . i am using two yaw rate gyro sensor for the 2 motors , is that useful ?

[hcwickz]

This tilting to the right of the body of the heli during hovering, is there anyway to reduce it or get rid of it? is there a primary cause to this tilting?

It doesnt affect the flying or anything cause the blades are still spinning very parallel to the ground and the gyro on the heli has managed to compensate for it.. but it doesnt really look very good flying with a slight tilt...

it cant be that normal right? cause i see videos or many helis without the tilt...

ya i have a yaw rate gyro sensor , isnt useful to compensate ? btw , my helicopter need not to fly , just a lift will do , i will show you my helis (look different from other model helicopter)

[hcwickz]

"dis-symmetry of lift" is a term use in real, full size heli. The situation happen during heli travel in forward movement whereby the blade moving towards the incoming air (or toward the forward where the heli is moving forward) experiencing more lifting than the retreating blade (blade moving away from the incoming air).

When this happen, the heli will suffers from a roll over effect.

In our R.C. heli, this problem is not that obvious...unless u are flying pretty fast.

Practically all R.C. heli spin at CW rotation..with some minor, U.S. made R.C. heli spin CCW. For me, all my heli spin CCW in order to mimic the real heli that my scale is trying to mimic from.

In a normal CW heli, if u look carefully, it is actually tilt to the right. For the CCW rotation heli, it tilt to the left. This is normal. U just have to get used to it.

But make sure your heli swash plate are all properly align 1st. It your heli keep on drifting to the left, it could be your swash plate alignment is out (tilted to the left)

SH

I dun have a swash plate with me . i am using a wooden stick as the helis platform. If swash plate can help in my problem , i will go for it. but can it be put onto the platform , i am not sure about that

[xuen7]

thats some exciting stuff you got going on over there bro.., keep it up and keep us posted please.. i wanna know more..

[Super-Hornet]

Let me see if I got it right... your main rotor is actually a propeller...then the heli body is the stick. At the end of the stick, u have the tail rotor (controlled by another motor).

How do u control cyclic movement? Tilting the main motor/rotor?

And then, your main rotor is at one end and tail and one end, this will create an imbalance lifting. U see, when u spin up the main motor, it create lift. That lift will try to take off and lifting the stick end where the motor is connected to... but your tail do not have anything to lift. Thus, what u get is, your heli will try to lift and turn toward the tail.

U should put your main rotor at the center instead. If u want to put your main rotor at the one end, then u need another at the other end to balance up the lifting.


SH

[hcwickz]

Let me see if I got it right... your main rotor is actually a propeller...then the heli body is the stick. At the end of the stick, u have the tail rotor (controlled by another motor).

How do u control cyclic movement? Tilting the main motor/rotor?

And then, your main rotor is at one end and tail and one end, this will create an imbalance lifting. U see, when u spin up the main motor, it create lift. That lift will try to take off and lifting the stick end where the motor is connected to... but your tail do not have anything to lift. Thus, what u get is, your heli will try to lift and turn toward the tail.

U should put your main rotor at the center instead. If u want to put your main rotor at the one end, then u need another at the other end to balance up the lifting.


SH

ya you are right. so the lift is more on the left than the right . What i see is the left side of the body lift up while the right side stay partially down. So you mean i have to add 1 more main motor at another end to balance ? can i add weights instead to balance ? not good if its good though

[Super-Hornet]

If u use 2 lifting motor, one on each side of the stick, it should balance up the "flying craft".

Alternatively, put the main lifting motor at the center of gravity of the stick....tail motor on one end and battery + electronics on the other end, then it also balance up. It is like fixed pitch heli... but u have to find a way to control the tilting of the "craft"...and thus, cyclic control.

SH

[hcwickz]

i think i should go ahead with my own design as teacher ask me to follow that.
is there any quick alternative to solve tilting , example - using swashplate or gyro ?

[ongbenghui]

i think i should go ahead with my own design as teacher ask me to follow that.
is there any quick alternative to solve tilting , example - using swashplate or gyro ?

Seriously, I really like to know Which School and the name of the Teacher.

[xuen7]

I am guessing ITE?