Hello there i am using Pixhawk cube orange+ with mini carrier board. 27000 mAH solid state battery with t motor custom motor similar to mn6007s with 22.4*8 inch mf2211 t motor propeller with flame 70a esc. All up weight of drone is near 7.5 kgs and having wheel base of 990 mm.
I have configured notch frequency correctly by analyzing graphs. But after that i am stuck at tuning part.
I have started autotuning at base PIDs but i am not confident about performance of drone. It seems to jerky for me.
Than i have manually set PIDs by log analysis to really really lower values just to make sure next autotune as good as possible. It successfully worked but my PIDs are too low also below default values and output was really too bad.
Than from stock values i have started manually tuning my drone and it really helped a lot like i am attaching log file here. Log
Than i decided to do autotune tune again but same goes again. Autotune has lowered my PIDs value too much and it’s not good at all. Video Log of autotune flight
Now i doubt about my motor thrust expo value because i think it has very crucial role in autotune result . My current value is 0.2 for flame 70a t motor esc as suggested by initial parameter calculator, but i doubt that it is reason for failure of autotune. As per 22.4 inch propeller i think value should be nearly around 0.7. Am i right or missing something here ?
Also i have tried quick tune this morning and i have nearly crashed my drone. It happened second time firstly with my 30 inch build and now 22.4inch. I think quick tune works well only for small quad copters am i right ? Video of quick tune
@Aayush you are not following the recommended order of steps. And setting the PIDs to low values is a bad idea.
If you want to learn to do it correctly use ArduPilot methodic configurator software to get the job done. Do not be creative, follow all the steps in the sequence in the order that they are presented. It has an AI assistant that can answer questions.
I really appreciate using idea of using methodic configuratoe but i am not sure about parameters like smax to change which configurator suggest to change so i am afraid of using it and instead follow steps mentioned in wiki
I have lowered PIDs befor autotune to low because on stock values drone is oscillating too much so i tried to lower PIDs which eventually gives better performence in autotune process but not in result
Does t motorr flame 70a esc needs slew rate ?
Because as far s i know only digital protocols needs to be sync via parameters otherwise we are doing esc calibraton for syncing am i correct ?
No, it nothing to do with digital or analog It has to do with the rotating magnetic field of the motor stator being in sync with the magnetic field of the permanent magnets in the motor rotor.
Google “bushless motor de-sync” for more information.
hey i have learned and configured as per methodic configurator but still facing issues with autotune i am not able to do autotune successfully. Sometimes PIDs are not acceptable and sometimes i have to stop autotune in order to save drone.
as you can see here in this graph.
You can probably disable the harmonic notch filter to ensure it’s not interfering at least until there is more flight time and data. INS_HNTCH_ENABLE,0
The settings stay in place for later when you enable it again.
Now set up the VTOL Quicktune script and run that.
Let’s see a .bin log from a flight in AltHold and Loiter after all that.
Anyway, make all those other changes, being sure to get all the motors exactly level, because I believe it is actually an issue - just check your motor outputs.
It looks like yaw imbalance to me, and that’s caused by twisted motor mounts, unless you made a rookie error and put very different pitch props on CW and CCW motors (unlikely )
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