help to clarify this writing.

[noppita]

Please help, I need someone to clarify the meaning of the following terms

"Put I and D terms to zero.
Start tuning your P alone, and then move to I, and then to D."


I = tilt rate I or tilt angle I
D = tilt rate D or tilt angle D
P = tilt rate P or tilt angle P


My octo is not as good as i expected.



thank you so much.

[chschmid]

My best guess would be restore the standard settings.
Please post your motor mixing table. A pict of the multi helps sometimes too.
Please check the alignment of your motors.
The only thing you usually have to tune is the Tilt Rate D and Tilt Angle P to avoid overshoot / Motor satuaration / crash depending on size and power of your multi.

Best
Christof

[noppita]

chschmid

thank you so much for your response, i will gather those infor and post them help.

[noppita]

My octo motor to motor size is 850 mm.

Frame by Noppita8
Motor rctimer
FC AQ version2
ESC by AQ

the attached pid is default.
the possible other than AQ FC could be bad dynamic data, bad frame.

if anyone has system that similar to my octo, please post your pid page.

currently, i lower tilt angle P from 60 to 30.

the copter does not want to hover in one place, it tried to drift in some direction and the copter sometime tilt front or back and sometime left or right by itself without my radio input.

default PID

octo motor table mixer

[chschmid]

Have a look at Larry's octo. He is the octo pro. I think his frame has also somwhat fine arms and therefore some vibes. He added a kind of string/band to get rid of the vibes.



I am sure he will chim in if he can help.

Best

Christof

[noppita]

i am using his motor mix. and my frame is fine with smaller system. never build this big octo with my frame. do you have any recommendation with my pid

[LPR]

Noppita

My PID setting could not be easier, defaults. If your seeing oscillations then you likely have too many vibration getting to your AQ board. The long arms might be amplifying prop and motor vibrations. You could try my trick of damping the vibrations with a string or any way to connect the motors together. You have a motor mix that should work and your able to get in the air with some control so my guess is that vibrations are your problem.
You can see my frame has shorter arms than yours but I still have too much vibrations. Larger diameter carbon arms would likely solve the vibration for my octo but the string of Vectran is much cheaper and I'm able to fly even with a number of chipped props. Any type of string will work but Vectran would likely be the best.

http://www.youtube.com/watch?v=_7im1ExXEug

After you get your octo flying in manual you may have to move your ESC out on the arms near the motors. Your compass might have problems with them mounted near the AQ board. Be sure to have all your power wires twisted so they do not generate a magnetic field.
I always lower Tilt Rate D to 5000 before I try to use RTH and then raise D till I see a little overshoot home when using RTH. Then I lower D a little till RTH has the AQ copter stop right on top of home.

It took me a long time to understand that getting just a few things right while building an AQ copter, motor mix, vibrations, wiring, parameter file and using default PID is all that is needed to have a nice flying copter.

Larry

[noppita]

my frame with longer arm for my first octo could be the problem. i think so. never build something big as this one before. I am thinking of cutting more plates to connect better each arm to another arm to make i more solid. so you pid is really default? what about tilt angle P??????? keep at 60 or change to 45. i have 30 now.

my shown pid is default right? your default and my default is the same right?

[noppita]

I just need to know that i am done all the right thing to pid before moving my electronic stuff around. Good idea to move electronic out. One thing is that all my other system has the similar setup (all electronic near fc board). If my pid is ok, then i will try to fix the vibration problem.

could static and dynamic data be the critical problem?

[noppita]

my current motor mixer is the same as your motor mix right?