I made a big hexacopter with cuav v5+ flight control and big x9plus hobbywing motors, it takes off well, but when I move it in one direction, at a very low speed, when braking, it hits back and forth twice, but if the speed increases a little, when When braking, it can’t hold itself and it rocks back and forth and completely loses its balance. Where is the problem? I installed the same flight control on the 450 frame and it responds and works easily, but on this size, the problem is when braking. We are getting caught, the balance of the bird is disturbed in a sinusoidal way and it goes back and forth, it cannot brake and stay in place
The problem is that your craft isn’t configured and tuned correctly.
Read and follow the How to methodically tune (almost) any multicopter guide. Download the methodic configurator, follow each step in the configurator and edit the parameters and “param changed reason” to suit your copter. Upload them to the FC one by one as you read along. The guide and configurator tell you what documentation to read, what parameters to change and overall what to do at any given time. Do not skip any steps! Anything that might seem like a shortcut will result in more work and/or a worse tuned copter in the end.
hello
Thank you for your help and guidance
Only two things, one, I had not installed the flight control in the center because our frame was not able to be installed, so I installed it in another place, in front of the plane, and secondly, the power used by the motors was about 160 amps, and the output power of the PMU flight was maximized for 14 cells of 90 amperes and fearing that it will burn, I did not take the power of the motors from pmun and gave it directly to the motors
If there is a mistake in my writing, it is due to the use of Google’s online translator
I am interested in seeing a .bin log file from that large copter for a number of reasons. There’s quite a lot of settings I can help with, but the Configurator GUI is the way forward now.
Are you flying with loiter mode?
If yes, may I know what is your LOIT_BRK_DELAY value?
If your drone is tuned, low noise and vibration, maybe this post may help you.
The moment of braking is two hundredths of a second. I noticed that without setting the gain, I flew the bird in loiter mode, which was wrong, and I should have flown in althold mode first, and then autotuned, and after completing the gains, I went to loiter, and because the gains were not set When he wanted to brake, he tried to stop, but he couldn’t, and this led to a gradual and sinusoidal increase in the amount of confusion, which eventually led to the fall of the bird. Is this my prediction correct?
You skiped configuration steps and that caused the vehicle to crash.
Post pictures and .bin log file otherwise no one can help you.
The moment of braking is two hundredths of a second. I noticed that without setting the gain, I flew the bird in loiter mode, which was wrong, and I should have flown in althold mode first, and then autotuned, and after completing the gains, I went to loiter, and because the gains were not set When he wanted to brake, he tried to stop, but he couldn’t, and this led to a gradual and sinusoidal increase in the amount of confusion, which eventually led to the fall of the bird. Is this my prediction correct?
در تاریخ یکشنبه ۱۱ اوت ۲۰۲۴، ۰۴:۰۲ Amilcar Lucas via ArduPilot Discourse <noreply@ardupilot.org> نوشت:
No your prediction is not correct.
See my answer above
We cant help further unless you provide the .bin log so we can see what went wrong and make suggestions, or you follow the Methodic Configurator completely.
Loiter mode is highly tested and reliable, it’s only affected by poor position information or poor tuning.
In about 99% of cases Loiter issues are caused by poor tuning and the copter has no chance of doing what you ask of it.
1 Like