kazmod1

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CC3D non intented mix throtle ailrons
« on: August 08, 2018, 04:01:22 pm »
Hi,

first hello for everybody. I'm new at this forum. I'm very interested in using this cheap controller CC3D. It is instaled on my fixed wing model Walrus from Hobbyking.


All is working correctly to the moment when I'm trying to rotate motor with throtle.  In Attitude mode the giving only throttle has as a additional effect- ailrons start to
moving. This take a little time for ailorns to achieved final deflection.


For a moment I have made in program Librepilot the correction like :
   I have changed the filtering value for accelometers from 0.05  to 0.2 (max. value) with no effect.
   I have removed the prop - no effect
   I have reversed the motor rotation - no effect

You, on this forum you have very large experience with FC. What do you think about CC3D. How often they have this kind of problems. Where I can buy good CC3D? What kind of places should I avoid because they are known as selling bad controllers?
   
I do not have any other ideas what I need to do. Perhaps someone has this problem, or can explain it. Thanks in advance.
« Last Edit: August 08, 2018, 05:34:23 pm by kazmod1 »
Kaz

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Re: CC3D non intented mix throtle ailrons
« Reply #1 on: August 08, 2018, 06:32:43 pm »
Seems normal the board try to compensate a Attitude (Roll) error while the vehicle do not bank and is not level.
Try removing the motor controller wire (or disconnect the motor) and look if the effect is the same.

Vibrations can affect the Attitude estimation, look at PFD (Flight data tab) if the Roll is affected by vibrations and goes crazy.

kazmod1

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Re: CC3D non intented mix throtle ailrons
« Reply #2 on: August 10, 2018, 12:30:50 pm »
Thanks for answer.  Yes, I have verified your suggestion but result is negative.

Problem is : at moment you start the motor ailrons start to move slowly and after the time 5-10 sek the deflection is constant with value about 8 mm.
When motor stops ailrons go to neutral positon at once.
It is like slow integration of vibrations.
Kaz

kazmod1

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Re: CC3D non intented mix throtle ailrons
« Reply #3 on: August 10, 2018, 03:42:25 pm »
I have remarque, that in my second model ( Hummer, foam) , this time elevator make problem. When motor start the elevator goes up and during about 10 sek his deflection is about 6-7 mm up.  What you think? what can be done? 
Kaz

f5soh

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Re: CC3D non intented mix throtle ailrons
« Reply #4 on: August 10, 2018, 07:23:47 pm »
Similar answer as previous post :
If board is not perfectly level, after you apply Throttle the stabilization is active and try to compensate the Attitude error.
While the elevator is 7mm up, what happens if you move the fuselage on pitch axis ?

Re: CC3D non intented mix throtle ailrons
« Reply #5 on: August 10, 2018, 08:16:03 pm »
Yes, that is possibly just the I term winding up.  Pretend it is in the air.  When you see the ailerons moving, pick it up and roll the fuselage slightly like would happen in the air with those aileron positions.  You will find that if you hold a little roll position that the ailerons go back to neutral and stay there.  Say that is 5 degrees of left roll.  Well you have found that your board is not mounted level, or your levelling calibration was not done well.  You can fix this with Attitude->Settings->RotateVirtual.

  if it is drifting forward (down elevator for fixed wing) you subtract from pitch
  if it is drifting left (left roll for fixed wing) you subtract from roll

kazmod1

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Re: CC3D non intented mix throtle ailrons
« Reply #6 on: August 10, 2018, 08:41:17 pm »
Thanks for the answers. I hope that you are perfectly right and I will see this effect soon. Thanks !
Kaz

kazmod1

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Re: CC3D non intented mix throtle ailrons
« Reply #7 on: August 11, 2018, 07:05:20 pm »
Frankly, I'm new in this field. Can you explain what means  "up wind or upwind"  or  "unwind" ? 
Kaz

Re: CC3D non intented mix throtle ailrons
« Reply #8 on: August 12, 2018, 04:16:32 am »
"I" term (Integrating, over time) in PID keeps trying harder and harder if it is not level.  So if not level then over time it will move the control more and more without end until it is finally level.  This does not happen unless it is actually flying, so it moves the control to as far as it will go.

Research what PID is and how it works.  :)